DCBLD1经糖代谢重编程及ROS清除降低口腔鳞状细胞癌顺铂敏感性且沉默其可逆转耐药OA

Objective Oral squamous cell carcinoma(OSCC)is highly malignant and associated with poor prognosis.Cisplatin serves as the first‑line chemotherapeutic cornerstone for OSCC,however,the frequent occurrence of drug resistance substantially compromises its clinical benefit.This study aims to screen and validate key regulatory genes underlying baseline cisplatin sensitivity in OSCC,and to clarify the molecular pathways through which these genes reduce cisplatin sensitivity via glycolytic reprogramming and redox homeostasis imbalance,thereby providing potential molecular targets and experimental theoretical support for enhancing OSCC chemosensitivity.Methods Three OSCC expression profiling datasets(GSE30784,GSE31056,and GSE102787)were downloaded from the GEO database.Differentially expressed genes(DEGs)screening,weighted gene co‑expression network analysis(WGCNA),and Venn intersection analysis were performed using R language.Furthermore,survival prognosis was evaluated using the TCGA‑HNSC cohort,and candidate genes were prioritized according to statistical significance and clinical relevance to identify core candidate genes associated with reduced baseline cisplatin sensitivity in OSCC.The core gene DCBLD1,a transmembrane protein containing discoidin,CUB and LCCL domains,was identified as the target molecule through joint screening for multiple datasets.Western blotting was used to detect DCBLD1 expression in multiple OSCC cell lines and HOK cells.Small interfering RNA(siRNA)transfection was employed to construct SCC‑15 cells with DCBLD1 knockdown.The Warburg effect was assessed by measuring intracellular glucose uptake and lactate production.Chemosensitivity was evaluated by determining the half‑maximal inhibitory concentration(IC ₅ ₀)of cisplatin via CCK‑8 assay.Exogenous supplementation of lactate and pyruvate was performed to examine their effects on baseline cisplatin sensitivity in cells.The effects of exogenous lactate and pyruvate supplementation on baseline cisplatin sensitivity were examined.The expression of glucose-6-phosphate dehydrogenase(G6PD),the rate-limiting enzyme of the pentose phosphate pathway,and the levels of reduced nicotinamide adenine dinucleotide phosphate(NADPH),glutathione(GSH)and reactive oxygen species(ROS)were detected to reflect cellular redox status.Rescue experiments with the ROS scavenger N-acetyl-L-cysteine(NAC)were performed to clarify the mediating role of ROS in DCBLD1-regulated basal cisplatin sensitivity.Results Integrated bioinformatics analysis identified DCBLD1 and WD repeat domain 66(WDR66)as 2 core genes that reduce baseline cisplatin sensitivity in OSCC.Survival analysis revealed that high DCBLD1 expression was significantly associated with poor prognosis(HR=1.3,PHR=0.048),whereas WDR66 showed no significant prognostic value(P=0.42).Therefore,DCBLD1 was selected for subsequent investigation.DCBLD1 was significantly highly expressed in OSCC cells(P<0.05).Knockdown of DCBLD1 significantly suppressed aerobic glycolysis in SCC‑15 cells,reduced glucose consumption and lactate production(P<0.05),decreased the IC50 of cisplatin,and effectively enhanced baseline cisplatin sensitivity.Exogenous lactate and pyruvate intervention failed to restore the low‑sensitivity phenotype.DCBLD1 knockdown downregulated G6PD expression(P<0.05),inhibited activation of the pentose phosphate pathway(PPP),reduced intracellular NADPH and GSH antioxidant reserves(P<0.05),and induced ROS accumulation.NAC‑mediated ROS clearance restored the low cisplatin sensitivity and reversed the chemosensitization effect induced by DCBLD1 silencing.Conclusion DCBLD1 triggers glycolytic reprogramming by simultaneously activating aerobic glycolysis and the PPP,and attenuates the cisplatin-induced cytotoxicity by enhancing antioxidant capacity and scavenging via the PPP.DCBLD1 thus represents a potential therapeutic target for reducing baseline cisplatin sensitivity in OSCC.