[The effects of recombinant human growth hormone on the proliferation of Bel-7402 human hepatic carcinoma cell lines in vitro and its regulation on growth hormone receptors].

OBJECTIVE: To investigate the role of recombinant human growth hormone (rhGH) in the growth of Bel-7402 human hepatic carcinoma cell line (Bel-7402 line) in vitro and its effects on GHR expression. METHODS: Tumor cell count, MT assay and colony forming test were performed to determine the responses of Bel-7402 to different concentrations of rhGH (0, 1, 10, 100, 1000, 10 000 ng/ml). Metabolism of DNA in tumor cells was analyzed with the method of mixture of 3H-TdR. Radioreceptor assay was used to detect the GHR expression of the hepatic carcinoma cell lines and its relation to different rhGH concentrations. RESULTS: rhGH accelerated the proliferation of the Bel-7402 line when the concentration of rhGH was over 100 ng/ml (P < 0.05). Other rhGH concentrations had also positive effects, but with reduced effect as compared with that of 100 ng/ml. After 24 h of rhGH addition of concentration of 10 ng/ml and 100 ng/ml, GHR site number was significantly higher than that in control group, while the 10,000 ng/ml group showed a significantly lower GHR site number. CONCLUSIONS: Different concentrations of rhGH might result in variable effects on the growth of Bel-7402 hepatic carcinoma cell line. Certain concentrations of rhGH might stimulate the growth of the cell line. rhGH can regulate the expression of GHR in the cell line.