细胞色素P450花生四烯酸表氧化酶在人肿瘤组织及肿瘤细胞系中的特异性表达

Expression of cytochrome P450 arachidonic acid epoxygenase 2J2 in human tumor tissues and cell lines

背景与目的:细胞色素P450花生四烯酸表氧化酶(cytochrome P450 arachidonic acid epoxygenase 2J2,CYP2J2)作为花生四烯酸的新型代谢途径,在人体中的生物学及病理生理学意义还远未被认识和阐明。本研究主要探讨CYP2J2基因在人类肿瘤组织及肿瘤细胞系中的表达及其意义。方法:采用RT-PCR、Western blot和免疫组化法检测CYP2J2在130例不同类型的人癌组织及相应的癌旁正常组织,4例炎性假瘤组织以及8种常见人源肿瘤细胞系和两种非肿瘤细胞系中的表达情况。结果:CYP2J2在78%(101例)的癌组织中特异性高表达,而癌旁正常组织未能检测到CYP2J2表达,而且CYP2J2 mRNA和蛋白表达水平呈高度的相关性(r=0.613,P<0.01)。同样,免疫组化结果分析发现78%肿瘤组织中有CYP2J2表达,而癌旁正常组织及4例炎性假瘤均阴性。此外还发现CYP2J2主要在肿瘤细胞中表达,而周围的炎性细胞及间质组织均无CYP2J2表达。8种肿瘤细胞中均高表达CYP2J2,而非肿瘤细胞系则无CYP2J2表达。结论:CYP2J2在肿瘤细胞中选择性高表达,CYP2J2可能是肿瘤发生发展的一个标志物。

Background and Objective-Cytochrome P450 arachidonic acid epoxygenase 2J2 （CYP2J2） is a new metabolic pathway of arachidonic acid. However, its biological effects, especially pathophysiologic significance in human beings, remain to be further recognized. This study was to determine the expression of CYP2J2 in human tumor tissues and cell lines. Methods. The expression of CYP2J2 mRNA and protein in 130 specimens of human carcinoma and related adjacent normal tissues, four specimens of inflammatory pseudotumor tissues, eight human tumor cell lines and two normal cell lines （as control） was detected by reverse transcription- polymerase chain reaction （RT-PCR）, Western blot and immunohisto- chemistry. Results： CYP2J2 was highly expressed in 101 （78%） carcinoma tissues, but was not detected in adjacent normal tissues and inflammatory pseudotumor tissues. Its mRNA level was obviously correlated to its protein level（r=0.613, P〈0.01）. Immunohistochemistry analysis showed the same results as RT-PCR and Western blot. Furthermore, CYP2J2 was only expressed in cancer ceils but not in interstitial and inflammatory cells. CYP2J2 was highly expressed in all carcinoma cell lines, but not in two normal cell lines. Conclusion： CYP2J2 is highly and selectively expressed in human tumor tissues and cell lines, and may be a novel biomarker of human tumors.