bFGF促进人大肠癌LoVo细胞增殖的信号转导机制  

Signal transduction mechanism of basic fibroblast growth factor in promoting the growth of colorectal cancer LoVo cell line

作　　者：周颖[1] 王桂玲[1] 

机构地区：[1]中国医科大学基础医学院细胞生物学教研室,辽宁省沈阳市110001

出　　处：《世界华人消化杂志》2007年第1期34-38,共5页World Chinese Journal of Digestology

摘　　要：目的:通过改变碱性成纤维细胞生长因子(bFGF)作用于LoVo细胞的时间,检测PKB活性和CyclinA的表达情况,进一步研究bFGF通过PI3-K/PKB通路调控大肠癌细胞生长的信号转导机制.方法:MTT法分析bFGF对LoVo细胞增殖程度的影响;(γ-32P)ATP掺入法检测大肠癌LoVo细胞株中PKB的活性;RT-PCR法检测大肠癌LoVo细胞株中CyclinA的表达;Westernblot法检测bFGF作用LoVo细胞后CyclinA的表达.结果:bFGF以不同时间作用于LoVo细胞时,通过(γ-32P)ATP掺入法检测发现其可提高细胞PKB活性,PI3-K的抑制剂LY294002预处理后再施加bFGF,可显著降低PKB的活性,两者相比差异显著[704.32±12.35pmol/(mg·min)vs1352.79±19.85pmol/(mg·min),P<0.05].bFGF刺激LoVo细胞时CyclinA蛋白和CyclinAmRNA表达均高于其他各施加因素组,而PI3-K的抑制剂LY294002组的CyclinA蛋白和CyclinAmRNA明显降低.结论:bFGF刺激大肠LoVo细胞后可通过依赖PI3-K/PKB途径调节CyclinA的转录活性,促进其表达,进而促进细胞增殖.AIM： To investigate the activity of protein kinase B （PKB） and the expression of Cyclin A in colorectal cancer LoVo cell line after treatment of basic fibroblast growth factor （bFGF）, and to further analyze the signal transduction mechanism of bFGF in regulating the growth of LoVo cells via PI3-K/PKB pathway. METHODS： Colorectal cancer cell line LoVo was cultured in vitro using routine method, and then treated with bFGF, LY294002 （inhibitor of PI3-K）, and bFGF plus LY294002, respectively. MTT assay was used to determine the proliferaion of LoVo cells; PKB activity in LoVo cells was measured by （γ-^32P）ATP incorporation assay; Cyclin A mRNA expression was examined by reverse transcription-polymerase chain reaction （RT-PCR）; Cyclin A protein expression was detected by Western blot. RESULTS： The activity of PKB was increased in LoVo cells after bFGF treatment at different time, but it was decreased by LY294002 pretreatment [704.32 ± 12.35 pmol/（mg · min） vs 1352.79 ± 19.85 pmol/（mg ·min）, P 〈 0.05]. The expression of Cyclin A was significantly increased at both protein and mRNA levels in the cells treated by bFGF, but the up-regulation of Cyclin A was obviously inhibited by LY294002 pre-treatment. CONCLUSION： Via PI3-K/PKB pathway, bFGF can regulate the transcriptional activity of Cyclin A and modulate its expression in LoVo cells, which may promote the proliferation of colorectal cancer cells.

关 键 词：碱性成纤维细胞生长因子 蛋白激酶B CYCLIN A 大肠癌 

分 类 号：R735.34[医药卫生—肿瘤]