Topic Highlight
Copyright ©2014 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 28, 2014; 20(44): 16398-16408
Published online Nov 28, 2014. doi: 10.3748/wjg.v20.i44.16398
Recent applications of chemosensitivity tests for colorectal cancer treatment
Yong Sik Yoon, Jin Cheon Kim
Yong Sik Yoon, Jin Cheon Kim, Department of Surgery, University of Ulsan College of Medicine, Seoul 138-736, South Korea
Yong Sik Yoon, Jin Cheon Kim, Institute of Innovative Cancer Research and Asan Institute for Life Sciences, Asan Medical Center, Seoul 138-736, South Korea
Author contributions: Yoon YS designed and wrote the paper; Kim JC designed, wrote and revised the paper.
Supported by Grants from Asan Institute for Life Sciences, No. 2014-69; the National Research Foundation, No. NRF-2013R1A2A1A03070986; Ministry of Science, ICT, and Future Planning, the Korea Health 21 RD Project, No. HI06C0868 and No. HI13C1750; and the Center for Development and Commercialization of Anti-Cancer Therapeutics, No. HI10C2014, Ministry of Health and Welfare, South Korea
Correspondence to: Jin Cheon Kim, MD, PhD, Department of Surgery, University of Ulsan College of Medicine, 88 Olympic-Ro 43-Gil, Songpa-Gu, Seoul 138-736, South Korea. jckim@amc.seoul.kr
Telephone: +82-2-30103499 Fax: +82-2-4749027
Received: May 15, 2014
Revised: July 8, 2014
Accepted: August 13, 2014
Published online: November 28, 2014
Abstract

The evaluation of therapeutic efficacy is necessary to predict the outcome of patients with metastatic colorectal cancer (CRC). In these patients, there is a critical need for predictive chemosensitivity assays and biomarkers to optimize efficacy and minimize toxicity. The introduction of targeted agents has improved the progression-free survival and overall survival of patients with metastatic disease. However, approximately 50% of patients do not show a positive response to chemotherapy and the selection of patients likely to respond to a specific regimen remains challenging. Cell culture-based chemosensitivity tests use autologous viable tumor cells to evaluate susceptibility to specific agents in vitro and predict their direct effects. Adenosine triphosphate-based assays and methyl thiazolyl-diphenyl-tetrazolium bromide-based assays are used widely as sensitivity tests because of their short assay period, technical simplicity, and the requirement of small amount of specimen. Among protein- and gene-based chemosensitivity assays, assessment of KRAS mutation status predicts the response to epidermal growth factor receptor-targeted therapy in CRC patients. The validation of predictive and prognostic markers enables the selection of therapeutic regimens with optimal efficacy and minimal toxicity for each patient, which has been termed personalized treatment. This review summarizes currently available predictive and prognostic chemosensitivity tests for metastatic CRC.

Keywords: Colorectal adenocarcinomas, Colorectal cancer, Chemotherapy, In vitro assays, Molecular targeted therapy, Individualized therapy

Core tip: This review summarizes currently available predictive and prognostic chemosensitivity tests and biomarkers in terms of cell culture, protein, and gene. Cell culture-based chemosensitivity tests are used widely in clinical practice because of their short assay period, technical simplicity, and the requirement of small amount of specimen. Among protein- and gene-based chemosensitivity assays, assessment of KRAS mutation status predicts the response to epidermal growth factor receptor-targeted therapy in colorectal cancer patients.