scholarly journals Blockade of Ubiquitin Receptor PSMD4/Rpn10 Triggers Cytotoxicity and Overcomes Bortezomib-Resistance in Multiple Myeloma

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3211-3211
Author(s):  
Yan Song ◽  
Arghya Ray ◽  
Dharminder Chauhan ◽  
Kenneth Anderson

Abstract Background and Rationale Proteasome inhibitors (PIs) are standard of care therapy for patients diagnosed with multiple myeloma (MM). However, prolonged treatment can be associated with toxicity and development of drug resistance. Our research efforts have therefore focused on designing therapeutic strategies that can overcome PI-resistance. In this context, our RNA-interference-based loss-of-function studies have identified 19S proteasome-associated Ubiquitin Receptor (UbRs) Rpn10 and Rpn13 as potential therapeutic targets. Both Rpn10 and Rpn13 UbRs are associated with the 19S regulatory lid of the proteasome that recognizes ubiquitylated proteins marked for degradation by 20S core particle. We have previously reported the role of Rpn13 in MM (Song et., al Luekemia 2016 Sep;30(9):1877-86). Here we functionally characterized the role of Rpn10 in MM. Materials and Methods Cytotoxicity assays were performed using a panel of MM cell lines, primary patient cells, and peripheral blood mononuclear cells (PBMCs) from normal healthy donors. Cell viability was assessed using WST-1, MTT, and Cell Titer-Glo assay.Signal transduction pathways were evaluated using immunoblotting. Proteasome activity was measured as previously described (Chauhan et al., Cancer Cell 2005, 8:407-419; Chauhan et al., Cancer Cell 2012, 22(3):345-358). Statistical significance of data was determined using a Student's t test. Results Functional characterization of Rpn10 in MM:Gene expression (GEP) analysis showed inverse correlation between Rpn10 and overall patient survival (n=175) (p= 0.00064). Immunoblot analysis showed high Rpn10 protein levels in primary patient cells and MM cell lines versus normal plasma cells or PBMCs. Rpn10 knockdown by siRNA significantly decreased MM cell viability in both bortezomib-sensitive and -resistant MM cell lines. To assess the Rpn10 function, we generated a doxycycline-inducible Rpn10-shRNA knockout stable MM cell line. Rpn10-shRNA knockdown decreased MM cell proliferation. Mechanistic studies show that Rpn10 knockdown-triggered MM cell death is associated with 1) accumulation of cells in early and late apoptotic phase; 2) increase in polyubiquinated proteins; 3) arrest of cell cycle; 4) induction of ER stress; and 5) activation of caspases mediating apoptotic pathways. In order to determine if blockade of Rpn10 affects cellular proteasome function, we next utilized a reporter cell line expressing ubiquitin-tagged GFP that is constitutively targeted for proteasomal degradation. Interestingly, Rpn10-siRNA increased accumulation of the Ub-GFP reporter, reflecting impaired proteasome-mediated protein degradation. Finally, treatment of MM cells with peptides targeting UIM2 domain of Rpn10 significantly decreased MM cell viability, suggesting a potential therapeutic approach in MM. ConclusionOur preclinical data validates targeting 19S proteasome ubiquitin receptor Rpn10 upstream of the proteasome in the ubiquitin proteasomal cascade, and provides the framework for clinical evaluation of Rpn10 inhibitors to overcome PI resistance and improve patient outcome in MM. Disclosures Anderson: C4 Therapeutics: Equity Ownership, Other: Scientific founder; Celgene: Consultancy; Bristol Myers Squibb: Consultancy; Gilead: Membership on an entity's Board of Directors or advisory committees; Millennium Takeda: Consultancy; OncoPep: Equity Ownership, Other: Scientific founder.

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 3290-3290
Author(s):  
Deepika Sharma Das ◽  
Yan Song ◽  
Arghya Ray ◽  
Mehmet K. Samur ◽  
Nikhil C. Munshi ◽  
...  

Abstract Introduction Deregulation of the ubiquitin-proteasome system (UPS) is linked to pathogenesis of various human diseases, including cancer. Targeting the proteasome is an effective therapy in multiple myeloma (MM) patients.Recent research efforts led to the discovery of newer agents that target enzymes modulating protein ubiquitin- conjugation/deconjugation rather than the proteasome itself, with the goal of generating more specific and less toxic anti-tumor therapies. Our prior studies have identified a role of deubiquitylating enzymes (DUBs) USP7, USP14, and UCHL5 in MM pathogenesis, and provided the rationale for targeting these DUBs in MM (Chauhan et al., Cancer Cell 2012, 11:345-358). Among DUBs, USP1 regulates DNA repair and the Fanconi anemia pathway by deubiquitylating two critical DNA repair proteins, FANCD2-Ub and PCNA-Ub. Additionally, USP1 stabilizes tumor-promoting inhibitor of DNA binding (ID) proteins. Here we examined the role of USP1 DUB in MM using both biochemical and RNA interference strategies. Methods We utilized MM cell lines, patient cells, and peripheral blood mononuclear cells (PBMCs) from normal healthy donors. Cell viability was assessed using WST and CellTiter-Glo assays. MM.1S cells were transiently transfected with control short interfering RNA (siRNA) USP1 ON TARGET plus SMART pool siRNA using the cell line Nucleofector Kit V. A biochemical inhibitor of USP1 SJB3-019A (SJB) was purchased from Medchem Express, USA. In vitro DUB enzymatic activity was assessed using Ubiquitin-AMC and Ubiquitin-Rhodamine assay kits, as well as Ub-CHOP-reporter and K48-linked Ubiquitin tetramers. Competitive Ub-VS probe labeling was performed, as previously described (Chauhan et al., Cancer Cell 2012, 11:345-358). Signal transduction pathways were evaluated using immunoblotting. Statistical significance of data was determined using a Student's t test. Results Gene expression profiling (GEP) analysis of USP1 showed significantly higher USP1 levels in patient MM cells versus normal plasma cells (p < 0.05).We found a statistically significant inverse correlation between USP1 levels and overall patient survival (p =0.036). Immunoblot blot analysis show higher USP1 levels in MM cell lines and patient cells compared to normal cells.USP1 knock-down reduced MM cell viability (p < 0.05).To validate our siRNA data, we utilized a novel USP1 inhibitor SJB3-019A (SJB). Analysis using Ub-Rhodamine, Ub-AMC and Ub-EKL reporter assays showed that SJB is a potent, specific, and selective inhibitor of cellular USP1 DUB activity (EC50=1μM), and does not inhibit other DUBs (USP2/USP5/USP7/USP14) or other families of cysteine proteases (UCH37) (EC50 >10 μM). SJB blocks labeling of USP1 with HA-Ub-VS probe in a concentration-dependent manner, but did not alter labeling of other DUBs with HA-Ub-VS. SJB inhibits USP1-mediated cleavage of K48-linked Tetra-ubiquitin chains, but not that mediated by USP2 or USP7. Treatment of MM cell lines (MM.1S, MM.1R, RPMI-8226, Dox-40, ARP1, KMS11, U266, ANBL6.WT, ANBL6.BR and LR5) and primary patient cells for 24h significantly decreases their viability (IC50 range 100nM to 500nM) (p< 0.05; n=3) without markedly affecting PBMCs from normal healthy donors, suggesting selective anti-MM activity and a favorable therapeutic index for SJB. Tumor cells from 4 patients whose disease was progressing while on bortezomib, dexamethasone, and lenalidomide therapies were sensitive to SJB. Furthermore, SJB3-019A inhibits proliferation of MM cells, even in the presence of BM stromal cells and plasmacytoid dendritic cells. Mechanistic studies show that SJB3-019A- triggered apoptosis is associated with 1) induction of cell cycle arrest via p21 upregulation; 2) activation of caspase 3, caspase-8 and caspase-9; 3) decreased homologous recombination activity and increased levels of Ub-FANCD2, Ub-FANCI, and Ub-PCNA; 4) defective DNA repair, evident by reduced RAD51; 5) degradation of USP1 and ID proteins; and 6) downregulation of Notch-1, Notch-2, SOX-4, and SOX-2 proteins. Finally, combination of SJB with lenalidomide, pomalidomide, HDACi ACY-241, or bortezomib induces synergistic anti-MM activity and overcomes drug resistance. Conclusion Our preclinical studies provide the framework for clinical evaluation of USP1 inhibitors, alone or in combination, as a potential novel MM therapy. Disclosures Munshi: Celgene Corporation: Consultancy; Pfizer: Consultancy; Merck: Consultancy; Oncopep: Consultancy, Equity Ownership; Takeda: Consultancy. Chauhan:Stemline Therapeutics, Inc.: Consultancy; C4 Therapeutics: Equity Ownership; Oncopeptide AB: Consultancy; Epicent Rx: Consultancy. Anderson:Celgene Corporation: Consultancy; Millennium Pharmaceuticals: Consultancy; Novartis AG: Consultancy; Bristol-Myers Squibb:: Consultancy; Oncopep: Other: Scientific Founder; Acetylon: Other: Scientific Founder.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3207-3207 ◽  
Author(s):  
Michael J Thomenius ◽  
Jennifer Totman ◽  
Kat Cosmopoulos ◽  
Dorothy Brach ◽  
Lei Ci ◽  
...  

Abstract t(4;14) chromosome translocations are found in 15% of newly diagnosed multiple myeloma (MM) cases and are associated with high risk. MM cells with t(4;14) over-express the histone methyltransferase (HMT), WHSC1/MMSET/NSD2, which leads to deregulation of gene expression due to increased di-methylation of Histone H3 at lysine 36 (H3K36me2). This activity has been shown to be essential for the survival of t(4;14) MM cells. In addition to WHSC1, another HMT, SETD2, has been shown to methylate H3K36. SETD2 is the only known enzyme capable of tri-methylation of H3K36 and has been reported to play a role in transcriptional elongation and alternative splicing. CRISPR pooled screening has shown that SETD2 activity is required for viability of a variety of cancer cell lines. This led Epizyme to develop small molecule inhibitors of SETD2 enzyme activity in order to understand the role of SETD2 in tumorigenesis. Through our drug discovery efforts, we identified EPZ-040414, a potent and selective inhibitor of SETD2 with low nM cell biochemical activity and broad selectivity against a panel of other HMTs. The proposed role of SETD2 in H3K36 methylation led us to test a panel of MM cells, including 6 t(4;14) cell lines with EPZ-040414. Inhibition of SETD2 resulted in reduced global tri-methylation of H3K36 in t(4;14) bearing MM cell lines. In contrast, there was no effect on global di-methyl H3K36 levels, indicating that WHSC1 activity is not affected by SETD2 inhibition. Moreover, 5/6 t(4;14) MM cell lines showed a cytotoxic response to treatment with EPZ-040414 with IC50s ranging between 60 and 200 nM, while all non-t(4;14) MM cell lines showed limited responses between 1 and 8 μM. Moreover, screening of a 280 cancer cell line panel with a SETD2 inhibitor showed minimal anti-proliferative activity in most cell lines tested. These findings show that t(4;14) MM cell lines require SETD2 activity for survival, suggesting that SETD2 inhibitors are strong candidates for the treatment of this high risk subgroup of MM. Efforts to further understand the interaction between SETD2 and WHSC1 in the molecular pathogenesis of t(4;14) myeloma will be presented. The current chemical series represented by EPZ-040414 is potent, selective, orally available, and currently under further evaluation for its therapeutic potential. Figure. Figure. Disclosures Thomenius: Epizyme Inc.: Employment, Equity Ownership. Totman:Epizyme Inc.: Employment, Equity Ownership. Cosmopoulos:Epizyme Inc.: Employment, Equity Ownership. Brach:Epizyme Inc.: Employment, Equity Ownership. Ci:Epizyme Inc.: Employment, Equity Ownership. Farrow:Epizyme Inc.: Employment, Equity Ownership. Smith:Epizyme Inc.: Employment, Equity Ownership. Chesworth:Epizyme Inc.: Employment, Equity Ownership. Duncan:Epizyme Inc.: Employment, Equity Ownership. Tang:Epizyme Inc.: Employment, Equity Ownership. Riera:Epizyme Inc.: Employment, Equity Ownership. Lampe:Epizyme Inc.: Employment, Equity Ownership.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 419-419
Author(s):  
Yan Song ◽  
Deepika Sharma Das ◽  
Arghya Ray ◽  
Durgadevi Ravillah ◽  
Nikhil C. Munshi ◽  
...  

Abstract Background and Rationale Deregulation of the ubiquitin-proteasome system (UPS) is linked to pathogenesis of various human diseases, including cancer. Targeting the proteasome is an effective therapy in multiple myeloma (MM) patients. Recent research efforts led to the discovery of newer agents that target enzymes modulating protein ubiquitin-conjugation/deconjugation rather than the proteasome itself, with the goal of generating more specific and less toxic antitumor therapies. Ubiquitylation is a dynamic reversible process coordinated by many enzymes: ubiquitin ligases attach ubiquitin to proteins allowing for their degradation, whereas deubiquitylating enzymes deconjugate ubiquitin from target proteins, thereby preventing their proteasome-mediated degradation. RPN13 is ubiquitin receptor within the 19S regulatory particle lid of the proteasome that recognizes ubiquitylated proteins marked for degradation by 20S core particle. Here we examined the role of RPN13 in MM using both biochemical and RNA interference strategies. Materials and Methods We utilizedMM cell lines, patient tumor cells, and peripheral blood mononuclear cells (PBMCs) from normal healthy donors. Drug sensitivity/cell viability and apoptosis were assessed using XTT/MTT and Annexin V staining, respectively. MM.1S cells were transiently transfected with control short interfering RNA (siRNA), RPN13 siRNA ON TARGET plus SMART pool siRNA using the cell line Nucleofector Kit V. Synergistic/additive anti-MM activity was assessed by isobologram analysisusing “CalcuSyn” software program. Signal transduction pathways were evaluated using immunoblotting. Proteasome activity was measured as previously described (Chauhan et al., Cancer Cell 2005, 8:407-419). Statistical significance of data was determined using a Student’s t test. RA190 was purchased from Xcess Biosciences, USA; and bortezomib, lenalidomide, and pomalidomide were purchased from Selleck chemicals, USA. Results Analysis of RPN13/ADRM1 expression showed a significantly higher level in primary patient MM cells (n=73) versus normal plasma cells (n=15) (p < 0.004). Similarly, immunoblot analysis showed elevated RPN13 in MM cells versus normals. RPN13 siRNA knockdown significantly decreased MM cell viability (p < 0.001; n=3). To further validate our siRNA data, we utilized recently reported novel agent RA190 (bis-benzylidine piperidone) that targets RPN13. RA190 inhibits recognition of polyubiquitylated proteins and their deubiquitylation, which in turn prevents their degradation (Anchoori et al., Cancer Cell 2013, 24:791). Treatment of MM cell lines (MM.1S, MM.1R, RPMI-8226, ARP-1, ANBL6.WT, and ANBL6.BR) and primary patient cells for 48h significantly decreased their viability (IC50 range 200nM to 600nM; p < 0.001 for all cell lines; n=3) without markedly affecting PBMCs from normal healthy donors, suggesting specific anti-MM activity and a favorable therapeutic index for RA190. Tumor cells were obtained from patients whose disease was progressing while on bortezomib, dexamethasone, and lenalidomide therapies. Moreover, the cytotoxicity of RA190 was observed in MM cell lines sensitive and resistant to conventional (dex) and novel (bortezomib) therapies. Furthermore, RA190 inhibits proliferation of MM cells even in the presence of BM stromal cells. Mechanistic studies show that RA190-triggered MM cell death is associated with 1) accumulation of cells in early and late apoptotic phase; 2) increase in polyubiquinated proteins; and 3) activation of caspases mediating both intrinsic and extrinsic apoptotic pathways. Importantly, RA190-induced apoptosis in MM cells occurs in a p53-independent manner, since RA190 triggered significant apoptosis in both p53-null (ARP-1) and p53-mutant (RPMI-8226) MM cells (p < 0.004). Finally, combining RA190 with lenalidomide, pomalidomide, or bortezomib induces synergistic/additive anti-MM activity, and overcomes drug resistance. Conclusion Our preclinical data showing efficacy of RA190 in MM disease models validates targeting ubiquitin receptors upstream of the proteasome in the ubiquitin proteasomal cascade to overcome proteasome inhibitor resistance, and provides the framework for clinical evaluation of RPN13 inhibitors to improve patient outcome in MM. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1813-1813
Author(s):  
Deepika Sharma Das ◽  
Yan Song ◽  
Arghya Ray ◽  
Paul Richardson ◽  
Dharminder Chauhan ◽  
...  

Abstract Introduction Proteasome inhibitor Bortezomib is effective therapy of relapsed/refractory and newly diagnosed multiple myeloma (MM); however, dose-limiting toxicities and the development of resistance limit its long-term utility. Importantly, the ability of bortezomib to overcome resistance to conventional therapies has validated therapeutically targeting the Ubiquitin Proteasome System (UPS), and suggested potential utility of inhibitors of other components of the UPS including deubiquitylating enzymes (DUBs). Therapeutic strategies directed against DUBs may allow for more specific targeting of the UPS, and therefore be less likely to have off-target activities with associated toxicities. Our prior studies have identified a role of USP7, USP14, and UCHL5 in MM pathogenesis, and provided the rationale for targeting these DUBs in MM (Chauhan et al., Cancer Cell 2012, 11:345-358; Tian et al., Blood 2014, 123:706-716). Among DUBs, USP1 regulates DNA repair and the Fanconi anemia pathway through its association with its WD40 binding partner UAF1, and through its deubiquitylation of two critical DNA repair proteins, FANCD2-Ub and PCNA-Ub. Here we examined the role of USP1 DUB in MM using both biochemical and RNA interference strategies. Methods We utilized MM cell lines, patient cells, and peripheral blood mononuclear cells (PBMCs) from normal healthy donors. Cell viability was assessed using WST and CellTiter-Glo assays. MM.1S MM cells were transiently transfected with control short interfering RNA (siRNA), USP1 ON TARGET plus SMART pool siRNA using the cell line Nucleofector Kit V. A biochemical inhibitor of USP1 SJB3-019A (SJB) was purchased from Medchem Express, USA. In vitro DUB enzymatic activity was assessed using Ubiquitin-AMC and Ubiquitin-Rhodamine assay kits, as well as Ub-CHOP-reporter and K48-linked Ubiquitin tetramers. Competitive Ub-VS probe labeling was performed, as previously described (Chauhan et al., Cancer Cell 2012, 11:345-358). Signal transduction pathways were evaluated using immunoblotting. Statistical significance of data was determined using a Student's t test. Results Immunoblot analyses show higher USP1 levels in MM cell lines and patient cells than normal cells.USP1-siRNA inhibited MM cell proliferation, which was rescued by transfection of USP1 (WT). Using Ub-Rhodamine, Ub-AMC, and Ub-EKL reporter assays, we found higher USP1 deubiquitylating activity in patient MM cells versus normal cells, suggesting a favorable therapeutic index for targeting USP1. Importantly, siRNA-knockdown of USP1 both promoted degradation of tumorigenic ID1 protein, and inhibited proliferation of bortezomib-resistant (ANBL-6.BR) MM cells, suggesting that novel agents targeting USP1 may overcome bortezomib resistance. We next examined the effects of USP1 inhibitor SJB3 on MM cell growth and survival in our models of MM. Analysis using Ub-Rhodamine, Ub-AMC, and Ub-EKL reporter assays in a panel of MM cell lines showed that SJB is a potent, specific, and selective inhibitor of USP1 DUB activity (EC50 = 50 ± 5.7 nM), which does not inhibit other DUBs (USP2/USP5/USP7/USP14) or other families of cysteine proteases (EC50>100 μM). SJB blocks labeling of USP1 with HA-Ub-VS probe in a concentration-dependent manner, but did not alter labeling of other DUBs with HA-Ub-VS. SJB inhibits USP1-mediated cleavage of K48 linked polyubiquitin chains, but not that mediated by USP2 or USP7. Treatment of MM cell lines (MM.1S, MM.1R, RPMI-8226, Dox-40, ARP1, KMS11, U266, ANBL6.WT, ANBL6.BR, and LR5) and primary patient cells for 24h significantly decreases their viability (IC50 range 100nM to 500nM) (p < 0.05; n=3) without markedly affecting PBMCs from normal healthy donors, suggesting specific anti-MM activity and a favorable therapeutic index for SJB. Tumor cells from 3 of 5 patients were obtained from patients whose disease was progressing while on bortezomib, dexamethasone, and lenalidomide therapies. Mechanistic studies show that SJB-triggered apoptosis is associated with degradation of USP1 and Id1 protein. Finally, combination of SJB with lenalidomide, pomalidomide, HDACi ACY-1215, or bortezomib both induces synergistic anti-MM activity and overcomes drug resistance. Conclusion Our preclinical studies provide the framework for clinical evaluation of USP1 inhibitors, alone or in combination, as a potential MM therapy. Disclosures Chauhan: Stemline Therapeutics: Consultancy.


2016 ◽  
Vol 64 (4) ◽  
pp. 950.1-950 ◽  
Author(s):  
SH Afroze ◽  
DC Zawieja ◽  
R Tobin ◽  
C Peddaboina ◽  
MK Newell-Rogers ◽  
...  

ObjectiveCinobufotalin (CINO), a cardiotonic steroid (CTS) or bufadienolide, is extracted from the skin secretions of the traditional Chinese medicine giant toads (Chan su). CINO has been used as a cardiotonic, diuretic and a hemostatic agent. Previously we have shown that CINO inhibits the cytotrophoblast cell function. Recently other study has shown that CINO inhibits A549, a lung cancer cell function. In this study, we assessed the effect of CINO on three different ovarian cancer cell lines; SK-OV-3, CRL-1978 and CRL-11731 to confirm whether the effect of CINO is cell specific.Study DesignWe evaluated the effect of CINO on three ovarian cancer cells SK-OV-3, CRL-1978, and CRL-11731 function in vitro. Each Cell lines were treated with different concentrations of CINO (0.1, 1, 5 and 10 µM). For each cell line cell proliferation, migration and invasion were measured by using a CellTiter Assay (Promega), Cytoselect Assay (Cell Biolabs) and by using a FluoroBlock Assay (BD) respectively. Proliferating Cell Nuclear Antigen (PCNA) was also evaluated in cell lysates of CINO treated these 3 ovarian cancer cells by western blot analysis. Cell Cycle arrest and Cell viability were determined by fluorescence-activated cell sorting (FACS) analysis. We also performed Annexin V staining on CINO treated these 3 ovarian cancer cell lines by immunofluorescence to evaluate the pro-apoptotic protein expression. In addition mitochondrial membrane potential has also been measured for all these 3 ovarian cell lines after CINO treatment using MMP kit, by FACS analysis.ResultsConcentration of CINO at 0.5 µM inhibit SK-OV-3, CRL-1978, and CRL-11731 ovarian cancer cells proliferation, migration and invasion without cell death and loss of cell viability but cell viability differs for each cell line. Each cell lines differ in response to CINO doses for PCNA expression as well as Annexin V pro-apoptotic protein expression. CINO decreases mitochondrial membrane potential for SK-OV-3 but for CRL-1978 and CRL-11731 increases in response to CINO treatment.ConclusionCINO is cell specific, as each cancer cell line responds differently. These data demonstrate that the mode of action of CINO is different on these 3 types of ovarian cancer cells.


2021 ◽  
Author(s):  
Maged Mostafa Mahmoud ◽  
Ahmed M. Al-Hejin ◽  
Turki S. Abujamel ◽  
Modhi Alenezi ◽  
Fadwa Aljoud ◽  
...  

Abstract This study served as the pioneer in studying the anti-cancer role of chicken cathelicidin peptides. Chicken cathelicidins were used as anticancer agent against the breast cancer cell line (MCF-7) and human colon cancer cell line (HCT116). An in vivo investigation was also achieved to evaluate the role of chicken cathelicidin in Ehrlich ascites cell (EAC) suppression as a tumor model after subcutaneous implantation in mice. In addition, the mechanism of action of the interaction of cationic peptides with breast cancer cell line MCF-7 was also investigated. It was found during the study that exposure of cell lines to higher concentration of chicken cathelicidin for 72 h reduced cell lines growth rate by 90%-95%. These peptides demonstrated down-regulation of (cyclin A1 and cyclin D genes) which are essential for G1/S phase transient and S/G2 phase and consequently causes “prometaphase arrest” ultimately leading to death of MCF-7 cells. The study showed two- and three-times higher expression of the caspase-3, and − 7 genes respectively in MCF-7 cells treated with chicken peptides (especially cathelicidin-2 and − 3) relative to untreated cells which encouraged pro-apoptotic pathway, autophagy, and augmentation of the anti-proliferative activity. Our data showed that chicken ( CATH-1 ) enhance releasing of TNFα, INF-γ and upregulation of granzyme K in treated mice groups, in parallel, the tumor size and volume was reduced in the treated EAC-bearing groups after cathelicidin administration compared to untreated EAC-bearing group. Additionally, animals received high dose of cathelicidin-1 (40 µg/ml) displayed an apical survival rate compared to untreated carcinoma control and animals which received low dose of cathelicidin (10 and 20 µg/ml). Tumor of mice groups treated with chicken cathelicidin displayed high area of necrosis compared to untreated EAC-bearing mice. Based on histological analysis and immunohistochemical staining revealed that the tumor section in Ehrlich solid tumor exhibited a strong Bcl2 expression in untreated control compared to mice treated with 10 & 20 µg/ml of cathelicidin. Interestingly, low expression of Bcl2 were observed in mice taken 40 µg/ml of CATH-1. This study drive intention in treatment of cancer through the efficacy of anticancer efficacy of chicken cathelicidin peptides.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5148-5148
Author(s):  
Andoni Garitano-Trojaola ◽  
Eva Teufel ◽  
Matteo Claudio Da Via' ◽  
Ana Sancho ◽  
Nadine Rodhes ◽  
...  

Abstract Secondary Acute Myeloid Leukemia (sAML) accounts for 10-30% of all AML. It arises from a preexisting clonal disorder of hematopoiesis, such as myelodysplastic syndromes (MDS) or chronic myeloproliferative neoplasia (cMPN) in most cases (60-70%) or from exposure to a leukemogenic agent e.g. chemotherapy. sAML is generally considered to be of unfavorable prognosis, as treatment sensitivity is reduced, compared to de novo AML (dnAML) and overall survival is shortened. The incidence of AML associated NRAS are similar between sAML and dnAML (10 to 15%, Jelena D. Milosevic et al.). Prognostic impact of such mutations have been controversially discussed, but have been linked to favorable response to high dose cytarabine treatment in dnAML patients (Andreas Neubauer et al.), thus providing the first example of an oncogenic mutation impacting drug response in dnAML. This effect, however, has not yet been shown in sAML, therefore the aim of this work is to study the role of mutated NRAS in the response to chemotherapy and the hypomethylating agent (HMA) 5-azacitidine in sAML. We utilized two sAML cell lines SET-2 and HEL (both NRAS wildtype) in which we stably introduced the NRAS WT and the known activating hotspot mutation NRAS G12D using the sleeping Beauty technology. The dose-response assays of conventional chemotherapy and 5-azacitidine were carried out in the parental cell lines (SET-2/HEL) compared to NRAS WT (SET-2 NRAS WT/HEL NRAS WT) and NRAS G12D (SET-2 NRAS G12D/HEL NRAS G12D). In contrast to our expectations, both NRAS G12D mutation harboring cell lines, SET-2 and HEL developed resistance to cytarabine, idarubicin and 5-azacytidine, whereas the ones with wildtype NRAS remained susceptible to the drugs. To reverse the resistance we tested the MEK inhibitors Binimetinib and Trametinib in our SET-2 NRAS G12D cell line model according to recent reports about preclinical efficacy of MEK inhibition in NRAS mutant dnAML cells (Michael R. Burgess et al.). And in fact, single agent Binetimib and Trametinib treatments reduced cell viability by 20% at 48 hours. Strikingly, in combination with 5-azacitidine, Binimetinib and Trametinib treatments led to a viability reduction by 90%. Next we induced necroptosis in our NRAS mutant cell line models through the combination of Birinapant (SMAC mimetics) and Emricasan (Inhibitor of Caspase 8), as recently described by Brumatti et al. and were, in addition, able to reduce the cell viability by 60 %. In summary, we provide first evidence, that in contrast to dnAML, activating NRAS mutations may promote resistance to conventional chemotherapy and 5-azacitidine in sAML cell lines. Furthermore we were able to demonstrate, that the combination of MEK inhibitors (Binimetinib and Trametinib) and 5-azacitidine as well as the induction of necroptosis such as the combination birinapant and emricasan, may provide a potential strategy to overcome the resistance. Disclosures Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 857-857
Author(s):  
Chandraditya Chakraborty ◽  
Eugenio Morelli ◽  
María Linares ◽  
Kenneth C. Anderson ◽  
Mehmet Kemal Samur ◽  
...  

Multiple myeloma (MM) is a complex hematological malignancy characterized by gene pathway deregulations. Initial sequencing approaches have failed to identify any single frequent (&gt;25%) mutation in the coding genome. We, therefore performed a deep (average coverage &gt; 80X) whole genome sequencing (WGS) on 260 MM samples (208 newly diagnosed and 52 first relapse after uniform treatment) to comprehensively identify recurrent somatic alterations in non-coding regions. We have identified the most frequently involved genes affected by perturbation in neighboring non-coding region and integrate their expression using our matching deep RNA-seq data from the same patients. One of the most prominent examples is mutations in the 5' untranslated region and intron 1 of the BCL7A gene in 76% of myeloma patients. Integration of WGS with RNA-seq data confirmed significant downregulation of its expression (p values &lt; 1e-5) in the MM cells as compared to normal plasma cells (PC). This led us to investigate the consequences of BCL-7A loss in MM. To evaluate the role of BCL7A in MM, using gain of- (GOF) and loss-of-function (LOF) approaches, we have utilized a large panel of MM cell lines with differential expression of BCL7A at the RNA and protein levels. Ectopic expression of BCL7A in a panel of 3 MM cell lines with low basal levels of BCL7a significantly reduced cell viability and colony formation over time. Inhibition of cell viability was associated with induction of apoptotic cell death in the BCL7A overexpressing cells compared to control cells. LOF studies in 3 MM cell lines with relatively higher expression of BCL7a using 3 BCL7A-specific shRNA constructs showed a more proliferative phenotype, with increased growth and viability and enhanced colony formation. The effects of BCL7A loss in MM cells were further confirmed using CRISPR-Cas9 system. BCL7a-KO cells had higher proliferative rate compared to WT cells and add back of lentiviral BCL7a plasmid reversed this effect. BCL7A is part of the SWI/SNF chromatin remodeling complex. Mutations in the genes encoding m-SWI/SNF subunits are found in more than 20% of human cancers, with subunit- and complex-specific functions. We confirmed that when expressed, BCL7A interacts with BCL11A into the SWI/SNF complex in MM cells. Comparative, mass spectrometry analysis in fact revealed SMARCC2 (BAF170), an integral subunit of SWI/SNF complex, to bind with BCL7A-BCL11A complex. However, BCL7A loss causes decreased SMARCC2 incorporation into SWI/SNF, thus suggesting that presence of BCL7A is crucial in the formation of SWI/SNF complex in MM cells and might play an important role in chromatin remodeling. Interestingly, oncogenes DEK (DNA binding oncogene) and TPD52 (tumor protein D52) involved in cancer cell proliferation and chromatin remodeling formed complex with BCL11A in BCL7A KO MM cells. Additionally, several anti-apoptotic proteins such as ANXA-1 and BCL2 are in complex with BCL11A when BCL7A is lost, suggesting the formation of an anti-apoptotic complex with consequences on MM cell survival. Currently ongoing studies are investigating the molecular mechanism of non-coding mutations impacting BCL7A expression and pathways affected by its downregulation with impact on MM cell growth and survival. In conclusion, we report biological consequences of a frequent (&gt;75% patients) non-coding mutation in MM with cellular and molecular effects of BCL7A loss in which implicates a functional role of the m-SWI/SNF complex in driving a MM cell proliferative phenotype. Disclosures Anderson: Gilead Sciences: Other: Advisory Board; Janssen: Other: Advisory Board; Sanofi-Aventis: Other: Advisory Board; C4 Therapeutics: Other: Scientific founder ; OncoPep: Other: Scientific founder . Munshi:Abbvie: Consultancy; Abbvie: Consultancy; Amgen: Consultancy; Amgen: Consultancy; Adaptive: Consultancy; Adaptive: Consultancy; Celgene: Consultancy; Janssen: Consultancy; Janssen: Consultancy; Takeda: Consultancy; Takeda: Consultancy; Oncopep: Consultancy; Oncopep: Consultancy; Celgene: Consultancy.


2020 ◽  
Vol 19 (4) ◽  
pp. 691-698
Author(s):  
Lin I-Ju ◽  
Tian YongJie

Purpose: The purpose of this study was to evaluate the role of miR-624-5p in ovarian cancer.Methods: MiR-624-5p expression in ovarian cancer {OC) cell lines and normal cells (NCs) was evaluated and compared the differential miR-624-5p in OC A2780 cells and cisplatin-resistant OC cell line (A2780/DDP). CCK-8 was used to evaluate changes in cell viability of the A2780 and A2780/DDP cell lines as well as silenced miR-624-5p. Western Blot examined the Stat3 and phosphorylated Pi3k. The binding between PDGFRA and miR-624-5p was predicted on Targetscan and verified through Luciferase Reporter Assay. The role of PDGFRA in A2780/DDP by overexpressing PDGFRA was evaluated by RT-qPCR and CCK-8 assays. RT-qPCR assay also measured miR-624-5p expression responsive to different dosages of cisplatin and CCK8 examined viability levels correspondingly. In addition, the interplay of PDGFRA and miR-624-5p by combined downregulation of both miR-624-5pand PDGFRA were evaluated.Results: OC cells had higher miR-624-5p expression than NCs but lower compared to cisplatinresistant A2780/DDP cells. A2780/DDP cells had higher viability than OC cell line A2780. Stat3 and phosphorylated PI3K were activated in A2780/DDP cells. Silencing miR-624-5p led to lower viability inA2780/DDP cells. miR-624-5p expression dropped as the cisplatin concentration increased, resulting in decreasing viability respectively. Luciferase Reporter assay validated the binding of miR-624-5p and PDGFRA in A2780/DDP cells. Overexpressed PDGFRA induced lower cell viability in A2780/DDP cells. Downregulation of PDGFRA partially restored the lowered viability and inhibited Stat3 as well as phosphorylated Pi3k induced by miR-624-5p inhibitor.Conclusion: MiR-624-5p could add to the cellular resistance to cisplatin in OC in-vitro model, which indicated that it might help unveil the mystery of drug-resistance in clinical stage of ovarian cancer. Keywords: MiR-624-5p, resistance, cisplatin, PDGFRA/Stat3/PI3K, ovarian cancer


2019 ◽  
Vol 18 (14) ◽  
pp. 2032-2041 ◽  
Author(s):  
Nil Kılıç ◽  
Sümer Aras ◽  
Demet Cansaran-Duman

Objective: Breast cancer is one of the most common diseases among women worldwide and it is characterized by a high ratio of malignancy and metastasis and low rate of survival of patients. Due to limited treatment options, the discovery of alternative therapeutic agents and clarifying the molecular mechanism of breast cancer development may offer new hope for its treatment. Lichen secondary metabolites may be one of these therapeutic agents. Methods: In this study, the effects of Vulpinic Acid (VA) lichen secondary metabolite on the cell viability and apoptosis of breast cancer cells and non-cancerous cell line were investigated. Quantitative polymerase chain reaction was also performed to determine changes in the expression of apoptosis-related genes at a molecular level. Results: The results demonstrated that VA significantly inhibited the cell viability and induced apoptosis of human breast cancer cells. The highest rates of decreased growth were determined using the IC50 value of VA for 48h on MCF-7 breast cancer cell. Interestingly, VA treatment significantly reduced cell viability in all examined breast cancer cell lines compared to their non-cancerous human breast epithelial cell line. This is the first study on the investigation of the effects of VA on the molecular mechanisms associated with the expression of apoptosis-related genes in breast cancer cell lines. Results demonstrated that the gene expression of P53 genes was altered up to fourteen-fold levels in SK-BR-3 cell lines whereas it reached 2.5-fold in the MCF-12A cell line after treatment with VA. These observations support that VA induces apoptosis on the breast cancer cells compared with the non-cancerous human breast epithelial cell line. Conclusion: It is implicated that VA may be a promising novel molecule for the induction of apoptosis on breast cancer cells.


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