寄生虫感染与癌症

寄生虫感染和癌症关系复杂,具有促癌和抑癌两方面的作用。感染埃及血吸虫、麝后睾吸虫、华支睾吸虫等具有明确的致癌和促癌作用,这类蠕虫在宿主体内可能通过物理损伤引起细胞增生和分化、通过慢性病理性炎症激活信号转导通路、通过寄生虫来源的排泄和分泌产物引起代谢性氧化应激损伤,影响宿主细胞的基因组稳定性,引起细胞的分化和恶变,最终诱导宿主癌症的发生。而恶性疟原虫、克氏锥虫、弓形虫等寄生虫感染具有抑癌作用,主要表现为诱导宿主产生抗肿瘤免疫反应、抑制肿瘤新生血管生成及抑制肿瘤的侵袭和转移,部分针对应用寄生虫相关生物因子治疗癌症的研究已经取得一定的进展。本文综述寄生虫感染与癌症之间的复杂关系以及两者相互作用的机制。

Parasitic infections and cancer

Objective Parasitic infections have a complicated relationship with cancers, including both cancer-promoting and anti-cancer effects. Schistosoma japonicum, Opisthorchis viverrini,Clonorchis sinensis has a clear cancer-promoting effect. Infections with these types of helminths may cause cellular transformation and proliferation by physical damages, activating signaling pathways due to chronic inflammation and induce metabolic oxidative stress by parasites-derived products, which could lead to genomic stability of host cells, cell differentiation and malignant transformation, and ultimately the occurrence of cancer. While infection with parasites such as Plasmodium falciparum, Trypanoma cruzi, and Toxoplasma gondii may have a anti-tumor effect, through inducing anti-tumor immune response, or inhibiting tumor angiogenesis, tumor invasion and metastasis. Some research progress has been made in identification of the parasite-derived biological factors for therapeutic potential of cancers. This article reviews the relationship between parasitic infections and cancers, and its mechanisms.