Roughly 500,000 cancer patients are treated with radiotherapy each year. Acute and late sequelae of radiotherapy have a negative impact upon the quality of life of cancer survivors. These sequelae include proctitis, cystitis, esophageal stricture, cutaneous fibrosis plus others. We propose a novel means of preventing the acute and late radiation injury to normal tissues in these patients. Inhibitors of GSK-32 pathway can serve as radiation protective agents. Lithium can inhibit the GSK-32 pathway. Lithium-containing topical formulations are candidates for being effective radioprotectors by delivering the metal ion to the basal cell layer of epidermis (progenitor cells), preventing radio-induced apoptosis in normal cells in the skin overlying areas of radiation treatment. A total 12 prototype formulations will be screened in a radiation-induced injury porcine model. Six of the formulations will contain lithium succinate and the other six will contain lithium lactate. Two levels of the lithium salts will be screened (1% and 10%), each as an ointment, a gel, and an emulsion (cream). The best formulation(s) will be selected based on induction of proteins that enhance cell viability and inhibition of radiation-induced apoptosis. The efficacy and safety of selected formulations will be optimized in Phase II, supporting proof-of-concept for testing in humans and an IND submission to the FDA.
Over 500,000 cancer patients are treated with radiotherapy each year, and there are presently 10,000,000 cancer survivors in the US. Acute and late sequelae of radiotherapy have a negative impact upon the quality of life of cancer survivors. The goal of this proposal is to attenuate skin injury through development of a topical drug that markedly enhances the viability of the epidermis when administered before irradiation therapy to cancer patients undergoing targeted treatment of deeper tumors with radiation therapy.
