Abstract:

Objective

To study the regulation effect of miR-21 ASO on proliferation and apoptosis of Tongue squamous cell carcinoma （TSCC） cell lines.

Methods

TSCC cell lines：SCC-15 and CAL27 were cultured in vitro and their miR-21 expressions change were determined by transfection of miR-21 ASO.Luciferase reporter assay was used to evaluate the function of miR-21 ASO.The cell proliferation following transfection was evaluated by MTT assay and colony formation experiment.The cell apoptosis following transfection was a nalyzed by Annexin V analysis and Cytochrome C release experiment.

Results

MiR-21 was up-regulated highly 14-fold in SCC-15 and CAL27 cell lines relative to the normal tongue squamous cell （NTSC）（P=0.037，0.015）， but after transfected with miR-21 ASO， miR-21 expression in the cell lines was knocked down significantly （P=0.017， 0.006）， meanwhile the inhibition of luciferase activity by miR-21 reduced from 50% to 20% （P=0.002， 0.003）.MTT assay revealed that viability of SCC-15 cells reduced from 86% to 45% （P=0.002） after transfection with miR-21 ASO， while that of CAL27 cells decreased from 83% to 39% （P=0.004）.Colony formation of both cell lines decreased highly after transfected with miR-21 ASO （P=0.007， 0.032）.Annexin V assay showed that transfection with miR-21 ASO promoted apoptosis greatly.The percent of apoptotic cells increased 27 folds for SCC-15 cells and 17 folds for CAL27 cells.Similarly， miR-21 ASO transfected cells displayed Cytochrom C release.

Conclusions

MiR-21 function can be antagonized effectively by miR-21 ASO.The specificity and effectiveness of miR-21 ASO in antagonizing miR-21 function hold great promise for the development of therapeutic strategies based on miR-21 inhibition.

Key words: Tongue squamous cell carcinoma, MiR-21, Antisense oligonucleotide（ASO）, Proliferation, Apoptosis