BackgroundMedulloblastomas (MBs), atypical teratoid/rhabdoid tumors (AT/RTs) and central nervous system primitive neuroectodermal tumors (PNETs) are aggressive embryonal brain neoplasms in children with overlapping histological features but with different pathogenetic pathways.Abnormalities of the cell cycle, apoptosis and signal transduction are molecular features of many brain tumors and are currently under evaluation for potential therapeutic intervention.Despite previous investigations, the role of p-53 tumor suppressor oncoprotein, cyclin Α, cyclin Β1, cyclin D3 and cyclin Ε, p27/kip-1 cyclin/CDK inhibitor, bcl-2 anti-apoptotic protein, epidermal growth factor receptor (EGFR), c-erbB2/HER-2 and c-kit in the pathogenesis of embryonal br...