Abstract: ObjectiveTo study the growth inhibitation action of gossypol derivatives,ApoG2 on the prostatic cancer PC-3 cells,and make the primary study about their anti-tumor mechanism. MethodsThe MTT analytical method,AO staining,transmission electron microscope, flow cytometer and Western blot for measuring the apoptosis related proteins were used to study the growth inhibition and induction of autophagy roles of ApoG2 on the prostatic cancer PC-3 cells in vitro. ResultsWhen the concentration of ApoG2 was higher than 2.5 μg/ml in solution,it had the obvious proliferation inhibition ability to the prostate cancer PC-3 cells in vitro,and it had the charcteristics of time and dose dependent. When ApoG2 was used for the treatment of PC-3 cell for 72 hours,the observation with AO staining and transmission electron microscope indicated that ApoG2 could obviously induce the autophagy of prostate cancer cells. The measurement results by the flow cytometer indicated that the apoptosis of prostate cancer cells induced by ApoG2 might be strengthened by the use of autophagic inhibitor 3-MA. The measurement of Bcl-2 expressions by the Western blot found that after ApoG2 at the concentration of 10.0 μg/ml was used for treatment of prostate cancer cells for 48 hours,the expression level of Bcl-2 decreased. The Beclin 1 and LC-3Ⅱexpressions in the tumor cells were obviously increased by immunohistochemistry method after ApoG2 treatment. ConclusionApoG2 has the same obvious anti-proliferation role to the prostatic cancer PC-3 cells in vitro and its mechanism is to mainly induce the autophagy of tumor cells and to secondarily induce their death,the inhibition of autophagy may promote the occurrence of death.