Effects Of Melittin Combined With Gemcitabine On The Human Pancreatic Cancer Panc-1 Cells

Objective:To explore the effects and potential mechanisms of melittin with or without gemcitabine on the human pancreatic cancer Panc-1 cells.Methods:This study inclued melittin group(16 μg/m L 、8μg/m L、4μg/m L 、2μg/m L melittin)、gemcitabine group(8μg/m L、4μg/m L、2μg/m L、1μg/m L gemcitabine)、combination group(16 μg/m L melittin +8μg/m L gemcitabine 、8 μg/m L melittin +4μg/m L gemcitabine、4 μg/m L melittin +2μg/m L gemcitabine、2 μg/m L melittin +1μ g/m L gemcitabine) and control group(without any drug intervention).The cell proliferation was detected by CCK-8 ? assay for different groups,then median-effect principle was used to analyze the effiects of the two drugs in combination.Cell apoptosis wased determined by flow cytometry. The expression of caspase-3、caspase-8、caspase-9、STAT3 and p STAT3 was evaluated by Western-blot analysis.Results:melittin and gemcitabine both inhibited Panc-1 cell proliferation in concentration-dependent manner,and the inhibition effect was more significantly while treated by melittin combinated with gemcitabine( p<0.05).median-effect principle prompted the combination of melittin and gemcitabine have a synergistic effect(CI <1).FCM analysis showed all the three groups could induce cell apoptosis and the fraction of apoptotic cells for the three groups were more significantly(p<0.05) compared with control group,what’more,the apoptosis rate of the combination group was significantly higher than monotherapy groups(p<0.05).Westen blot analysis showed that there is no significantly difference in the expression of STAT3 between all the three experimental groups and control group(P>0.05).compared with control group,gemcitabine had nosignificantly impact on the p STAT3 level(P>0.05),however p STAT3 level was reduced in melittin and combination group,especially in combination group. All the three experimental groups could promote Caspase-3 expression compared with control group,especially in combination group.gemcitabine had no significantly impact on the Caspase-8 expression(P>0.05),Caspase-8 level decreased significantly after melittin and combination drug treatment.Caspase-9 level was significantly decreased in all the three experimental groups compared with control group,especially in combination group.Conclusion:our study revealed that not only does melittin inhibit proliferation and induce apoptosis of Panc-1 cell,but melittin combined with gemcitabine also showed a synergistic antitumor activity against Panc-1 cell,the possible mechanism is attributed to the decrease of p STAT3 and promoting the expression of Caspase- 3 、 Caspase- 8 、Caspase- 9 via intrinsic and extrinsic apoptotic pathways.