Antitumor effect of whole body hyperthermia with α-galactosylceramide in a subcutaneous tumor model of colon cancer

Aim: Whole body hyperthermia (WBH) has been used clinically as an adjunct to radio- and chemotherapy in patients with various cancers. Recently, it has been reported that an activation of the immune system has recently been reported as a possible contributor to the therapeutic effects of WBH. Conversely, the glycolipid α-galactosylceramide (α-GalCer) is recognized by natural killer (NK) T cells together with the monomorphic MHC-like antigen, CD1d, in mice and humans. This study investigated the antitumor effects of WBH combined with α-GalCer in a mouse subcutaneous tumor model of colon cancer.Methods: Colon26 cells were inoculated subcutaneously into male BALB/c mice to establish subcutaneous tumor. Colon26-bearing mice were treated with WBH using far infrared rays three times/week. Rectal temperature was maintained for 60 min at 41°C. In some experimental groups, α-GalCer was intraperitoneally injected before WBH. We investigated the therapeutic effects of WBH, α-GalCer and combined therapy.Results: (1) ...