Flavonoids sensitize tumor cells to radiation: molecular mechanisms and relevance to cancer radiotherapy

Abstract

Purpose: Radiobiological research continues to focus on finding newer strategies for enhanced killing of tumor cells by ionizing radiation. In recent years, chemotherapeutic drugs have been found to possess the capabilities to sensitize tumor cells without affecting the normal cells. There have been increasing research efforts to identify novel and nontoxic compounds which cause minimal or no harm to normal cells but maximize tumor toxicity response to radiation exposure. Extensive researches on flavonoids that are compounds derived from plants have shown that these have promising abilities as radioprotectors and radiosensitizers.

Conclusions: In this review, we examine the role of flavonoids as potential radiosensitizers, review the underlying molecular mechanisms and discuss their potential usefulness in improving cancer radiotherapy. It is emphasized that obtaining a deeper insight into the molecular mechanisms underlying the combined action of flavonoids and ionizing radiation may provide new directions for radiobiological research applicable to the much needed enhanced selective tumor cytotoxicity to treatment agents.

Keywords:

• Cancer
• DNA-damage
• radiation
• radiosensitizer
• flavonoid

Acknowledgments

PT acknowledges the research results of all authors and asks for apology from those whose work could not be cited here due to space limitation. No explicit funding was required for this review.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Prabha Tiwari

Prabha Tiwari obtained her M.Sc. in Biotechnology from Allahabad University and PhD in Life Sciences (Radiation Biology) from Bhabha Atomic Research Center (BARC), Department of Atomic Energy, Mumbai, India. Her research interests involve understanding the biological mechanisms underlying radiation-induced cellular aberrations especially cancer; her research has also focused on inflammation and mucosal immune system and the influence of various dietary nutrients on these processes.

Kaushala Prasad Mishra

Prof. Kaushala Prasad Mishra obtained his M.Sc. from Allahabad University and Ph.D. from Gujarat University. He superannuated as the Head of the Radiation Biology and Health Science Division from Bhabha Atomic Research Center, Department of Atomic Energy, Mumbai, India. His primary research interests are studies on the basic mechanisms in radiation biology and focus of his research is devoted to investigations on the molecular mechanisms of radiation-induced tumor cytotoxicity by radiation and/or chemodrugs applied to improving cancer radiotherapy. He has served on the editorial boards of many reputed peer-reviewed journals and also as a member and chair of various academic and professional bodies such as Indian Science Congress Association, Indian Society for Radiation Biology, Society for Cancer Research and Communication, Society of Biological Chemists, IANCAS; Mumbai, Mutagen Society of India. He is the Founder President of Society of Radiation Research (SRR), India. He has also served as an expert for WHO, IAEA and WONUC among others.