Pharmacodynamics Of ST-01,a Novel Natural Polyamine Modified Compound,Were Studied On Hepatocellular Carcinoma

Objective:In recent years,the targeted antitumor effect of natural polyamine conjugates has attracted widespread attention.In present study,the antitumor effects and molecular mechanism of ST-01,a novel natural polyamine modified compound,were evaluated in human hepatoma Hep G2,SMMC-7721 cells in vitro and tumor-bearing mice in vivo.Methods:The antitumor activity of ST-01 was examined by MTT assay in human hepatoma Hep G2and SMMC-7721 cells.Morphological change was observed by the inverted biological microscope.The effects of different concentrations of ST-01 on autophagy and cell cycle distribution were detected through MDC staining and multidimensional panoramic flow cytometry.In addition,the expression levels of autophagy-related proteins?such as BECN1,p62 and LC3?and cell cycle-related proteins?such as Cyclin B1,Cdc2 and p-Cdc 2?were assessed by Western blot.Furthermore,the H22 tumor-bearing BLAB/c mice model was used to evaluate the effects of ST-01 on prolonged the survival time.Results:The present data demonstrated that ST-01 inhibited the growth of Hep G2 cells and SMMC-7721 cells effectively in a dose-and time-dependent manner,the IC₅₀ were?12.97±2.18??M and?12.46±2.31??M for 24 h,respectively;for 48 h,the IC₅₀ were?4.66±0.53??M and?4.46±0.25??M,respectively.When pre-incubation with 3-MA?an autophagy inhibitor?,the antiproliferative effect of ST-01on Hep G2 cells and SMMC-7721 cells was weakened.MDC staining results showed that ST-01 induced cell autophagy with the increase of ST-01 concentration.Morphological observation and flow cytometry results showed that ST-01 induced Hep G2 cells and SMMC-7721 cell autophagy and cell cycle arrest at G₂/M phase.In addition,the protein expression of BECN1 and LC3-II were up-regulated after treatment with ST-01,accompanied with down-regulation of p62.The change of autophagy-related protein expression could be reversed by 3-MA.Furthermore,the cell cycle-related proteins expression of Cyclin B1 and p-Cdc2 were up-regulated after treatment with ST-01,but Cdc2 was unchanged.ST-01 could also significantly prolong the survival time of H22 tumor-bearing BLAB/c mice,and the life extension rate was65.85%.Conclusions:ST-01 could significantly inhibit proliferation of human hepatocellular carcinoma Hep G2 and SMMC-7721 cells in vitro,and induce cell autophagy and cell cycle arrest at G₂/M phase.Furthermore,ST-01 could also significantly prolong the survival time of H22 tumor-bearing BLAB/c mice.