| BackgroundRecently discovery of tiny microRNAs (miRNAs) has brought about awareness of a new class of regulators of diverse pathways in many physiological and pathological processes, such as tumorigenesis. They modulate gene expression by targeting plethora of mRNAs, mostly reducing the protein yield of a targeted mRNA. With accumulation of information on characteristics of miR-139, complex and in some cases converse roles of miR-139 in tumor initiation, progression and metastasis are emerging.ObjectiveTo explore the expression of miR-139 in colorectal cancer and study its role in colorectal cancer HT29 cells in vitro.Methods1.Surgically-removed colon cancer tissues and paired adjacent normal mucosa tissues were collected from 20 colon cancer patients at the First Affiliated Hospital of Anhui Medical University from April to June 2013.2. Real---time PCR was used to analyze the expression of miR-139 in 20 colorectal cancer (CRC) tissues and their matched adjacent tissues.3.HT29 cells were transfected with a miR-139 mimics, then MTT and softagar method were used to detect the proliferation of the cells.4.The migration and invasion of HT29 cells was investigated using Transwell assay.5.Data are shown as the mean ±s.d. Graphpad Prism software was used for statistical analysis. The two groups paired samples were analyzed by paired t-test and two non-paired samples were analyzed by unpaired t-test.P value <0.05 was considered to be significant.Results1. The expression of miR-139 in colorectal carcinoma tissue and matched normal mucosa tissue were 6.21019E-05±6.08506E-09 and 0.000269444±0.000166458 respectively. The expression of miR-139 was down—regulated in CRC tissues compared with those in adjacent tissues, there were significant differences (t=4.41,P<0.01).2. According to MTT method, from the first day to fifth day, the OD of HT29 cells transfected with miR-139 mimics significantly reduced compared with the control group.3. According to softagar method, NC group counts (41.33333±5.338539) each field compared with miR-139 (72.11111±12.03583) each field (t=8.79, P<0.01).4. According to transwell a ssay, compared with control group, transfection of miR-139 mimics inhibited the migration and invasion of HT29 cells.ConclusionThe expression level of miR-139 was lower in CRC. Transfection of HT29 cells with a miR-139 mimics can inhibit the cell proliferation, migration and invasion in vitro, suggesting that miR-139 is a potent tumor suppressor. |
