SMARCA4/2 loss inhibits chemotherapy-induced apoptosis by restricting IP3R3-mediated Ca2+ flux to mitochondria

AbstractInactivating mutations in SMARCA4 and concurrent epigenetic silencing of SMARCA2 characterize subsets of ovarian and lung cancers. Concomitant loss of these key subunits of SWI/SNF chromatin remodeling complexes in both cancers is associated with chemotherapy resistance and poor prognosis. Here, we discover that SMARCA4/2 loss inhibits chemotherapy-induced apoptosis through disrupting intracellular organelle calcium ion (Ca2+) release in these cancers. By restricting chromatin accessibility to ITPR3, encoding Ca2+ channel IP3R3, SMARCA4/2 deficiency causes reduced IP3R3 expression leading to impaired Ca2+ transfer from the endoplasmic reticulum to mitochondria required for apoptosis induction. Reactivation of SMARCA2 by a histone deacetylase inhibitor rescues IP3R3 expression and enhances cisplatin response in SMARCA4/2-deficient cancer cells both in vitro and in vivo. Our findings elucidate the contribution of SMARCA4/2 to Ca2+-dependent apoptosis induction, which may be exploited to enhance chemotherapy response in SMARCA4/2-deficient cancers.

Download Full-text

Ginsenoside Rg3 Prolongs Survival of the Orthotopic Hepatocellular Carcinoma Model by Inducing Apoptosis and Inhibiting Angiogenesis

Analytical Cellular Pathology ◽

10.1155/2019/3815786 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Shen Hu ◽

Yan Zhu ◽

Xiangyang Xia ◽

Xiaobo Xu ◽

Fen Chen ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Microvessel Density ◽

Tumor Model ◽

Oral Feeding ◽

Apoptosis Induction ◽

Ginsenoside Rg3 ◽

Kaplan Meier ◽

Induced Apoptosis

Aim. Microvessel density is a marker of tumor angiogenesis activity for development and metastasis. Our preliminary study showed that ginsenoside Rg3 (Rg3) induces apoptosis in hepatocellular carcinoma (HCC) in vitro. The aim of this study was to investigate the cross-link for apoptosis induction and antiangiogenesis effect of Rg3 on orthotopic HCC in vivo. Methods. The murine HCC cells Hep1-6 were implanted in the liver of mouse. With oral feeding of Rg3 (10 mg/kg once a day for 30 days), the quantitative analysis of apoptosis was performed by using pathology and a transmission electron microscope and microvessel density was quantitatively measured by immunohistochemical staining of the CD105 antibody. The mice treated with Rg3 (n=10) were compared with the control (n=10) using Kaplan-Meier analysis. Animal weight and tumor weight were measured to determine the toxicity of Rg3 and antitumor effect on an orthotopic HCC tumor model. Results. With oral feeding of Rg3 daily in the first 30 days on tumor implantation, Rg3 significantly decreased the orthotopic tumor growth and increased the survival of animals (P<0.05). Rg3-treated mice showed a longer survival than the control (P<0.05). Rg3 treatment induced apoptosis and inhibited angiogenesis. They contributed to the tumor shrinkage. Rg3 initialized the tumor apoptotic progress, which then weakened the tumor volume and its capability to produce the vascularized network for further growth of the tumor and remote metastasis. Conclusion. Rg3 inhibited the activation of microtumor vessel formation in vivo besides its apoptosis induction. Rg3 may be used as an adjuvant agent in the clinical HCC treatment regimen.

Download Full-text

The Mechanisms of Chansu in Inducing Efficient Apoptosis in Colon Cancer Cells

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/849054 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11 ◽

Cited By ~ 10

Author(s):

Chun Li ◽

Saeed M. Hashimi ◽

Siyu Cao ◽

Albert S. Mellick ◽

Wei Duan ◽

...

Keyword(s):

Colon Cancer ◽

Cancer Cells ◽

Surrogate Marker ◽

Apoptotic Pathway ◽

Lung Cancers ◽

Cancer Cell Death ◽

Prostate Cancers ◽

Induced Apoptosis

Chansu is one of the most widely used traditional Chinese medicines in China, Japan, and other Southeast Asian countries primarily for antipain, anti-inflammation, and recently anticancer. Over 10 recipes and remedies contained Chansu, which are easily available in pharmacies and hospitals, but the mechanisms of action were not clearly articulated. In the present study, Cinobufagin (CBF), the major compound of Chansu, was employed as a surrogate marker to determine its ability in inducing cancer cell death. As expected, CBF has significant cancer-killing capacity for a range of cancers, but such ability differs markedly. Colon and prostate cancers are more sensitive than skin and lung cancers. Interestingly, cancer cells die through apoptotic pathway either being biphasic caspase-3-dependent (HCT116) or independent (HT29). Multipathway analysis reveals that CBF-induced apoptosis is likely modulated by the hypoxia-inducing factor-1 alpha subunit (HIF-1α) as its inhibition was evidentin vitroandin vivo. Taken together, these results demonstrate that CBF is a potent apoptotic inducer with potential for further development as a novel and effective anticancer agent for a range of cancers, especially colon cancer.

Download Full-text

PIDDosome Expression and the Role of Caspase-2 Activation for Chemotherapy-Induced Apoptosis in RCCs

Analytical Cellular Pathology ◽

10.1155/2010/803824 ◽

2010 ◽

Vol 32 (1-2) ◽

pp. 29-42

Author(s):

Sebastian Heikaus ◽

Igor Pejin ◽

Helmut Erich Gabbert ◽

Uwe Ramp ◽

Csaba Mahotka

Keyword(s):

Tumour Progression ◽

Chemotherapy Resistance ◽

Clear Cell Type ◽

Alternatively Spliced ◽

Caspase 2 ◽

Induced Apoptosis ◽

Few Data

Background: The importance of caspase-2 activation for mediating apoptosis in cancer is not clear and seems to differ between different tumour types. Furthermore, only few data have been obtained concerning the expression of caspase-2, which can be alternatively spliced into caspase-2L and caspase-2S, and the other PIDDosome members PIDD and RAIDD in human tumours in vivo. We, therefore, investigated their expression in renal cell carcinomas (RCCs) of the clear cell type in vivo and analysed the role of caspase-2 in chemotherapy-induced apoptosis in RCCs in vitro.Methods: The analyses were performed by semiquantitative real-time PCR, Western Blot and Caspase-2 Assay.Results: Our in vivo results showed an overall decrease in proapoptotic caspase-2L expression during tumour progression due to an increase in the relative share of caspase-2S mRNA in total caspase-2 mRNA expression. Furthermore, an increase in the expression of PIDD and RAIDD could be observed. In contrast, antiapoptotic BCL-2 expression increased only during early tumour stages, whereas expression decreased in pT3 RCCs. In vitro, caspase-2 activation in RCC cell lines coincidenced with sensitivity of tumour cells towards Topotecan-induced apoptosis. However, inhibition of caspase-2 could not prevent Topotecan-induced apoptosis. Interestingly, Topotecan-resistance could be overcome by the apoptosis-sensitizing drug HA14-1.Conclusions: Our study confirms the concept of a shift towards a more antiapoptotic transcriptional context during tumour progression in RCCs. Furthermore, it shows that caspase-2 participates in chemotherapy-induced apoptosis in RCCs although it is not mandatory for it. Additionally, inhibition of antiapoptotic BCL-2 family members might provide a possible way to overcome chemotherapy resistance of RCCs.

Download Full-text

Zuo Jin Wan Reverses DDP Resistance in Gastric Cancer through ROCK/PTEN/PI3K Signaling Pathway

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2018/4278568 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Meng-Yao Sun ◽

Jian Sun ◽

Jie Tao ◽

Yu-Xia Yuan ◽

Zhen-Hua Ni ◽

...

Keyword(s):

Gastric Cancer ◽

Chemotherapy Resistance ◽

Underlying Mechanism ◽

Pi3k Signaling ◽

Gastric Cancer Cells ◽

Poor Overall Survival ◽

Mitochondrial Translocation ◽

Induced Apoptosis

Gastric cancer (GC) is the third leading cause of cancer-related death. Chemotherapy resistance remains the major reason for GC treatment failure and poor overall survival of patients. Our previous studies have proved that Zuo Jin Wan (ZJW), a traditional Chinese medicine (TCM) formula, could significantly enhance the sensitivity of cisplatin (DDP)-resistant gastric cancer cells to DDP by inducing apoptosis via mitochondrial translocation of cofilin-1. However, the underlying mechanism remains poorly understood. This study aimed to evaluate the effects of ROCK/PTEN/PI3K on ZJW-induced apoptosis in vitro and in vivo. We found that ZJW could significantly activate the ROCK/PTEN pathway, inhibit PI3K/Akt, and promote the apoptosis of SGC-7901/DDP cells. Inhibition of ROCK obviously attenuated ZJW-induced apoptosis as well as cofilin-1 mitochondrial translocation, while inhibition of PI3K had the opposite effects. In vivo, combination treatment of DDP and ZJW (2000 mg/kg) significantly reduced tumor growth compared with DDP alone. Moreover, the combined administration of ZJW and DDP increased the expression of cleaved ROCK and p-PTEN while it decreased p-PI3K and p-cofilin-1, which was consistent with our in vitro results. These findings indicated that ZJW could effectively inhibit DDP resistance in GC by regulating ROCK/PTEN/PI3K signaling and provide a promising treatment strategy for gastric cancer.

Download Full-text

Dual targeting of IGF-1R and ErbB3 as a potential therapeutic regimen for ovarian cancer

Scientific Reports ◽

10.1038/s41598-019-53322-y ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Adam J. Camblin ◽

Gege Tan ◽

Michael D. Curley ◽

Isabel Yannatos ◽

Sergio Iadevaia ◽

...

Keyword(s):

Ovarian Cancer ◽

Growth Factor ◽

Cancer Cell ◽

Ovarian Cancer Cell ◽

Chemotherapy Resistance ◽

Growth Factor Receptor ◽

Cell Surface Expression ◽

Chemotherapy Response

AbstractTherapeutically targeting receptor tyrosine kinases has proven to be paramount to overcoming chemotherapy resistance in several cancer indications, improving patient outcomes. Insulin-Like Growth Factor Receptor 1 (IGF-1R) and Epidermal Growth Factor Receptor 3 (ErbB3) have been implicated as two such drivers of resistance, however their simultaneous role in ovarian cancer chemotherapy resistance remains poorly elucidated. The aim of this work is to determine the effects of dual IGF-1R/ErbB3 inhibition on ovarian cancer cell signaling, growth, and in vivo efficacy. Assessment of in vitro chemotherapy response across a panel of ovarian cancer cell lines revealed that increased IGF-1R cell surface expression correlates with decreased sensitivity to chemotherapy, and that growth induced by IGF-1R and ErbB3 ligands is blocked by the tetravalent bispecific antibody targeting IGF-1R and ErbB3, istiratumab. In vitro chemotherapy treatment increased ovarian cancer cell line capacity to activate prosurvival PI3K signaling in response to ligand, which could be prevented with istiratumab treatment. Furthermore, in vivo efficacy of standard of care chemotherapies using a xenograft model of ovarian cancer was potentiated with istiratumab. Our results suggest a role for IGF-1R and ErbB3 in driving chemotherapy resistance of ovarian cancer.

Download Full-text

NFATC4 Promotes Quiescence and Chemotherapy Resistance in Ovarian Cancer

10.1101/825497 ◽

2019 ◽

Author(s):

Alexander J. Cole ◽

Mangala Iyengar ◽

Patrick O’Hayer ◽

Daniel Chan ◽

Greg Delgoffe ◽

...

Keyword(s):

Cell Cycle ◽

Ovarian Cancer ◽

Poor Prognosis ◽

Nuclear Translocation ◽

Marked Decrease ◽

Chemotherapy Resistance ◽

Chemotherapy Response ◽

Cycle Arrest

AbstractDevelopment of chemotherapy resistance is a major problem in ovarian cancer. One understudied mechanism of chemoresistance is the induction of quiescence, a reversible non-proliferative state. Unfortunately, little is known about regulators of quiescence. Here we identify the master transcription factor NFATC4 as a regulator of quiescence in ovarian cancer. NFATC4 is enriched in ovarian cancer stem-like cells (CSC) and correlates with decreased proliferation and poor prognosis. Treatment of cancer cells with cisplatin results in NFATC4 nuclear translocation and activation of NFATC4 pathway, while inhibition of the pathway increased chemotherapy response. Induction of NFATC4 activity results in a marked decrease in proliferation, G0 cell cycle arrest and chemotherapy resistance, both in vitro and in vivo. Finally, NFATC4 drives a quiescent phenotype in part via downregulation of MYC. Together these data identify that NFATC4 as a driver of quiescence and a potential new target to combat chemoresistance in ovarian cancer.

Download Full-text

Exosomal Vimentin from Adipocyte Progenitors Protects Fibroblasts against Osmotic Stress and Inhibits Apoptosis to Enhance Wound Healing

International Journal of Molecular Sciences ◽

10.3390/ijms22094678 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4678

Author(s):

Sepideh Parvanian ◽

Hualian Zha ◽

Dandan Su ◽

Lifang Xi ◽

Yaming Jiu ◽

...

Keyword(s):

Wound Healing ◽

Osmotic Stress ◽

Mechanical Stress ◽

Impaired Wound Healing ◽

In Vivo Experiments ◽

Adipocyte Progenitors ◽

Osmotic Balance ◽

Induced Apoptosis

Mechanical stress following injury regulates the quality and speed of wound healing. Improper mechanotransduction can lead to impaired wound healing and scar formation. Vimentin intermediate filaments control fibroblasts’ response to mechanical stress and lack of vimentin makes cells significantly vulnerable to environmental stress. We previously reported the involvement of exosomal vimentin in mediating wound healing. Here we performed in vitro and in vivo experiments to explore the effect of wide-type and vimentin knockout exosomes in accelerating wound healing under osmotic stress condition. Our results showed that osmotic stress increases the size and enhances the release of exosomes. Furthermore, our findings revealed that exosomal vimentin enhances wound healing by protecting fibroblasts against osmotic stress and inhibiting stress-induced apoptosis. These data suggest that exosomes could be considered either as a stress modifier to restore the osmotic balance or as a conveyer of stress to induce osmotic stress-driven conditions.

Download Full-text

iPLA2β Contributes to ER Stress-Induced Apoptosis during Myocardial Ischemia/Reperfusion Injury

Cells ◽

10.3390/cells10061446 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1446

Author(s):

Tingting Jin ◽

Jun Lin ◽

Yingchao Gong ◽

Xukun Bi ◽

Shasha Hu ◽

...

Keyword(s):

Cell Death ◽

Heart Disease ◽

Myocardial Ischemia ◽

Ischemic Heart Disease ◽

Er Stress ◽

Ischemia Reperfusion ◽

Myocardial Ischemia Reperfusion ◽

Induced Apoptosis

Both calcium-independent phospholipase A2 beta (iPLA2β) and endoplasmic reticulum (ER) stress regulate important pathophysiological processes including inflammation, calcium homeostasis and apoptosis. However, their roles in ischemic heart disease are poorly understood. Here, we show that the expression of iPLA2β is increased during myocardial ischemia/reperfusion (I/R) injury, concomitant with the induction of ER stress and the upregulation of cell death. We further show that the levels of iPLA2β in serum collected from acute myocardial infarction (AMI) patients and in samples collected from both in vivo and in vitro I/R injury models are significantly elevated. Further, iPLA2β knockout mice and siRNA mediated iPLA2β knockdown are employed to evaluate the ER stress and cell apoptosis during I/R injury. Additionally, cell surface protein biotinylation and immunofluorescence assays are used to trace and locate iPLA2β. Our data demonstrate the increase of iPLA2β augments ER stress and enhances cardiomyocyte apoptosis during I/R injury in vitro and in vivo. Inhibition of iPLA2β ameliorates ER stress and decreases cell death. Mechanistically, iPLA2β promotes ER stress and apoptosis by translocating to ER upon myocardial I/R injury. Together, our study suggests iPLA2β contributes to ER stress-induced apoptosis during myocardial I/R injury, which may serve as a potential therapeutic target against ischemic heart disease.

Download Full-text

Discovery of vanoxerine dihydrochloride as a CDK2/4/6 triple-inhibitor for the treatment of human hepatocellular carcinoma

Molecular Medicine ◽

10.1186/s10020-021-00269-4 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Ying Zhu ◽

Kun-Bin Ke ◽

Zhong-Kun Xia ◽

Hong-Jian Li ◽

Rong Su ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Cycle Progression ◽

G1 Arrest ◽

Huh7 Cells ◽

Synergistic Cytotoxicity ◽

Combination Study ◽

Experimental Approaches ◽

Induced Apoptosis

Abstract Background Cyclin-dependent kinases 2/4/6 (CDK2/4/6) play critical roles in cell cycle progression, and their deregulations are hallmarks of hepatocellular carcinoma (HCC). Methods We used the combination of computational and experimental approaches to discover a CDK2/4/6 triple-inhibitor from FDA approved small-molecule drugs for the treatment of HCC. Results We identified vanoxerine dihydrochloride as a new CDK2/4/6 inhibitor, and a strong cytotoxicdrugin human HCC QGY7703 and Huh7 cells (IC50: 3.79 μM for QGY7703and 4.04 μM for Huh7 cells). In QGY7703 and Huh7 cells, vanoxerine dihydrochloride treatment caused G1-arrest, induced apoptosis, and reduced the expressions of CDK2/4/6, cyclin D/E, retinoblastoma protein (Rb), as well as the phosphorylation of CDK2/4/6 and Rb. Drug combination study indicated that vanoxerine dihydrochloride and 5-Fu produced synergistic cytotoxicity in vitro in Huh7 cells. Finally, in vivo study in BALB/C nude mice subcutaneously xenografted with Huh7 cells, vanoxerine dihydrochloride (40 mg/kg, i.p.) injection for 21 days produced significant anti-tumor activity (p < 0.05), which was comparable to that achieved by 5-Fu (10 mg/kg, i.p.), with the combination treatment resulted in synergistic effect. Immunohistochemistry staining of the tumor tissues also revealed significantly reduced expressions of Rb and CDK2/4/6in vanoxerinedihydrochloride treatment group. Conclusions The present study isthe first report identifying a new CDK2/4/6 triple inhibitor vanoxerine dihydrochloride, and demonstrated that this drug represents a novel therapeutic strategy for HCC treatment.

Download Full-text

STEM-29. THE HISTONE VARIANT macroH2A2 ORCHESTRATES AN ACTIONABLE CHROMATIN PROGRAM OF STEMNESS IN GLIOBLASTOMA

Neuro-Oncology ◽

10.1093/neuonc/noaa215.846 ◽

2020 ◽

Vol 22 (Supplement_2) ◽

pp. ii202-ii202

Author(s):

Ana Nikolic ◽

Anna Bobyn ◽

Katrina Ellestad ◽

Xueqing Lun ◽

Michael Johnston ◽

...

Keyword(s):

Chromatin Accessibility ◽

Histone Variant ◽

Clinical Settings ◽

Glioblastoma Cells ◽

Self Renewal ◽

Viral Mimicry ◽

Experimental Findings ◽

Preclinical Work

Abstract Glioblastoma cells with the crucial stemness property of self-renewal constitute therapy-resistant reservoirs that seed tumor relapse. Effective targeting of these cells in clinical settings has been hampered by their relative quiescence, which invalidates the cell replication bias of most current treatments. Furthermore, although their dependence on specific chromatin and transcriptional states for the maintenance of stemness programs has been proposed as a vulnerability, these nuclear programs have been challenging to target pharmaceutically. Therefore the identification of targetable chromatin paradigms regulating self-renewal would represent a significant advancement for this incurable malignancy. Here we report a new role for the histone variant macroH2A2 in modulating a targetable epigenetic network of stemness in glioblastoma. By integrating transcriptomic, bulk and single-cell epigenomic datasets we generated from patient-derived models and surgical specimens, we show that macroH2A2 represses a transcriptional network of stemness through direct regulation of chromatin accessibility at enhancer elements. Functional assays in vitro and in vivo further showcase that macroH2A2 antagonizes self-renewal and stemness in glioblastoma preclinical models. In agreement with our experimental findings, high expression of macroH2A2 is a positive prognostic factor in clinical glioblastoma cohorts. Reasoning that increasing macroH2A2 levels could be an effective strategy to repress stemness programs and ameliorate patient outcome, we embarked on a screen to identify compounds that could elevate macroH2A2 levels. We report that an inhibitor of the chromatin remodeler Menin increases macroH2A2 levels, which in turn repress self-renewal. Additionally, we provide evidence that Menin inhibition induces viral mimicry programs and the demise of glioblastoma cells. Menin inhibition is being tested in clinical trials for blood malignancies (NCT04067336). Our preclinical work therefore reveals a novel and central role for macroH2A2 in an epigenetic network of stemness and suggests new clinical approaches for glioblastoma.

Download Full-text