摘要
目的探讨piR-9994在胃癌中的表达及其与临床病理特征的关系,并分析其与PIWIL4表达的相关性。方法采用qRT-PCR法检测76例胃癌及癌旁组织中piR-9994的表达,采用免疫组化En Vision法检测PIWIL4的表达,并复习相关文献。结果 piR-9994在胃癌组织中的表达比癌旁组织上调2. 3倍(P=0. 002 2)。Ⅲ+Ⅳ期胃癌组piR-9994的表达比Ⅰ+Ⅱ期胃癌组上调3. 5倍(P=0. 002),神经侵犯组比未侵犯组上升2. 5倍(P=0. 036)。PIWIL4在胃癌组织中的表达明显高于癌旁组织(χ2=18. 346,P <0. 001),其中Ⅲ+Ⅳ期胃癌组高于Ⅰ+Ⅱ期胃癌组(χ2=8. 60,P=0. 003)。胃癌组织中piR-9994的表达与PIWIL4表达呈正相关(r=0. 231,P <0. 05)。结论 piR-9994在胃癌组织中过表达并与肿瘤分期、神经侵犯密切相关,piR-9994可能通过调节PIWIL4表达促进胃癌的发生、发展,piR-9994有望成为判断胃癌恶性程度及预后的分子标志物。
Purpose To explore the relationship between the expression level of piR-9994 in gastric cancer and its clinical pathological features,and to analyze its correlation with PIWIL4 expression. Methods Express of piR-9994 and PIWIL4 in 76 cases of human gastric cancer tissue with different clinical stage and differentiated degree and matching adjacent tissue were detected by qRT-PCR and immunohistochemistry,respectively.Results The expression of piR-9994 in gastric cancer was 2. 3times higher than that in paracancerous tissues( P = 0. 002 2).The expression of piR-9994 in stage Ⅲ + Ⅳ gastric cancer was3. 5 times higher than that in stage Ⅰ + Ⅱ( P = 0. 002),and the expression of piR-9994 in cancers with nerve invasion was 2.5 times higher than that in cancers without invasion( P =0. 036). The positive expression of PIWIL4 in gastric cancer tissues was significantly higher than that in adjacent tissues( χ~2=18. 346,P < 0. 001),and the expression of PIWIL 4 in stageⅢ + Ⅳ gastric cancer group was higher than that stage Ⅰ + Ⅱgastric cancer group( χ2= 8. 60,P = 0. 003). There was a positive correlation between piR-9994 expression and PIWIL4 expression in gastric carcinoma( r = 0. 231,P < 0. 05). Conclusion piR-9994 overexpression in gastric cancer tissues is closely related to tumor staging and nerve invasion,and piR-9994 may pro-mote the occurrence and progression of gastric cancer by regulating PIWIL4 expression. piR-9994 may be a molecular markers for judging malignant degree and prognosis of gastric cancer.
引文
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