Abstract
PURPOSE: Due to ethnic, genetic and environmental factors, the clinical and molecular characteristics of Turkish colorectal cancer (CRC) patients are different from those of Western populations. The aim of this study was to clarify the relevant alterations of gene expression associated with colorectal carcinogenesis in early-onset patients and to identify specific biomarkers that could provide novel therapeutic molecular targets in this population. METHODS: The expression profiles of 114 different genes were evaluated using mRNA PCR arrays in 39 tumors and 20 surgical margin tissue samples from 39 sporadic CRC patients diagnosed at less than 50 years of age. RESULTS: The expression levels of IMPDH2, CK20, MAP3K8 and EIF5A were strongly up-regulated in CRC tissues compared with normal colorectal tissues (p < 0.05). The highly significant expression ratios of CK20, MAP3K8 and EIF5A observed in the colorectal tumors of patients predicted recurrence (p < 0.05). The expression of IMPDH2, CK20, MAP3K8 and EIF5A was significantly higher in the tumors of patients with short median survival (log-rank p value < 0.05). Progression-free survival was also significantly increased in patients with low expression of the EIF5A gene compared with those who exhibited high expression of this gene (log-rank p value < 0.05). CONCLUSION: We demonstrated that high CK20, MAP3K8 and EIF5A expression levels were significant prognostic factors for poor overall survival in CRC patients. Further studies and validations are required; these genes may provide novel therapeutic molecular targets for CRC treatment, as well as new directions for the development of anticancer drugs.