The expression level of miR-29b-2, -155, -197 and -205 was significantly increased in the serum of breast cancer patients. miR-29b-2, -155, -197 and -205 may be useful as a blood-based biomarker for breast cancer screening.
Importantly, both miR-29b/c and miR-200b/c strongly decreased steady state levels of ADAM12-L protein in all breast cancer cell lines tested. miR-29b/c and miR-200b/c also significantly decreased the activity of an ADAM12-L 3'UTR reporter, and this effect was abolished when miR-29b/c and miR-200b/c target sequences were mutated.
Clinically, increased expression of Hsp47 and reduced levels of miR-29b and -29c were associated with poor survival outcomes in breast cancer patients.
The discovery that a GATA3-miR-29b axis regulates the tumour microenvironment and inhibits metastasis opens up possibilities for therapeutic intervention in breast cancer.
We evaluated the impact of miR-29b on global mRNA expression in MCF-7 human breast cancer cells through microarray analysis and further analyzed four genes that were at least twofold down-regulated and predicted as miR-29b targets by at least two of the four widely used miRNA target prediction algorithms.