METHODS: Using a retroviral method, we first ectopically expressed DOC2B in SiHa cells, which do not normally express DOC2B.
RESULTS: We observed that ectopically expressed DOC2B significantly altered the global metabolite profile of EVs. Metabolomics identified significant enrichment of palmitoylcarnitine (PC) in EVs upon ectopic expression of DOC2B. We identified that SiHa and HeLa cells exhibited greater cytotoxicity to PC than gingival fibroblast, HaCaT, Cal27, and MCF7. PC treatment reduced the growth, proliferation, and migration of SiHa and HeLa cells, via increasing apoptosis and decreasing S-Phase cells. PC treatment resulted in morphological alterations, decreased length and number of filopodia, and expression of proteins related to cell cycle progression, proliferation, and the epithelial-to-mesenchymal transition. Further, PC treatment caused mitochondrial morphological changes, increased mitochondrial membrane potential, and decreased mtDNA content. The decreased GSH activity, glucose consumption rate, and lactate production upon PC treatment suggest that PC can induce metabolic reprogramming in CC cells. Increased oxidative stress, calcium overload, lipid droplet accumulation, mitochondrial lipotoxicity, and mitophagy suggest that PC can cause mitochondrial dysfunction. N-acetyl cysteine (NAC) treatment reversed the cytotoxic effect of PC, via decreasing lipid peroxidation rate and increasing GSH activity. PC treatment enhanced the cytotoxic effect of cisplatin in CC.
CONCLUSION: DOC2B restoration or the use of PC may be employed as a novel therapeutic approach for CC.
METHODS: • Analyzed gynecological cancer datasets from The Cancer Genome Atlas (TCGA) and Cancer Cell Line Encyclopedia (CCLE) databases to evaluate PDK3 expression. • Performed KEGG pathway enrichment analysis to identify biological pathways associated with PDK3. • Kaplan-Meier survival analysis revealed cancer-type-specific associations between PDK3 expression and overall survival in breast, cervical, and endometrial cancer. • Assessed the impact of PDK3 expression on immune cell proportion and distribution in breast, cervical, and endometrial cancers. • Performed PDK3 knockdown experiments in SiHa cells to evaluate its effects on cell proliferation and growth.
RESULTS: • PDK3 was significantly upregulated in breast, cervical, and endometrial cancer samples compared with corresponding normal tissues. • KEGG pathway analysis showed significant enrichment of pathways related to cancer, viral carcinogenesis, and human papillomavirus (HPV) infection. • Elevated PDK3 expression was associated with poorer overall survival in breast and cervical cancer patients. • PDK3 upregulation influenced the proportion and distribution of immune cells in breast, cervical, and endometrial cancers. • Experimental knockdown of PDK3 significantly inhibited the proliferation and growth of SiHa cells.
CONCLUSION: PDK3 appears to function as a potential oncogene in gynecological cancers. Its overexpression is associated with tumor progression, altered immune cell infiltration, and reduced survival in certain gynecological cancers. Therefore, PDK3 may serve as a promising prognostic biomarker and therapeutic target in gynecological malignancies.