Objective:To investigate expressions of LDHA,CD56 and NKG2D in liver cancer tissues,and to further explore effects and correlations of Bufalin(BF)on LDHA and NK cells in hepatocellular carcinoma.Methods:Immunohistochemistry(IHC)was used to detect differential expressions of LDHA and NK cell specific molecular markers CD56 and NKG2D in 91 postoperative paraffin pathological specimens of hepatocellular carcinoma,as well as correlation between these markers in cancer and adjacent tissues.A Hepa1-6 subcutaneous tumor bearing hepatocellular carcinoma model was constructed by C57BL/6 mice and randomly divide into Control(Ctrl)group,BF+Pyruvic acid(BF+PA)group,Oxamate(OX)group,BF group,with 5 mice per group.Growth rate and volume of subcutaneous tumors were observed;IHC was used to detect expressions of LDHA and mouse NK cell specific molecular markers NK1.1 and NKG2D in tumors of each group of mice;ELISA was used to detect concentrations of perforin,TNF-α and IFN-γ in serum of mice in each group.Results:LDHA was highly expressed in human liver cancer tissues(P<0.001),while CD56 and NKG2D were highly expressed in adjacent tissues(P<0.001);LDHA expression was negatively correlated with CD56(r=-0.529 8,P<0.000 1)and NKG2D(r=-0.320 1,P<0.001);CD56 expression was positively correlated with NKG2D(r=0.612 2,P<0.000 1).Subcutaneous tumor experiment of mouse hepatocellular carcinoma showed that compared with Ctrl group and BF+PA group,subcutaneous tumor growth rate of OX group and BF group slowed down and showed a trend of tumor reduction;IHC detection showed that compared with Control group,LDHA expression in BF group was significantly downregulated(P<0.01),NK1.1 and NKG2D expressions were significantly increased(P<0.000 1);ELISA showed that compared with Ctrl group,LDHA in serum of BF group increased perforin,TNF-α,IFN-γ expressions(P<0.000 1),and enhanced NK cell killing ability.Conclusion:BF can inhibit LDHA expression in hepatocellular carcinoma cells and increase infiltration rate of NK cells in hepatocellular carcinoma tissues,which may enhance killing ability of NK cells in tumor microenvironment and inhibit growth of hepatocellular carcinoma.

Objective:To investigate expressions of LDHA,CD56 and NKG2D in liver cancer tissues,and to further explore effects and correlations of Bufalin(BF)on LDHA and NK cells in hepatocellular carcinoma.Methods:Immunohistochemistry(IHC)was used to detect differential expressions of LDHA and NK cell specific molecular markers CD56 and NKG2D in 91 postoperative paraffin pathological specimens of hepatocellular carcinoma,as well as correlation between these markers in cancer and adjacent tissues.A Hepa1-6 subcutaneous tumor bearing hepatocellular carcinoma model was constructed by C57BL/6 mice and randomly divide into Control(Ctrl)group,BF+Pyruvic acid(BF+PA)group,Oxamate(OX)group,BF group,with 5 mice per group.Growth rate and volume of subcutaneous tumors were observed;IHC was used to detect expressions of LDHA and mouse NK cell specific molecular markers NK1.1 and NKG2D in tumors of each group of mice;ELISA was used to detect concentrations of perforin,TNF-α and IFN-γ in serum of mice in each group.Results:LDHA was highly expressed in human liver cancer tissues(P<0.001),while CD56 and NKG2D were highly expressed in adjacent tissues(P<0.001);LDHA expression was negatively correlated with CD56(r=-0.529 8,P<0.000 1)and NKG2D(r=-0.320 1,P<0.001);CD56 expression was positively correlated with NKG2D(r=0.612 2,P<0.000 1).Subcutaneous tumor experiment of mouse hepatocellular carcinoma showed that compared with Ctrl group and BF+PA group,subcutaneous tumor growth rate of OX group and BF group slowed down and showed a trend of tumor reduction;IHC detection showed that compared with Control group,LDHA expression in BF group was significantly downregulated(P<0.01),NK1.1 and NKG2D expressions were significantly increased(P<0.000 1);ELISA showed that compared with Ctrl group,LDHA in serum of BF group increased perforin,TNF-α,IFN-γ expressions(P<0.000 1),and enhanced NK cell killing ability.Conclusion:BF can inhibit LDHA expression in hepatocellular carcinoma cells and increase infiltration rate of NK cells in hepatocellular carcinoma tissues,which may enhance killing ability of NK cells in tumor microenvironment and inhibit growth of hepatocellular carcinoma.