Rajabpour A, et al. - The correlation between expression of ribonucleotide reductase M1 (RRM1) and cytidine deaminase (CDA) as the resistance genes and their predicted targeting miR-608 in the resistant pancreatic cancer cell lines to gemcitabine were explored. In this study, miR-608 which was targeting RRM1 and CDA was downregulated, during resistance induction in pancreatic cancer cells. It prompted upregulation of these genes.

Methods

• Researchers conducted dual luciferase assay to determine whether both RRM1 and CDA were targeted by miR-608 in 293T and pancreatic cancer cell lines.
• Furthermore, AsPC-1 and MIA PaCa-2 cell lines became gradually resistant to gemcitabine by exposing to the increasing doses of gemcitabine.
• Quantitative PCR examined the expressions of RRM1, CDA and miR-608 in all cell lines, after RNA and miRNAs extraction and cDNA conversion.
• Calcium phosphate method did the pre-miR-608 transfection to the cell lines.
• For analyzing the chemo sensitivity of different cell lines to gemcitabine, MTT assay was performed.

Results

• miR-608 targeted RRM1 and CDA genes in 293T, AsPC-1 and MIA PaCa-2 cell lines were indicated by luciferase assays.
• Resistant MIA PaCa-2 and AsPC-1 cells demonstrated increased expression of RRM1 and CDA than parental cell line, while the expression of miR-608 in resistant MIA PaCa-2 and AsPC-1 cells was lower than parental cells.
• In comparison with scrambled microRNA transfected cells, transfection of MIA PaCa-2 and AsPC-1 cells by miR-608 lead to decreased expression of RRM1 and CDA and lowered viability of the cells.