scholarly journals Resistance to BTK inhibition by ibrutinib can be overcome by preventing FOXO3a nuclear export and PI3K/AKT activation in B-cell lymphoid malignancies

2019 ◽  
Vol 10 (12) ◽  
Author(s):  
Isha Kapoor ◽  
Yue Li ◽  
Arishya Sharma ◽  
Huayuan Zhu ◽  
Juraj Bodo ◽  
...  
Keyword(s):  
B Cell ◽  
Cell Lines ◽  
Nuclear Export ◽  
Acquired Resistance ◽  
B Cell Lymphoma ◽  
Lymphocytic Leukemia ◽  
Nuclear Accumulation ◽  
Lymphoid Malignancies ◽  
Ibrutinib Resistance ◽  
Induced Apoptosis

AbstractChronic activation of the Bruton’s tyrosine kinase (BTK)-mediated B-cell receptor (BCR) signaling is a hallmark of many B-cell lymphoid malignancies, including chronic lymphocytic leukemia (CLL) and diffuse large B-cell lymphoma (DLBCL). Ibrutinib, an FDA approved, orally administered BTK inhibitor, has demonstrated high response rates, however, complete responses are infrequent and acquired resistance to BTK inhibition can emerge. In this study, we generated ibrutinib-resistant (IB-R) cell lines by chronic exposure of CLL and activated B-cell (ABC)-DLBCL cells to ibrutinib in order to investigate the mechanism of acquired resistance to ibrutinib. IB-R cell lines demonstrated downregulation of FOXO3a and PTEN levels and activation of AKT, with their levels being low in the nuclei of resistant cells in comparison to the sensitive counterparts. Inhibition of PI3K and AKT using idelalisib and MK2206, respectively increased ibrutinib-induced apoptosis in IB-R cells by downregulation of pAKT473 and restoring FOXO3a levels, demonstrating the importance of these cell survival factors for ibrutinib-resistance. Notably, the exportin 1 inhibitor, selinexor synergized with ibrutinib in IB-R cells and restored nuclear abundance of FOXO3a and PTEN, suggesting that nuclear accumulation of FOXO3a and PTEN facilitates increase in ibrutinib-induced apoptosis in IB-R cells. These data demonstrate that reactivation of FOXO3a nuclear function enhances the efficacy of ibrutinib and overcomes acquired resistance to ibrutinib. Together, these findings reveal a novel mechanism that confers ibrutinib resistance via aberrant nuclear/cytoplasmic subcellular localization of FOXO3a and could be exploited by rational therapeutic combination regimens for effectively treating lymphoid malignancies.

Mediation of apoptosis by and antitumor activity of lumiliximab in chronic lymphocytic leukemia cells and CD23+ lymphoma cell lines

Blood ◽  
2008 ◽  
Vol 111 (3) ◽  
pp. 1594-1602 ◽  
Author(s):  
Nuzhat I. Pathan ◽  
Peter Chu ◽  
Kandasamy Hariharan ◽  
Carolyn Cheney ◽  
Arturo Molina ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Antitumor Activity ◽  
B Cell ◽  
Cell Lines ◽  
Human Monoclonal Antibody ◽  
B Cell Lymphoma ◽  
Lymphocytic Leukemia ◽  
Synergistic Cytotoxicity ◽  
Induced Apoptosis

AbstractLumiliximab is a chimeric macaque-human monoclonal antibody to CD23, a protein expressed on virtually all chronic lymphocytic leukemia (CLL) cells. We examined the ability of lumiliximab to mediate apoptosis, antibody-dependent cellular cytotoxicity, and complement-dependent cytotoxicity against primary CLL cells and CD23-expressing B-cell lines. Our data suggest that lumiliximab kills CLL cells and CD23-expressing B cells predominantly by apoptosis, which occurs through the intrinsic pathway. Lumiliximab-induced apoptosis was accompanied by the down-regulation of antiapoptotic proteins Bcl-2, Bcl-XL, and XIAP, activation of Bax, and release of cytochrome c from the mitochondria. We also found that the addition of lumiliximab to rituximab or fludarabine results in synergistic cytotoxicity of primary CLL cells and CD23-expressing B-cell lines. We investigated the in vivo activity of lumiliximab in a human disseminated CD23+ B-cell lymphoma SCID mouse model and found greater antitumor activity with it than with control antibody. We also found that paralysis-free survival was greater with lumiliximab plus rituximab or fludarabine than with any of those agents alone. These results suggest that lumiliximab may be an effective treatment alone or in combination with rituximab or chemotherapy agents in CLL or other CD23-overexpressing B-cell malignancies.

scholarly journals The biology behind B-cell lymphoma 2 as a target in chronic lymphocytic leukemia

2016 ◽  
Vol 7 (6) ◽  
pp. 321-329 ◽  
Author(s):  
Valentín Ortíz-Maldonado ◽  
Pablo Mozas ◽  
Julio Delgado
Keyword(s):  
Clinical Trials ◽  
Chronic Lymphocytic Leukemia ◽  
B Cell ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Mitochondrial Pathway ◽  
Therapeutic Agents ◽  
Lymphocytic Leukemia ◽  
Hallmarks Of Cancer ◽  
Lymphoid Malignancies

B-cell lymphoma 2 (BCL2)-type proteins are key regulators of the intrinsic or mitochondrial pathway for apoptosis. Since escape from apoptosis is one the main ‘hallmarks of cancer’, BCL2 inhibitors have emerged as promising therapeutic agents for diverse lymphoid malignancies, particularly chronic lymphocytic leukemia (CLL). Multiple clinical trials have shown efficacy of these agents in patients with relapsed/refractory disease with a favorable toxicity profile. Moreover, some clinical trials indicate that combination with monoclonal antibodies and other novel agents may enhance their effect.

CD40L Modulates TRAIL-Induced Apoptosis in Germinal Center Derived B Cell Lymphomas.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 4630-4630
Author(s):  
Marion Travert ◽  
Patricia Ame-Thomas ◽  
Thierry Fest ◽  
Céline Pangault ◽  
Gilbert Semana ◽  
...  
Keyword(s):  
Follicular Lymphoma ◽  
B Cell ◽  
Cell Lines ◽  
Germinal Center ◽  
B Cell Lymphoma ◽  
B Cell Lymphomas ◽  
Lymphoma Cells ◽  
Over Expression ◽  
Induced Apoptosis ◽  
Transformed Cell Lines

Abstract Follicular lymphoma are characterized by the rearrangement of the bcl-2 gene, present in more than 90% of patients. Over-expression of the bcl-2 protein resulting from this translocation is associated with the inability to eradicate the lymphoma, by inhibiting apoptosis. Despite the median survival ranges from 8 to 15 years, leading to the designation of indolent lymphoma, patients with advanced-stage follicular lymphoma are not cured with current therapeutic options. Numerous reports have shown that Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) can induce apoptosis in a wide variety of transformed cell lines of diverse lineage, but does not appear to kill normal cells, even though TRAIL mRNA is expressed at significant levels in most normal tissues. As cell death induced by TRAIL occurs almost exclusively in tumor cells, it suggests that this drug is safe to use as an antitumor therapy. We therefore investigated the efficiency of this cytokine to induce apoptosis in germinal center derived B cell lymphoma, despite bcl-2 over-expression. Our study was also designed to evaluate the role of CD40L, one of the main differentiation signal involved in B cell maturation during the germinal center reaction, on the regulation of TRAIL-induced apoptosis. This study was performed on three germinal center derived tumor cell lines (BL2, VAL and RL), and on normal and tumor primary cells obtained from human tonsils and lymph nodes. Our data show that normal B lymphocytes obtained from tonsil biopsies are resistant to TRAIL-mediated apoptosis, when B lymphoma cells issued from lymph node of numerous patients are significantly sensitive to the cytokine. When we treat these lymphoma cells with trimeric huCD40L, we partly rescue these cells from spontaneous apoptosis which naturally occurs after few days of culture, and reverse by 50% TRAIL-mediated apoptosis when cells were co-treated with huCD40L for 16 hours. Similar results were reproduced on some germinal center derived cell lines. BL2 was indeed found highly sensitive to TRAIL-induced apoptosis following a 24 hour exposure. On the opposite, VAL and RL were almost insensitive. We have demonstrate that apoptosis is exclusively mediated by TRAIL-R1 in BL2. Analysis of signalling pathways revealed that the protection to TRAIL-induced apoptosis by CD40L is due to some specific anti-apoptotic molecules that will be described. Genes encoding these molecules are targets of the NFκB signalling pathway activated by CD40L. Our results suggest that activation of NFκB and induction of anti-apoptotic molecules by CD40L play an important role in the protection of germinal center derived B cell lymphomas against apoptosis. Then, NFκB inhibitors may be wise to use in clinical trials in conjunction with TRAIL against follicular lymphomas.

Phospho-SFKs (Y416) As a Potential Predictive Marker for Dasatinib Therapy in B-Cell Non-Hodgkin Lymphoma and Chronic Lymphocytic Leukemia,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3727-3727
Author(s):  
Xiaoxian Zhao ◽  
Eric D. Hsi
Keyword(s):  
B Cell ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Predictive Marker ◽  
Lymphocytic Leukemia ◽  
Lymphoma Cell ◽  
Raji Cells ◽  
B Lymphoma ◽  
Induced Apoptosis

Abstract Abstract 3727 The Src family of protein tyrosine kinases (SFKs) plays an important role in regulating multiple signaling networks including B-cell receptors (BCR) mediated pathways and abnormal SFK kinase activation promotes B lymphoma cell survival. Dasatinib is an oral BCR/ABL1 and SKF inhibitor useful in the treatment of imatinib-resistant CML and Ph+ALL. Given its broad inhibitory activity, dasatinib may be useful in the treatment of other hematologic malignancies and having a biologic predictor of response would be helpful in rational selection of this targeted therapeutic. We hypothesized this agent could have therapeutic potential against lymphoma patients with p-SFK (Y416) expression. Constitutive p-SFK (Y416) expression (indicating active SFK signaling) was detected in both B-lymphoma cell lines and a subset of primary lymphoma tissues including diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), mantle cell lymphoma (MCL), Burkitt lymphoma and small lymphocytic leukemia (SLL). Dasatinib induced apoptosis of B-lymphoma Raji cells correlated with high level expression of constitutive p-SFK (Y416) and dasatinib rapidly reduced the global level of tyrosine phosphorylations including p-SFK (Y416) in Raji cells. 19 of 28 lymphoma cases (67.9%) were positive for p-SFK (Y416) by Western blot analysis. Dasatinib displayed in vitro dose-dependent (10–200 nM) killing activity against 17 of those 19 p-SFK (Y416) cases (89.5%). In contrast, only 2 of 9 p-SFK (Y416) negative cases (22.2%) had response to dasatinib exposure. Thus presence of p-SFK (Y416) was associated with in vitro response to dasatinib (p <0.0001). Similar to tested Raji cells, dasatinib induced apoptosis of primary B-cell lymphoma cells was accompanied with de-phosphorylation of p-SFK (Y416) and cleavage of caspase-3. 6 of 9 tested CLL cases were p-SFK (Y416) positive. Dasatinib displayed in vitro killing activities against 5 of 6 positive cases with a range of killing from 12% to 53% (mean 26.5%) of malignant B-cells. Meanwhile, one of three negative cases showed response to dasatinib (17% killing). We conclude that p-SFK (Y416) may be a useful predictive marker of response to dasatinib. Potential uses include pharmacodynamic monitoring or integral biomarker for selecting appropriate patients with B-cell malignancies for clinical trials. Disclosures: No relevant conflicts of interest to declare.

Genome Wide Studies in Multiple Myeloma Identify XPO1/CRM-1 As a Critical Target Validated Using the Selective Inhibitor of Nuclear Export (SINE) KPT-276

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 573-573
Author(s):  
Jessica Schmidt ◽  
Esteban Braggio ◽  
Marta Chesi ◽  
Jan Egan ◽  
Yuan Xiao Zhu ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
B Cell ◽  
Cell Lines ◽  
Nuclear Export ◽  
Research Funding ◽  
Phase 1 ◽  
A549 Cells ◽  
B Cell Lymphoma ◽  
Anticancer Activities

Abstract Abstract 573 Using high throughput RNA interference screening on 6,722 druggable genes we previously identified XPO1/CRM1 as one of the 50 most vulnerable targets in Multiple Myeloma (MM)1. XPO1 knockdown proved lethal in MM cell lines, but had no effect on human embryonic kidney (293) cells or lung cancer (A549) cells, showing that XPO1 is a specific myeloma vulnerability, and that myeloma cell survival is dependent upon XPO1 expression. XPO1 encodes the protein exportin 1, a nuclear transport protein that exports tumor suppressor proteins from the nucleus, where they are active, to the cytoplasm, where they become inactive. We next analyzed XPO1 in MM via gene expression profiling (GEP). XPO1 expression is up-regulated as the disease progresses: patients with active MM have a higher level of XPO1 compared to normal plasma cells (p<0.04) and to patients with monoclonal gammopathy of undetermined significance or smoldering MM (p<0.0001). The highest levels were in human MM cell lines. TC classification revealed highest levels in t(11;14) and lowest levels in t(4;14) disease. Selective inhibitors of nuclear export (SINE) compounds have recently been developed that irreversibly inhibit XPO1/CRM1 and its nuclear export function. One such inhibitor, KPT-276, decreased the viability of all 12 MM cell lines tested in vitro, as shown by MTT assay. After 72 hours of drug treatment, a median IC50 value of approximately 175 nM (range 30–1000 nM) was observed. No synergy with other commonly used anti-MM therapeutics was observed in vitro. In contrast, the drug had little effect in 8 solid tumor cell lines with the exception of the B cell lymphoma line Ramos. KPT-276 was also consistently active in inducing apoptosis against MM primary patient samples. Using an IC80 dose of KPT-276, drug-treated samples had a reduced population of cells in S phase (8%) compared to cells treated with DMSO (21%). Using the vkappa*myc transgenic MM model, KPT-276 reduced monoclonal spikes (by a mean of 56%) in all mice treated orally with 150 mg/kg dose three times per week for 4 weeks. Furthermore, KPT-276 significantly reduced tumor growth in a xenograft MM1.S mouse model. GEP was performed in the presence or absence of drug in two different MM cell lines. Two genes of probable relevance, cell division cycle 25 homolog A (CDC25A) and Bromodomain-containing protein 4 (BRD4), were dysregulated by SINE treatment. Both are involved in cell cycle control and have been linked to MYC. RT-PCR and western blotting confirm that MYC, CDC25A and BRD4 are down-regulated, as soon as six hours, after treatment with KPT-276. KPT-276 has shown marked anticancer activities against B cell malignancies in vitro and is active and tolerated in Phase I canine studies. KPT-330, a close analog of KPT-276, is currently in Phase 1 studies in human with advanced hematological and solid tumors. Disclosures: Schmidt: Karyopharm: Research Funding. McCauley:Karyopharm Therapeutics Inc: Employment. Shacham:Karyopharm Therapeutics: Employment. Kauffman:Karyopharm Therapeutics Inc: Employment. Stewart:Millenium: Consultancy, Honoraria, Research Funding; Onyx: Consultancy; Celgene: Consultancy.

Recurrent Mutations of the Exportin 1 Gene (XPO1) in Primary Mediastinal B-Cell Lymphoma: A Lysa Study

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 129-129 ◽  
Author(s):  
Fabrice Jardin ◽  
Anais Pujals ◽  
Laura Pelletier ◽  
Elodie Bohers ◽  
Vincent Camus ◽  
...  
Keyword(s):  
Gene Expression ◽  
B Cell ◽  
Cell Lines ◽  
Nuclear Export ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
Wild Type ◽  
U2os Cells ◽  
Aggressive B Cell Lymphoma

Abstract Background and aim of the study Primary mediastinal B-cell lymphoma (PMBL) is an entity of aggressive B-cell lymphoma that is clinically and biologically distinct from the other molecular subtypes of diffuse large B-cell lymphoma (DLBCL). We recently detected by Whole exome sequencing a recurrent point mutation in the XPO1 (exportin 1) gene (also referred to as chromosome region maintenance 1; CRM1), which resulted in the Glu571Lys (p.E571K) missense substitution in 2 refractory/relapsed PMBL (Dubois et al., ICML 2015; Mareschal et al. AACR 2015). XPO1 is a member of the Karyopherin-b superfamily of nuclear transport proteins. XPO1 mediates the nuclear export of numerous RNAs and cellular regulatory proteins, including tumor suppressor proteins. This mutation is in the hydrophobic groove of XPO1 that binds to the leucine-rich nuclear export signal (NES) of cargo proteins. In this study, we investigated the prevalence, specificity, and biological / clinical relevance of XPO1 mutations in PMBL. Patients and methods High-throughput targeted or Sanger sequencing of 117 PMBL patients and 3 PMBL cell lines were performed. PMBL cases were defined either molecularly by gene expression profile (mPMBL cohort) or by standard histological method (hPMBL cohort) and enrolled in various LYSA (LYmphoma Study Association) clinical trials. To assess the frequency and specificity of XPO1 mutations, cases of classical Hodgkin lymphoma (cHL) and primary mediastinal grey zone lymphoma (MGZL) were analysed. Cell experiments were performed to assess the impact of the E571 mutation on the activity of selective inhibitor of nuclear export (SINE) molecules. Results XPO1 mutations were present in 28/117 (24%) PMBL cases but were rare in cHL cases (1/19, 5%) and absent from MGZL cases (0/20). A higher prevalence (50%) of the recurrent codon 571 variant (p.E571K) was observed in PMBL cases defined by gene expression profiling (n = 32), as compared to hPMBL cases (n = 85, 13%). No difference in age, International Prognostic Index (IPI) or bulky mass was observed between the PMBL patients harboring mutant and wild-type XPO1 in the overall cohort whereas a female predominance was noticed in the mPMBL cohort. Based on a median follow-up duration of 42 months, XPO1 mutant patients exhibited significantly decreased PFS (3y PFS = 74% [CI95% 55-100]) compared to wild-type patients (3y PFS = 94% [CI95% 83-100], p=0.049) in the mPMBL cohort. In 4/4 tested cases, the E571K variant was also detected in cell-free circulating plasmatic DNA, suggesting that the mutation can be used as a biomarker at the time of diagnosis and during follow-up. Importantly, the E571K variant was detected as a heterozygous mutation in MedB-1, a PMBL-derived cell line, whereas the two other PMBL cell lines tested, Karpas1106 and U-2940, did not display any variants in XPO1 exon 15. KPT-185, the SINE compound that blocks XPO1-dependent nuclear export, induced a dose-dependent decrease in cell proliferation and increased cell death in the PMBL cell lines harbouring wild type or mutated alleles. To test directly if XPO1 mutation from E571 to E571K alters XPO1 inhibition by SINE compounds, the mutated protein was tested in vitro. The E571XPO1 mutated allele was transiently transfected into osteosarcoma U2OS cells which stably express the fluorescently labelled XPO1 cargo REV. Cells were treated with the clinical SINE compound selinexor, which is currently in phase I/II clinical trials and nuclear localization of REV-GFP was analysed in red transfected cells. The results showed that the nuclear export of the mutated XPO1 protein was inhibited by selinexor similarly to the wild-type XPO1 protein (Figure 1). Conclusion Although the oncogenic properties of XPO1 mutations remain to be determined, their recurrent selection in PMBL strongly supports their involvement in the pathogenesis of this curable aggressive B-cell lymphoma. XPO1 mutations were primarily observed in young female patients who displayed a typical PMBL molecular signature. The E571K XPO1 mutation represents a novel hallmark of PMBL but does not seem to interfere with SINE activity. Rev-GFP (green fluorescent) expressing U2OS cells were transfected with wild type XPO1-RFP (red fluorescent protein), XPO1-C528S-RFP, XPO1-E571K-mCherry, and XPO1-E571G-mCherry. The cells were then treated with 1µM KPT-330 for 8 hours. Figure 1. Rev-GFP expressing U2OS cells transfected with XPO1 variants. Figure 1. Rev-GFP expressing U2OS cells transfected with XPO1 variants. Disclosures Landesman: Karyopharm Therapeutics: Employment. Senapedis:Karyopharm Therapeutics, Inc.: Employment, Patents & Royalties. Argueta:Karyopharm Therapeutics: Employment. Milpied:Celgene: Honoraria, Research Funding.

scholarly journals Dual mTORC1/mTORC2 inhibition diminishes Akt activation and induces Puma-dependent apoptosis in lymphoid malignancies

Blood ◽  
2012 ◽  
Vol 119 (2) ◽  
pp. 476-487 ◽  
Author(s):  
Mamta Gupta ◽  
Andrea E. Wahner Hendrickson ◽  
Seong Seok Yun ◽  
Jing Jing Han ◽  
Paula A. Schneider ◽  
...  
Keyword(s):  
Mantle Cell Lymphoma ◽  
Cell Lines ◽  
Transcriptional Activation ◽  
Cell Lymphoma ◽  
Lymphocytic Leukemia ◽  
Clinical Samples ◽  
Lymphoid Malignancies ◽  
Mantle Cell ◽  
Induced Apoptosis

Abstract The mammalian target of rapamycin (mTOR) plays crucial roles in proliferative and antiapoptotic signaling in lymphoid malignancies. Rapamycin analogs, which are allosteric mTOR complex 1 (mTORC1) inhibitors, are active in mantle cell lymphoma and other lymphoid neoplasms, but responses are usually partial and short-lived. In the present study we compared the effects of rapamycin with the dual mTORC1/mTORC2 inhibitor OSI-027 in cell lines and clinical samples representing divers lymphoid malignancies. In contrast to rapamycin, OSI-027 markedly diminished proliferation and induced apoptosis in a variety of lymphoid cell lines and clinical samples, including specimens of B-cell acute lymphocytic leukemia (ALL), mantle cell lymphoma, marginal zone lymphoma and Sezary syndrome. Additional analysis demonstrated that OSI-027–induced apoptosis depended on transcriptional activation of the PUMA and BIM genes. Overexpression of Bcl-2, which neutralizes Puma and Bim, or loss of procaspase 9 diminished OSI-027–induced apoptosis in vitro. Moreover, OSI-027 inhibited phosphorylation of mTORC1 and mTORC2 substrates, up-regulated Puma, and induced regressions in Jeko xenografts. Collectively, these results not only identify a pathway that is critical for the cytotoxicity of dual mTORC1/mTORC2 inhibitors, but also suggest that simultaneously targeting mTORC1 and mTORC2 might be an effective anti-lymphoma strategy in vivo.

scholarly journals Dietary flavonoids inhibit the anticancer effects of the proteasome inhibitor bortezomib

Blood ◽  
2008 ◽  
Vol 112 (9) ◽  
pp. 3835-3846 ◽  
Author(s):  
Feng-Ting Liu ◽  
Samir G. Agrawal ◽  
Zanyar Movasaghi ◽  
Peter B. Wyatt ◽  
Ihtesham U. Rehman ◽  
...  
Keyword(s):  
Boric Acid ◽  
B Cell ◽  
Cell Lines ◽  
Proteasome Inhibitor ◽  
Inhibitory Effect ◽  
Lymphocytic Leukemia ◽  
Dependent Manner ◽  
Tumor Cell Death ◽  
Induced Apoptosis ◽  
Dietary Flavonoids

Abstract Dietary flavonoids have many health-promoting actions, including anticancer activity via proteasome inhibition. Bor-tezomib is a dipeptide boronate proteasome inhibitor that has activity in the treatment of multiple myeloma but is not effective in chronic lymphocytic leukemia (CLL). Although CLL cells are sensitive in vitro to bortezomib-induced apoptosis when cultured in medium, the killing activity was blocked when cultured in 50% fresh autologous plasma. Dietary flavonoids, quercetin and myricetin, which are abundant in plasma, inhibited bortezomib-induced apoptosis of primary CLL and malignant B-cell lines in a dose-dependent manner. This inhibitory effect was associated with chemical reactions between quercetin and the boronic acid group, -RB(OH)2, in bortezomib. The addition of boric acid diminished the inhibitory effect of both quercetin and plasma on bortezomib-induced apoptosis. The protective effect was also reduced when myeloma cell lines, but not B-cell lines, were preincubated with quercetin, indicating a direct effect of quercetin on myeloma cells. At high doses, quercetin itself induced tumor cell death. These data indicate that dietary flavonoids limit the efficacy of bortezomib, whereas supplemental inorganic boric acid is able to reverse this. The complex interactions between quercetin, tumor cells, and bortezomib mean caution is required when giving dietary advice to patients.

scholarly journals Identification of Anti-Lymphoma Biomarkers of Response to the Anti-CD37 Antibody Drug Conjugate (ADC) IMGN529

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4187-4187 ◽  
Author(s):  
Eugenio Gaudio ◽  
Chiara Tarantelli ◽  
Alberto Arribas ◽  
Luciano Cascione ◽  
Ivo Kwee ◽  
...  
Keyword(s):  
T Cell ◽  
B Cell ◽  
Cell Lines ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
T Cell Lymphoma ◽  
Lymphoma Cell ◽  
Cell Of Origin ◽  
Antibody Drug Conjugate ◽  
Induced Apoptosis

Abstract Background IMGN529 is an antibody drug conjugate (ADC) consisting of an anti-CD37 antibody with direct anti-tumor activity conjugated via a thioether linker to the cytotoxic maytansinoid antimicrotubule agent DM1. IMGN529 has shown pre-clinical (Deckert et al, Blood 2013) and clinical activity in lymphoma (Stathis et al, ASH 2014; NCT01534715). Here, we assessed the anti-tumor activity of IMGN529 on a large panel of B cell and T cell human lymphomas to identify potential biomarkers of response. Methods Fifty-four lymphoma cell lines [diffuse large B cell lymphoma (DLBCL), n.=27; mantle cell lymphoma (MCL), n.=10; anaplastic large T-cell lymphoma, n.=5; marginal zone lymphomas, n=6, others, n=6] were exposed to increasing doses of IMGN529 or to the unconjugated DM1 for 72h. Cell proliferation was measured using the MTT. Apoptosis induction was defined by at least 1.5-fold increase in caspase 3/7 signal activation with respect to controls using the Promega ApoTox-Glo Triplex Assay. CD37 surface expression was assessed by cytofluorimetry. Gene expression profiling (GEP) was done with the Illumina HumanHT-12 Expression BeadChips on untreated cell lines followed by GSEA (NES > |2|, P<0.05, FDR<0.25) and limma t-test (FC> |1.2|; P< 0.05; top 200 up and top 200 down). Results. The IMGN529 median IC50 in the 54 cell lines was 780pM (95%C.I., 263pm-11.45nM). Activity was stronger (P<0.001) in B cell lymphoma cell lines (n= 46; median IC50=450pM; 95%C.I., 150-800pM) than in T cell lymphoma cell lines (n=8; median IC50=22.5nM; 95%C.I., 14-40nM). The median IC50 for DM1 was 30pM (C.I.95%, 20-40pM) with no differences between B and T cell lymphoma origin. IMGN529 induced apoptosis in 33/54 (61%) lymphoma cell lines. Surface CD37 expression was higher in cell lines derived from B than from T cells (P< 0.0001): IMGN529 IC50 values, but not of DM1, were negatively correlated with surface CD37 expression across all cell lines (R=-0.39; P= 0.018), but not within the individual B or T cell subgroups. Among B cell lines, DLBCL cell of origin, TP53 status or the presence of BCL2 translocation did not affect the sensitivity to IMGN529, while IC50s were higher in the presence of MYC translocation (P= 0.043). No association was seen between IMGN529-induced apoptosis or the sensitivity to DM1 with DLBCL cell of origin, TP53 status or the presence of BCL2 or MYC translocations. We then compared the baseline gene expression profiling of DLBCL cell lines that were highly sensitive to IMGN529 (IC50< 800pM; "S") versus less sensitive/resistant DLBCL cell lines (IC50>10nM, "R"), separately for germinal center B cell type (GCB) (S, n=11; R, n=8) and for activated B cell like (ABC) (S, n=4; R, n=3). In both DLBCL groups, MYC targets, genes involved in unfolded protein response, glycolysis and DNA repair were enriched in transcripts more expressed in R than S cell lines. Transcripts associated with low sensitivity included CD44, VIM, ANXA2, BCL2, ANXA2P1, HSP90B1, NFKBIZ, CDK6, BIRC5 in GCB and HSPA1B, HSP90AA1, CADM1, CD86, TUBB2A, TUBG1, NOTCH1 in ABC cell lines. HEBP1, PHB, PSME3, RNU6-15, RPL13 were more expressed in both GCB and ABC R. Genes involved in PI3K/AKT/mTOR, hypoxia, INF-gamma, TNFA signaling via NFKB and in complement were more expressed in S than in R cell lines. Genes associated with sensitivity to IMGN529 comprised: CD37 (IMGN529 target), CD79A, CHI3L2, FAM117B, LPAR5, NFATC1, PTPN22, RBM38, SGPP1, SLC6A16 in both GCB and ABC cell lines; BASP1, CXCR5, BIK, LY86, TLR10, CD86, LCK, CD22, PTPN22, BCL6, PIK3IP1, CDKN2A in GCB; AFF3, PIM1, MGMT, PDE4B, NFKBIE, SYK, FOXO1in ABC. Conclusions. IMGN529 showed a very strong anti-tumoral activity in pre-clinical lymphoma models. High expression of CD37 and mostly genes involved in BCR signalling were associated with sensitivity to IMGN529. Conversely, the presence of MYC translocation, a high expression of MYC targets and of genes known to be involved in drug resistance (BCL2, BIRC5, CDK6, heat-shock proteins, annexins, proteasome and tubulin components) appeared to negatively affect the response to the ADC but also represent therapeutic targets for novel combinations to be explored. Disclosures Rossi: Gilead: Honoraria, Research Funding; Abbvie: Honoraria; Janseen: Honoraria. Sloss:Immunogen Inc: Employment.

scholarly journals Overcoming resistance to targeted therapies in chronic lymphocytic leukemia

2021 ◽  
Vol 5 (1) ◽  
pp. 334-343
Author(s):  
Sigrid S. Skånland ◽  
Anthony R. Mato
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
B Cell ◽  
Targeted Therapies ◽  
Rational Design ◽  
Treatment Options ◽  
Critical Role ◽  
Acquired Resistance ◽  
B Cell Lymphoma ◽  
Lymphocytic Leukemia ◽  
T Cell Therapy

Abstract Insight into the critical role of B-cell receptor signaling for the pathogenesis of chronic lymphocytic leukemia (CLL) led to the development of targeted therapies directed at key regulators of cell survival. Agents targeting B-cell lymphoma-2 protein, Bruton’s tyrosine kinase (BTK), and phosphatidylinositol 3-kinase are approved for treatment of CLL, and have significantly improved the disease management. Nevertheless, acquired resistance to the targeted therapies is a challenge still to be resolved. The mechanisms underlying resistance are becoming clearer, and include secondary mutations within the drug target and activation of bypass pathways. This knowledge has allowed development of strategies to prevent and overcome treatment resistance. Approaches to prevent resistance include targeting bypass mechanisms by combination therapies, temporally sequencing of therapies, improved clinical trial designs, and real-time monitoring of patient response. A rational design of drug sequencing may secure effective treatment options at the relapsed setting. Next-generation inhibitors and bispecific antibodies have the potential to overcome resistance to the BTK inhibitor ibrutinib. Immunotherapy, including chimeric antigen receptor-modified T-cell therapy, is explored for relapsed CLL. Here, recent advances that have contributed to the understanding of resistance to targeted therapies in CLL are discussed. Strategies for managing resistance are reviewed, including translational, real-world, and clinical perspectives.

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