基于缺氧诱导因子-1α/血管内皮生长因子信号通路探讨肿瘤藤(星毛冠盖藤)治疗人肝癌细胞移植瘤小鼠的作用机制OA

Objective To investigate the therapeutic effects of Pileostegia tomentella(PT)on HepG2 xenograft tumors in mice and explore its anti-tumor mechanism.Methods A HepG2 xenograft tumor model was established by subcutaneously inoculating HepG2 cells into the left shoulder/back region of Balb/c mice.Thirty-six mice were randomly divided into six groups(n=6 per group):model group,negative control group(normal saline),positive control group(sorafenib,0.03 g/kg),and low-,medium-,and high-dose PT groups(3.4 g/kg,6.8 g/kg,13.6 g/kg,respectively).Treatments were administered daily via gastric gavage for 21 days.Hematoxylin-eosin(HE)staining was used to observe histopathological changes in tumor tissues.The method of TUNEL assay was used to detecte apoptosis,immunohistochemistry(IHC)was used to evaluate CASP9,CD31,Ki67,and MCM protein expression,immunofluorescence(IF)was used to assesse VEGFA fluorescence,and RT-PCR and Western blot(WB)was used to analyzed HIF-1α,VEGFA,and CD31 mRNA and protein levels.Results HE staining revealed tightly arranged,irregularly nucleated cells with increased pathological mitosis in the model and negative control groups.In contrast,the positive control and the PT groups exhibited disorganized cell arrangement,extensive apoptosis,and necrosis.TUNEL results showed significantly increased apoptosis in the positive control and the PT groups compared with the model and the negative control groups(P＜0.05).IHC demonstrated upregulated CASP9 expression and downregulated CD31,Ki67,and MCM expression in the treated groups(P＜0.05),with the medium-dose PT group showing the most pronounced CASP9 upregulation(P＜0.05).IF revealed reduced VEGFA fluorescence in treated groups(P＜0.05).The results of RT-PCR and WB confirmed down-regulated HIF-1α,VEGFA,and CD31 mRNA and protein levels in the treatment groups(P＜0.05),with optimal efficacy in the medium-dose PT group(P＜0.05).Conclusion PT may inhibit tumor cell proliferation and angiogenesis by regulating the HIF-1α/VEGFA pathway,thereby promoting apoptosis and necrosis in HepG2 xenograft tumors.