Application of Kampo medicines for the palliation of cancer cachexia

Cancer cachexia results in the discontinuation of aggressive cancer therapy, and halting its progression has a significant effect on the survival rate and quality of life of patients with cancer. Currently, there are few therapies to control or slow down the progression of cancer cachexia. Although traditional Japanese Kampo medicine is widely used to support aggressive cancer therapy, the relevant scientific evidence is limited. Additionally, Kampo medicines are based on historical experience. In recent years, there have been widespread attempts to prove the efficacy of Kampo medicines through basic research, and an increasing number of studies have clarified the mechanism of action of Kampo medicines at the molecular level. It has been proposed that the improvement of cancer cachexia by Kampo medicines might involve enhancement of feeding via the central nervous system, improvement of protein maintenance in the skeletal muscle, and suppression of inflammatory cytokine production. In particular, among Kampo medicines, tonifying formulae, called "hozai" in Japanese, have been shown to be effective in alleviating cancer cachexia. In this review, we summarize the recent progress of basic and clinical research in Kampo medicines on cancer cachexia, and introduce Kampo medicines that are expected to be attractive supportive cancer medication.