Jeon Byung-Suk, Yoon Byung-Il
Laboratory of Histology and Molecular Pathogenesis, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon 200-701, Republic of Korea.
ScientificWorldJournal. 2012;2012:385840. doi: 10.1100/2012/385840. Epub 2012 Apr 30.
Bcl-2 is an intracytoplasmic and membrane-associated apoptosis suppressor, and its overexpression is closely associated with survival of malignant tumors, in particular their aggressive behavior and poor prognosis. The role of Bcl-2 is, however, still controversial in cholangiocarcinogenesis because of the discrepancies in the expression of the protein. In the present study, alteration in the expression of Bcl-2 in cholangiocarcinogenesis was investigated by studying the immunoreactivities of this protein in normal, hyperplastic bile ducts with or without dysplastic changes, and neoplastic bile duct cells from a hamster cholangiocarcinoma (ChC) model. Cytoplasmic staining, which reflects high-Bcl-2 immunoreactivity, was negative to very weak in normal and hyperplastic bile ducts without dysplastic changes, while hyperplastic bile ducts with dysplasia indicated heterogeneously strong expression. On the other hand, most of the neoplastic cells of invasive cholangiocarcinomas were negative to weak as much as the level of normal bile ducts. The results suggest that the antiapoptotic factor Bcl-2 plays a limited role in the survival of highly proliferative, potentially dysplastic bile duct cells. However, the role of Bcl-2 in biliary cancer cells was not significant.
Bcl-2是一种胞质内且与膜相关的凋亡抑制因子，其过表达与恶性肿瘤的存活密切相关，尤其是与肿瘤的侵袭性行为和不良预后相关。然而，由于该蛋白表达存在差异，Bcl-2在胆管癌发生中的作用仍存在争议。在本研究中，通过研究正常、增生性胆管（有或无发育异常改变）以及来自仓鼠胆管癌（ChC）模型的肿瘤性胆管细胞中该蛋白的免疫反应性，来研究胆管癌发生过程中Bcl-2表达的变化。反映高Bcl-2免疫反应性的细胞质染色在无发育异常改变的正常和增生性胆管中为阴性至极弱，而有发育异常的增生性胆管则显示出异质性强表达。另一方面，浸润性胆管癌的大多数肿瘤细胞与正常胆管水平一样为阴性至弱阳性。结果表明，抗凋亡因子Bcl-2在高度增殖、潜在发育异常的胆管细胞存活中起有限作用。然而，Bcl-2在胆管癌细胞中的作用并不显著。
