MicroRNAs in Colorectal Cancer: from Diagnosis to Targeted Therapies

Colorectal cancer (CRC) is still one of the five most leading cancer-related death which have one million new cases every year (Pourhoseingholi, 2012; Siegel et al., 2012). Although since mid-1980’s the number of CRCrelated death has been decreasing due to the increased awareness and progresses in screening approaches, the prognosis of patients with metastatic CRC remains unknown (Terzic et al., 2010; Salimzadeh et al., 2012). Eventually, the study for early diagnosis and prognosis markers are still crucial and would allow selecting patients with early CRC stages for operative cancer management and developing novel targeted therapies. The involvements of non-coding RNAs in carcinogenesis and tumor progression have been confirmed by numerous functional studies in the past decades (Seton-Rogers, 2013). Among the all types of ncRNAs, microRNAs (miRNAs) received the greatest attention due to their frequent dys-regulations in CRC. miRNAs compromise a large subsequent of endogenous small ncRNAs that regulate gene expression posttranscriptionally and control various cellular mechanisms including tissue development (Johnston and Hobert, 2003; Zhao et al., 2005), cell proliferation (Cheng et al., 2005; 2006), cell division (Hatfield et al., 2005; Croce