Involvement of micro RNAs (miRNA) is currently the focus for cancer studies as they effect the post transcriptional expression of different genes. Let-7 family is among the firstly discovered miRNAs that play important role in cell proliferation and dysregulation leading to cell based diseases including cancer. Another family, miRNA-200 prevents transformation of cell to malignant form and tumor formation by interacting with epidermal mesenchymal transition (EMT). Similarly miRNA-125 controls apoptosis and proliferation by affecting multiple genes involved in transcription, immunological defense, resistance against viral and bacterial infections that ultimately leads to cell proliferation, metastasis and finally cancer. All of these micro RNAs are known to be either upregulated or downregulated in various cancers. Current review is focused to elaborate the role of these three families of micro RNAs on different genes that ultimately cause cancer. In conclusion we can say that the miRNAs discussed here are mostly downregulated in various cancers with some exceptions when upregulation of miRNA-125 may be attributed to cancer formation.
Keywords: Cancer; miRNA-125; miRNA-200; miRNA-let7; microRNAs.