Clinical implication of microRNAs in molecular pathology.

MicroRNAs are small endogenous noncoding RNAs that are critical regulators of several physiologic and pathologic processes including cancers. Variations in the level of microRNA expression have been linked with the development, progression, and spread of cancer to distant organs. These tiny molecules may play a role in accurate and early diagnosis, and also as prognostic determinants. Modulating their activity provides opportunities for developing and designing novel cancer therapeutics. Recent studies indicate their detection in a wide variety of human biologic specimens including blood, serum, fine-needle aspirates, and tissues, making them clinically useful biomarkers of disease for early detection, prognosis, and for designing personalized therapies.