scholarly journals Proteogenomic Subtyping of Chronic Lymphocytic Leukemia Identifies a Novel Poor Outcome Subgroup with a Distinct Drug Response Profile

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 10-11
Author(s):  
Sophie A. Herbst ◽  
Mattias Vesterlund ◽  
Rozbeh Jafari ◽  
Ioannis Siavelis ◽  
Matthias Stahl ◽  
...  

Background: Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the western world and shows a very heterogeneous clinical course. While the genetic landscape of CLL has been well characterized during recent years it can only partially explain the underlying biology of this heterogeneity. Proteogenomics could offer a valuable tool to fill this gap and improve the understanding of CLL biology. Methods: Here, we performed a large proteogenomic analysis (n=263) of three clinically annotated CLL cohorts: For the discovery cohort (Germany_1: n=68) we performed in-depth HiRIEF LC-MS based proteomics (more than 9000 proteins quantified) alongside genome-, transcriptome and ex-vivo drug response-profiling with 43 clinically established drugs. The proteome of two additional validation cohorts (Germany_2: n=44, Sweden_1: n=89), were characterized by data-independent acquisition (DIA) mass spectrometry. Results: To connect the CLL genotype with the molecular phenotype, we investigated associations between recurrent genetic alterations of CLL, mRNA expression and protein abundance. We found that trisomy 12, IGHV status and SF3B1 mutations had the greatest impact on protein abundances. CLL specific recurrent chromosomal deletions and gains (trisomy 12, del17p, del13q, del11q, gain8q24) consistently impacted on gene expression and protein abundance through gene dosage effects. We explored functional consequences of these gene dosage effects and found that the additional copy of chromosome 12 increased the abundance of central B-cell receptor (BCR) protein complexes through cis- and trans-effects, which could explain the increased response of trisomy 12 patient samples to BCR inhibition. Somatic mutations of TP53, ATM and XPO1 were associated with less, but specific and biologically-relevant protein abundance changes. p53 for instance, was the most upregulated protein in TP53 mutated samples, owing to the known stabilisation of mutant p53. This effect was not detectable on transcript level. ATM and XPO1 protein abundances were significantly lower in ATM and XPO1 mutated cases, indicating loss-of-function phenotypes of these mutations. To understand global similarities and differences between CLL patients on the proteomic level, we performed unsupervised clustering and identified clinically meaningful subgroups. Unsupervised clustering of the proteomics data identified six subgroups with contrasting clinical behaviour. TP53 mutations, IGHV status, trisomy 12 and their interactions explained five subgroups. These results show that quantitative mass spectrometry-based proteomics distinguished clinically relevant subgroups of CLL. Most importantly, we identified a previously unappreciated subgroup of CLL, comprising 20% of all cases, which could be uncovered by proteomic profiling and showed no association with frequent genetic or transcriptional alterations. This new CLL subgroup was characterized by accelerated disease progression, SF3B1 mutation-independent splicing alterations, metabolomic reprogramming and increased vulnerability to inhibitors of metabolic enzymes and the proteasome. Surprisingly, major BCR signaling proteins were downregulated in this subgroup, suggesting less dependence on BCR activity. In accordance with this observation, an unsupervised analysis revealed that low levels of many BCR signaling proteins (e.g. PLCG2 and PIK3CD) were associated with short time to next treatment. The existence of this subgroup could be confirmed in the validation cohorts. Finally, we performed an unsupervised multi-omics factor analysis (MOFA) across all omics data sets in parallel. This unsupervised analysis confirmed the existence of the above identified CLL subgroups and an important role of SF3B1 mutation-independent splicing alterations in CLL. Conclusion: Our integrative multi-omics analysis provides the first comprehensive overview of the interplay between genetic variants, the transcriptome, and the proteome, along with functional consequences for drug response and clinical outcome in CLL. Importantly, we identified a new subgroup with accelerated disease progression, a distinct proteomic signature and a clinically exploitable drug sensitivity profile. Figure Disclosures Mueller-Tidow: BiolineRx: Research Funding; Daiichi Sankyo: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; BMBF: Research Funding; Wilhelm-Sander-Stiftung: Research Funding; Jose-Carreras-Siftung: Research Funding; Bayer AG: Research Funding; Deutsche Krebshilfe: Research Funding; Deutsche Forschungsgemeinschaft: Research Funding; Janssen-Cilag Gmbh: Membership on an entity's Board of Directors or advisory committees. Dreger:Neovii: Research Funding; Roche: Consultancy, Speakers Bureau; Riemser: Consultancy, Research Funding, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Janssen: Consultancy; Gilead: Consultancy, Speakers Bureau; AstraZeneca: Consultancy; AbbVie: Consultancy, Speakers Bureau. Stilgenbauer:Pharmacyclics: Consultancy, Honoraria, Other, Research Funding; Novartis: Consultancy, Honoraria, Other, Research Funding; Mundipharma: Consultancy, Honoraria, Other, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Other: travel support, Research Funding; GlaxoSmithKline: Consultancy, Honoraria, Other: travel support, Research Funding; Gilead: Consultancy, Honoraria, Other: travel support, Research Funding; Genzyme: Consultancy, Honoraria, Other: travel support, Research Funding; Genentech: Consultancy, Honoraria, Other: travel support, Research Funding; F. Hoffmann-LaRoche: Consultancy, Honoraria, Other: travel support, Research Funding; Celgene: Consultancy, Honoraria, Other: travel support, Research Funding; Boehringer-Ingelheim: Consultancy, Honoraria, Other: travel support, Research Funding; Amgen: Consultancy, Honoraria, Other: travel support, Research Funding; AbbVie: Consultancy, Honoraria, Other: travel support, Research Funding. Tausch:Roche: Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Research Funding. Dietrich:Roche: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; KITE: Membership on an entity's Board of Directors or advisory committees.

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 4678-4678
Author(s):  
Sevastianos Chatzidavid ◽  
Christina-Nefeli Kontandreopoulou ◽  
Panagiotis T Diamantopoulos ◽  
Nefeli Giannakopoulou ◽  
Panagiota Katsiampoura ◽  
...  

Abstract Background Ribonucleotide Reductase (RNR) is responsible for converting ribonucleotides to deoxyribonucleotides required for DNA replication and repair. RNR consists of two subunits, termed subunit 1 (RRM1) and 2 (RRM2). Imbalance in the regulation of RNR activity and control of dNTPs' pool leads to genomic instability and increases mutation rate. RNR expression has been associated with prognosis in pancreatic, non-small-cell lung, breast, and biliary tract cancer. However, RNR expression in chronic lymphocytic leukemia (CLL) and its possible prognostic role have not been investigated yet. Aim In this study we evaluate the possible prognostic role of RNR expression in CLL. Method The study comprised patients with immunophenotypically confirmed disease at the time of sample collection. Peripheral whole blood samples were collected from 84, 27, 15, and 9 patients before treatment, after one, two, and three lines of treatment respectively. RNA extraction and reverse transcription were carried out using standard protocols. A Taqman based real-time PCR was performed on a CFX96 RT-PCR system (Bio-Rad Laboratories, Hercules, CA, USA). For both the housekeeping and target genes, a Taqman primer/probe mix was used according to the manufacturer's instructions (Applied Biosystems, Foster City, CA, USA). RRM1 and RRM2 mRNA levels were expressed as an RRM1-2/GAPDH ratio. Western blot analysis was performed to quantify the RRM1 protein levels in a random sample of 41 patients. Antibodies used were: RRM1 #3388, β-actin #4967 and anti-rabbit IgG HRP-conjugated #7074 (Cell Signaling Technology, Danvers, MA, USA). Detection was done using the ECL western blotting reagents. Statistical analysis was conducted to study the possible correlations between the variables. All reported p values are two-tailed. Statistical significance was set at p<0.05 and analyses were conducted using SPSS statistical software (version 22.0). Results From 135 CLL patients included in the study 56.3% were female and the median age at diagnosis was 64 years. Peripheral blood was collected in 84 treatment-naïve patients (62.2%). Median follow up was 6.66 years (3.47 ─ 11.13) and median time from diagnosis until 1st line treatment was 23.1 months (IQR: 5.8 - 56.5 months). Out of 135 patients, 69 (51,1%) received 1 st line treatment and 35 patients (25,9%) 2 nd line treatment with median time between the two treatment lines being 26.5 months (IQR: 7.8 - 40.8 months). Furthermore, 48.5%, 33.8%, 12.3%, 3.1% and 2.3% of the patients had Rai score 0, I, II, III, IV respectively. The median mRNA expression of RRM1 was 0.04 (IQR: 0 - 0.09) and of RRM2 was 0.01 (IQR: 0 - 0.1). RRM1 mRNA expression was significantly higher in patients without anemia (p=.025) and without lymphadenopathy (p=.002). Higher values of ESR (r=-.30; p=.028), LDH (r=-.20; p=.026) and Rai score (r=-.18; p=.037) were associated with lower expression of RRM1 mRNA. In addition, TP53 gene deletion detected by FISH was associated with higher RRM1 mRNA expression (p=.036). Significantly higher RRM2 mRNA expression was reported in patients without lymphadenopathy (p=.021) and Rai score 0 (p=.003). Moreover, higher was the expression of RRM2 mRNA in cases with Trisomy 12 (p=.050). In samples collected before treatment, higher values of RRM1 mRNA expression were statistically significantly associated with lower RAI score (r=-.30; p=.005) and longer time periods between the first two lines of treatment (r=.95; p=.050). Western blot analysis confirmed detection of RRM1 protein but statistical correlation was not carried out due to lack of material from the whole group of patients. Conclusion For the first time, mRNA expression of RRM1 and RRM2 is studied in patients with CLL. These results show RNR involvement in the pathophysiology of CLL. RRM1 and RRM2 mRNA higher expression found in 17p deletion and trisomy 12 cases respectively may be consistent with the existence of a methylation-depended mechanism proposed by other studies. Therefore, these results demonstrate RNR's potential role as a prognostic factor, and make it a probable therapeutic target. A study including a larger number of cases could further confirm our results. Figure 1 Figure 1. Disclosures Kyrtsonis: Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene/Genesis Pharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Honoraria; Sanofi: Membership on an entity's Board of Directors or advisory committees. Panagiotidis: Abbvie: Research Funding; Pfizer: Research Funding; Janssen: Research Funding; Sanofi: Research Funding; Novartis: Research Funding; Takeda: Research Funding; Sandoz: Research Funding; Bristol-Myers Squibb: Research Funding; Roche: Research Funding; Astellas: Research Funding. Viniou: Sandoz: Research Funding; Takeda: Research Funding; Novartis: Honoraria, Research Funding; Sanofi: Research Funding; Janssen: Honoraria, Research Funding; Pfizer: Research Funding; Abbvie: Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Roche: Research Funding; Astellas: Research Funding; Celgene: Research Funding.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1772-1772
Author(s):  
Daniel L. Van Dyke ◽  
Jeannette G Rustin ◽  
Stephanie A. Smoley ◽  
Jeanette Eckel Passow ◽  
Ruchi G. Sharma ◽  
...  

Abstract Abstract 1772 Background: B-Chronic Lymphocytic Leukemia (CLL) is notorious for its complex and heterogeneous clinical behavior pattern in a given patient. Panels of prognostic predictors in CLL can be complex but in general have been found to be useful in counseling a given patient. The current most powerful prognostic parameters for disease progression potential are related to leukemic B cell genetic features. Using fluorescent in situ hybridization (FISH) panels, we and others have found a hierarchy of clinical outcome with 17p- and 11q- most aggressive. The limitation of the FISH panel is that while it detects the most common recurring defects, it does not evaluate the global genomic status of the leukemia in terms of less common genetic changes or in terms of genetic complexity. Array comparative genomic hybridization (CGH) has shown that CLL B cells frequently do exhibit greater genetic complexity than is detected by the FISH panel. To further assess the relationship of genomic defects in CLL to disease outcome, we used CGH for genetic analysis of the leukemic cells at or close to the diagnosis in two cohorts of CLL patients who had either stable or progressive disease. Methods: We obtained leukemic B cells from patients retrospectively identified as “progressive” (n=47) or “stable” (n=21) CLL patients. The CLL patients had given informed consent to have tissue stored and had robust long term clinical outcome available on our Mayo Clinic CLL Tissue Bank and clinical database. Patients were selected based on whether they were stable as defined by no need for therapy after 5 years from diagnosis, or progressive as defined by requiring therapy within 2 years of the actual CLL diagnosis. All progressive patients had leukemic blood cells sampled within 12 months of diagnosis and prior to treatment. All stable patients had blood cells sampled within 24 months of diagnosis. DNA was extracted and then used for global genomic defect detection using a custom high density 2 × 400k oligonucleotide CGH chip (Agilent). Copy number abnormalities (CNA) and copy number variants (CNV) were assessed. CNA were studied for relationship to clinical outcome for the two cohorts of CLL patients.and CNV were excluded from further analysis. Results: The median age was 61 (range 42–81) years in progressive and 67 (range 42–80) in stable patients. Males comprised 77% of the progressive and 57% of the stable patients. CGH was successful in all 68 patients. FISH and CGH were discordant in 8 cases, all with <20% abnormal cells by FISH. Total number of CNA (excluding known benign variants and immunoglobulin rearrangements) was 816, with 597 in progressive (mean 12.7) and 219 in stable patients (mean 10.4). Two stable patients had a normal CGH result. Progressive patients included 15 of 16 trisomy 12, all 4 deletion 17p, and 10 of 11 deletion 11q abnormalities by CGH. Deletion 13q was observed in 39 (83%) progressive and 15 (71%) stable patients, with Rb1 deletion in 11 (23%) progressive and 4 (19%) stable patients. Remarkably, trisomy 18 (2 patients), trisomy 19 (4 patients), and trisomy 21 (1of 2 patients) were observed by CGH in association with trisomy 12. Other recurrent CNA were del(3)(q22q22) in 2 progressive and 1 stable patient and dup(8)(q24.3q24.3) plus dup(11)(p15.4p15.5) in 3 progressive patients; one progressive patient had the dup(8q) without dup (11p). None of the dup(8q) or dup(11p) patients exhibited 11q-, 17p- or +12 defects. Cytogenetic complexity (measured by number of CNA) was greater in progressive than stable patients (p=0.03; odds ratio 1.196), although there was substantial overlap between the groups (range 6–28 CNA in progressive and 5–18 in stable patients). The number of CNA tended to be higher in the presence of 11q- (8–16 CNA) and trisomy 12 (7–21 CNA), and especially 17p- (13–28 CNA). Conclusions: CGH and FISH were comparable for the FISH probes tested. CGH revealed that deletion breakpoints were highly variable around the regions targeted by the FISH probes. That trisomy 18, 19, and 21 were confined to the trisomy 12 patients suggests a different mechanism of genetic instability underlying trisomy 12 in CLL. Trisomy 12, deletion 11q and deleton 17p were confined almost exclusively to patients with progressive disease. Likewise, 3 other recurrent CNA (3q-, 8p dup and 11p dup) were over-represented in progressive disease, may comprise high risk genetic defects, and offer new targets for understanding genetic pathways in CLL. Disclosures: Kay: Biothera: Research Funding; Clegene: Research Funding; Cephalon: Research Funding; Genentech: Research Funding; Glaxo Smith Kline: Research Funding; Hospira: Research Funding; Novartis: Research Funding; Supergen: Research Funding; Calistoga: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Emergent Biosolutions (Formerly Trubion): Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3741-3741
Author(s):  
Thimali Ranaweera Arachchige ◽  
Antoine Diep ◽  
Ambroise David ◽  
Melchior Le Mene ◽  
Virginie Eclache ◽  
...  

Abstract Patients with chronic lymphocytic leukemia (CLL) are prone to infectious complications, including Ears, Nose and Throat (ENT) infections due to the humoral immunodepression and/or to the immunosuppression related to the therapy. However, specific CLL infiltration in non-lymphoid regions of the head and neck causing ENT symptoms but unrelated to an infection is not well described. Extra-nodal localizations of CLL cells, including involvement of the mucosa of the rhinopharynx is uncommon and poorly reported. Here, we retrospectively analyzed the clinical, histopathologic and molecular features of 25 CLL patients with specific head and neck involvement. To date, this is the largest cohort reporting this new entity of CLL also named Nasal Associated Lymphoid Tissue (NALT) CLL. All patients had proven CLL prior to symptoms. Median time between ENT manifestation and CLL was 3 years [1-11 years]. Symptoms included chronic coughing (44%), antero-posterior nasal discharge (44%), nasal congestion (33%) and pharyngitidis (33%). ENT examination evidenced cervical lymphadenopathies in 68 % of cases, a granular aspect of the mucosa of the pharynx in 56%, enlarged tonsil (37%) or adenoids (37%). All patients underwent a biopsy of the mucosa of the nose or the throat. Histology and immunochemistry analysis demonstrated an infiltration of small lymphocytes CD20+, CD5+ and CD23+, consistent with a phenotype of CLL. The infiltration was diffuse in 50% of biopsies and perivascular in 38%. Patients with NALT-CLL had a poor prognosis: the majority was IGHV unmutated (n=18/25, 72%). Furthermore, they all required a treatment according to IWCLL criteria few time after the first ENT symptoms (median time 2 years), indicating that NALT-CLL is associated with a more progressive disease. To characterize the genetic background of NALT-CLL, we analyzed the cytogenetic data and NGS sequencing of 13 CLL-associated mutations from peripheral CLL cells. The karyotype was normal in only 2/24 cases (8%) and complex (&gt;3 abnormalities) in 5/24 cases (20%). Half of the patients had a trisomy 12(12/24; 50%), while 13q, 17p and 11q deletions were found in 29%, 8% and 4% respectively. Eleven patients harbored one mutation (44%) while 9 patients had 2 to 5. Mutation of the NOTCH1 pathway was found in half of the cases (11/25 NOTCH1 and 2/25 FBXW7 mutated cases). TP53 and SF3B1 mutations occurred respectively in 20% (5/25 cases) and in 12% (3/25 cases). To gain insight into the molecular mechanism associated with involvement of the rhinopahrynx, we studied the expression of 70 genes related to cell migration and cell adhesion pathways using a qPCR array in the peripheral CLL cells of patients with NALT (n=4) compare to no NALT-CLL (n=4). Genes significantly up regulated with a fold change &gt;2 included the chemokine receptors CCR7 (p=0.05) and CCR5 (p=0.04), the receptor involved in leukocyte trafficking CXCR3 (p=0.01) or the chemoattractant chemokine-like factor CKLF. By targeted qPCR, we confirmed the up regulation of CCR7 (p=0.002), CXCR3 (p=0.04) and CCR5 (p=0.03) in the cohort NALT-CLL patient (n=25) as compared to 20 age-matched CLL patients without head and neck symptoms (77% with unmutated IGHV, 30% with NOTCH1 mutation and 30% with trisomy 12). Up regulation of those targets was independent of the presence of NOTCH1/trisomy12 aberration or of the IGHV mutation status. These results suggest an increased migratory capacity of the leukemic CLL cells into the rhynopharynx mucosa related to a higher expression of these receptors involved in cell trafficking and migration. In line with these results, immunohistochemistry analysis of 5 patients with nasal involvement showed a strong staining of the CCR7 marker on the membrane of CLL cells infiltrating the mucosa. Interestingly, the staining of CCL21, the cognate ligand of CCR7, was positive in the vessels of the mucosa, suggesting that the recruitment and the transendothelial migration of CLL cells into the mucosa occur through a local secretion of CCL21 by the vessels. In summary, we report here a new presentation of CLL associated with symptomatic and specific ENT localization. CLL cells are predominantly IGHV unmutated, harbor NOTCH1 mutation and/or trisomy12 and show a higher expression of the chemokine receptors CCR7, CCR5 and CXCR3. We are currently studying the expression of those receptors by flow cytometry and the enhanced migratory capacity toward CCL21 through an in vitro chemotaxis assay. Disclosures Letestu: AbbVie: Research Funding, Speakers Bureau; Roche: Speakers Bureau; Janssen: Research Funding, Speakers Bureau. Cymbalista: Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees; ASTRA ZENECA: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Lilly-LOXO: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3907-3907
Author(s):  
Paolo Strati ◽  
Lynne V. Abruzzo ◽  
William Wierda ◽  
Susan Lerner ◽  
Susan M. O'Brien ◽  
...  

Abstract Abstract 3907 Cytogenetic abnormalities are among the most important predictors of clinical course and response to therapy in patients (pts) with chronic lymphocytic leukemia (CLL). Conventional chromosome banding (CBA) and fluorescence in situ hybridization (FISH) analyses detect abnormalities in 40–50% and 80% of pts, respectively. Trisomy 12 (+12), observed in ∼20% of CLL pts by FISH, is associated with atypical morphology and immunophenotype, and a more aggressive clinical course. We, therefore, review the clinical characteristics and outcome of 312 CLL pts with +12 evaluated at our center between 1988 and 2011. FISH analysis for common abnormalities associated with CLL was performed on interphase nuclei obtained from cultured bone marrow cells using a multi-color probe panel designed to detect deletions of 11q22.3 (ATM), 13q14.3 (D13S319), 13q34 (LAMP1), 17p13.1 (TP53) and trisomy 12 (12p11.1-q11) (Abbott Molecular, Abbott Park, IL). Survival curves were calculated using Kaplan-Meier estimates and compared using the log-rank test. Differences were considered significant for p < 0.05. Patient characteristics at diagnosis are presented in Table 1. Of 215 pts assessed by both CBA and FISH, 105 were positive for +12 by both analyses and 110 were positive only by FISH. By CBA (112 pts, including 7 assessed only by CBA), +12 was the sole abnormality in 52 pts (47%); +12 was associated with +19 in 17 pts (16%), with del(14q) in 9 pts (8%), with +18 in 8 pts (7%), with +8 in 3 pts (3%), with del(13q) in 3 pts (3%), with t(14;19)(q32;q13) in 3 pts (3%) and with other abnormalities in 17 pts (13%). By FISH (287 pts), +12 was the sole abnormality in 225 pts (78%) and was associated with del(13q) in 62 pts (22%). The median number of interphase nuclei positive for +12 by FISH was 47% (range, 5–93%). One-hundred-eighty-seven pts (60%) needed treatment, with a median Time-To-Treatment (TTT) of 46 months (range, 35–56). The TTT was significantly shorter in pts with Rai stage III-IV disease, splenomegaly, lymphadenopathy, B2m > 4 mg/L, CD38+, ZAP70+, +12 detected by both CBA and FISH, and +12 associated with del(14q) or t(14;19). All 187 pts with progressive disease received treatment: 105 with an FCR-based regimen, 28 with rituximab(R)-based therapy (R+ GM-CSF or R+ methylprednisolone), and 28 with investigational drugs (Lenalidomide, R+ lenalidomide, GS101, or Ibrutinib). Overall response rate was 98%, 89% and 96%, respectively, whereas complete remission rate was 87%, 11% and 36%, respectively. Fifty-five pts failed first-line treatment; their median Failure-Free Survival (FFS) was 27 months (range, 0–87). The FFS was significantly longer in pts who received FCR-based regimens (p<0.001)(Fig 1). The median overall survival (OS) has not been reached, and only 33 pts have died. The OS was significantly shorter in pts older than 65 years, with ALC > 30,000, and with a median +12 positivity in >30% of interphase nuclei by FISH. A trend toward longer OS was observed for pts with +12 associated with +19 (p=0.07). Richter's Syndrome (RS) and second malignancies (SM) were the leading causes of death (5 and 13 of 33 deaths, respectively). RS was reported in 12 pts (4%), after a median time of 36 months from diagnosis. SM was reported in 31 pts (10%), after a median time of 30 months from diagnosis. At the time of diagnosis of SM, 13 patients had received a therapy for CLL and 18 were untreated. In conclusion, pts with CLL and +12 have unique laboratory and clinical features. A high proportion develops progressive disease and requires treatment. Among available therapies, FCR-based regimens are associated with a longer FFS. A high rate of SM is observed in pts with +12, including in pts who have not received prior treatment Disclosures: Wierda: Abbott Laboratories: Research Funding. O'Brien:Avila: Research Funding; Bayer: Consultancy; Bristol-Myers Squibb: Research Funding; Gilead Sciences: Consultancy, Research Funding; Celgene: Consultancy; Cephalon: Consultancy; CII Global Research Foundation: Membership on an entity's Board of Directors or advisory committees; Genentech BioOncology: Research Funding; Genzyme: Consultancy; GlaxoSmithKline: Consultancy; MorphoSys: Consultancy; Novartis: Consultancy; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Consultancy; Seattle Genetics, Inc.: Consultancy; Sigma Tau Pharmaceuticals: Consultancy; Talon: Research Funding; The Medal Group: Speakers Bureau.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2939-2939 ◽  
Author(s):  
Constantine Tam ◽  
Mary Ann Anderson ◽  
David S. Ritchie ◽  
E. Henry Januszewicz ◽  
Dennis Carney ◽  
...  

Abstract Introduction Targeted inhibitors of BTK, PI3K or BCL-2 all induce durable responses in patients with chemotherapy-refractory CLL. In the case of the BTK inhibitor ibrutinib, two patterns of resistance have emerged: early (<12 - 24 months) progression with RichterÕs Syndrome (RS), and late progression with CLL often carrying BTK and/or PLCγ mutations. The survival of patients with disease progression after ibrutinib is reported to be poor, particularly for those with RS (median overall survival (OS) 2.6 - 3.5 months)(Blood 2015:2062, JAMA Oncol 2015:80). There are no available data in the context of venetoclax failure. Methods We analyzed our institutional experiences with 70 patients with relapsed / refractory CLL enrolled across 3 venetoclax studies between 2011 and 2015 (2 single agent, 1 rituximab combination). Twenty-eight patients (40%) ceased venetoclax for reasons other than voluntary drug hold after achieving complete remission; these patients had received a median 7.5 (range, 1 - 38) months of venetoclax therapy prior to cessation. Results Of 28 patients, 7 (25%) had CLL progression, 16 (57%) developed RS (3 Hodgkin, 13 DLBCL), and 5 (18%) ceased for other reasons. Patients who ceased therapy typically had high-risk disease characteristics including del(17p)/TP53 mutation or complex cytogenetics in 70%, unmutated IgHV in 88%, and a median of 4 (range 1 - 12) prior therapies before venetoclax. After a median survivor follow-up of 12.5 months (range 0 - 34), the median post-progression survival of patients who progressed with CLL and RS were: not reached (1 year OS 69%) and 12 months, respectively (p=0.88, Figure). Post-progression survival did not statistically differ by any of the following factors: response to venetoclax, progression on venetoclax before or after 12 months, cytogenetic risk, or the number of prior therapies (all p-values >0.18). Of the 7 patients with CLL progression, 5 remain alive on next-line ibrutinib (n=4) or corticosteroids (1). Of the 16 patients with RS, 15 received salvage therapy; R-CHOP (n=6) and R-ICE (3) being the most commonly used regimens. 4 received consolidation with stem cell transplantation. One allogeneic stem cell recipient died at 12 months from transplant-related complications, and the other remains alive and free of disease at 34 months. Both autologous transplant recipients have relapsed with CLL and were successful salvaged with BTK inhibitors. Conclusion Failure of venetoclax does not automatically portend a poor prognosis. The survival of patients who progress with CLL or RS on venetoclax therapy may be superior to that reported for BTK inhibitors. Figure 1. Figure 1. Disclosures Tam: Janssen: Consultancy, Honoraria, Research Funding. Off Label Use: Venetoclax is not licensed for treatment of CLL. Roberts:AbbVie and Genentech: Research Funding; Walter and Eliza Hall Institute of Medical Research: Employment. Seymour:Genentech, Inc.: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Speakers Bureau; Phebra: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding, Speakers Bureau; Infinity: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 4677-4677
Author(s):  
Julia E. Wiedmeier ◽  
Chantal McCabe ◽  
Daniel R. O'Brien ◽  
Nicholas J. Boddicker ◽  
Rosalie Griffin Waller ◽  
...  

Abstract Introduction: Chronic lymphocytic leukemia (CLL) is characterized by multiple copy number alterations (CNA) and mutations that are central to disease pathogenesis, prognosis, risk-stratification, and identification of response or resistance to therapies. Fluorescence in situ hybridization (FISH) is gold standard in the clinical laboratory for detecting prognostic CNAs in CLL (e.g. deletion 17p13 (del(17p), deletion 11q23 (del(11q), deletion 13q14 (del(13q), and trisomy 12). Most clinical FISH assays have high specificity and sensitivity, but the technique can detect a limited number of alterations per assay. Importantly, next-generation sequencing (NGS) techniques have become more readily available for clinical applications and are increasingly being used for screening not only mutations, but also copy number abnormalities in multiple genes and chromosomal regions of interest in hematologic malignancies. Here, we evaluated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) using a custom targeted NGS assay for detecting common prognostic chromosomal alterations in CLL and high-count monoclonal B-cell lymphocytosis (MBL), the precursor to CLL. Methods : We designed a SureSelect DNA targeted sequencing panel, covering all exons of 59 recurrently CLL mutated genes and additional amplicons across regions affected by clinically relevant CNAs. All CLL (N=534) and MBL (N=162) patients had pre-treatment peripheral blood mononuclear cells (PBMC) collected within two years of diagnosis. DNA was extracted in cases with purity &gt;80% of CD5+/CD19+ cells. Clinical FISH data was available within 100 days of NGS in all untreated CLL and MBL cases. PatternCNV was used to detect clinically relevant CNAs in chromosomes 11, 12, 13 and 17. We performed a principal component analysis on the CNA calls, excluding chromosomes 11, 12, 13, and 17 to identify clusters of samples. Each cluster was then independently rerun with PatternCNV and the results from chromosomes 11, 12, 13, and 17 were extracted and further analyzed. We excluded samples with low tumor metrics identified by FISH (less than 20% of cells with del(17p), del(11q), trisomy 12 and del(13q)). Results: We sequenced a total of 696 patients of whom 162 were MBL and 534 were untreated CLL. The most commonly mutated genes were NOTCH1 (11.0%), TP53 (8.7%), SF3B1 (7.7%), ATM (4.1%), and CHD2 (3.8%). Based on CNA analyses from the NGS data, we identified 59 (9.1%) individuals with del(17p), 88 (13.4%) individuals with del(11q), 128 (20.0%) individuals with trisomy 12, and 329 (53.0%) individuals with del(13q). All 696 individuals had FISH panels conducted, with 39 (5.6%) individuals with del(17p), 68 (9.8%) individuals with (11q), 119 (17.1%) with trisomy 12, and 295 (42.4%) with del(13q). When we compared our CNA analyses with the FISH data, we found high concordance 95.0% for del(17p), 92.7% del(11p), 94.3% for trisomy 12, and 88.2% for del(13q). For del(17p) we found a sensitivity of 93.9%, specificity of 95.4%, PPV of 52.5%, and NPV of 99.7%. Del(11q) revealed a sensitivity of 88.1%, specificity of 94.0%, PPV of 59.1%, and NPV 98.8%. We found a sensitivity of 93.8%, specificity of 95.6%, PPV 82.0%, and NPV of 98.6% for trisomy 12 and for del(13q) we found a sensitivity of 92.6%, specificity of 90.9%, PPV of 91.7%, and NPV of 93.8%. We found lower PPVs in del(17p) and del(11q) likely due to lower prevalence of these chromosomal abnormalities. Conclusion: Here we show a high sensitivity, specificity, and NPV when comparing targeted sequencing with FISH. FISH panel testing is widely used in clinical practice to characterize highly prognostic chromosomal abnormalities in CLL. Comprehensive genetic profiling with NGS has become increasingly important in the work up of hematologic malignancies and provides additional prognostic and predictive information, including clinically relevant mutations such as TP53, SF3B1, and NOTCH1, tumor mutation load and mutations associated with resistance to chemo-immunotherapy and targeted therapies, such as BTK or BCL2 inhibitors, that FISH cannot offer. We show that NGS can infer clinically relevant CNA in cases without FISH testing while also providing additional clinically relevant information. Figure 1 Figure 1. Disclosures Cerhan: Regeneron Genetics Center: Other: Research Collaboration; Celgene/BMS: Other: Connect Lymphoma Scientific Steering Committee, Research Funding; NanoString: Research Funding; Genentech: Research Funding. Parikh: Pharmacyclics, MorphoSys, Janssen, AstraZeneca, TG Therapeutics, Bristol Myers Squibb, Merck, AbbVie, and Ascentage Pharma: Research Funding; Pharmacyclics, AstraZeneca, Genentech, Gilead, GlaxoSmithKline, Verastem Oncology, and AbbVie: Membership on an entity's Board of Directors or advisory committees. Kay: Genentech: Research Funding; MEI Pharma: Research Funding; Sunesis: Research Funding; Acerta Pharma: Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Bristol Meyer Squib: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Tolero Pharmaceuticals: Research Funding; Rigel: Membership on an entity's Board of Directors or advisory committees; Morpho-sys: Membership on an entity's Board of Directors or advisory committees; CytomX Therapeutics: Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Research Funding; Juno Therapeutics: Membership on an entity's Board of Directors or advisory committees; Agios Pharm: Membership on an entity's Board of Directors or advisory committees; Oncotracker: Membership on an entity's Board of Directors or advisory committees; Dava Oncology: Membership on an entity's Board of Directors or advisory committees; Targeted Oncology: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Behring: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 30-31
Author(s):  
Hanyin Wang ◽  
Shulan Tian ◽  
Qing Zhao ◽  
Wendy Blumenschein ◽  
Jennifer H. Yearley ◽  
...  

Introduction: Richter's syndrome (RS) represents transformation of chronic lymphocytic leukemia (CLL) into a highly aggressive lymphoma with dismal prognosis. Transcriptomic alterations have been described in CLL but most studies focused on peripheral blood samples with minimal data on RS-involved tissue. Moreover, transcriptomic features of RS have not been well defined in the era of CLL novel therapies. In this study we investigated transcriptomic profiles of CLL/RS-involved nodal tissue using samples from a clinical trial cohort of refractory CLL and RS patients treated with Pembrolizumab (NCT02332980). Methods: Nodal samples from 9 RS and 4 CLL patients in MC1485 trial cohort were reviewed and classified as previously published (Ding et al, Blood 2017). All samples were collected prior to Pembrolizumab treatment. Targeted gene expression profiling of 789 immune-related genes were performed on FFPE nodal samples using Nanostring nCounter® Analysis System (NanoString Technologies, Seattle, WA). Differential expression analysis was performed using NanoStringDiff. Genes with 2 fold-change in expression with a false-discovery rate less than 5% were considered differentially expressed. Results: The details for the therapy history of this cohort were illustrated in Figure 1a. All patients exposed to prior ibrutinib before the tissue biopsy had developed clinical progression while receiving ibrutinib. Unsupervised hierarchical clustering using the 300 most variable genes in expression revealed two clusters: C1 and C2 (Figure 1b). C1 included 4 RS and 3 CLL treated with prior chemotherapy without prior ibrutinib, and 1 RS treated with prior ibrutinib. C2 included 1 CLL and 3 RS received prior ibrutinib, and 1 RS treated with chemotherapy. The segregation of gene expression profiles in samples was largely driven by recent exposure to ibrutinib. In C1 cluster (majority had no prior ibrutinb), RS and CLL samples were clearly separated into two subgroups (Figure 1b). In C2 cluster, CLL 8 treated with ibrutinib showed more similarity in gene expression to RS, than to other CLL samples treated with chemotherapy. In comparison of C2 to C1, we identified 71 differentially expressed genes, of which 34 genes were downregulated and 37 were upregulated in C2. Among the upregulated genes in C2 (majority had prior ibrutinib) are known immune modulating genes including LILRA6, FCGR3A, IL-10, CD163, CD14, IL-2RB (figure 1c). Downregulated genes in C2 are involved in B cell activation including CD40LG, CD22, CD79A, MS4A1 (CD20), and LTB, reflecting the expected biological effect of ibrutinib in reducing B cell activation. Among the 9 RS samples, we compared gene profiles between the two groups of RS with or without prior ibrutinib therapy. 38 downregulated genes and 10 upregulated genes were found in the 4 RS treated with ibrutinib in comparison with 5 RS treated with chemotherapy. The top upregulated genes in the ibrutinib-exposed group included PTHLH, S100A8, IGSF3, TERT, and PRKCB, while the downregulated genes in these samples included MS4A1, LTB and CD38 (figure 1d). In order to delineate the differences of RS vs CLL, we compared gene expression profiles between 5 RS samples and 3 CLL samples that were treated with only chemotherapy. RS samples showed significant upregulation of 129 genes and downregulation of 7 genes. Among the most significantly upregulated genes are multiple genes involved in monocyte and myeloid lineage regulation including TNFSF13, S100A9, FCN1, LGALS2, CD14, FCGR2A, SERPINA1, and LILRB3. Conclusion: Our study indicates that ibrutinib-resistant, RS-involved tissues are characterized by downregulation of genes in B cell activation, but with PRKCB and TERT upregulation. Furthermore, RS-involved nodal tissues display the increased expression of genes involved in myeloid/monocytic regulation in comparison with CLL-involved nodal tissues. These findings implicate that differential therapies for RS and CLL patients need to be adopted based on their prior therapy and gene expression signatures. Studies using large sample size will be needed to verify this hypothesis. Figure Disclosures Zhao: Merck: Current Employment. Blumenschein:Merck: Current Employment. Yearley:Merck: Current Employment. Wang:Novartis: Research Funding; Incyte: Research Funding; Innocare: Research Funding. Parikh:Verastem Oncology: Honoraria; GlaxoSmithKline: Honoraria; Pharmacyclics: Honoraria, Research Funding; MorphoSys: Research Funding; Ascentage Pharma: Research Funding; Genentech: Honoraria; AbbVie: Honoraria, Research Funding; Merck: Research Funding; TG Therapeutics: Research Funding; AstraZeneca: Honoraria, Research Funding; Janssen: Honoraria, Research Funding. Kenderian:Sunesis: Research Funding; MorphoSys: Research Funding; Humanigen: Consultancy, Patents & Royalties, Research Funding; Gilead: Research Funding; BMS: Research Funding; Tolero: Research Funding; Lentigen: Research Funding; Juno: Research Funding; Mettaforge: Patents & Royalties; Torque: Consultancy; Kite: Research Funding; Novartis: Patents & Royalties, Research Funding. Kay:Astra Zeneca: Membership on an entity's Board of Directors or advisory committees; Acerta Pharma: Research Funding; Juno Theraputics: Membership on an entity's Board of Directors or advisory committees; Dava Oncology: Membership on an entity's Board of Directors or advisory committees; Oncotracker: Membership on an entity's Board of Directors or advisory committees; Sunesis: Research Funding; MEI Pharma: Research Funding; Agios Pharma: Membership on an entity's Board of Directors or advisory committees; Bristol Meyer Squib: Membership on an entity's Board of Directors or advisory committees, Research Funding; Tolero Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Research Funding; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Rigel: Membership on an entity's Board of Directors or advisory committees; Morpho-sys: Membership on an entity's Board of Directors or advisory committees; Cytomx: Membership on an entity's Board of Directors or advisory committees. Braggio:DASA: Consultancy; Bayer: Other: Stock Owner; Acerta Pharma: Research Funding. Ding:DTRM: Research Funding; Astra Zeneca: Research Funding; Abbvie: Research Funding; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; Octapharma: Membership on an entity's Board of Directors or advisory committees; MEI Pharma: Membership on an entity's Board of Directors or advisory committees; alexion: Membership on an entity's Board of Directors or advisory committees; Beigene: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5468-5468
Author(s):  
Shuo Ma ◽  
Rebecca J Chan ◽  
Lin Gu ◽  
Guan Xing ◽  
Nishan Rajakumaraswamy ◽  
...  

Introduction: Idelalisib (IDELA) is the first-in-class PI3Kδ inhibitor and is approved as a monotherapy for relapsed or refractory (R/R) follicular lymphoma and in combination with rituximab for R/R chronic lymphocytic leukemia (CLL). We previously evaluated IDELA treatment interruption as a mechanism to mitigate treatment-emergent adverse events (TEAEs) and found that limited interruption with clinically appropriate re-challenging resulted in superior clinical outcomes. These findings did not comprehensively address the potential confound of interruptions inherently being associated with longer duration of therapy (DoT). Furthermore, the compound effect of IDELA dose reduction together with treatment interruption on IDELA efficacy was not assessed. Objectives: 1) To evaluate whether the benefit of IDELA interruption is retained in patients on therapy >180 days, a duration previously found to be associated with longer overall survival among patients who discontinued IDELA due to an AE; and 2) To compare clinical outcomes of patients who reduced IDELA dosing in addition to interrupting IDELA with those of patients who interrupted IDELA without additional dose reduction. Methods: Using data from Gilead-sponsored trials of patients with R/R indolent non-Hodgkin's lymphoma (iNHL) treated with IDELA monotherapy (N=125, Gopal et al., N. Engl. J. Med., 2014) or with R/R CLL treated with IDELA + anti-CD20 (N=110, Furman et al., N. Engl. J. Med., 2014; and N=173, Jones et al., Lancet Haematol., 2017), DoT, progression-free survival (PFS), and overall survival (OS) were compared between patients on IDELA therapy >180 days with vs. without interruption and between patients who experienced Interruption and Dose Reduction (IDR) vs. patients who experienced Interruption but NoDose Reduction (INoDR) at any point during IDELA treatment. Interruption was defined as missing at least one IDELA treatment day due to an AE and dose reduction could have occurred before or after the first interruption. PFS and OS were estimated using the Kaplan-Meier method and were compared using a log-rank test. Results: Sixty-nine of 125 patients with R/R iNHL (55.2%) and 222 of 283 patients with R/R CLL (78.4%) remained on IDELA therapy >180 days with 29 (42.0%) and 103 (46.4%) of them, respectively, experiencing interruption on or after day 180 (Table 1). The proportions of patients with interruption before day 180 were similar within each of these populations. Among patients on therapy >180 days, those with treatment interruption on or after 180 days had a longer median (m) DOT than patients without interruption (Table 1). Both PFS and OS were longer in CLL patients who interrupted compared to those who did not interrupt (mPFS=28.9 mos. vs. 17.3 mos. and mOS=not reached [NR] vs. 40.4 mos. for with interruption vs. without interruption, respectively, Table 1 and Figure 1). In patients with iNHL, no difference was observed in PFS or OS between patients who interrupted vs. those who did not (Table 1). Of patients who experienced at least one AE-induced interruption at any point during IDELA therapy (n=63 iNHL and n=157 CLL), 47 iNHL patients (74.6%) and 84 CLL patients (53.5%) also had dose reduction. Two iNHL patients (1.6%) and 5 CLL patients (1.8%) had IDELA dose reduction but no interruption. Both iNHL and CLL patients with IDR experienced a similar PFS compared to patients with INoDR (mPFS=16.5 mos. vs. 14.2 mos. for iNHL and 21.8 mos. vs. 22.1 mos. for CLL with IDR vs. INoDR, respectively, Table 2). However, OS was longer in both iNHL and CLL patients with IDR compared to INoDR (mOS=61.2 mos. vs. 35.3 mos. for iNHL and NR vs. 42.4 mos. for CLL, respectively, Table 2; CLL patients shown in Figure 2). Discussion: IDELA treatment interruption is not associated with rapid clinical deterioration, as observed with some B-cell receptor signaling pathway inhibitors. No clear relationship between IDELA DoT and frequency of interruption was observed. When normalized for DoT >180 days, IDELA treatment interruption retained its clinical benefit in the CLL population. When utilized together with IDELA interruption, dose reduction did not lead to inferior clinical outcomes but instead extended OS in both iNHL and CLL populations. Adherence to treatment interruption and dose reduction guidance as outlined in the IDELA USPI may optimize IDELA tolerability and efficacy for patients with iNHL and CLL. Disclosures Ma: Janssen: Consultancy, Speakers Bureau; Pharmacyclics: Consultancy, Research Funding, Speakers Bureau; Gilead: Research Funding; Abbvie: Research Funding; Juno: Research Funding; Incyte: Research Funding; Xeme: Research Funding; Beigene: Research Funding; Novartis: Research Funding; Astra Zeneca: Consultancy, Research Funding, Speakers Bureau; Kite: Consultancy; Acerta: Research Funding; Bioverativ: Consultancy; Genentech: Consultancy. Chan:Gilead Sciences, Inc.: Employment, Equity Ownership. Gu:Gilead Sciences, Inc.: Employment. Xing:Gilead Sciences, Inc.: Employment. Rajakumaraswamy:Gilead Sciences, Inc.: Employment. Ruzicka:Gilead Sciences, Inc.: Employment. Wagner-Johnston:Gilead: Membership on an entity's Board of Directors or advisory committees; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees; Jannsen: Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 9-10
Author(s):  
Piers Blombery ◽  
Ella R Thompson ◽  
Xiangting Chen ◽  
Tamia Nguyen ◽  
Mary Ann Anderson ◽  
...  

Venetoclax (Ven) is an effective element of treatments for chronic lymphocytic leukemia (CLL) with high response rates observed in the upfront and relapsed/refractory (R/R) settings. In addition to inducing apoptosis in CLL cells, Ven also induces apoptosis within normal and malignant myeloid lineage populations (accounting for its efficacy in the treatment of acute myeloid leukemia). We investigated the effects of Ven outside the target tumor compartment in patients (pts) with CLL receiving long-term continuous Ven and make the novel observation of the development of BAX-mutated clonal hematopoiesis in this heavily pre-treated patient group. 92 pts with CLL receiving continuous non time-limited Ven have been treated at our institutions on clinical trials. Of these, 41 had sufficient (&gt;6 mo) follow up (median 70; range 14-95 mo) and suitable samples available for further analysis. 38/41 (93%) pts had received previous treatment with alkylators and/or fludarabine. In order to assess the non-CLL compartment in these 41 pts we identified those with peripheral blood or bone marrow aspirate samples taken during deep response to Ven demonstrating either minimal (&lt;5%) or no CLL involvement by flow cytometry (sensitivity 10-4). We initially performed unique molecular index (UMI)-based targeted next generation sequencing of apoptosis pathway genes as well a panel of 60 genes recurrently mutated in lymphoid and myeloid malignancy. From these 41 pts we identified mutations in the apoptosis effector BAX in samples from 12 (29%). 20 different BAX mutations were observed across these 12 pts at variant allele frequencies (VAF) consistent with their occurrence in the non-CLL compartment. Mutations included frameshift, nonsense, canonical splice site and missense mutations occurring in key structural elements of BAX consistent with a loss-of-function mechanism (Fig 1A). Interestingly, an enrichment of missense and truncating mutations predicted to escape nonsense mediated decay were observed at the C-terminus of the BAX protein affecting the critical α9 helix. Mutations in this region have previously been shown in cell lines to cause aberrant intracellular BAX localization and abrogation of normal BAX function in apoptosis (Fresquet Blood 2014; Kuwana J Biol Chem 2020). For comparison, NGS targeted sequencing for BAX mutations was performed on samples from cohorts of pts with (i) myeloid or lymphoid malignancy (n=80) or (ii) R/R CLL treated with BTK inhibitors (n=15) after a similar extent of preceding chemotherapy. Neither of these cohorts had previous exposure to Ven. BAX mutations were not detected in any samples from these pts. Longitudinal sampling from pts on Ven harboring BAX mutations in the non-CLL compartment was performed to further understand compartment dynamics over time (in 9 pts over 21-93 months of follow up). Multiple pts demonstrated a progressive increase in VAF of single BAX mutations over time to become clonally dominant within the non-CLL compartment and with observed VAFs consistent with their presence in the myeloid compartment. Mutations in other genes implicated in clonal hematopoiesis and myeloid malignancy including ASXL1, DNMT3A, TET2, U2AF1 and ZRSR2 were also detected in these pts samples. Targeted amplicon single cell sequencing (Mission Bio) demonstrated the co-occurrence of clonally progressive BAX mutations within the same clones as mutations in DNMT3A and ASXL1 as well as the existence of further BAX mutations at low VAF outside these dominant clones which remained non-progressive over time (Fig 1B). In addition, fluctuations in the presence and VAF of myeloid-disease associated mutations was noted with Ven exposure. In aggregate these data are consistent with the existence of a selective pressure within the myeloid compartment of these pts and an interplay of BAX with other mutations in determining survival and enrichment of these clones over time with ongoing Ven therapy. In summary, we have observed the development of BAX-mutated clonal hematopoiesis specifically in pts with CLL treated with long-term Ven. These data are consistent with a multi-lineage pharmacological effect of Ven leading to a survival advantage for clones harboring BAX mutations within the myeloid compartment during chronic Ven exposure. Finally, our data support the further investigation of BAX mutations as a potential resistance mechanism in myeloid malignancies treated with Ven. Disclosures Blombery: Invivoscribe: Honoraria; Amgen: Consultancy; Janssen: Honoraria; Novartis: Consultancy. Anderson:Walter and Eliza Hall Institute: Patents & Royalties: milestone and royalty payments related to venetoclax.. Seymour:Celgene: Consultancy, Honoraria, Research Funding; F. Hoffmann-La Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding; AstraZeneca: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy; Mei Pharma: Consultancy, Honoraria; Morphosys: Consultancy, Honoraria; Nurix: Honoraria; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Tam:Janssen: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding; BeiGene: Honoraria. Huang:Servier: Research Funding; Walter and Eliza Hall Institute: Patents & Royalties: milestone and royalty payments related to venetoclax.; Genentech: Research Funding. Wei:Janssen: Honoraria, Other; Walter and Eliza Hall Institute: Patents & Royalties; AMGEN: Honoraria, Other: Advisory committee, Research Funding; Novartis: Honoraria, Research Funding, Speakers Bureau; Astellas: Honoraria, Other: Advisory committee; Pfizer: Honoraria, Other: Advisory committee; Macrogenics: Honoraria, Other: Advisory committee; Abbvie: Honoraria, Other: Advisory committee, Research Funding, Speakers Bureau; Genentech: Honoraria, Other: Advisory committee; Servier: Consultancy, Honoraria, Other: Advisory committee; Celgene: Honoraria, Other: Advisory committee, Speakers Bureau; Astra-Zeneca: Honoraria, Other: Advisory committee, Research Funding. Roberts:Janssen: Research Funding; Servier: Research Funding; AbbVie: Research Funding; Genentech: Patents & Royalties: for venetoclax to one of my employers (Walter & Eliza Hall Institute); I receive a share of these royalties.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3021-3021
Author(s):  
Gregory Lazarian ◽  
Floriane Theves ◽  
Myriam Hormi ◽  
Virginie Eclache ◽  
Stéphanie Poulain ◽  
...  

TP53 aberrations, including somatic mutations of TP53 gene or 17p deletion leading to the loss of the TP53 locus, are a major predictive factor of resistance to fludarabin based chemotherapy in chronic lymphocytic leukemia (CLL) and remain an adverse prognostic factor in the chemofree era. Therefore, detection of TP53 alteration before each new line of treatment is required for theranostic stratification. In order to better characterize the distribution and combination of the TP53 variants in CLL, we collected the TP53 sequencing data of 343 patients harboring TP53 mutations from centers of the French Innovative Leukemia Organization-CLL (FILO) and established a large data base of 573 TP53 mutations. Mutations were identified through NGS sequencing (covering exon 2 to 11) allowing the detection of low frequency variants down to 1% VAF. Several distinct low VAF mutations were orthogonally confirmed by digital PCR. TP53 variants were analyzed through UMD_TP53 data gathering 90 000 TP53 mutations from all type of cancers. IGHV mutational status and FISH analysis were available for 224 and 176 patients respectively. Using ACMG criteria from the UMD_TP53 database, we confirmed that 523 could be classified as pathogenic, 42 were likely pathogenic and 8 were VUS (Variants of Unknown Significance). As expected, the mutation distribution along the p53 protein exhibited a clustering of variants in the DNA binding domain of the protein. We also confirmed the presence of a specific hotspot at codon 234 (6%) which is noticeable in other CLL cohorts but absent in solid tumors. 431 TP53 variants led to the expression of a mutant protein whereas the remaining 142 led a TP53 null phenotype. For 8 patients without 17p deletion and a mutation VAF larger than 50%, SNP analysis indicate that these tumors had a copy number neutral loss of heterozygosis at 17p with a duplication of the mutant allele leading to homozygous mutations of TP53. When focusing on the allele burden of TP53 mutations, 264/573 (46%) variants had an allele frequency <10%. Even if they were predominantly found in polymutated cases, presence of only low VAF (<10%) mutations was evidenced in 74 (21%) patients (50 patients with a single TP53 mutation and 24 patients with more than one). All these cases would have been missed by conventional sequencing. Among the 343 patients, 113 (33%) were poly-mutated and harbored more than one pathogenic TP53 variants (2 to 11 variants per patient): 57 (16,7 %) had 2 variants, 32 (9,3%) had 3, 10 had 4 (3%) and 14 patients (4%) had 5 to 11 variants. Using both long range sequencing and in silico analysis, we could show that all these variants were distributed in different alleles supporting an important intratumoral heterogeneity and a strong selection for TP53 loss of function during tumor progression in these patients. Null variants were rarely found as single alteration: only 46 patients (13,4%) patients harbored a single null mutation. Null mutations were predominantly found in patients with multiclonal mutations (87% with 4 or more). Median size of variants significantly decreased with the number of mutations and most of low VAF (less than 10%) variants were found in multiclonal combinations. Multiclonal mutations were predominantly found in previously treated patients (41% treated versus 10 % untreated) but whether all these variants preceded treatment and were further selected is currently unknown. We observed that 71,5 % of patients were IGHV unmutated and multiclonal mutations were surprisingly more frequent in mutated IGHV cases than in unmutated ones. Only 50% of cases carried a 17p deletion, highlighting again the importance of testing for TP53 mutations in addition to FISH analysis. Presence or absence of 17p deletion was unrelated to the number of TP53 mutations. Taken together these observations suggest that the TP53 mutational landscape in CLL is very complex and can involve multiple mechanisms, converging to a total loss of TP53 function and tumor progression. NGS provides a powerful tool for detecting all these alterations including variants with low VAF and should become a standard for CLL screening prior to each line of treatment. Disclosures Leblond: Amgen: Honoraria, Speakers Bureau; Abbvie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Honoraria, Speakers Bureau; Astra Zeneca: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Letestu:Abbvie: Membership on an entity's Board of Directors or advisory committees, Other: speaker fee, expert contracts; Janssen: Membership on an entity's Board of Directors or advisory committees, Other: speaker fee, expert contracts; Roche: Membership on an entity's Board of Directors or advisory committees, Other: speaker fee, expert contracts; Alexion: Membership on an entity's Board of Directors or advisory committees, Other: speaker fee, expert contracts. Cymbalista:Abbvie: Honoraria; Roche: Research Funding; Sunesis: Research Funding; Gilead: Honoraria; Janssen: Honoraria; AstraZeneca: Honoraria.


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