Par-4 Sensitizes Human Colon Cancer Cells to Chemoradiotherapy

Daniel Contract, Heath Mackley, Rosalyn Bryson Irby

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DOI: 10.4236/jct.2011.24074                

Abstract

Despite aggressive treatment and recent advances, cancers of the colon and rectum remain a leading cause of death worldwide. In the case of rectal cancer, chemo-radiotherapy (CRT) is given prior to surgery to provide a greater chance of sphincter sparing surgery and lower the incidence of local recurrence. However, toxicity of CRT remains a problem. The tumor suppressor, Par-4, serves to sensitize tumor cells to chemotherapy and radiation therapy. This study tested the effects of increased Par-4 expression in HT29 human colon cancer cells. The results show the success of Par-4 in sensitizing the tumor cells to both radiation and chemo therapies. In addition, the presence of increased Par-4 caused a positive response to lower doses of both therapies. This supports the idea that Par-4 may be a viable target for gene therapy in cancer treatment, particularly in the case of accessible tumors such as rectal cancers, serving to reduce the required doses of CRT, and consequent side effects, for a successful treatment of rectal cancer.

Keywords

Par-4, Colorectal Cancer, Radiation Therapy, 5-Fluorouracil

Conflicts of Interest

The authors declare no conflicts of interest.

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