非小细胞肺癌中KAI1基因表达及其与P53的相关性研究

Expression of KAI1 gene in non-small cell lung cancer and its relationship with P53

背景与目的近年研究表明,KAI1表达下调与多种肿瘤的转移有关,但其与非小细胞肺癌的关系研究较少,且导致其下调的机制尚未明确。本研究从mRNA和蛋白水平探讨KAI1基因在非小细胞肺癌组织中的表达与患者临床病理特征的关系及其与突变型P53蛋白表达的关系。方法采用RTPCR和Westernblot法,检测48例肺癌患者手术切除的新鲜癌组织标本中KAI1mRNA、KAI1/CD82及突变型P53蛋白的表达,20例肺部良性疾病组织和正常肺组织作为对照。结果肺癌组和对照组中KAI1mRNA的阳性率分别为52%和90%(P<0.01),KAI1/CD82蛋白的阳性率分别为48%和85%(P<0.01),突变型P53蛋白阳性率分别为65%和5%(P<0.01)。KAI1mRNA、KAI1/CD82和突变型P53蛋白阳性率与肺癌患者临床分期、细胞分化程度和淋巴结转移有密切关系(P<0.05或P<0.01)。肺癌组织中KAI1mRNA与KAI1/CD82表达呈密切相关性(P<0.01),KAI1/CD82与突变型P53蛋白的表达亦呈显著相关性(P<0.05),KAI1mRNA与突变型P53表达无明显相关性(P>0.05)。结论KAI1基因的低表达可能与非小细胞肺癌的发生、发展和转移有关;其下调的机制可能主要发生在转录水平并与p53基因有关,二者可能作为评估肺癌患者转移潜能的指标。

Background and objective Recent researches have manifested that down-regulation of KAI1 relates to metastasis in various tumors, but its association with non-small cell lung cancer (NSCLC) and the mechanism for its down-regulation are not clear. The aim of this study is to investigate the expression of KAI1 in NSCLC and its relationship with clinicopathological characteristics and mutant P53 protein. Methods The expression of KAI1/CD82 and mutant P53 protein was detected in 48 cases of NSCLC tissues by Western blot, and KAI1 mRNA was detected by RT-PCR method, with 20 cases of pulmonary benign disease tissues and normal lung tissues as control. Results The positive rate of KAI1 mRNA was 52% in lung cancer group and 90% in control group, respectively (P<0.01), KAI1/CD82 was 48% and 85% respectively (P<0.01), and mutant P53 protein was 65% and 5% respectively (P<0.01). The positive rate of KAI1 mRNA, KAI1/CD82 and mutant P53 protein closely related to the tumor stages, cell differentiation and lymph node metastasis status (P<0.05 or P<0.01). The expression of KAI1/CD82 highly related to KAI1 mRNA (P<0.01) and mutant P53 protein (P<0.05), while expression of KAI1 mRNA did not relate to mutant P53 protein expression (P>0.05). Conclusion The down-regulation of KAI1 may relate to carcinogenesis, development and metastasis of NSCLC. Its reduction may occur mainly at transcriptional level and correlate with p53 in NSCLC. KAI1 and p53 might be helpful to predict the potential metastasis of NSCLC.