AIM:To investigate the antiproliferative effect of octreotide,a long-acting analogue of somatostatin,on gastric cancercell line SGC7901 and its possible molecular mechanisms.METHODS:Gastric cancer cell line SGC7901 employed inthe study was treated with 0.008,0.04,0.2,1,5 and 25μg·ml~(-1) of octreotide respectively for 24 h to evaluate theantiproliferative effect of somatostatin analog on the tumorcells by MTT assay method.To elucidate the underlyingmechanism,the cells were exposed to 1 μg·ml~(-1) of octreotidefor 0,12,24 and 48 h,when their Akt/PKB and telomeraseactivities were respectively determined using PCR-ELSIA andnonradioactive protein kinase assay protocols.The sameexperimental procedures were also performed in the controlcells that were treated with corresponding vehicles insteadof somatostatin analog.RESULTS:After exposed to octreotide for 24 h at theconcentrations of more than 1 μg·ml~(-1),SGC7901 cellsexhibited a dose-dependent inhibition of growth with theinhibiting rate to be as high as 34.66% when 25 μg·ml~(-1) ofoctreotide was applied.The Akt/PKB and telomerase activityof SGC7901 cells was significantly inhibited when the cellswere exposed to 1 μg·ml~(-1) of octreotide for 12,24 and 48 hcompared with that of their control counterparts (P<0.01),both of which exhibited in a time-dependent manner.CONCLUSION:The antiproliferative effect of octreotide onSGC7901 cells might be mediated by the inhibition of Akt/PKB and telomerase. AIM: To investigate the antiproliferative effect of octreotide, a long-acting analogue of somatostatin, on gastric cancer cell line SGC7901 and its possible molecular mechanisms. METHODS: Gastric cancer cell line SGC7901 employed in the study was treated with 0.008,0.04,0.2,1, 5 and 25 μg · ml -1 of octreotide respectively for 24 h to evaluate theantiproliferative effect of somatostatin analog on the tumor cells by MTT assay method. To elucidate the underlying mechanism, the cells were exposed to 1 μg · ml -1 of octreotide for 0, 12, 24 and 48 h, when their Akt / PKB and telomeraseactivities were determined determined using PCR-ELSIA and nonradioactive protein kinase assay protocols. also performed in the control cells that were treated with corresponding vehicles instead of somatostatin analog. RESULTS: After exposed to octreotide for 24 h at the concentrations of more than 1 μg · ml -1, SGC7901 cellsexhibited a dose-dependent inhibition of growth with the inhibition rate to be as high as 34.66% when 25 μg · ml -1 ofoctreotide was applied. The Akt / PKB and telomerase activity of SGC7901 cells was significantly inhibited when the cells were exposed to 1 μg · ml -1 of octreotide for 12, 24 and 48 hcompared with those of their control counterparts (P <0.01), both of which exhibited in a time-dependent manner. CONCLUSION: The antiproliferative effect of octreotide on SGC7901 cells might be mediated by the inhibition of Akt / PKB and telomerase.