State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China.
J Pharm Pharmacol. 2022 Apr 20;74(4):596-604. doi: 10.1093/jpp/rgab073.
The combination of gemcitabine (Gem) and hypericin (HY) enhances the apoptosis of Capan-2 cells, providing a promising option for the treatment of pancreatic cancer. Our study further explored the cytotoxic mechanism of HY combined with chemotherapy drugs on pancreatic cancer.
The proliferation rate of the cells assayed with the MTT method. The ROS (reactive oxygen species) levels of each treatment were evaluated by DCFH-DA oxidisation methods. The activity of glutathione reductase and the levels of reduced glutathione (GSH) and oxidised glutathione (GSSG) were assessed using assay kits. The expression levels of apoptosis-related proteins were analysed by western blotting.
The activity of glucose-6-phosphate dehydrogenase (G6PDH), a key enzyme of the pentose phosphate pathway, significantly decreased in Gem + HY groups, however, the ROS level enhanced accompanying with GSH depleting, mitochondrial membrane depolarisation and cytochrome C release. Gem + HY inhibits the expression of Bcl-2 but stimulates Bax level, triggering caspase activation and PARP cleavage and thus promoted apoptosis of Capan-2 cells.
We demonstrated that Gem combined HY-PDT could inhibit the proliferation of Capan-2 cells and induce cell apoptosis. HY-PDT combined with Gem had a great potential on pancreatic cancer treatment clinically.
吉西他滨（Gem）和金丝桃素（HY）的联合使用增强了 Capan-2 细胞的凋亡，为胰腺癌的治疗提供了一种有前途的选择。本研究进一步探讨了 HY 联合化疗药物对胰腺癌的细胞毒性机制。
采用 MTT 法检测细胞增殖率。采用 DCFH-DA 氧化法评估各处理组的 ROS（活性氧）水平。使用试剂盒评估谷胱甘肽还原酶的活性以及还原型谷胱甘肽（GSH）和氧化型谷胱甘肽（GSSG）的水平。通过 Western 印迹分析凋亡相关蛋白的表达水平。
戊糖磷酸途径的关键酶葡萄糖-6-磷酸脱氢酶（G6PDH）的活性在 Gem + HY 组中显著降低，然而，ROS 水平升高伴随着 GSH 耗竭、线粒体膜去极化和细胞色素 C 释放。Gem + HY 抑制 Bcl-2 的表达，但刺激 Bax 水平，引发半胱天冬酶的激活和 PARP 的切割，从而促进 Capan-2 细胞的凋亡。
我们证明 Gem 联合 HY-PDT 可抑制 Capan-2 细胞的增殖并诱导细胞凋亡。HY-PDT 联合 Gem 在临床上对胰腺癌的治疗具有很大的潜力。
