[Overexpression of Axin inhibits lymphoma cell invasion and metastasis in vitro by down-regulating β-catenin and MMP7/MMP9].

OBJECTIVE

To investigate that the role of Axin in regulating the invasion and migration ability of lymphoma cells and explore the molecular mechanisms.

METHODS

The expressions of Axin, β-catenin, MMP7, and MMP9 were detected in different lymphoma cell lines by RT-PCR and Western blotting. A lymphoma cell line with low Axin expressions was transiently transfected with pCMV5-HA-Axin and pcDNA5-His-β-catenin plasmid, and the expressions of β-catenin, MMP7, and MMP9 mRNA and protein were observed. A lymphoma cell model stably overexpressing Axin was transfected with AXIN-shRNA and β-catenin-shRNA, and the changes in β-catenin, MMP7, and MMP9 cexpressions were observed. The changes in the invasion and migration abilities of this cell model were assessed following Axin knockdown.

RESULTS

In the lymphoma cell lines tested, the Axin expression showed a negative correlation with β-catenin, MMP7, and MMP9 expressions. In Raji cells with a low Axin expression, overexpression of Axin resulted in decreased expressions of β-catenin, MMP7, and MMP9 at the protein levels but not the mRNA levels, and overexpression of β-catenin obviously increased MMP7 and MMP9 mRNA and protein expressions. In the cells with stable Axin overexpression, Axin knockdown caused increased expressions of β-catenin, MMP7, and MMP9 at the protein levels but not the mRNA levels, while β-catenin knockdown caused lowered expressions of MMP7 and MMP9 and suppressed cell invasion and migration.

CONCLUSION

In lymphoma cells, Axin overexpression can decrease the expression of β-catenin, which in turn decreases the expressions of MMP7 and MMP9 to inhibit the cell invasion and migration.