Effects of Recombinant Human Growth Hormone on the Proliferation and the Expression of GHR of Human Liver Cancer     Cell in Vitro

Lu Ying-zhi²,Li Su-yi¹, ,Tan Hua-yang¹, LinYan³,Yang Fang⁴, He Xiang-ming¹.

Li Su-yi：通讯作者lisuyi@csco.org.cn

(1.Department of Oncology,Medical College,Southeast University, Nanjing 210009, China; 2. Department of Oncology,the second People Hospital of Lianyungang,Lianyungang 222023, China;3.Department of Oncology,the Affiliated second Hospital of Nanjing Medical University,Nanjing 210000,China;4.Department of Biomedical Engineering,Southeast University;Key Laboratory of Materials and Devices in Jiangsu Province,Nanjing 210009, China )

Abstract: [Purpose]  To investigate the effects of recombinant human growth hormone (rhGH) on human liver cancer cells expressed different growth hormone receptors (GHR) in vitro.[Methods]Four groups were assigned according to the cell lines treatment modes: untreated group, 50ng/ml rhGH treated group, 100ng/ml rhGH treated group and 200ng/ml rhGH treated group. The expression of GHR in human liver cancer cell lines was detected by immunohistochemistry, fluorescence and radioligand assays. By MTT, CFSE and ELISA, effects with different concentrations of rhGH on the cell proliferation rate of human liver cancer cell lines were analyzed.[Results] HepG-2 in which GHR was high-expressed: compared with the untreated group,  the 24 hours growth rates of 50ng/ml rhGH treated group, 100ng/ml rhGH treated group and 200ng/ml rhGH treated group were significantly increased by 107.705%、114.181%、107.406% (P<0.05) , the 48 hours growth rates were 109.594%、114.156%、109.292% (P<0.05). The fluorescence intensities of CFSE were significantly decreased (P<0.05) . The concentrations of IGF-Ⅰin the four groups were 173.86±27.46、236.94±19.07、247.16± 14.56、217.94±33.61pg/ml. Compared with the untreated group, it significantly increased in groups with different concentrations of rhGH (P<0.05) . By fluorescence, the expressions of GHR significantly increased in the treated groups (P<0.05) . By radioligand assays, the GHR site of the untreated group was 7.5137±0.5352 (10^³/cell) , with the sites of 50ng/ml rhGH treated group, 100ng/ml rhGH treated group and 200ng/ml rhGH treated group were respectively 8.4350±0.2396、9.3957±0.5143、8.3297±0.3133 (10^³/cell)(P<0.05) . But there was no notable effect on SMMC7721 in which GHR was low-expressed and QGY-7701 without expression of GHR(P>0.05).[Conclusions] rhGH could promote the growth of tumor cell lines and increase the expression of GHR in which GHR was high-expressed, such as HepG-2 and so on. However, such effects were not notable on tumor cells in which GHR was low-expressed or no-expressed in vitro.

Keywords: Recombinant human growth hormone; Growth hormone receptor; Insulin-like growth factor-Ⅰ; Liver neoplasms