探討OTEX基因和前列腺癌的關係

Abstract

中文摘要 OTEX基因位在人類之X染色體， 在睪丸， 副睪， 前列腺，卵巢和大腦中均有表現。 我們之前由多次小鼠的GenBank資料庫的搜尋及cDNA基因庫之篩選都沒有找到小鼠對等之ortholog gene， Zoo blot 分析顯示OTEX可能只存在於人類基因組中， 因而推斷OTEX是一個在演化後期才出現的基因， 可能在人類生理上扮演一個其他物種所不具備的角色。 我們的分析發現OTEX也表現在LNCaP前列腺癌細胞， 並且於受到雄性激素之後表現顯著增加。 我們懷疑OTEX之表現與前列腺癌有相關性， 於是， 我們利用Real-time PCR分析BPH和PCa病人前列腺OTEX和PSA的表現量。 我們研究室之前以Promoter scan搜尋與OTEX gene上游和intron 1的區域時， 在上游大約1 kb的地方發現有雄性素受器結合區域， 因此，我們藉由Reporter assay研究OTEX是否直接受雄性激素的影響。 此外， 我們也藉由將OTEX基因轉殖入PC3 cell(非雄性素 依賴性之細胞)中， 以探討細胞在OTEX表現下， 生長速度、型態及分化情形之改變， 藉以了解OTEX可能所扮演之角色， 綜合以上之研究， 應該可以協助我們對OTEX基因與前列腺癌關係更加了解。English Abstract OTEX gene is localized on the human X chromosome and expressed in testis, epididymis, prostate, ovary and brain. No ortholog of OTEX gene has been identified in mouse genome through intensive GenBank search and cDNA library screening. Zoo blot analysis reveals that OTEX is only present in human genome which suggests that OTEX appeared in a later period during evolution, and may be involved in an important genetic regulation of the complicated human physiology. OTEX expression was also identified in LNCaP prostate cancer (PCa) cell line, and the expression was stimulated dramatically following androgen treatment. Real-time PCR analysis was thus used to quantitate the expression levels of OTEX and PSA in BPH and PCa patients. OTEX gene was transfected into PCa cell line, PC3, to further uncover the functional significance of OTEX. An inducible cell line is established and used to investigate the influence of the physiologic significance of OTEX gene on PC3 cell line. Promoter scan was used to search binding motif of upstream and intron 1 of OTEX gene, and an putative androgen response element (ARE) site was identified in the upstream about 1 kb region. To test whether OTEX is under the regulation of androgen directly, OTEX promoters with or without the putative ARE were analyzed by reporter assay. Results obtained from these studies should help in uncovering the correlation between OTEX gene and PCa.