不同pH值条件下多柔比星对胃癌BGC823细胞增殖、凋亡的影响及机制研究

目的 探讨在不同pH值培养条件下多柔比星(doxorubicin，ADM)对胃癌BGC823细胞增殖、凋亡能力的影响及初步机制研究。 方法 采用细胞活性测定试剂盒(CCK-8)法检测不同pH值培养条件下多柔比星对胃癌细胞BGC823增殖活性的影响；应用Annexin V/PI双染法，在荧光显微镜下观察凋亡细胞的形态，用流式细胞仪检测胃癌细胞凋亡率；采用qRT-PCR法检测p-AKT、BCL-2和NF-κB基因在胃癌细胞中的表达。 结果 ①ADM对胃癌BGC823细胞的半数抑制浓度(IC₅₀)值为5.277 μg/mL，考虑化疗药物毒性及后续实验，ADM剂量选择该细胞株IC₅₀值1/4的浓度(即1.319 μg/mL)用于进行后续实验；②随着pH值升高，ADM对BGC823细胞增殖活性的抑制作用增强，当pH达到7.4时，抑制增殖作用最明显；③随着pH值升高，ADM对BGC823细胞凋亡水平明显增加，当pH达到7.4时，促凋亡作用最明显，再提高pH浓度，促凋亡作用能力不明显；④不同pH(pH 6.8～7.6)环境下，ADM处理后，随着pH升高，BCL-2、NF-κB和p-AKT基因表达水平明显降低。 结论 升高细胞外pH值能明显提高ADM对BGC823细胞抑制细胞增殖、促进细胞凋亡的能力，这种与pH值相关的ADM抗肿瘤效果可能是通过抑制AKT的磷酸化，阻止NF-κB、Bcl-2等抗凋亡基因表达来实现的。 

Effects of doxorubicin on proliferation and apoptosis of gastric cancer BGC823 cells under different pH conditions and preliminary mechanism

Objective To investigate the effects of doxorubicin on the proliferation and apoptosis of gastric cancer BGC823 cells under different pH conditions and the preliminary mechanism. Methods The effect of doxorubicin (ADM) cultured under different pH conditions on the proliferation of gastric cancer cell line BGC823 was detected by cell viability assay kit (CCK-8); Morphology of apoptotic cells were observed under fluorescence microscope; The apoptosis of BGC823 was assessed with Annexin V-PI; The expression of p-AKT, BCL-2 and NF-κB genes and proteins in gastric cancer cells were detected by qRT-PCR. Results ①The half-inhibitory concentration (IC₅₀) of ADM on gastric cancer BGC823 cells was 5.277 μg/mL. Considering the toxicity of chemotherapy drugs and subsequent experiments, the ADM dose was selected to be 1/4 times the IC₅₀ value of the cell line (1.319 μg/mL) for subsequent experiments; ②With the increase of pH, the inhibitory effect of ADM on the proliferation of BGC823 cells was enhanced. When the pH reached 7.4, the inhibition of proliferation was the most obvious. ③With the increase of pH, the apoptosis of BGC823 cells increased significantly with ADM. When the pH reached 7.4, the pro-apoptotic effect was the most obvious, and the pH concentration was further increased, and the ability to promote apoptosis was not obvious; ④Under different pH (pH 6.8-7.6) environment, the expression levels of BCL-2, NF-κB and p-AKT genes decreased significantly with the increase of pH after ADM treatment. Conclusion Increasing the extracellular pH can significantly increase the ability of ADM to inhibit cell proliferation and promote apoptosis in BGC823 cells. The anti-tumor effect of this pH-related ADM may be achieved by inhibiting the phosphorylation of AKT and preventing the expression of anti-apoptotic proteins such as NF-κB and Bcl-2.