Abstract：
We aimed to explore the role of regulating Smac expression levels in the occurrence and development of colon cancer through in vitro and in vivo experiments. Colon cancer cells HT-29 were cultured and transfected into different groups. qRT-PCR was used to detect the expression level of Smac in cells; Flow cytometry was used to detect the apoptotic ability of each group of cells; Western blot was used to detect the protein expression of Smac and apoptosis-related factors Survivin and Caspase-3; The nude mouse tumorigenesis experiment was conducted to detect the regulatory effect of regulating Smac expression levels on the growth of colon cancer transplanted tumors in vivo. In comparison to the FHC group, the HT-29 group exhibited a decrease in Smac expression. The si-Smac group, when compared with the si-NC group, showed significant reductions in Smac mRNA and protein levels, weaker cell apoptosis, increased Survivin, and decreased Caspase-3 expression. Contrarily, the oe-Smac group, against the oe-NC group, displayed increased Smac mRNA and protein levels, enhanced apoptosis, reduced Survivin, and elevated Caspase-3 expression. In nude mice tumor transplantation experiments, the LV-sh-Smac group, as opposed to the LV-sh-NC group, had tumors with greater volume and weight, reduced Smac and Caspase-3, and increased Survivin expression. In contrast, the LV-oe-Smac group, compared with the LV-oe-NC group, showed tumors with decreased volume and mass, increased expressions of Smac and Caspase-3, and decreased Survivin. Smac is lowly expressed in colon cancer. Upregulation of Smac expression can inhibit the occurrence and development of colon cancer, possibly by inhibiting Survivin expression and promoting Caspase-3 expression, thereby enhancing the pro-apoptotic function.
摘要：
通过体内外实验,探讨Smac表达调控在结肠癌发生发展中的作用。将结肠癌细胞HT-29培养并转染到不同的组中。qRT-PCR检测细胞中Smac的表达水平;流式细胞术检测各组细胞的凋亡能力;Westernblot检测Smac及凋亡相关因子Survivin、Caspase-3的蛋白表达;裸鼠成瘤实验检测调节Smac表达水平对结肠癌移植瘤体内生长的调控作用。与FHC组相比，HT-29组Smac表达降低。si-Smac集团,与si-NC组相比，显示SmacmRNA和蛋白质水平显着降低，细胞凋亡较弱，增加Survivin,并降低Caspase-3的表达。相反，oe-Smac集团,反对oe-NC小组，显示增加的SmacmRNA和蛋白质水平，细胞凋亡增强，减少幸存者，和升高的Caspase-3表达。在裸鼠肿瘤移植实验中，LV-sh-Smac组,与LV-sh-NC组相反，肿瘤体积和重量更大，降低Smac和Caspase-3，增加Survivin表达。相比之下,LV-oe-Smac组,与LV-OE-NC组相比，显示肿瘤体积和质量减少，Smac和Caspase-3的表达增加，Survivin降低。Smac在结肠癌中低表达。上调Smac表达可抑制结肠癌的发生发展,可能通过抑制Survivin表达和促进Caspase-3表达，从而增强促凋亡功能。
