Effects Of Parthenolide And Portein Kinase C Inhibitor On Proliferation And Apoptosis Of Human Gastrointestinal Stromal Tumors Cell Lines

OBJECTIVE To investigate the effects of Parthenolide and Portein Kinase C inhibitor on proliferation and apoptosis of human Gastrointestinal Stromal Tumors cell lines and its possible mechanism.METHODS The GIST cells (GIST-882) were cultured in vitro. MTT assay was used to measure the proliferation inhibition rates of human GIST cells which were treated with PTL and PKC inhibitor by different concentrations and combined with thePTL and PKC inhibitor. Flow cytometry was used to evaluate the rate of early stage apoptosis. Morphological changes of GIST cells were observes by invited microscope. The cell scratch test was used to detect the GIST cell migration. Western blotting was used to determine the expression level of endoplasmic reticulum stress related protein GRP78 and GADD153 in GIST cells.RESULTS MTT assay results showed that different concentrations of PTL and PKC inhibitor had effects of growth inhibition (P<0.01), and the effect was in a concentration-dependence. PTL combined with PKC inhibitor could significantly inhibit the proliferation of GIST cells (P<0.01). Flow cytometry results showed that the rate of early cell apoptosis was higher in PTL and PKC inhibitor groups than that the control group after treated 48 hours. The rate of early cell apoptosis was higher in combination group than that the PTL,PKC inhibitor and control groups (P<0.01) Inverted microscope results showed that a little number of cells to become round, with loose connections between cells, easy to fall off from wall in PTL group, and more round cell was easy to fall off from wall, small part of karyopycnosis and karyorrhexis in PKC inhibitor group, and morphological changes were more obviously in the combination group. The cell scratch test results showed that the migration ability was lower in the PTL and PKC inhibitor groups than that the control group (P<0.01), and the migration ability was lowest in the combination group (P<0.01). Western blot results showed that the expression of endoplasmic reticulum stress related proteins GRP78 and GADD153 was higher in PTL and PKC inhibitor groups than that the control group (P<0.01), and compared with the PTL and PKC inhibitor groups, the expression of endoplasmic reticulum stress related proteins GRP78 and GADD153 was obviously higher in the combination group (P<0.01)CONCLUSION 1.PTL and PKC inhibitor have induced apoptosis of GIST cell, and PTL combined with PKC inhibitor have synergistic effects on inducing apoptosis of GIST cell.2.The mechanism of PTL and PKC inhibitor induce apoptosis of GIST cell may be related with the up-regulate expression of endoplasmic reticulum stress related proteins GRP78 and GADD153.