Aim:The aim of the present study was to determine the effect of 5-aminoimidazole-4-carboxamide-ribonucleoside (AICAR) on proliferation,cell cycle,and apoptosisin the human epithelial cervical cancer cell line CaSki cells.Methods:Cell countand 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay were usedto determine cell proliferation and viability.Hoechst 33258 staining was con-ducted to distinguish the apoptotic cells.Cell cycle and Annexin-V/propidiumiodide staining were analyzed by fluorescence-activated cell sorting (FACS).AWestern blot assay was used to evaluate the expression of AKT (also known asprotein kinase B),mammalian target of rapamycin (mTOR),p53,and extracellularsignal-regulated kinase (ERK).Results:AICAR (500 μmol/L) significantly inhibi-ted the proliferation of CaSki cells treated for 24,48,and 72 h as determined by cellcount.The cells at the G_1 and G_2 phases were dramatically decreased while cells atthe S phase were increased in response to AICAR treatment for 24,48,and 72 h.The MTT assay showed less viable cells and Hoechst fluorescent staining showedmore apoptotic cells upon AICAR stimulation.The results of the Annexin-Vstaining demonstrated a time-dependent increase of apoptosis in cells treatedwith AICAR for 24,36,and 48 h.Furthermore,AICAR activated caspase-3 in atime-dependent manner.It was also found that AICAR inhibited the phosphory-lation of AKT and mTOR,which are important kinases regulating cell growth andsurvival.AICAR stimulation obviously increased the expression of the tumorsuppressor p53 and the phosphorylation of ERK.Conclusion:AICAR inhibitedproliferation and induced S phase arrest and promoted apoptosis in CaSki cells,which might be mediated by the downregulation of the AKT/mTOR pathway andthe upregulation of the p53/ERK pathway. Aim: The aim of the present study was to determine the effect of 5-aminoimidazole-4-carboxamide-ribonucleoside (AICAR) on proliferation, cell cycle, and apoptosis in the human epithelial cervical cancer cell line CaSki cells. Methods: Cell count and 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide assay were used to determine cell proliferation and viability. Hoechst 33258 staining was con-ducted to the apoptotic cells. Cell cycle and Annexin-V / propidium iodide staining were analyzed by fluorescence-activated cell sorting (FACS). Western blot assay was used to evaluate the expression of AKT (also known as protein kinase B), mammalian target of rapamycin (mTOR), p53, and extracellular signal- regulated kinase (ERK) : AICAR (500 μmol / L) significantly inhibi- ted the proliferation of CaSki cells treated for 24, 48, and 72 h as determined by cell count. The cells at the G_1 and G_2 phases were dramatically decreased while cells atthe S phase were increased in response to AICAR tre atment for 24, 48, and 72 h. The MTT assay showed less viable cells and Hoechst fluorescent staining showed more apoptotic cells on AICAR stimulation. the results of the Annexin-V staining demonstrated a time-dependent increase of apoptosis in cells treated with AICAR for 24, 36, and 48 h.Furthermore, AICAR activated caspase-3 in a time-dependent manner. It was also found that AICAR inhibited the phosphorylation-of AKT and mTOR, which are important kinases regulating cell growth andsurvival. AICAR stimulationarently increased the expression of the tumors suppressor p53 and the phosphorylation of ERK. Conflusion: AICAR inhibited proliferation and induced S phase arrest and promoted apoptosis in CaSki cells, which might be mediated by the downregulation of the AKT / mTOR pathway and the upregulation of the p53 / ERK pathway.