Abstract: It has been reported that more than 20% of malignancies in the developing countries are induced by some infections. However, helminth infections related to malignancies have been less appreciated. Since, helminths sometimes infect their hosts for over decades, the host’s immune responses get modulated Several studies have shown that there are many similarities between the persistence of parasite infection and the progression of tumors in terms of biochemical and immune responses. Thus, this review was designed to evaluate the association between some helminths and tumorigenesis through immunological and biochemical factors. The results of the current study showed that helminth infections could be implicated in the pathogenesis of some cancers. Several factors contribute to tumorigenesis of these helminth-stimulated tumors. These helminth infections increase the proportions of CD19+ B cells and F4/80+ macrophages as well as reduce the proportions of CD8+ lymphocytes, and increase the levels of VEGF, IL-10, and IL-4. In addition, this parasitestimulated inflammation may encourage neoplasia. Also, catechol-estrogens and oxysterols related to some helminths can play a key role in tumorigenesis. Thus, the effects of parasitic helminth infections on the development of tumor are very important. However, the investigation on these issues requires further study, which can be helpful in preventing parasitic helminth infections-related cancers.
