High-Level Expression of ROR1 Associates with Early Disease Progression in Patients with Chronic Lymphocytic Leukemia

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1713-1713 ◽  
Author(s):  
Bing Cui ◽  
Liguang Chen ◽  
Laura Z. Rassenti ◽  
Emanuela M. Ghia ◽  
Jian Yu ◽  
...  

Abstract ROR1 is a type-1 tyrosine kinase-like orphan-receptor that ordinarily is expressed during embryogenesis, but that also is found on leukemia cells of patients (pts) with chronic lymphocytic leukemia (CLL). In prior studies we found ROR1 served as a receptor for Wnt5a, which could promote survival/growth of CLL cells. We found Wnt5a in the plasma is significantly higher in pts with CLL (3.2±1.6 ng/ml (mean ±S.D.), N = 36) than in healthy adults (0.14±0.16 ng/ml, N=14, p<0.01) and also may be elaborated by accessory cells in the CLL microenvironment. On the other hand, reducing expression of ROR1 on CLL cells via siRNA adversely affected leukemia-cell survival. We hypothesized that expression of ROR1 in CLL could play a role in the pathogenesis and/or progression of this disease. Early studies failed to define differences in the expression level of ROR1 on CLL cells of different pts in a small cohort. However, upon further analyses, we observed heterogeneity in the expression levels of ROR1 among samples of different pts in larger cohort. We investigated whether the level of ROR1 expression was associated with disease progression in a cohort of 1,568 CLL pts followed by CLL Research Corium (CRC). CLL samples were uniformly examined for the expression of ROR1 using the same preparation of an Alexa-647-conjugated anti-ROR1 mAb (4A5) and a standardized procedure by the CRC Tissue Core. We used 10 CLL cases, and tested ROR1 expression at 3 different time-points for each case. We found ROR1 expression was stable over time in all CLL cases. Then, we randomly segregated pt samples into either of two cohorts, one a training set of 797, and the other a validation set of 773 cases. For the 797 cases in the training dataset, we used the profile-likelihood method in a Cox regression model of treatment-free survival (TFS) from diagnosis to determine the optimal threshold level of ROR1 expressionthat could segregate pts into 2 subgroups. In the training cohort, 294 pts were stratified into a "ROR1-Low" subgroup and 503 pts were assigned to a "ROR1-High" subgroup, defining a threshold absolute mean fluorescence intensity of CLL cells stained for ROR1 of 29. The subgroup of pts in the ROR1- High subgroup had a median TFS of 6.0 years, whereas those pts in the ROR1-Low subgroup had a median TFS of 11.0 years. We applied this threshold to segregate the 773 samples of the validation cohort into ROR1-High and ROR1-Low subgroups. We found that high-level expression of ROR1retained its strong predictive adverse effect on TFS in this validation set. The subgroup of pts in the ROR1- High subgroup had a median TFS of 5.7 years, whereas those pts in the ROR1-Low subgroup had a median TFS of 11.8 years. The immunoglobulin heavy-chain variable region (IGHV) mutation status was known for 593 of the 797 samples in the training set (74%) and 586 of the 773 samples in the validation set (76%). A significantly lower percentage of the ROR1-Low cases (34%, or 69 of 203) used unmutated IGHV than did the ROR1-High cases (54%, or 209 of 390) (p<0.001). Nonetheless, using a multivariate Cox regression model with either a non-delayed entry or a delayed entry, we observed that high-level expression of ROR1 had predictive value for short TFS (non-delayed entry HR 1.4, p<0.05; delayed entry HR 1.9, p<0.001) even when the IGHV mutation status was taken into consideration (non-delayed entry HR 2.8, p<0.001; delayed entry HR 2.7, p<0.001). Taken together, this study demonstrates that there is heterogeneity in the expression of ROR1 on CLL B cells. Furthermore, we find that a high level expression of ROR1 is associated with early disease progression in pts with CLL. Table 1. Number of cases with high versus low ROR1 and mutated versus unmutated IGHV in the training and validation cohort Training Dataset Validation Dataset ROR1 MFI distribution (Median) 0~475 (35.5) 0~424(34.6) ROR1Low with Mutated IGHV 139 132 ROR1Low with Unmutated IGHV 64 84 ROR1High with Mutated IGHV 181 156 ROR1High with Unmutated IGHV 209 214 Total With Known IGHV Mutation Status 593 586 Disclosures Keating: Celgene Corp.: Consultancy; Glaxo-Smith-Kline Inc.: Other: Advisory board. Kay:Celgene Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Research Funding; Tolero Pharma: Research Funding; Genentech: Research Funding; Hospira: Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees, Research Funding. Byrd:Acerta Pharma BV: Research Funding. Gribben:Celgene: Consultancy, Honoraria; Janssen: Honoraria; Roche/Genentech: Honoraria; Pharmacyclics: Honoraria; Gilead: Honoraria. Kipps:Pharmacyclics Abbvie Celgene Genentech Astra Zeneca Gilead Sciences: Other: Advisor.

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3122-3122
Author(s):  
Elsa Sanchez-Lopez ◽  
Emanuela M. Ghia ◽  
Laura Antonucci ◽  
Laura Z. Rassenti ◽  
Yun Chen ◽  
...  

Abstract Recent studies have linked the autophagy adaptor p62/SQSTM1 to tumorigenesis via NRF2 signaling. Increased accumulation p62 is associated with disease progression in many cancers, however its expression in CLL has yet to be investigated. Importantly, p62, encoded by the SQSTM1 gene, mRNA expression and protein accumulation is regulated by nuclear factor-kappa B (NF-κB), a key transcription factor for CLL survival. In addition, CLL cells express receptor tyrosine kinase-like orphan receptor 1 (ROR1), an oncoembryonic protein that also is expressed on cancer cells of numerous malignancies, including those reported to show accumulation of p62. As in solid-tumor malignancies, high-level expression ROR1 in CLL is associated with enhanced disease-progression and shorter overall survival (Cui B, et al, Blood 25:2931, 2016). Furthermore, recent studies found that activation of Wnt5a-ROR1 cascade induces NF-κB activation and increased expression of NF-κB target genes in CLL (Chen, Y et al, submitted ASH Abstract, 2018). Additionally, CLL cells exhibit increased basal activation of nuclear factor erythroid 2-related factor 2 (NRF2), which supports antioxidant and detoxifying responses that enhance resistance to cytotoxic drugs. We hypothesized that high-level expression of ROR1 in CLL may influence the accumulation of p62, which in turn could lead to activation of NRF2-signaling to enhance CLL-cell survival and resistance to therapy. We found that CLL cells with high-level surface expression of ROR1 (ROR1HIGH) had significantly greater accumulation of p62 than ROR1LOW CLL cells (p=0.003). Elevated p62 accumulation was accompanied by enhanced protein and mRNA expression of NRF2 targets, including NQO1 (p=0.009), GPX2 (p=0.019), GSTM1 (p=0.001), SOD1 (p=0.001) and MDM2 (p=0.001) (n=6 ROR1LOW and n=13 ROR1HIGH). We analyzed published gene expression data (GSE13204, Kohlmann A, et al BJH 142:802, 2008), of 448 CLL cases. We designated CLL cells with expression levels of ROR1 above the medium (n=224) as ROR1HI and cases with ROR1 expression below the medium value as ROR1LO (n=224), We confirmed that SQSTM1 (p=0.01), NQO1 (p=0.0001) and HMOX1 (p=0.002) were significantly overexpressed in ROR1HI CLL patients. In addition, we segregated GSE13204 dataset into two groups: ROR1>90% (n=45), representing the 10% of patients who had CLL cells with highest levels of ROR1 mRNA, and ROR1<10% (n=45), representing the 10% of patients who had CLL cells with lowest levels of ROR1 mRNA. Consistently, SQSTM1 (p=0.009), NQO1 (p=0.02) and HMOX1 (p=0.008) were significantly overexpressed in ROR1>90%. We performed gene set enrichment analysis (GSEA) to investigate whether NRF2 inducible genes (Malhotra D, et al, Nucleic Acids Research 38(17):5718, 2010) were expressed at higher levels in ROR1HI or ROR1>90% compared with ROR1LO or ROR1<10% CLL. In both comparisons, the GSEA revealed that NRF2 inducible genes were enriched in CLL cells with high ROR1 mRNA (FDR q of 0.01 and 0.06, respectively). Collectively, these data indicate that p62-NRF2 cascade is upregulated in CLL cells with high expression of ROR1 and suggest that it may play a role in the enhanced proliferation observed in ROR1HIGH CLL cells. Similarly, ROR1HIGH CLL cells and MEC1-ROR1 CLL cell line that express high protein level of NQO1 were resistant to ABT-199 (p<0.05 and p<0.001 respectively). Such agent induces the accumulation of reactive oxygen species (ROS), which are detoxified by products of the NRF2-activated antioxidant response. The role of NQO1 in protection from cell death was confirmed using a specific pro-drug, designated as 29h, which becomes active after being metabolized by NQO1 (p<0.05). Furthermore, treatment with 29h overcame NQO1-mediated resistance to ABT-199 (venetoclax) (p<0.05), resulting in PARP cleavage and accumulation of cytoplasmic cytochrome C, markers of apoptosis. This study illustrates a previously unknown and intricate signaling network through which ROR1-NF-κB-p62-NRF2 cascade may enhance disease progression and resistance to therapy in CLL B cells that express high levels of ROR1. Disclosures Kipps: Genentech Inc: Consultancy, Research Funding; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; F. Hoffmann-La Roche Ltd: Consultancy, Research Funding; Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Verastem: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy; Verastem: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4274-4274
Author(s):  
Md Kamrul Hasan ◽  
Laura Z. Rassenti ◽  
George F. Widhopf II ◽  
Thomas J. Kipps

Chronic lymphocytic leukemia (CLL) cells recirculate between blood and lymphoid tissue compartments, where they receive growth/survival signals from accessory cells within the lymphoid-tissue microenvironment. Such trafficking requires leukemia cells to pass through endothelial barriers and to transverse the extracellular matrix (EM), a process that is facilitated by matrix metallopeptidases (MMP). We co-cultured CLL cells with marrow mesenchymal stromal cells (MSCs) at a physiologic oxygen tension (e.g., 5% O2 in N2). Under such conditions we found that MSCs could enhance leukemia-cell expression of MMP9, a 92 kDa type IV collagenase and key MMP involved in EM degradation. Unexpectedly, however, we found circulating CLL cells with high-level expression of the onco-embryonic protein, ROR1 (designated ROR1Pos), also had high-level expression of MMP9 despite not having immediate contact with such accessory cells. Moreover, we found that circulating ROR1Pos CLL (N = 12) had significantly greater levels of MMP9 than blood CLL cells with low-to-negligible levels of ROR1 (ROR1Neg CLL, N = 10) (P < 0.001). Short-term culture of ROR1Pos CLL in serum-free media significantly reduced their expressed levels of MMP9, unless we added exogenous Wnt5a, a non-canonical Wnt factor and ligand for ROR1 that we found expressed at significantly higher levels in the plasma of patients with CLL than in age-matched adults (Yu et al., J Clin Invest, 2015). Treatment of ROR1Pos CLL cells with Wnt5a enhanced their expression and release of MMP9 and their capacity to invade Matrigel in a Boyden-Chamber Assay; such effects could not be inhibited by inhibitors of B-cell receptor/chemokine signaling (e.g. Ibrutinib), but could be blocked by cirmtuzumab, a humanized mAb specific for ROR1 that can inhibit leukemia-cell ROR1-signaling in patients with CLL (Choi et al., Cell Stem Cell, 2018). Silencing expression of MMP9 with siRNA or treatment with a MMP9-specific inhibitor (CAS 1177749-58-4) could inhibit the capacity of Wnt5a to enhance the invasive capability of CLL cells, indicating that MMP9 plays a major role in facilitating CLL-cell invasiveness. Targeted siRNA-mediated silencing of cytoskeletal proteins HS1/cortactin, which complex with ROR1 in response to Wnt5a (Hasan et al., Leukemia, 2018; Hasan et al., Leukemia, 2017), also impaired the capacity of Wnt5a to enhance expression and release of MMP9 in ROR1Pos CLL. Collectively, these studies indicate that Wnt5a can induce ROR1-signaling leading to enhanced expression of MMP9, which can facilitate invasion of the EM. Moreover, inhibitors of ROR1 signaling, such as cirmtuzumab, can repress Wnt5a-induced CLL-cell expression of MMP9, potentially impairing the homing of ROR1Pos CLL to their protective niches within the lymphoid microenvironment. Disclosures Kipps: AstraZeneca, Inc.: Membership on an entity's Board of Directors or advisory committees; Verastem: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Genentech, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Velos-Bio: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; Jannsen Pharmaceutical Companies of Johnson & Johnson: Honoraria, Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2805-2805 ◽  
Author(s):  
Laura Z. Rassenti ◽  
Donna S. Neuberg ◽  
Michael J. Keating ◽  
John G. Gribben ◽  
Ian W. Flinn ◽  
...  

Abstract We performed immunophenotypic and IgVH mutation analyses on the chronic lymphocytic leukemia (CLL) cells of 307 patients for expression of CD38, ZAP-70, and IgVH mutation status to determine the relative strength of each in predicting the need for early treatment. For this we assessed the time from diagnosis to initial therapy for progressive and/or symptomatic disease. Patients confirmed to have remained untreated were censored for this endpoint. Expression of CD38 was defined as the proportion of CD38-stained CLL cells that had fluorescence intensity above a defined threshold. Similarly, cases were defined as ZAP-70+ when 20% or more of the ZAP-70-stained CLL cells had fluorescence intensity above a defined threshold, as described (NEJM351:893, 2004). CLL cells were classified as expressing mutated IgVH genes if they expressed IgVH with &lt;98% homology with a known germline IgVH gene. The median percentage of cells expressing CD38 in our cohort was 11.5% (range 0.1% to 99.5%). In patients with multiple samples, the CD38 expression level appeared constant over time, with a median S.D. of 0.8%. We defined patient samples that had CD38 expression levels at or below the median as having low expression. There was a significant association between low expression of CD38 and lack of ZAP-70 or expression of a mutated IgVH (p &lt; 0.0001 for each assessment by the Fisher exact test). Median level of CD38 among cases expressing mutated IgVH was 4.0%, compared to 27.4% among cases expressing unmutated IgVH (p &lt; 0.0001 by the Wilcoxon rank sum test). Median level of CD38 among ZAP-70 negative cases was 5.3%, compared to 27.2% among ZAP-70+ cases (p &lt; 0.0001 by the Wilcoxon rank sum test). Patients with low-level expression of CD38 had a median time to initiation of therapy of 8.2 years; whereas, patients with high-level expression of CD38 had a median time to initiation of therapy of 4.0 years (p&lt;0.0001). Although high-level expression of CD38 was associated with a shorter time from diagnosis to initiation of therapy (p &lt; 0.0001 in a Cox proportional hazards regression), the inclusion of IgVH mutation status (p &lt; 0.0001) or expression of ZAP-70 (p &lt; 0.0001) in these models reduced the contribution of CD38 status to a p-value of 0.051 (ZAP-70 model) or 0.052 (mutation status model). Although ZAP-70 expression and mutation status each contributed significantly to the hazard of initiating therapy in a Cox proportional hazards model, high-level expression of CD38 did not add significantly to the model that already addresses ZAP-70 and mutational status, p=0.425. As such, although knowledge of the CD38 expression level can be used as a predictor of the time from diagnosis to the initiation of therapy it provides only marginal value if either the IgVH mutational status or expression of ZAP-70 is known and no value if knowledge of both ZAP-70 expression and IgVH mutational status is available.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 33-34
Author(s):  
Paula A. Lengerke Diaz ◽  
Michael Y. Choi ◽  
Eider F. Moreno Cortes ◽  
Jose V. Forero ◽  
Juliana Velez-Lujan ◽  
...  

Single oral targeted therapies have emerged as a standard of care in chronic lymphocytic leukemia (CLL). However, accessibility, side effects, and financial burden associated with long term administration limit their clinical use. Mainly, it is unclear in what clinical situation discontinuation of oral therapy can be recommended. The combination of type II anti-CD20 antibody obinutuzumab-Gazyva® with ibrutinib (GI) has shown a significant progression-free survival benefit in patients (pts) with CLL, including those with high-risk genomic aberrations. We conducted a phase 1b/2, single-arm, open-label trial to evaluate the safety and efficacy of GI as first-line treatment in 32 CLL pts. We report the outcome in pts that discontinued ibrutinib (either after 3 years of sustained complete response (CR) as stipulated in the clinical protocol, or due to other reasons). CLL pts enrolled in this protocol were ≥65 years old, or unfit/unwilling to receive chemotherapy. Pts received GI for six cycles, followed by daily single-agent ibrutinib. The protocol was designed to ensure that pts with a sustained CR after 36 months were allowed to discontinue ibrutinib. The median age was 66 years (IQR 59-73), and 6% of the evaluated pts had 17p deletion. All pts were able to complete the six planned cycles of obinutuzumab. The combination regimen was well-tolerated, and the most common adverse events (&gt;5% CTCAE grade 3-4) were neutropenia, thrombocytopenia, and hyperglycemia. The rate and severity of infusion-related reactions (IRR) were much lower than expected (Grade≥ 3, 3%), and pts without IRR had lower serum levels of cytokines/chemokines CCL3 (P=0.0460), IFN-γ (P=0.0457), and TNF-α (P=0.0032) after infusion. The overall response rate was 100%, with nine pts (28%) achieving a CR, and four pts (12.5%) with undetectable minimal residual disease (uMRD) in the bone marrow, defined as &lt;10-4 CLL cells on multicolor flow cytometry. At a median follow-up of 35.5 months (IQR 24.5-42.7) after starting treatment, 91% of the enrolled pts remain in remission with a 100% overall survival. Sixteen pts have completed a long-term follow-up of 36 months. Six pts showed CR, with three of them achieving uMRD in the bone marrow. Ten of these pts were in PR, and only one had disease progression and started treatment for symptomatic stage I disease with obinutuzumab plus venetoclax. In total, thirteen pts (41%) have stopped ibrutinib, with a median time on treatment prior to discontinuation of 35 months. Five (16%) of these pts had CRs and discontinued after 36 months. Eight additional pts (25%) had PRs and discontinued ibrutinib without being eligible: three pts discontinued prior to 36 months due to toxicities, and five pts discontinued after 36 months (3 due to side effects, and 2 due to financially driven decision). One patient eligible to discontinue ibrutinib, decided to remain on treatment despite sustained CR. After a median follow up time following ibrutinib discontinuation of 8 months (IQR 3.5-17), only two out of 13 pts have progressed (10 and 17 months after Ibrutinib discontinuation). None of the pts that stopped ibrutinib after achieving a CR have shown signs of disease progression. Of note, the pharmaceutical sponsor provided ibrutinib for the first 36 months, after which pts or their insurer became financially responsible. This particular scenario could bias the discontinuation pattern compared to a real world experience. It also provided us with a perspective about diverse factors affecting the treatment choices of pts. In summary, the obinutuzumab plus ibrutinib combination therapy was well-tolerated, with a much lower IRR rate. Efficacy compares favorably with historical controls with all pts responding to therapy, no deaths associated with treatment or disease progression, and a longer than expected time-to-progression after discontinuation of ibrutinib. The rate of ibrutinib discontinuation was higher than reported in the literature, most likely influenced by the protocol design and financial decisions driven by the switch from sponsor-provided ibrutinib to insurance or self-paid medication. Our observations regarding safety, efficacy and lack of disease progression after ibrutinib discontinuation are encouraging, and warrant confirmation in long-term prospective studies. Clinicaltrials.gov Identifier NCT02315768. Funding: Pharmacyclics LLC. Disclosures Choi: AbbVie: Consultancy, Speakers Bureau. Amaya-Chanaga:AbbVie: Ended employment in the past 24 months, Other: Research performed while employed as an investigator of this study at UCSD.. Kipps:Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Castro:Kite Pharma: Research Funding; Pharmacyclics: Research Funding; Fate Therapeutics: Research Funding.


Blood ◽  
2019 ◽  
Vol 133 (25) ◽  
pp. 2651-2663 ◽  
Author(s):  
Emanuela M. Ghia ◽  
Laura Z. Rassenti ◽  
Donna S. Neuberg ◽  
Alejandro Blanco ◽  
Fouad Yousif ◽  
...  

Abstract Targeted sequencing of 103 leukemia-associated genes in leukemia cells from 841 treatment-naive patients with chronic lymphocytic leukemia (CLL) identified 89 (11%) patients as having CLL cells with mutations in genes encoding proteins that putatively are involved in hedgehog (Hh) signaling. Consistent with this finding, there was a significant association between the presence of these mutations and the expression of GLI1 (χ2 test, P &lt; .0001), reflecting activation of the Hh pathway. However, we discovered that 38% of cases without identified mutations also were GLI1+. Patients with GLI1+ CLL cells had a shorter median treatment-free survival than patients with CLL cells lacking expression of GLI1 independent of IGHV mutation status. We found that GANT61, a small molecule that can inhibit GLI1, was highly cytotoxic for GLI1+ CLL cells relative to that of CLL cells without GLI1. Collectively, this study shows that a large proportion of patients have CLL cells with activated Hh signaling, which is associated with early disease progression and enhanced sensitivity to inhibition of GLI1.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 476-476
Author(s):  
Emanuela M. Ghia ◽  
Laura Z. Rassenti ◽  
Michael Y. Choi ◽  
Elvin Chu ◽  
George F. Widhopf II ◽  
...  

Venetoclax (Ven) is an inhibitor of BCL2 that is highly active in patients (pts) with chronic lymphocytic leukemia (CLL), effecting remissions without detectable minimal residual disease (MRD), particularly when used in combination with an anti-CD20 mAb (Seymour et al., N Engl J Med, 2018). However, pts can have persistent detectable MRD (i.e. ≥10-4 CLL cells by flow cytometry) after ≥1 year (yr) of Ven therapy (V-Rx); such pts are at risk for developing progressive disease (PD) even with continued V-Rx (Kater et al., J Clin Oncol, 2019). Evaluation of CLL cells from such pts may define biologic markers for pts who are likely to have persistent MRD after 1 yr of V-Rx and elucidate potential mechanism(s) of Ven resistance. We examined the CLL cells of pts (N=13) who had persistent MRD after ≥1 yr of V-Rx; 8 developed PD after a median time of 2 yrs on V-Rx and were designated as being in subgroup A1. Pts who had persistent MRD without PD after ≥1 yr of V-Rx were designated as being in subgroup A2 (N=5). For comparison we examined the pre-treatment (pre-Rx) CLL cells of pts who cleared MRD within 1 yr of therapy (N=5), and designated such pts as being in group B. The CLL cells of most pts expressed unmutated IGHV (i.e. 7/8 pts in A1, 3/5 pts in A2, and 5/5 pts in B). However, a high proportion of the pts with MRD after ≥1 yr of V-Rx had pre-Rx CLL cells with a complex karyotype and del17p (i.e. 5/8 pts in A1 and 2/5 pts in A2); whereas none of pre-Rx CLL cells of group B had a complex karyotype or del17p. We examined CLL cells for intracellular BCL2 and surface ROR1, which prior studies showed were correlative in CLL (Rassenti et al., Proc Natl Acad Sci U S A, 2017). The pre-Rx CLL cells of pts from subgroups A1 and A2 expressed significantly higher levels of ROR1 and BCL2 than the pre-Rx CLL cells of group B (P=0.03 and 0.0002, respectively, Mann-Whitney test). Furthermore, the CLL cells of pts with PD on V-Rx expressed significantly higher levels of ROR1 and BCL2 than the already high-levels expressed by the pre-Rx CLL cells of these same pts (P=0.002 and 0.01, respectively, Paired t test). We did not observe temporal changes in ROR1 or BCL2 in serial CLL samples collected over a comparable time interval from a comparator group of pts with adverse cytogenetics who did not receive V-Rx. We performed RNA sequencing with a mean of 70-million reads per sample on negatively-selected pre-Rx CLL cells from each pt, and on the isolated CLL cells from each of 6 pts in subgroup A1 when they had PD on V-Rx. Transcriptome analyses revealed the cancer-stemness gene-expression signature influenced by ROR1-signaling and associated with poorly-differentiated cancers (Choi et al., Cell Stem Cell, 2018; Malta et al., Cell, 2018) was significantly enriched in pre-Rx CLL of pts in subgroups A1 and/or A2 compared to group B (A1 and/or A2 vs. B had FDR q values of &lt;0.001). We also found the transcriptomes of CLL cells from pts with PD on V-Rx had a significantly greater enrichment in the cancer-stemness gene-expression signature than that of the pre-Rx CLL cells of the same pts (FDR q value &lt;0.001)! We identified the BCL2G101V mutation found earlier (Blombery et al., Cancer Discov, 2019) in the CLL cells of 3 of 6 pts with PD in subgroup A1 at allelic frequencies of less than 20%; this BCL2G101V mutation was not detected in pre-Rx CLL samples. We identified a new nonsynonymous BCL2 mutation at an allelic frequency of 49.3% in the CLL cells of 1 pt with PD who lacked the BCL2G101V mutation; this pt's pre-Rx CLL cells did not harbor detectable levels of this BCL2 mutation, which we deduce alters the BCL2 BH3-binding pocket. In summary, this study reveals that pts with CLL cells having complex cytogenetics, del17p, high-level expression of ROR1 and BCL2, and/or transcriptomes enriched for cancer-stemness may be at greater risk for having persistent MRD at ≥1 yr of V-Rx. Furthermore, the CLL cells of pts who develop PD on V-Rx have significantly higher levels of ROR1 and BCL2, BCL2 mutations, and transcriptomes with greater enrichment of the cancer-stemness signature than that of CLL cells from the same pts prior to V-Rx, implying that CLL cells resistant to Ven have greater cancer-cell de-differentiation. Because of the high frequency of mutations in BCL2 for pts with PD on V-Rx, strategies targeting ROR1 (Choi et al., Cell Stem Cell, 2018), rather than higher doses of Ven, may be more effective in mitigating the risk of PD in high-risk pts treated with Ven-based regimens. Disclosures Choi: Oncternal: Research Funding; Gilead: Consultancy, Speakers Bureau; Genentech: Consultancy, Speakers Bureau; Pharmacyclics: Consultancy, Research Funding, Speakers Bureau; Rigel: Consultancy, Research Funding; Abbvie: Consultancy, Research Funding, Speakers Bureau. Kipps:Pharmacyclics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Genentech, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Velos-Bio: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; Jannsen Pharmaceutical Companies of Johnson & Johnson: Honoraria, Membership on an entity's Board of Directors or advisory committees; AstraZeneca, Inc.: Membership on an entity's Board of Directors or advisory committees; Verastem: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3596-3596
Author(s):  
Claudia Haferlach ◽  
Frank Dicker ◽  
Susanne Schnittger ◽  
Wolfgang Kern ◽  
Torsten Haferlach

Abstract Abstract 3596 Introduction: Chronic lymphocytic leukemia (CLL) is a heterogeneous disease with a variable clinical course and a large spectrum of treatment options. Based on FISH data, a prognostic classification system has been established with 13q deletions as sole abnormality associated with a favorable prognosis and 17p and 11q deletions correlating with an unfavorable outcome. Recently, the combined evaluation of FISH data, IGHV mutation status and chromosome banding analysis (CBA) revealed that the impact of distinct genetic parameters differs with respect to overall survival (OS) and time to treatment (TTT). Thus far only few data is available on less frequent genetic abnormalities such as 14q deletions and translocations involving the IGH@ locus (tIGH). Therefore, we analyzed CLL with tIGH in detail with respect to frequency, partner genes and impact on prognosis. Methods/Patients: 78 CLL cases with tIGH were identified from 2,135 CLL sent to our laboratory for diagnostic work-up. All cases had been evaluated by immunphentotyping, FISH and CBA. Result: The most frequent tIGH was t(14;19)(q32;q13) (BCL3, n=21) followed by t(14;18)(q32;q21) (BCL2, n=19), t(8;14)(q24;q32) (CMYC, n=7) and t(11;14)(q13;q32) (CCND1, n=6). In the remaining 25 cases 5 recurrent translocations (t(2;14)(p13;q32), n=3; t(4;14)(p16;q32), FGFR3, n=2; t(11;14)(p15;q32), n=2; t(14;17)(q32;q25), n=2; and t(7;14)(q21;q32), n=2) were observed while the remaining 14 translocations were identified in single cases only. In 9/78 cases (11.5%) the tIGH was the sole abnormality. Recurrent additional chromosome abnormalities were +12 (n=7), del(13q) (n=9), del(11q) (n=3). A 17p deletion was observed in 1 case. In two cases tIGH was present only in a subclone and was a secondary abnormality occurring in addition to an del(11q) and a +12, respectively. CLL with tIGH were compared to 401 CLL without tIGH comprising all other genetic subgroups (subdivided according to Döhner et al.: del(17p) n=26, del(11q) n=42, +12 n=42, “normal” n=88, del(13q) sole n=177 and del(14q) n=26). An unmutated IGHV status was more frequent in CLL with tIGH as compared to all others (26/46 (54.3%) vs 128/353 (36.3%); p=0.023). For 53 cases with tIGH and all cases of the non-tIGH cohort clinical follow-up data was available. Median OS was 143.8 months (mo) in CLL with tIGH and 72.9 mo in patients with del(17p) while it was not reached in all other subgroups. In Cox regression analysis only del(17p) and mutated IGHV status were significantly associated with OS (p<0.0001, relative risk (RR)=7.0; p=0.014, RR=0.38). Median TTT was as follows: total cohort: 60.9 mo; tIGH: 27.8 mo; del(17p): 58.9 mo; del(11q): 19.7 mo; +12: n.r.; “normal” 63.9 mo; del(13q) sole: 83.0 mo and del(14q): 21.0 mo. In univariate Cox regression analysis the following parameters were significantly associated with shorter TTT: tIGH (p=0.004, RR=1.82), del(11q) (p<0.0001, RR=2.55), and del(14q) (p=0.007, RR=2.1), while del(13q) sole and mutated IGHV status were associated with longer TTT (p<0.0001, RR=0.40; p<0.0001, RR=0.23). In multivariate analysis including tIGH, del(11q), del(14q) and del(13q) sole all parameters retained their impact on TTT. However, if IGHV mutation status was included in the model only the mutated IGHV mutation status retained an impact on TTT (p<0.0001, RR=0.26). Next, patients with tIGH were subdivided according to their partner genes. Median OS was not reached in all subgroups, while median TTT was as follows: t(11;14): 101.2 mo, t(14;18): 47.9 mo, t(14;19): 11.0 mo, t(8;14): 18.5 mo and other partner genes: 27.8 mo. In univariate Cox regression analysis only t(14;19) was significantly associated with shorter TTT (p<0.001, RR=3.1). Including t(14;19) into multivariate analysis revealed a significant impact of both mutated IGHV mutation status and t(14;19) on TTT (p<0.0001, RR=0.286; p=0.004, RR=3.60). Conclusion: Translocations involving the IGH@ locus occur at low frequency in CLL. They are associated with unmutated IGHV status and a shorter TTT. TTT is especially short in cases with t(14;19). The prognostic impact of t(14;19) is independent of IGHV mutation status. In contrast CLL with t(11;14) and t(14;18) are neither associated with shorter OS nor shorter TTT. This data supports the application of CBA in CLL in order to identify all clinically relevant chromosomal aberrations, including those not detected by routine FISH analysis. Disclosures: Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Dicker:MLL Munich Leukemia Laboratory: Employment. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2445-2445
Author(s):  
Annika Dufour ◽  
Stefan K Bohlander ◽  
Evelyn Zellmeier ◽  
Gudrun Mellert ◽  
Karsten Spiekermann ◽  
...  

Abstract Abstract 2445 Chronic lymphocytic leukemia (CLL) patients with a deletion of the TP53 tumor supressor gene located at 17p13 have a poor prognosis in first line chemotherapy regimens. Recent studies indicated somatic TP53 mutations as a prognostic factor in CLL independent of 17p13 deletion status. We aimed to further characterize the prognostic value and the impact of TP53 mutations on progression-free survival (PFS) in the presence and absence of a 17p13 deletion in previously treated and relapsed CLL patients within an international phase III clinical study comparing Fludarabine and Cyclophosphamide with or without Rituximab (FC versus R-FC: REACH trial). We analyzed 457 patients at diagnosis for mutations in the TP53 gene using a combination of a microarray-based resequencing assay (AmpliChip p53 Test, Roche Molecular Systems, USA.) and Sanger sequencing of TP53 exons 2–10. The data were correlated with clinical and biologic markers as well as with interphase fluorescence in situ hybridization (FISH) and with PFS. Association of the clinical data with PFS was assessed by Cox proportional hazard models. To estimate the functional significance of the individual TP53 mutations we used the IARC TP53 database. TP53 mutations (n=60) were detected in 52 of 457 patients (11.4%) and included 42 missense, 4 nonsense, 8 frameshift mutations, 2 in-frame deletions and 4 mutations in splice sites. Among other clinical variables, only 17p13 deletion was associated with TP53 mutations: 27 of 52 TP53 mutated patients had a 17p13 deletion (concordance rate: 52%, Fisher's test p<0.001). Median PFS for patients with TP53 mutations (n=52, 13 months, HR=1.9 (1.4–2.7), p<0.001) was significantly shorter as compared to patients without TP53 mutations (n=480, 27 months). In a sub-group analysis, chemoimmunotherapy including Rituximab did not significantly improve the PFS of patients with TP53 mutations. Multivariate analysis including treatment arm, Binet stage, age, IGVH mutational status, 17p13 deletion and TP53 mutation status confirmed TP53 mutation status (HR-TP53=1.7 (1.1–2.6), p=0.009) as a prognostic factor for PFS independent of 17p13 deletion status (HR-17p=1.7 (1.1–2.7), p=0.024) and with a similar effect size. The other independent prognostic factors were treatment (HR=0.61 (0.48–0.76), p<0.001), Binet stage (HR=1.64 (1.3–2.1), p<0.001) and IGVH mutational status (HR=2.4 (1.85–3.1), p<0.001). To further dissect the contribution of TP53 mutation and 17p13 deletion on PFS, we considered a multivariate analysis comparing patients with both TP53 mutation and 17p13 deletion (n=28), with only 17p13 deletion (n=9), with a dominant negative TP53 mutation or multiple TP53 mutations (n=8) or with a single TP53 mutation (n=16) against patients without TP53 abnormalities (n=271), adjusted for treatment, Binet stage, age and IGVH mutational status. Patients with a predicted biallelic disruption of TP53 either by a TP53 mutation in combination with a 17p13 deletion (HR: 2.8 (1.8,4.2), p=<0.001) or patients with a dominant negative TP53 mutation as predicted by the IARC TP53 database or multiple TP53 mutations (HR=3.26 (1.5,7.1), p=0.003) had a risk similar in size and which was quite high for disease progression (the reference to calculate the risk, here and in the following, is always the group of patients without TP53 abnormalities). The risk slightly decreased for patients with only a deletion 17p13 (HR=2.2, (1.1–4.3), p=0.021). Very interestingly, single TP53 mutations showed a much lower risk for disease progression (in this case not even significant) (HR=1.61 (0.9–2.8), p=0.084) especially compared to the risk conferred by a biallelic disruption. In this large cohort of previously treated CLL patients, complete disruption of TP53 function (by a combination of a 17p13 deletion and a TP53 mutation, through dominant negative TP53 mutations or through multiple TP53 mutations) was associated with a higher risk for disease progression. Prognosis of patients with a single TP53 mutation was not significantly different from patients without TP53 aberrations. It remains to be shown whether CLL patients with a single TP53 mutation are at a higher risk of acquiring additional mutations of TP53 during disease progression. Prognostic stratification of previously treated CLL patients should include a routine molecular TP53 mutational analysis in addition to deletion analysis of the TP53 locus by FISH. Disclosures: Dufour: Roche: Research Funding. Bohlander:Roche: Research Funding. Spiekermann:Roche: Research Funding. Schneider:Roche: Research Funding. Hiddemann:Roche: Research Funding. Truong:Roche: Employment. Patten:Roche: Employment. Wu:Roche: Employment. Dmoszynska:Mundipharma:; Roche: Honoraria. Robak:Centocor Ortho Biotech Research & Development: Research Funding. Geisler:Roche: Speakers Bureau. Dornan:Genentech: Employment. Lin:Genentech: Employment. Yeh:Genentech: Employment. Weisser:Roche: Employment. Duchateau-Nguyen:Roche: Employment. Palermo:Roche: Employment.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3891-3891
Author(s):  
Laura Z. Rassenti ◽  
Emanuela M. Ghia ◽  
Lillian Werner ◽  
Donna Neuberg ◽  
George F. Widhopf ◽  
...  

Abstract Abstract 3891 The leukemia B cells of patients (pts) with chronic lymphocytic leukemia (CLL) express a restricted repertoire of immunoglobulin heavy chain variable region (IGHV) genes. Moreover, certain IGHV genes appear over-represented in this repertoire. Among these, IGHV1-69 was first identified as most frequently expressed, being used by the CLL cells of nearly 20% of all pts (PNAS, 86:5913–7, 1989). CLL cells most frequently express IGHV1-69 without somatic mutations and often with restricted D and JH segment use, providing for stereotypic motifs in the heavy chain third complementarity determining region (HCDR3). We addressed whether there were peculiar biologic or clinical features of pts with CLL that used IGHV1-69. For this, we studied 452 pts identified in a cohort of 2,866 followed by the CLL Research Consortium (CRC) found to have CLL cells that express IGHV1-69. This accounted for 16% of all pts. We found that 420 of 452 CLL samples (93%) express IGHV1-69 without somatic mutation (≥98% sequence homology with germline IGHV1-69), which is in significant contrast to the frequency use of UM IGHV among CLL samples that do not use IGHV1-69. As noted for CLL pts in general, there is a strong association between mutation status and clinical behavior. Among pts that use IGHV1-69, the 32 of 452 pts that use MU IGHV1-69 had a highly indolent clinical course, with a median time from diagnosis to initial treatment (TFS) of 17.3 years. This was significantly longer than the median TFS of 2.8 yrs for the 452 pts that used UM IGHV1-69 (p<0.0001). Among the pts that used UM IGHV1-69 we identified a stereotypic HDCR3 motif shared by more than one patient in 249/452 (55%) of the cases. Multivariate analysis failed to discriminate any significant differences in the median TFS of pts that used IGHV1-69 that had a stereotypic CDR3 motif versus pts who had an idiosyncratic HCDR3 (2.9 yrs vs 3.0 yrs, respectively p=0.14). Interphase FISH for common cytogenetic aberrations in CLL were available for 281 of the 452 cases. Among these, 58% of the cases had deletions at 17p (18%), 11q (23%), or trisomy 12 (17%). The remaining cases had no detectable chromosomal abnormalities (24%) or isolated deletion of 13q (18%). The CLL cells of all 452 pts were examined for ZAP-70. There was a strong association between the expression of ZAP-70 and use of UM IGHV1-69. However, the association between ZAP-70 expression and use of UM IGHV1-69 was not absolute. Only 70% with UM IGHV1-69 were ZAP-70 positive, as were 12.5% that used M IGHV1-69. Of all 452 pts that expressed IGHV1-69, 300 (66%) had ZAP-70 positive CLL cells. These pts had a median TFS of 2.3 yrs, which was significantly shorter than that of the remaining 152 pts with ZAP-70-negative CLL, who had a median TFS of 4.3 yrs (p<0.0001). Moreover, of the 420 pts that used UM IGHV1-69, 296 (70%) had CLL cells that expressed ZAP-70; these pts had a median TFS of 2.3 yrs. This was significantly shorter than the median TFS of pts with CLL cells that express UM IGHV1-69, but were ZAP-70 negative 4.1 yrs (p<0.0001). A Cox regression model revealed that although the presence of detectable chromosomal aberrations was associated to a shorter median TFS, ZAP-70 was a stronger predictor of short TFS (HR for 13q =1.1 p =0.03, HR for trisomy 12 =1.2 p =0.03, HR for 11q =1.6 p =0.03, HR for 17p =1.8, p =0.03) (HR for ZAP-70 positive = 1.8, p=0.0004). The Cox regression model was used to assess the associations of ZAP-70, and the use or not of the UM IGHV1-69 gene with TFS (p-value <0.05 were considered as significant). We investigated these associations using a previously published cohort of characterized 705 CLL pts (Blood.2008;112:1923). The HR associated with the expression of ZAP-70 (HR=3.2) (p<0.0001) was significantly higher than if either the UM IGHV1-69 or the cases with UM IGHV other than IGHV1-69 were incorporated into the model (HR=1.9 and HR=1.6 respectively, p=0.001). We conclude that cases that use IGHV1-69 are peculiar in that they more frequently use UM IGHV and appear to have a higher frequency of adverse cytogenetic features than CLL cases at large. In addition, we found that CLL-cell expression of ZAP-70 can segregate pts that use UM IGHV1-69 into subgroups with disparate clinical behavior, despite the fact that all patients use the same IGHV gene. Moreover, multivariable analyses revealed that ZAP-70 was strongest predictor of short TFS among all other considered prognostic parameters in this distinctive cohort of pts. Disclosures: Kipps: Igenica: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Research Funding; Abbott Industries: Research Funding; Genentech: Research Funding; GSK: Research Funding; Gilead Sciences: Consultancy, Research Funding; Amgen: Research Funding.


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