Carcinogenesis associated with parasites other than Schistosoma, Opisthorchis and Clonorchis: A systematic review

Abstract

Only three helminths (Schistosoma haematobium, Opisthorchis viverrini and Clonorchis sinensis) are directly associated with carcinogenesis in humans whereas the role of other parasites in cancer remains unclear. This study aimed to perform a systematic review to identify recent insights in the role of other parasite infections in carcinogenesis. We conducted systematic searches of MEDLINE and EMBASE on July 2015. Our primary outcome was the association between parasitic infections and carcinogenesis. Out of 1,266 studies, 19 were selected for detailed evaluation (eight for helminths and 11 for protozoa). The mechanisms of helminth-induced cancer included chronic inflammation, sustained proliferation, modulation of the host immune system, reprogramming of glucose metabolism and redox signaling, induction of genomic instability and destabilization of suppressor tumor proteins, stimulation of angiogenesis, resisting cell death, and activation of invasion and metastasis. In addition to the current knowledge, the following parasites were found in cancers or tumors: Echinococcus, Strongyloides, Fasciola, Heterakis, Platynosomum and Trichuris. Additional parasites were found in this systematic review that could potentially be associated with cancers or tumors but further evidence is needed to elaborate a cause-effect relationship.

The ovarian cancer oncobiome

“…This correlates with our earlier study where Trichuris was detected in 96% of triple negative breast cancer samples [6]. There have been other reports which demonstrated an association of Trichuris with cancer [43, 44]. Epithelial dysregulation and hyper proliferation during chronic infection of Trichuris [45] has also been reported, which potentially could promote tumorigenesis.…”

“…Epithelial dysregulation and hyper proliferation during chronic infection of Trichuris [45] has also been reported, which potentially could promote tumorigenesis. The association of other parasites like Echinococcus, Strongyloides , Trichinella , Schistosoma, Leishmania , Ascaris , Trichomonas to cancer was not unique to our study, and has been previously reported [44, 46–50]. …”

Angiogenesis in Schistosoma haematobium‐associated urinary bladder cancer

“…These patients had significantly high VEGF levels compared with healthy people . Therefore, this angiogenic capacity has been suggested as an early marker of preneoplastic and neoplastic lesions in schistosomiasis associated SCC . Several growth factors and other molecules produced by the schistosome itself have been reported to be associated with tumor growth, progression and survival of urinary bladder cancer.…”

Parasite Infection, Carcinogenesis and Human Malignancy

“…Intriguingly, Trypanosoma cruzi , the etiological agents of Chagas disease, displays apparently paradoxical roles in malignancy in exerting carcinogenic and anticancer properties (Krementsov, 2009, Sacerdote de et al, 1980). Potential causative roles of other parasitic infections have been postulated (Machicado and Marcos, 2016). …”