miR-219-1-3p is a negative regulator of the mucin MUC4 expression and is a tumor suppressor in pancreatic cancer

Advances in miRNA-Mediated Mucin Regulation

MicroRNAs (miRNAs) are an important class of small non-coding RNAs that direct post-transcriptional gene regulation by different mechanisms. Mounting evidences from numerous studies in the last decade have unraveled that deregulated miRNAs, and their cognate target expressions are strongly implicated in the carcinogenesis. Recent advances have highlighted miRNA-mediated regulation of mucins that have critical role in inflammation and cancer biology. The aberrant expression and differential glycosylation of mucins cause tumorigenesis, metastasis, chemoresistance and poor outcome of cancer patients, thus recognizing them as attractive therapeutic targets. Though current mucin-based therapies (antibodies, vaccines, immunotherapy, peptide inhibitors) have shown preclinical utility but only a handful promise for clinical transferability. In this context, understanding miRNA-mediated modulation of multiple mucin(s) expression and function gives a new hope for future anti-tumor therapeutics. Herein, we reviewed miRNA biogenesis, mechanism of action, and their role in tumor development. Further, we provide an overview of miRNA-mediated mucin regulation and their application as anticancer therapeutics.

miRNAs in pancreatic cancer: therapeutic potential, delivery challenges and strategies

Pancreatic ductal adenocarcinoma (PDAC) is a severe pancreatic malignancy and is predicted to victimize 1.5% of men and women during their lifetime (Cancer statistics: SEER stat fact sheet, National Cancer Institute, 2014). miRNAs have emerged as a promising prognostic, diagnostic and therapeutic tool to fight against pancreatic cancer. miRNAs could modulate gene expression by imperfect base-pairing with target mRNA and hence provide means to fine-tune multiple genes simultaneously and alter various signaling pathways associated with the disease. This exceptional miRNA feature has provided a paradigm shift from the conventional one drug one target concept to one drug multiple target theory. However, in vivo miRNA delivery is not fully realized due to challenges posed by this special class of therapeutic molecules, which involves thorough understanding of the biogenesis and physicochemical properties of miRNA and delivery carriers along with the pathophysiology of the PDAC. This review highlights the delivery strategies of miRNA modulators (mimic/inhibitor) in cancer with special emphasis on PDAC since successful delivery of miRNA in vivo constitutes the major challenge in clinical translation of this promising class of therapeutics.