Glutamine, cancer, and its therapy

OBJECTIVE: This overview on glutamine, cancer and its therapy discusses some of the in vitro and in vivo work on glutamine and tumor growth, and summarizes animal and human data on the potential benefits of glutamine in the tumor-bearing host receiving radiation or chemotherapy. BACKGROUND: Glutamine is the most abundant amino acid in the body. A tumor can act as a 'glutamine trap,' depleting host glutamine stores and resulting in cachexia. In vitro evidence of the dependence of tumor growth on glutamine has deterred its use in the clinic setting. METHODS: Data from a variety of investigations studying glutamine's interaction with the tumor-bearing host receiving radiation or chemotherapy ware compiled and summarized. RESULTS: A large body of evidence in vivo suggests that supplemental glutamine does not make tumors grow but in fact results in decreased growth through stimulation of the immune system. When given with radiation or chemotherapy glutamine protects the host and actually increases the selectivity of therapy for the tumor. CONCLUSION: Further prospective randomized trials are needed to demonstrate the safety and efficacy in humans undergoing radiation and chemotherapy.