Dysregulation of miR-27a and SMAD2 can be a reliable indicator in the prognosis and diagnosis of CRC as well as in response to chemotherapy drugs

Abstract

PurposeColorectal cancer is one of the most common cancers in the world in terms of prevalence. Oxaliplatin and 5-fluorouracil are two important chemotherapy drugs used primarily to treat gastrointestinal cancers. miR-27a, SMAD2, and SGPP1 are three genes that have been shown to play a role in the progression of various cancers. MethodsForty samples from patients with colorectal cancer and adjacent non-tumor tissues were collected and evaluated by real-time PCR to assess the expression levels of miR-27a, SMAD2, and SGPP1. Thus, the relative expression of the considered genes in two cell lines including LS180 and SW480 in response to IC50 doses of 5-FU and oxaliplatin was investigated. In addition, the relationship between target genes and clinicopathological characteristics of patients was investigated. ResultsThe expression levels of miR-27a and SMAD2 were shown to be significantly dysregulated in colorectal cancer cell lines compared to adjacent non-cancerous cells, but SGPP1 showed no change. Also, it was found that the expression of none of the three genes except miR-27a did not change in response to the IC50 dose of drugs. There was also no significant relationship between SGPP1 and pathologic characteristics of the patients, but both miR-27a and SMAD2 were associated with some features, such as tumor stage and lymph node metastasis. ConclusionsOur findings suggest that altered expression levels of miR-27a and SMAD2 may be used as new diagnostic and prognostic biomarkers in the evaluation of patients with CRC. In addition, miR-27a has a significant reduction in response to chemotherapeutic agents. Thus, both miR-27a and SMAD2 can be used as a marker to determine the clinical outcome of patients with colon cancer, and also miR-27a may be used as a therapeutic target.