MicroRNAs and Cancer: Towards a Personalized Medicine

MicroRNAs (miRNAs) are de-regulated in cancer versus the normal tissue counterpart and actively participate in human carcinogenesis. Among the genes whose expression is under their control there are both oncogenes and tumor suppressor genes, revealing that it is not only limiting but simply wrong to assign them a function just as oncogenes or as tumor suppressor genes. In addition to primary tumors, miRNAs can be detected in almost all human body fluids and effectively help to diagnose cancer and to prognosticate clinical outcome and response to treatment of tumors. The advent of miRNA mimic and miRNA silencing molecules has allowed to modulate miRNA expression in tumors, showing that miRNAs can be effectively used as therapeutic agents. This review will focus on those findings that have provided the rationale for the use of miRNAs as patient “tailored” anti-cancer agents.