Fine-tuning miR-21 expression and inhibition of EMT in breast cancer cells using aromatic-neomycin derivatives

Micro RNAs are a class of endogenously expressed non coding RNAs that negatively regulate gene expression within cells and participate in maintaining cellular homeostasis. By targeting 3prime UTRs of target genes, individual miRs are able to control a wide array of gene expression. Previous research has shed light upon the fact that aberrantly expressed miRs within cells can pertain to diseased conditions like cancer. Malignancies caused due to miRs are because of high expression of onco miRs or feeble expression of tumour suppressing miRs. Studies have also shown miRs to engage in epithelial to mesenchymal transition that allows cancer cells to become more invasive in nature and metastasise. miR21 is an onco miR highly expressed in breast cancer cells and targets protein PTEN which abrogates EMT. Therefore, we discuss an approach where in house developed peptidic amino-sugar molecules have been used to target pre miR 21 to inhibit miR21 biogenesis, and hence antagonize its tumour causing effect and revert EMT. Our study shows that small molecule based fine tuning of miR expression can cause genotypic as well as phenotypic changes and also establishes the potential and importance of nucleic acid therapeutics.