CIBP - Centre for Parasite Immunology and Biology, National Institute of Health, Rua Alexandre Herculano, 321, 4000-055 Porto, Portugal.
Int J Parasitol. 2009 Aug;39(10):1083-91. doi: 10.1016/j.ijpara.2009.02.016. Epub 2009 Mar 12.
Schistosome worms are blood-dwelling flukes that cause chronic infection in more than 200 million people and are thought to be responsible for 500,000 deaths annually. During infection with Schistosoma haematobium, eggs are deposited in the mucosa and submucosa of the bladder and lower ureters. Squamous cell carcinoma (SCC) of the bladder is a long-term sequela of chronic infection. The mechanisms underlying the association between S. haematobium and SCC of the bladder are largely unknown, with all reports to date exclusively demonstrating epidemiological evidence linking S. haematobium infection with SCC of the bladder. We hypothesised that the parasite antigens might induce alterations in epithelial cells towards cancer. For this we used Chinese Hamster Ovary (CHO) cells and treated the cells in culture with S. haematobium total antigen (Sh). Our results showed increased proliferation, increased S-phase and decreased apoptosis, as well as down-regulation of tumour suppressor p27 and up-regulation of anti-apoptotic molecule Bcl-2 in Sh-treated cells compared with controls. We also found increased migration and invasion. To our knowledge, this is the first report demonstrating alterations of normal epithelial cells as a direct effect of S. haematobium antigens.
血吸虫是一种寄生在血液中的吸虫，可导致 2 亿多人慢性感染，据认为每年有 50 万人因此死亡。在感染埃及血吸虫期间，虫卵沉积在膀胱和下输尿管的黏膜和黏膜下层。膀胱癌是慢性感染的长期后果。血吸虫与膀胱癌之间的关联的机制在很大程度上尚不清楚，迄今为止所有报告都仅证明了流行病学证据表明埃及血吸虫感染与膀胱癌之间存在关联。我们假设寄生虫抗原可能导致上皮细胞向癌症方向发生改变。为此，我们使用中国仓鼠卵巢 (CHO) 细胞，并在培养的细胞中用埃及血吸虫总抗原 (Sh) 进行处理。结果显示，与对照组相比，Sh 处理的细胞增殖增加、S 期增加和凋亡减少，肿瘤抑制因子 p27 下调，抗凋亡分子 Bcl-2 上调。我们还发现迁移和侵袭增加。据我们所知，这是第一项证明血吸虫抗原直接作用于正常上皮细胞导致其发生改变的报告。
