SDHB-mediated regulation of the diverse hallmarks of CRC cells through AMPK modulation. SDHB was overexpressed or knocked down in CRC HT-29 cells. A total of 0.1 mM AICAR (an AMPK activator) and 20 µm/l Compound C (an AMPK inhibitor) were added to activate and inhibit the activity of AMPK, respectively. Cell viability and apoptosis were evaluated using (A) MTT and (B) flow cytometry analysis, respectively. (C) Western blot analysis was performed to detect p21/WAF1 and caspase-3 expression. Cell migration and invasion were evaluated using (D) wound healing (magnification, ×200; Con indicated the 0 h time point) and (E) invasion (magnification, ×400) assays. *P<0.05, **P<0.01, #P<0.05 and ##P<0.01 vs. the respective control group. SDHB, succinate dehydrogenase-B; CRC, colorectal cancer; AMPK, adenosine monophosphate activated protein kinase; AICAR, 5-aminoimidazole-4-carboxamide ribonucleotide; OV, SDHB expression vector; Act, AMPK activator; shR, shRNA targeting SDHB; Inh, AMPK inhibitor; FITC, Annexin-V-fluorescein isothiocyanate.