Abstract
BACKGROUND: The prevalence of colorectal cancer (CRC) has been increasing in the world. There are different factors for colorectal cancer, and changes in the levels of gene expression such as miR-145-5p, DANCR and NRAS can be one of the factors. METHODS: The case-control study was performed on 40 CRC specimens and 40 adjacent healthy tissues. Fresh tumor and tumor-free adjacent tissue samples were obtained from patients who underwent the surgical operation as a conventional treatment procedure. After tumor resection, the specimens were immediately frozen in liquid nitrogen and stored at -80°C until further investigation. Cox regression was used to get the hazard ratios. RESULTS: The mean ± SD age of the patients was 62.45± 12.89 years. Of these, 62.5% were males. The risk of death from CRC in patients with low miR-145-5p levels is about 10 times higher than the high expression levels (HR = 10.759, P = 0.009). High expression levels of NRAS can increase the risk of CRC death up to 4 times (HR = 4.12, P = 0.045). The study did not show a relationship between DANCR expression levels and death risk from CRC (HR = 1.582, P = 0.439). CONCLUSION: These expression levels revealed that miRNA-145-5p and NRAS can be utilized as diagnostic biomarkers in colorectal cancer death. This may also introduce the microRNAs as colorectal cancer therapeutic targets.