Evaluation of miR-107, DAPK1, and KLF4 Expression in Colorectal Tumors and Effect of Oxaliplatin and 5-FU on their Levels in Colorectal Cancer Cell Lines

Abstract

Background: In recent years, the role of micro-RNAs in the cancer pathophysiology has attracted a great deal of scientific attention. MiRNAs regulate a variety of cellular functions, such as apoptosis, differentiation and migration by targeting oncogenic or tumor suppressor genes. We conducted the current study to assess the expression of miR-107, Krüppel-like factor 4 (KLF4) and death-associated protein kinase (DAPK1) genes in malignant and normal colon tissues and also colorectal cancer (CRC) model cells exposed to oxaliplatin and 5-FU chemotherapy agents. Method: In this case-control study, the tissue samples from CRC patients were collected during colonoscopy process in 2013 -2016 at Imam Reza hospital. Subsequently, the expression levels of miR-107, KLF4, and DAPK1 were detected with quantitative Real-Time PCR. Furthermore, in the in vitro phase of this study, we investigated the changes in the expression level of miR-107, KLF4 and DAPK1 transcripts after oxaliplatin and 5-FU treatment. Results: Unlike miR-107, the expression levels of KLF4 and DAPK1 genes decreased in the tumor samples compared to those in the marginal specimens. In addition, both oxaliplatin and 5-FU significantly increased the expression level of miR-107. There were significant correlations between the expression levels of miR-107, KLF4, and DAPK1genes and clinicopathological features, for instance lymph node metastasis and cell differentiation. Conclusion: The current study suggested a tumor suppressor role for KLF4 and DAPK1 in CRC. The altered expression of miR-107, KLF-4, and DAPK1 genes in CRC tumors and healthy tissues could be utilized for CRC diagnosis and prognosis. Furthermore, the studied genes could be considered as potential therapeutic targets in CRC.

Keywords

• colorectal neoplasms
• mir-107
• klf4
• dapk1
• oxaliplatin
• 5-fu