Abstract:

To investigate the influence of silenced poly-（ADP-ribose）glycohydrolase（PARG）on the expression and phosphorylation of protein kinase P38 in colorectal carcinoma lovo cells and clarify its mechanism.  Methods Lentivirus PARG-shRNA was transfected into colorectal carcinoma lovo cells，then the lovo cells with silenced PARG was perpetually selected. Untreated lovo cells were used   as positive control(untransfected group)，the lovo cells  treated with empty vector were used as   negative control  (empty-vector-transfected group)，the lovo cells   treated with PARG-shRNA were used  as   experimental comparison(PARG- shRNA transfected group). The expression of PARG mRNA was detected by RT-PCR. The expressions of PARG，poly-（ADP-ribose）polymerases（PARP），P38 and p-P38 protein were detected by Western blotting.  Results Both RT-PCR and Western blotting results showed that the expressions of PARG in PARG-shRNA transfected group was obviously lower than that in untransfected group（P<0.05）. The expressions of PARP，P38 and p-P38 in PARG-shRNA transfected group were obviously lower than that in untransfected group（P<0.05）．
Conclusion The silenced PARG can inhibit the expression and phosphorylation of P38 in human colorectal carcinoma lovo cells. It  may be related to down-regulating PARP .

Key words: colonic neoplasms；poly-（ADP-ribose）
glycohydrolase；poly-(ADP-ribose）polymerases；P38；Lentivirus-shRNA