Title : Promize of herbal drugs in improving cancer radiotherapy
Abstract:
Cancer incidence and mortality have been rapidly increasing in the industrialized world. Discovery of new drugs for cancer treatment has been a challenging task for pharmaceutical companies. Frequently observed problems of general toxicity, exorbitant cost and non-specific action pose profound limitations in treatment of cancer patients. Among the treatment modalities, chemotherapy and radiotherapy account for more than 75 % of patient treatment. A predicament is faced in clinic because drug as well as radiation kill equally both cancer and normal cells of the patients producing undesirable side effects compelling sometimes abandoning of the treatment. Research is, therefore, needed to develop non-toxic and affordable drugs for effective treatment of patients. To meet these objectives, our laboratory has actively been investigating to develop novel drugs from plant kingdom and targeted approaches for selectively killing the cancer cells but sparing the normal cells. Apart from surgery and chemotherapy, the modality of radiotherapy is a often employed mode of cancer patient treatment. While considerable improvement has been made in delivering the radiation to target diseased tissue but technical limitations yet pose many daunting challenges. A developing strategy that holds promise in treatment of cancer patients consists in searching for natural compounds with toxic properties which can selectively enhance tumor cell toxicity to radiation but spare normal cells as desired in clinical settings. Recent research from screening studies have found some potent phytodrugs from plant kingdom which display unique ability to cause no or minimal toxicity to normal cells but remarkably sensitize tumor cells to ionizing radiation. The mechanism involves the radiation generated reactive oxygen species (ROS) which trigger induction of apoptosis (cellular suicide) in tumor cells because of the high oxidative stress status in these cells. This talk is designed to present a brief highlight of developing plant based herbal drugs for improving chemo and radiotherapy of cancer patients. Major part of the talk is based on the recent research results from our laboratory. A few examples of notable herbals such as Triphala, Ellagic acid and Silibinin will be given for the observed increased tumor cytotoxicity in tumor cells by certain compounds from plant sources which hold promise of improving treatment of cancer patients in radiotherapy.
