【摘要】 目的 探讨藤黄酸（gambogic acid, GA）对胰腺癌细胞吉西他滨（gemcitabine, GEM）化疗敏感性的调控作用及其潜在分子机制。方法 采用GEM浓度递增法构建胰腺癌耐药细胞株，评估GA对耐药细胞的增殖抑制效应。通过实时荧光定量逆转录PCR（RT-qPCR）和Western Blot检测GA对富含亮氨酸重复序列蛋白8A（leucine-rich repeat-containing protein 8A,LRRC8A）表达的影响。进一步构建LRRC8A敲低的胰腺癌类器官（patient-derived organoids, PDOs）模型，利用Cell Titer-Glo发光法测定敲低LRRC8A后GEM的半数抑制浓度(IC₅₀),探究GA联合GEM对细胞活力的协同作用。运用网络药理学与分子对接技术预测GA降低耐药的潜在靶点，并通过Western Blot实验进行验证。建立胰腺癌异种移植小鼠模型，观察GA治疗对肿瘤体积的影响，并通过免疫组化检测LRRC8A在治疗前后表达水平的变化。结果 GA显著抑制胰腺癌耐药细胞及PDOs的生长，且通过调节LRRC8A/STAT3信号通路有效提高细胞对GEM的敏感性。体内实验进一步证实，GA干预可显著降低LRRC8A的表达水平，并抑制胰腺癌的生长。结论 GA可通过抑制LRRC8A的表达，增强胰腺癌细胞对GEM的化疗敏感性。更多还原

【Abstract】 Objective This study aimed to examine how gambogic acid(GA) modulates pancreatic cancer cell sensitivity to gemcitabine(GEM) chemotherapy, and to elucidate the underlying molecular mechanisms involved. Methods GEM-resistant pancreatic cancer cell lines were established using a concentration-escalation method, and GA suppressive activity against drug-resistant cell proliferation was assessed. The influence of GA on leucine-rich repeat-containing protein 8A(LRRC8A) expression was examined with quantitative reverse transcription PCR(RT-qPCR)and Western Blot analyses. A LRRC8A-knockdown patient-derived organoids(PDOs) model was constructed, and the half-maximal inhibitory concentration of GEM post-knockdown was measured using the Cell Titer-Glo luminescence assay to explore the synergistic effect of GA and GEM on cell viability. Potential targets through which GA mitigates chemoresistance were forecasted using network-based pharmacological approaches and molecular docking simulations, with subsequent Western Blot analyses providing experimental verification. Murine xenograft models bearing human pancreatic carcinoma were established to monitor the therapeutic impact of GA on neoplastic growth. Comparative immunohistochemical analysis of LRRC8A expression levels was conducted pre-and post-intervention. Results GA significantly inhibited the growth of GEM-resistant pancreatic cancer cells and patient-derived organoids and effectively enhanced cellular sensitivity to GEM by regulating LRRC8A/STAT3 signaling. In vivo experiments further confirmed that GA intervention significantly reduced LRRC8A expression and suppressed pancreatic cancer progression. Conclusions GA-mediated downregulation of LRRC8A conferred GEM sensitivity in pancreatic cancer cells.更多还原