Promoting GSDME expression through DNA demethylation to increase chemosensitivity of breast cancer MCF-7 / Taxol cells

Abstract

Objective Breast cancer is the most common and high-incidence cancer in women. It is mainly treated by surgery combined with chemoradiation. The main challenge in treating breast cancer patients is developing resistance to chemotherapeutics, so it is urgent to find potential strategies that can improve the chemotherapy effect of patients. In this study, we aimed to explore the role of GSDME methylation in the sensitivity of chemotherapy for breast cancer. Methods Here, we identified breast cancer MCF-7 / Taxol cells models using quantitative real-time PCR (qRT-PCR), Western blotting (WB), and cell counting kit-8 (CCK-8) analyses. Epigenetic changes in it were detected by Methylated DNA immunoprecipitation-sequencing and methylation-specific PCR. The expression level of GSDME in breast cancer cells was observed by qPCR and WB analyses. CCK-8 and colony formation assay were used to detect cell proliferation. Finally, pyroptosis was detected by LDH assay, flow cytometry, and WB analyses. Results Our results indicate that ABCB1 mRNA and p-GP expression are significantly increased in breast cancer MCF-7 / Taxol cells. GSDME enhancer methylation was found in drug-resistant cells and was associated with the down-regulation of GSDME expression. After treatment with decitabine (5-Aza-2’-deoxycytidine), the demethylation of GSDME induced the occurrence of pyroptosis and thereby inhibited the proliferation of MCF-7 / Taxol cells. We found that the upregulation of GSDME enhances the chemosensitivity of MCF-7 / Taxol cells to paclitaxel by inducing pyroptosis. Conclusion Taken together, we identified decitabine increases GSDME expression through DNA demethylation and induces pyroptosis, thus increasing the chemosensitivity of MCF-7 / Taxol cells to Taxol. Use of decitabine / GSDME / pyroptosis-based treatment strategies may be a new way to overcome the resistance of breast cancer to paclitaxel chemotherapy.

GSDME has prognostic and immunotherapeutic significance in residual hepatocellular carcinoma after insufficient radiofrequency ablation

“…Hypermethylation existed in the promoter of GSDME, and decitabine (DAC) could increase GSDME expression via reducing methylation by inhibiting DNA methyltransferase (DNMT) [ 9 , 30 ]. HCCLM3 and HepG2 were treated with DAC, and MTT assay showed that DAC wasn't cytotoxic to HCC cells (Supplementary Figure 1A).…”

Pyroptosis and inflammasomes in cancer and inflammation

“…Cisplatin enhances complete response rates in patients with triple‐negative breast cancer patients by activating the lncRNA MEG3/NLRP3/caspase 1/GSDMD pyroptosis pathway 128 . Decitabine triggers GSDME expression by DNA demethylation, boosting pyroptosis and the chemosensitivity of MCF‐7/Taxol cells to Taxol 129 . TNFα‐induced apoptosis is converted to pyroptosis by antibiotic chemotherapy drugs (daunorubicin, DOX, epirubicin, and actinomycin D) that activate PD‐L1.…”

“… 128 Decitabine triggers GSDME expression by DNA demethylation, boosting pyroptosis and the chemosensitivity of MCF‐7/Taxol cells to Taxol. 129 TNFα‐induced apoptosis is converted to pyroptosis by antibiotic chemotherapy drugs (daunorubicin, DOX, epirubicin, and actinomycin D) that activate PD‐L1. The interaction between p‐Stat3 and PD‐L1 during hypoxia facilitates its nuclear translocation, increasing GSDMC expression and triggering the GSDMC/caspase 8 pyroptosis pathway.…”