Mycoviruses in Fungi: Carcinogenesis of Fungal Agents May Not Always Be Mycotoxin Related

Certain viruses have been found to induce diverse biological pathways to carcinogenesis, evidenced by the presence of viral gene products in some tumors. Despite the fact that many fungal agents contain mycoviruses, until recently, their possible direct effects on human health, including carcinogenesis and leukemogenesis, had not been explored. In this regard, most studies of fungal agents have rightly concentrated on their mycotoxin formation and effects. Recently, the direct role of yeasts and fungi in the etiology of cancers, including leukemia, have been investigated. While greater attention has been placed on the carcinogenic effects of Candida, the role of filamentous fungi in carcinogenesis has also been explored. Recent findings from studies using the enzyme-linked immunosorbent assay (ELISA) technique indicate that the plasma of patients with acute lymphoblastic leukemia (ALL) uniformly contains antibodies for a certain mycovirus-containing Aspergillus flavus, while controls are negative. The exposure of mononuclear leukocytes from patients with ALL in full remission, and long-term survivors, to the product of this organism was reported to result in the re-development of typical genetics and cell surface phenotypes characteristic of active ALL. Mycoviruses are known to be able to significantly alter the biological characteristics and functions of their host. The possible carcinogenic and leukemogenic role of mycoviruses, with and without their host, needs to be further investigated.

Automated summary

Certain viruses have been found to induce carcinogenesis through diverse biological pathways, with viral gene products present in tumors. While the presence of mycoviruses in fungal agents has been known, their direct effects on human health, including carcinogenesis and leukemogenesis, have only recently been explored. Studies have investigated the role of yeasts and fungi, including filamentous fungi, in cancer development, with attention focused on the carcinogenic effects of Candida. Recent findings using the enzyme-linked immunosorbent assay (ELISA) technique revealed that patients with acute lymphoblastic leukemia (ALL) consistently have antibodies for a specific mycovirus-containing Aspergillus flavus in their plasma, while controls do not. Exposure to this organism's product resulted in the re-development of active ALL characteristics in mononuclear leukocytes from ALL patients in remission and long-term survivors. The potential role of mycoviruses, with and without their host, in carcinogenesis and leukemogenesis needs further investigation.