A study conducted by the Osaka University Graduate School of Medicine sought to evaluate the safety and effectiveness of a mushroom product, active hexose correlated compound (AHCC), on chemotherapy-induced adverse effects and quality of life (QOL) in patients with cancer.
Interestingly, the DNA levels of HHV-6 were significantly increased after chemotherapy course. However, the administration of AHCC significantly decreased the levels of HHV-6 in saliva during chemotherapy from a mean value of 1083 to 254 copies/ ml (P<0.05). During the course of chemotherapy, 24 patients were evaluated weekly for adverse effects and QOL via a blood test, EORTC QLQ-C30 questionnaire, and DNA levels of HHV-6 in saliva. The drop in HHV-6 saliva viral load correlated with improved QOL scores in the EORTC QLQ-C30 questionnaire, as well as decreased hematotoxicity and hepatotoxicity. These findings suggest that salivary HHV-6 levels may be a good biomarker of QOL in patients during the course of chemotherapy
AHCC is extracted from the mycelium of Basidiomycetes mushrooms and was developed by investigators at Tokyo University in collaboration with a commercial company, Amino Up Chemical Co, Ltd (Sapporo, Japan) in 1989, and the supplement is widely used in Japan to enhance immune response and reduce side effects during cancer treatment (Hangai 2013). In mice, AHCC delays tumor development and increases the activation and proliferation of CD4+ and CD8+ cells as well as tumor specific IFN-gamma producing CD8+ cells (Gao 2006). The supplement has been shown to have anti-oxidant (Ye 2003), anti-inflammatory (Daddaoua 2007), and antimicrobial (Aviles 2003) and anti-tumor effects (Matsushita 1998).
The authors speculated that HHV-6 would be a good biomarker for chemotherapy related fatigue, partly based on previous links to chronic fatigue syndrome and their own observation that detectable saliva HHV-6 DNA in office workers was higher right before major holiday break (80%) than right after a one week break (23%).
The authors note that AHCC has been shown to inhibit leukopenia, neutropenia and thrombocytopenia, and also protects liver function. All of these conditions have been linked to HHV-6 reactivation.
Why does HHV-6 reactivate during chemotherapy?
The authors explain that this remains unclear but point to an unknown immune suppressive mechanism. One hypothesis that has been put forward recently is that by Steven Zeichner and associates at Children’s National Medical Center, who proposed that apoptosis can activate herpesviruses (Prasad 2013). Zeichner specifically cites highly toxic chemotherapy drugs as a potential cause of herpesvirus reactivation in these patients.
For more information, read the full paper.