Objective: To observe the anticancer effects of the granular preparation of Tenglong Buzhong decoction (,TBD), i.e Tenglong Buzhong granules (, TBG), in human SW620 colon cancer.
Methods: BALB/c nude mice were subcutaneously transplanted with SW620 cells, and treated with TBG (2.56 g/kg, once per day) and/or 5-Fu (104 mg/kg, once per week) for 21 d. Apoptosis, Caspase activities and cellular senescence were measured by commercial kits. The protein expression and phosphorylation were detected by Western blot or immunohistochemistry.
Results: TBG and 5-Fu inhibited tumor growth. The tumor inhibition rate of the TBG, 5-Fu, and TBG+5-Fu groups was 42.25%, 51.58%, and 76.08%, respectively. Combination of TBG and 5-Fu showed synergetic anti-cancer effects. TBG and 5-Fu induced apoptosis, activated caspase-3, -8, and -9, increased SMAC expression, inhibited XIAP expression. TBG induced cellular senescence, upregulated cyclin-dependent kinase inhibitor 1a (CDKN1a) and cyclin-dependent kinase inhibitor 2a (CDKN2a) expression, and inhibited phosphorylation of retinoblastoma-associated protein (RB) and expression of cyclin E1 (CCNE1) and cyclin-dependent kinases (CDK) 2. TBG also inhibited angiogenesis accompanied by downregulation of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α (HIF-1α).
Conclusions: TBG inhibits SW620 colon cancer growth, induces apoptosis SMAC-XIAP-Caspases signaling, induces cellular senescence through CDKN1a/CDKN2a-RB-E2F signaling, inhibits angiogenesis by down-regulation of HIF-1α and VEGF, and enhances the effects of 5-Fu.
Keywords: Tenglong Buzhong granules; angiogenesis; apoptosis; cellular senescence; colonic neoplasms; signal transduction.