www.impactjournals.com/oncotarget/ Oncotarget, Vol. 6, No. 28 Characterization of SLC22A18 as a tumor suppressor and novel biomarker in colorectal cancer Yeonjoo Jung1,2,*, Yukyung Jun1,2,*, Hee-Young Lee1,2, Suyeon Kim1,2, Yeonhwa Jung1,2, Juhee Keum1,2, Yeo Song Lee3, Yong Beom Cho4, Sanghyuk Lee1,2 and Jaesang Kim1,2 1 Ewha Research Center for Systems Biology, Seoul, Korea 2 Department of Life Science, Ewha Womans University, Seoul, Korea 3 Samsung Biomedical Research Institute, Seoul, Korea 4 Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea * Y. Jung and Y. Jun contributed equally to this work Correspondence to: Jaesang Kim, email:
[email protected] Keywords: SLC22A18, tumor suppressor, colorectal cancer, G2/M arrest, KRAS Received: November 26, 2014 Accepted: June 18, 2015 Published: June 28, 2015 This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. ABSTRACT SLC22A18, solute carrier family 22, member 18, has been proposed to function as a tumor suppressor based on its chromosomal location at 11p15.5, mutations and aberrant splicing in several types of cancer and down-regulation in glioblastoma. In this study, we sought to demonstrate the significance of SLC22A18 as a tumor suppressor in colorectal cancer (CRC) and provide mechanistic bases for its function. We first showed that the expression of SLC22A18 is significantly down-regulated in tumor tissues using matched normal-tumor samples from CRC patients. This finding was also supported by publically accessible data from The Cancer Genome Atlas (TCGA).