PURPOSE: Astrocytomas are the most frequent type of tumor of the central nervous system in children. Hence, it is important to describe markers that may improve our understanding of their behavior. Mature microRNAs (miRNAs) may be such biological markers. They are small molecules of RNA that regulate gene expression post-transcriptionally. Due to their importance in cancer, the objective of the present study was to determine the profile of expression of precursor and mature forms of miR-124-3p, miR-128-1, and miR-221-3p using RT-qPCR in pediatric samples. METHODS: A total of 57 astrocytomas embedded in paraffin were selected. As controls, the study included 13 samples of normal brain tissue. RESULTS: Three of eight miRNAs were selected after a preliminary screening. All the miRNAs showed higher levels of expression in normal brain tissue. The expression of miR-124-3p and miR-128-1 decreased in astrocytomas than in normal brain tissue in all grades (p < 0.05 in both cases), and this reduction was most evident in GIV (407- and 1,469-fold, respectively); however, the expression of the precursor forms pre-miR-128-1 and pre-miR-221 was higher in GIV (3.5-fold) than in GI. The levels of miR-128-1 were higher in infratentorial tumors than in supratentorial cases (p = 0.006). Finally, the expression of miR-221-3p was higher in non-recurrent tumors and live patients (p = 0.0185 and p = 0.0004, respectively). CONCLUSIONS: The low expression of these miRNAs may constitute a potential marker of astrocytomas that correlates with localization, possibly due to alterations in the maturation processes of these miRNAs that produced low mature forms in patients with recurrent pediatric astrocytomas.
PURPOSE:Astrocytomas are the most frequent type of tumor of the central nervous system in children. Hence, it is important to describe markers that may improve our understanding of their behavior. Mature microRNAs (miRNAs) may be such biological markers. They are small molecules of RNA that regulate gene expression post-transcriptionally. Due to their importance in cancer, the objective of the present study was to determine the profile of expression of precursor and mature forms of miR-124-3p, miR-128-1, and miR-221-3p using RT-qPCR in pediatric samples. METHODS: A total of 57 astrocytomas embedded in paraffin were selected. As controls, the study included 13 samples of normal brain tissue. RESULTS: Three of eight miRNAs were selected after a preliminary screening. All the miRNAs showed higher levels of expression in normal brain tissue. The expression of miR-124-3p and miR-128-1 decreased in astrocytomas than in normal brain tissue in all grades (p < 0.05 in both cases), and this reduction was most evident in GIV (407- and 1,469-fold, respectively); however, the expression of the precursor forms pre-miR-128-1 and pre-miR-221 was higher in GIV (3.5-fold) than in GI. The levels of miR-128-1 were higher in infratentorial tumors than in supratentorial cases (p = 0.006). Finally, the expression of miR-221-3p was higher in non-recurrent tumors and live patients (p = 0.0185 and p = 0.0004, respectively). CONCLUSIONS: The low expression of these miRNAs may constitute a potential marker of astrocytomas that correlates with localization, possibly due to alterations in the maturation processes of these miRNAs that produced low mature forms in patients with recurrent pediatric astrocytomas.
Authors: Jun Lu; Gad Getz; Eric A Miska; Ezequiel Alvarez-Saavedra; Justin Lamb; David Peck; Alejandro Sweet-Cordero; Benjamin L Ebert; Raymond H Mak; Adolfo A Ferrando; James R Downing; Tyler Jacks; H Robert Horvitz; Todd R Golub Journal: Nature Date: 2005-06-09 Impact factor: 49.962
Authors: S A Ciafrè; S Galardi; A Mangiola; M Ferracin; C-G Liu; G Sabatino; M Negrini; G Maira; C M Croce; M G Farace Journal: Biochem Biophys Res Commun Date: 2005-09-09 Impact factor: 3.575
Authors: Jakub Godlewski; Michal O Nowicki; Agnieszka Bronisz; Shanté Williams; Akihiro Otsuki; Gerard Nuovo; Abhik Raychaudhury; Herbert B Newton; E Antonio Chiocca; Sean Lawler Journal: Cancer Res Date: 2008-11-15 Impact factor: 12.701
Authors: Stefano Volinia; George A Calin; Chang-Gong Liu; Stefan Ambs; Amelia Cimmino; Fabio Petrocca; Rosa Visone; Marilena Iorio; Claudia Roldo; Manuela Ferracin; Robyn L Prueitt; Nozumu Yanaihara; Giovanni Lanza; Aldo Scarpa; Andrea Vecchione; Massimo Negrini; Curtis C Harris; Carlo M Croce Journal: Proc Natl Acad Sci U S A Date: 2006-02-03 Impact factor: 11.205