Cheng Chien-Jui, Wu Yu-Chih, Shu Jye-An, Ling Thai-Yen, Kuo Hung-Chih, Wu Jui-Yu, Chang E E, Chang Shyh-Chern, Huang Yen-Hua
Department of Pathology, Taipei Medical University, Taipei, Taiwan.
J Biomed Sci. 2007 Nov;14(6):797-807. doi: 10.1007/s11373-007-9198-7. Epub 2007 Aug 8.
Testicular germ cell tumors (TGCTs), comprised of seminomas and non-seminomas, are derived from premalignant and noninvasive intracellular germ cell neoplasias. Among TGCTs, seminomas are believed to resemble a transformed state of primordial germ cells (PGCs) and are known to exhibit a gene expression profile similar to that of embryonic stem (ES) cells, such as transcription factor OCT-4. OCT-4 has recently been recognized as a diagnostic marker for clinical aspects of seminomas. However, the role of the OCT-4 protein in seminomas has not been clarified. To determine a possible role of the OCT-4 protein in seminomas, in this paper, we studied a series of 41 testicular tumor tissues and four cell lines by immunohistochemistry, Western blotting, and reverse-transcriptase polymerase chain reaction (RT-PCR) to examine the expression and distribution of the OCT-4 transcription factor in seminomas. By utilizing immunohistochemical staining and Western blotting, we demonstrated that the OCT-4 transcription factor was aberrantly localized in the cytoplasm and nuclei of cells in the collected seminoma tissues. This observation was further confirmed using immunocytochemical staining of NCCIT (seminoma-embryonal carcinoma) and NT2 (embryonal carcinoma) cells. In addition, the RT-PCR results indicated that Oct-4 mRNA was relatively highly expressed in NCCIT, NT2 cells, and seminoma tissues when compared with human embryonic stem cells. The aberrant expression and distribution of the OCT-4 transcription factor in seminomas may provide some important clues concerning the cell transformation between germ line stem cells (like PGC) and testicular germ cell tumors.
睾丸生殖细胞肿瘤(TGCTs)由精原细胞瘤和非精原细胞瘤组成,起源于癌前和非侵袭性的细胞内生殖细胞肿瘤。在TGCTs中,精原细胞瘤被认为类似于原始生殖细胞(PGC)的一种转化状态,并且已知其表现出与胚胎干细胞(ES)相似的基因表达谱,例如转录因子OCT-4。OCT-4最近已被公认为精原细胞瘤临床方面的诊断标志物。然而,OCT-4蛋白在精原细胞瘤中的作用尚未阐明。为了确定OCT-4蛋白在精原细胞瘤中可能的作用,在本文中,我们通过免疫组织化学、蛋白质印迹法和逆转录聚合酶链反应(RT-PCR)研究了一系列41个睾丸肿瘤组织和四种细胞系,以检测OCT-4转录因子在精原细胞瘤中的表达和分布。通过免疫组织化学染色和蛋白质印迹法,我们证明OCT-4转录因子异常定位于收集的精原细胞瘤组织中细胞的细胞质和细胞核中。使用NCCIT(精原细胞瘤-胚胎癌)和NT2(胚胎癌)细胞的免疫细胞化学染色进一步证实了这一观察结果。此外,RT-PCR结果表明,与人类胚胎干细胞相比,Oct-4 mRNA在NCCIT、NT2细胞和精原细胞瘤组织中相对高表达。OCT-4转录因子在精原细胞瘤中的异常表达和分布可能为生殖系干细胞(如PGC)与睾丸生殖细胞肿瘤之间的细胞转化提供一些重要线索。