en Pediatric Hematology & Oncology Pediatric Hematology & Oncology پژوهشي Original Article Neuroblastoma, one of the common malignant childhood tumors, arises from neuroblast cells derived from the<br>neural crest and destined for the adrenal medulla and the sympathetic nervous system and shows remarkable biological<br>heterogeneity, resulting in favorable or unfavorable outcomes. Some tumors make rapid progress with a fatal<br>outcome. In other instances, the tumors regress spontaneously in infants or to differentiate into a benign ganglioneuroma<br>in older patients. This heterogeneity within neuroblastoma depends on the molecular characteristics of tumor<br>cells. Several distinct genomic alterations have been found in neuroblastoma, including MYCN amplification, DNA<br>ploidy, deletion of the short arm of chromosome 1, gain of chromosome 17q, and deletion of 11q. The difference of<br>expression was also found in genes related to cellular growth, differentiation, and apoptosis of neural network including<br>signaling by NTRK1 or ALK receptor tyrosine kinases, and telomerase activity. And this presentation discusses<br>diagnostic and prognostic molecular makers for extensive heterogeneity of neuroblastoma. This should lead to more<br>risk-adapted therapies according to the genetic markers by which individual neuroblastomas are biologically characterized. Neuroblastoma, Prognosis, MYCN, Ploidy, Chromosome, Telomerase, Telomere, Apoptosis 49 60 http://ijbc.ir/browse.php?a_code=A-10-2-170&slc_lang=en&sid=1