REGgamma在胃癌组织与不同分化胃癌细胞株中的表达及其临床意义

Expression and Clinical Significance of REGgamma in Gastric Cancer Tissue and Various Differentiated Gastric Cancer Cell Lines

目的:探讨REGgamma(REGγ)在胃癌组织与不同分化细胞株中的表达水平及其临床意义。方法:应用免疫组化SP法检测70例胃癌组织和30例正常胃组织中REGγ/蛋白的表达水平,并分析其与胃癌生物学行为的关系:分别采用逆转录-聚合酶链反应(RT-PCR)及Western blot检测正常胃粘膜细胞株(GES-1)、胃癌高分化(MKN-28)、中分化(SGC-7901)和低分化(BGC823)细胞株中REGγ mRNA转录情况和蛋白表达水平。结果:免疫组化结果表明在胃癌组织中,REGγ蛋白的表达阳性率(74.3%)显著高于正常胃粘膜组织(40.0%,P<0.01),且表达与肿瘤的大小(P<0.01)、淋巴结转移(P<0.05)、分化程度(P<0.01)、浸润程度(P<0.01)及远处转移(P<0.05)相关;RT-PCR结果表明在正常胃粘膜细胞株及胃癌高、中、低分化细胞株中,REGγ mRNA表达水平逐渐增强,分别为0.459±0.079、0.588±0.118、0.715±0.066、0.873±0.099(P<0.01),Western blot结果表明在正常胃粘膜细胞株及胃癌高、中、低分化细胞株中,REGγ蛋白表达水平逐渐增强,分别为0.712±0.065、1.176±0.185、1.533±0.127、2.061±0.398,结果差别有统计学意义(P<0.05)。结论:REGγ在正常胃粘膜组织和胃癌组织中呈一定比例的阳性表达,其表达水平与胃癌癌肿大小、是否有淋巴结转移、分化程度、浸润程度及是否远处转移等肿瘤的恶性生物学行为有关。REGγ表达与胃癌的分化程度相关,随着细胞分化程度的降低其表达逐渐增强,检测REG7 mRNA及蛋白的表达可望成为胃癌早期诊断和判断预后的分子指标之一。

Objective： To evaluate the expression and clinical significance of REGγ in gastric cancer tissue and various differentiated gastric cancer cell lines. Methods： Immunohistochemistry was used to detect the expression of REGγ protein in specimens from 70 cases of gastric cancer and 30 normal gastric mucosa tissue. The correlation between the expression of REGγ protein and the tumor biological behavior was analyzed. RT-PCR and Western blot were used to detect the mRNA levels and the protein expression of REGγ in normal gastric cell line （GES-1）, well differentiated gastric cancer cell line （MKN-28）, moderately differentiated gastric cancer cell line （SGC-7901） and poorly differentiated gastric cancer cell line （BGC823）. Results： Immunohistochemical staining results showed that the positive rate of REGγ protein expression in gastric cancerous tissue （52/70, 74.29%） was significantly higher than that in normal gastric tissue （12/30, 40%） （P〈0.01）. The expression of REGy was correlated with tumor size （P〈0.01）, lymph node metastasis （P〈0.05）, differentiation degree （P〈0.01）, invasion degree （P〈0.01）, and distant metastasis （P〈0.05）. RT-PCR analysis showed that the expression of REGymRNA was （0.459±0.079） in normal gastric mucosa cell line, （0.588±0.118） in well differentiated gastric cancer cell line, （0.715±0.066） in moderately differentiated gastric cancer cell line, and （0.873±0.099） in poorly differentiated gastric cancer cell line, respetively, showing an increasing trend. Western blot analysis showed that the expression of REGy protein was （0.712±0.065） in normal gastric mucosa cell line, （1.176±0.185） in well differentiated gastric cancer cell line, （1.533±0.127） in moderately differentiated gastric cancer cell line and （2.061±0.398） in poorly differentiated gastric cancer cell line, respetively, showing an increasing trend （P〈0.05）. Conclusion： There were certain degree of REGy expression in gastric cancer tissues and normal gastric tissue. The expression of REGy was correlated with tumor size, lymph node metastasis, differentiation degree, invasion degree and distant metastasis. The expression of REGy increased gradually in mucosa cell line, well differentiated gastric cancer cell line, moderately differentiated gastric cancer cell line and poorly differentiated gastric cancer cell line. Detection of the expression of REGy mRNA and protein may be useful for the early diagnosis and prognosis evaluation of gastric cancer.