MicroRNA-552 in colorectal cancer with poor prognosis. Its role as a novel molecular biomarker

Amongst the biomolecules currently used for laboratory diagnosis in colorectal cancer (CRC),1,2 many have been shown to be insufficient for predicting prognosis in the critical stages of the disease. This is still the case today, even though significant advances have been made in early diagnosis and therapeutic strategies, e.g. with extensive SNP analysis in oncogenes. CRC still draws great attention worldwide because of its high incidence rate and mortality. At the moment, specific and selective diagnosis by optimal molecular biomarkers is of utmost necessity in patients with poor prognosis, because of the extremely low therapeutic potential and the need for a fast response for a possible individualized target therapy2. Over the last decade, micro-RNA functions study have changed our understanding of cells and diseases with a particular emphasis on cancer biology. For this reason, several miRNAs are currently being intensively studied and proposed as promising candidates in cancer therapy and/or as biomarkers to reveal disease progression and prognosis1. The use of miRNAs in cancer diagnosis could offer several advantages1. First of all, the non-invasive nature of miRNAbased assays, together with their sensitivity, selectivity, and specificity in detecting cancers. Furthermore, another positive point for proposing these biomolecules as interesting molecular targets is due to the fact that they use easy and less expensive tools, such as the Real-time quantitative PCR, to detect genic expression levels3-9. In this context, the paper by Wang et al10, describing miRNA-552 on CRC, is particularly interesting. The authors noted the possibility of using miR-552 as biomarker in CRC with poor prognosis. In fact, as already showed by Cao et al11, miR-552 promotes tumor cell proliferation and migration. Furthermore, it was detected in high levels in advanced forms of CRC.