Correlation of microrna-372 upregulation with poor prognosis in human glioma

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1707761328850011 webciteHuman gliomas are a heterogeneous group of primary intracranial tumors for both children and adults [1]. The entities are distinguished based on morphological criteria by histological analysis and presumed cell of origin. According to the World Health Organization (WHO) classification which is based on histomorphological criteria, human gliomas includes well-differentiated low grade astrocytomas [World Health Organization (WHO) grade I~II], anaplastic astrocytomas (WHO grade III) and glioblastoma multiforme (GBM, WHO grade IV) [2]. Despite great progress in therapeutic technologies, such as surgery, radiotherapy, photodynamic therapy, and chemotherapy, the clinical outcome of patients with gliomas remains poor, with a lower than 3% 5-year survival rate for patients with GBM [3]. Although the WHO classification can reflect the anticipated malignancy of the tumor and serve as a criterion to predict the clinical outcome of patients, recent studies have indicated that histomorphological criteria alone may not be sufficient to estimate the prognosis [2,4-8]. For example, Curran et al. [9] demonstrated that the median survival time of patients with high-grade gliomas range from 5 to 59 months and some patients with low-grade tumors also present poor outcome. Therefore, to investigate the molecular genetics of gliomas may help to overcome some of these limitations.MicroRNAs (miRNAs) are a recently discovered class of short non-coding endogenous RNA molecules that have a wide impact on the regulation of multiple target genes’ expression post-transcriptionally [10]. At first, miRNAs are transcribed by RNA polymerase II to yield long transcripts known as pri-miRNAs, which are processed to pre-miRNAs by the RNase III enzyme Drosha in the nucleus; then, the pre-miRNAs are exported to the cytoplasm by exportin-5 and subsequently converted to mature duple