Clinical significance of SQSTM1/P62 and nuclear factor-κB expression in pancreatic carcinoma

BACKGROUND Overexpression of SQSTM1(sequestosome 1,P62)and nuclear factor-κB(NF-κB)plays an important role in the invasion and metastasis of a variety of malignant tumors.AIM To explore the expression of P62 and NF-κB in pancreatic cancer and their relationship with clinicopathological features.METHODS The expression levels of P62 and NF-κB were analyzed by immunohistochemistry with a tissue chip containing 40 cases of human pancreatic carcinoma.Then we analyzed the correlation among P62 expression,phospho-P65 expression,and clinicopathological features of pancreatic carcinoma samples.RESULTS P62 expression was mainly observed in the cytoplasm of pancreatic carcinoma cells.Phosphorylated P65(phospho-P65)was mainly expressed in the nucleus and cytoplasm of pancreatic carcinoma cells.There was a significant difference in P62 expression among T stages.And a significant difference in phosphor-P65 expression among pathology types was noted.In the cases with strongly positive P62 expression,significant differences were found in age.And there were significant differences in T stage and tumor-node-metastasis stage in the cases with strongly positive phosphor-P65 expression.CONCLUSION In pancreatic carcinoma,P62 expression is significantly correlated with T stage.It may be a valuable malignant indicator for human pancreatic carcinoma.

p62参与人恶性黑色素瘤细胞NF-κB活性调控

目的探讨多功能蛋白p62参与调控人恶性黑色素瘤细胞NF-κB活性的机制。方法选取人恶性黑色素瘤标本20例,免疫组化方法检测p50、p65、p62表达。人黑色素瘤A375细胞,转染p62-siRNA特异性表达载体。MTT法检测细胞生存率,western blot检测p62蛋白表达,NF-κB荧光素酶报告基因分析检测NF-κB活性。结果 Spearman等级相关性分析p50与p65、p65与p62表达呈正相关均有统计学意义(P<0.05)。与对照组相比,A375细胞转染p62-siRNA特异性表达载体24h、48h和72h,p62蛋白表达、细胞生存率和NF-κB活性均明显降低(P<0.05)。结论人恶性黑色素瘤中p62表达与NF-κB高表达呈正相关,降低p62表达能通过抑制NF-κB活性降低A375细胞存活率,表明p62参与NF-κB活性调控。