Cancer and radiation therapy: current advances and future directions

Abstract

In recent years remarkable progress has been made towards the understanding of proposed hallmarks of cancer development and treatment. However with its increasing incidence, the clinical management of cancer continues to be a challenge for the 21st century. Treatment modalities comprise of radiation therapy, surgery, chemotherapy, immunotherapy and hormonal therapy. Radiation therapy remains an important component of cancer treatment with approximately 50% of all cancer patients receiving radiation therapy during their course of illness; it contributes towards 40% of curative treatment for cancer. The main goal of radiation therapy is to deprive cancer cells of their multiplication (cell division) potential. Celebrating a century of advances since Marie Curie won her second Nobel Prize for her research into radium, 2011 has been designated the Year of Radiation therapy in the UK. Over the last 100 years, ongoing advances in the techniques of radiation treatment and progress made in understanding the biology of cancer cell responses to radiation will endeavor to increase the survival and reduce treatment side effects for cancer patients. In this review, principles, application and advances in radiation therapy with their biological end points are discussed.

Keywords: Cancer; Cell death.; Linear energy transfer; Radiation therapy.

Figure 1

The biological target of radiation in the cell is DNA. Extensive damage to cancer cells DNA can lead to cell death. DNA double-strand breaks (DSBs) are more responsible for most cells killing, even a single DSB is sufficient to kill a cell or disturb its genomic integrity by the radiation treatment.

Figure 2

Radiation act directly or indirectly on the cellular DNA.

Figure 3

Types of cell death induced by radiation. Radiation mainly kills the cells either by apoptosis or mitotic catastrophe.