Preliminary Study Of The Effects Of ELF On The Apoptosis And Related Genes Expression In Hepatoma Cell Lines

Objective (1) To examine the effects of extremely low frequency electromagnetic field (ELF) on cellular proliferation and apoptosis in hepatoma cell lines, which may indicate the role of ELF on the treatment of hepatic cell cancer (HCC). (2) To examine the effects of ELF on the expression of apoptotic genes in hepatoma cell lines, which may indicate the molecular mechanisms involved in the effects of ELF on hepatoma cells.Methods MTT assay was used to explore the cell growth in hepatoma cell line BEL-7402 and normal hepatic cell line L-02 and BEL-7402 cell lines after the treatment of ELF;. Flow cytometry was used to examine the apoptosis on BEL-7402 and L-02 and BEL-7402 cell lines after the treatment of ELF. The expression of apoptotic genes was analyzed by real-time PCR and western-blot on mRNA and protein level in BEL-7402 cells and L-02 cells. The selected candidate genes were confirmed by immunohistoche-mistry in 20 specimens of HCC and adjacent noncancerous tissues.Results (1) Compared to that in L-02 cells without ELF treatment, proliferation in twentieth and thirtieth generation L-02 cells were slightly decreased. There was no significant difference in proliferation rates in eleventh generation L-02 cells and control cells. Proliferation of BEL-7402 cells was obviously reduced in eleventh generation cells, and proliferation of twentieth and thirtieth generation cells were significantly reduced after the treatment of ELF. (2) After the treatment of ELF in L-02 cells, the percentage of apoptotic cells in eleventh, twentieth and thirtieth generation cells had no significant changes (the apoptotic rates were as follows:1.72±1.24%,2.34±1.31% and 2.86±1.45%). A increased percentage of apoptotic cells in the eleventh, twentieth and thirtieth generation BEL-7402 cells was observed compared to that in corresponding control cells (P<0.05) and compared to that in L-02 cells (P<0.05). (3) The expression of Bax was significantly increased (P<0.05) on mRNA and protein level in BEL-7402 cells after the treatment of ELF. However, an obvious decrease was found on the expression of Bcl-2, SODD and Survivin on mRNA and protein level in BEL-7402 cells after the treatment of ELF. (4) The positive rates of Bcl-2, SODD and Survivin were significantly higher in HCC than in adjacent noncancerous tissues.Conclusions (1) ELF has no effects on the proliferation in L-02 cells, however an inhibition of proliferation is found in BEL-7402 cells. (2) ELF can promote the apoptosis in BEL-7402 cells and has no effects on apoptosis in L-02 cells. (3) ELF has effects on gene expression of apoptotic genes in the hepatoma cell lines, in which the expression of Bax were increased and Bcl-2, SODD and Survivin were decreased on mRNA and protein level. (4) Therefore, ELF may inhibit proliferation and facilitate apoptosis in the hepatoma cell lines, indicating ELF may play a role in the treatment of live cancer in near further.