高良姜素抑制胃癌MGC803细胞NF-κB通路促进自噬

Galangin enhances autophagy by inhibiting NF-κB pathway in gastric cancer MGC-803 cells

探究高良姜素对胃癌细胞MGC803能量代谢和自噬的影响及其可能的分子机制。细胞增殖-毒性检测试剂盒(cell counting kit-8,CCK-8)检测不同浓度高良姜素干预MGC803细胞48 h对细胞活力的影响;蛋白免疫印迹(Western blot)法检测高良姜素对MGC803细胞自噬、核因子κB(nuclear factor-κB,NF-κB)通路、能量代谢相关蛋白的表达;实时荧光定量核酸扩增检测(Real-time quantitative PCR,qPCR)法检测高良姜素对MGC803细胞能量代谢相关蛋白mRNA表达的影响;自噬小体检测试剂盒检测高良姜素对MGC803细胞自噬体的作用;透射电子显微镜观察高良姜素对MGC803细胞自噬体和溶酶体的影响。裸鼠皮下注射MGC803细胞制备胃癌移植瘤模型,随机分组后,模型组灌胃给予0.5%羧甲基纤维素钠,高良姜素组每天灌胃给予高良姜素(120 mg·kg^(-1)),阳性对照组腹腔注射5-氟尿嘧啶(5-fluorouracil, 5-FU)(50 mg·kg^(-1),1周2次),每3 d相同时间同一人用游标卡尺精确测量肿瘤大小及裸鼠体质量,给药21 d后处死动物,剥离肿瘤并称重,计算抑瘤率。结果显示,与对照组相比,高良姜素能够抑制MGC803细胞的活力;高良姜素可上调MGC803细胞Ⅱ型微管相关蛋白1轻链3B(microtuble-associated protein 1 light chain 3B,LC3B)的蛋白表达,同时可抑制NF-κB通路相关蛋白的磷酸化水平;高良姜素促进MGC803细胞中自噬小体的形成;高良姜素对MGC803细胞能量代谢相关蛋白的表达水平无明显影响;120 mg·kg^(-1)高良姜素显著抑制荷瘤裸鼠胃癌肿瘤质量和体积的增长,并能够显著上调LC3BⅡ蛋白表达,同时可抑制NF-κB通路相关蛋白的磷酸化水平。结果表明,高良姜素体内外均能够抑制胃癌细胞MGC803的生长,其作用机制可能与其抑制NF-κB通路、促进自噬有关。

This study aimed to explore the effects of galangin on energy metabolism and autophagy in gastric cancer MGC803 cells and the underlying mechanism. Cell counting kit-8(CCK-8) was used to detect the effects of galangin at different concentrations on via-bility of MGC803 cells after 48 h intervention. Western blot was carried out to measure the effects of galangin on expression of proteins related to autophagy, nuclear factor-κB(NF-κB) pathway and energy metabolism, followed by the determination of its effects on mRNA expression of energy metabolism-related proteins by Real-time quantitative PCR(qPCR). The impact of galangin on autophagy was explored using AutophagyGreen dye reagent, with autophagosomes and lysosomes observed under the transmission electron microscope(TEM). Nude mice transplanted with gastric cancer MGC803 cells via subcutaneous injection were randomly divided into the following three groups: control(0.5% sodium carboxymethyl cellulose, once a day), 5-fluorouracil(5-FU, 50 mg·kg^(-1), twice a week), and galangin(120 mg·kg^(-1), once a day) groups. The body weight and tumor volume were measured once every three days with a vernier caliper at the same time point by the same person. After 21-d treatment, the tumor tissue was isolated and weighed for the calculation of the tumor-suppressing rate. The comparison with the control group revealed that galangin inhibited the viability of MGC803 cells, up-regulated the protein expression of microtuble-associated protein 1 light chain 3 B(LC3 B) Ⅱ, inhibited the phosphorylation of NF-κB pathway-related proteins, and promoted the formation of autophagosomes in MGC803 cells. However, it did not obviously affect the expression of energy metabolism-related proteins. Furthermore, galangin at 120 mg·kg^(-1) significantly reduced the tumor weight and volume in mice, enhanced LC3 BⅡ protein expression, and inhibited the phosphorylation of NF-κB pathway-related proteins. All these have suggested that galangin inhibited the growth of gastric cancer MGC803 cells both in vivo and in vitro, possibly by inhibiting the NF-κB pathway and enhancing autophagy.