The role of miRNAs targeting K-ras and APC genes in colorectal cancer

Abstract

OBJECTIVES: The occurrence of abnormal expression patterns in different types of cancer suggests that micro RNAs (miRNAs) may play an important role in tumorigenesis. The aim of this study was to examine the expression levels of miRNAs known to be associated with the regulation of the expression levels of the APC and K-ras, which are important in the development of colorectal cancer (CRC). METHODS: The expression levels of miR-27, miR-663, miR-217, miR-181d, APC and K-ras in the serum, tumor and adjacent tumor-free (healthy) tissues of the patients and serum of the healthy controls were investigated with qRT-PCR. RESULTS: Expression levels of miR-217, mR-181d, miR-663, miR-27 and K-ras were found to be higher in CRC tissues than in adjacent tumor-free tissues of the patients. In patient serum samples, miR-663 levels were statistically more elevated than in controls. In patient tumor tissues, miR-217, miR-181d and miR-27 expressions were found to be higher. CONCLUSIONS: Increased miR-181d and miR-217 expression levels are associated with increased K-ras expression in the tumor tissues, and the expression of K-ras, which takes part as an oncogene in the CRC development, might be regulated by these miRNAs (Tab. 4, Ref. 33).

Analysis of Efficacy, Safety, and Prognostic Factors of mFOLFOX6 Regimen Combined with Cetuximab and Simvastatin in the Treatment of K-RAS Mutant Colorectal Cancer

“…K-RAS mutations occur on exons 2, 3, and 4, and exon 2 is a common mutation site for K-RAS mutations. The mutation of K-RAS gene is a common oncogene in CRC, and the incidence of mutation in Asians is 29–62.9% [ 23 , 24 ]. Various genes, such as EGFR and K-RAS, are involved in the occurrence of CRC.…”

Lower expression of KAI1 as a biomarker of poor survival prognosis of melanoma combined with colorectal cancer metastasis

“…MiR-663 is reportedly involved in many important pathological processes, especially in cancer. 20 MiR-663 plays an important regulatory role in ovarian cancer and can promote disease progression by targeting TUSC2. 19 MiR-663 has been reported to affect apoptosis by controlling mitochondrial outer membrane permeability (MOMP) by directly targeting PUMA/BBC3 and BTG2 in non-small cell lung cancer (NSCLC) and acts as an oncogene in this disease.…”

Promotion or remission: a role of noncoding RNAs in colorectal cancer resistance to anti-EGFR therapy

“…There is a regulatory feedback: miR-181d regulates the secretion of KLK6, and its expression decreases when KLK6 is knocked down [80]. However, miR-181d was also found to be upregulated in CRC and involved in the post-transcriptional regulation of c-MYC by targeting FBXL3 and CRY2, as well as in the regulation of KRAS expression [82][83][84][85]. One of these studies identified miR-181d as possibly a onco-miRNA in CRC, which seems to be contrary to the above studies [82].…”