S100A2基因在结直肠癌组织中的表达、突变及杂合性缺失

Expression,mutation and deletion of S100A2 gene in human colorectal carcinoma

目的:探讨S100A2基因在结直肠癌发生及演进过程中的作用.方法:对66例结直肠癌组织标本进行DNA、mRNA及蛋白提取.采用PCR-SSCP和微卫星结合PCR-变性聚丙烯酰胺凝胶电泳技术检测S100A2基因DNA突变及缺失;分别以RT-PCR技术、Western blot检测S100A2 mRNA及蛋白表达水平.结果:66例结直肠癌组织标本中,未发现S100A2基因存在杂合性缺失(LOH)及第二外显子和第三外显子突变;S100A2 mRNA及蛋白表达水平在结直肠癌中明显低于正常结直肠组织(0.499±0.307vs1.187±0.264;0.542±0.193vs1.301±0.233,均P<0.05).结论:S100A2蛋白表达下调可能与结直肠癌的发生发展有关.S100A2基因在结直肠癌中表达下调可能不是杂合性缺失或突变所致.

METHODS： DNA, mRNA and protein were extracted from 66 colorectal carcinoma specimens. Single strand conformation polymoerphism （SSCP） and microstatellites denaturing PAGE gel electrophoresis analysis were used to detect the mutation and loss of heterozygosity （LOH） of S100A2 gene. The S100A2 mRNA and protein were detected by using reverse transcription chain reaction （RT-PCR） and Western blot. RESULTS： No mutation in exon 2, 3 or deletion of S100A2 was found. RT-PCR and Western blot indicated expression of S100A2 were significantly lower in colorectal carcinoma than in adjacent normal colorectal lesions （0.499 ± 0.307 vs 1.187 ± 0.264; 0.542 ± 0.193 vs 1.301 ± 0.233, both P 〈 0.05）. CONCLUSION： The expression of S100A2 gene was down-regulated in colorectal carcinoma, suggesting a possible involvement of $100A2 gene in carcinogenesis and progression of colorectal carcinoma. The reduced level of S100A2 in colorectal carcinoma may not be attributed to the deletion and mutation of S100A2 gene.