Based on our recent studies showing cyclin D1 overexpression in both Ewing sarcoma/primitive peripheral neuroectodermal tumor (EWS/pPNET) and peripheral neuroblastic tumors (neuroblastoma and ganglioneuroblastoma), we immunohistochemically assessed cyclin D1 immunoreactivity in 128 cases of SRBCTs in children and adolescents to establish its potential utility in the differential diagnosis.
These results demonstrated a dependency in Ewing sarcoma on CDK4 and cyclin D1 and support exploration of CDK4/6 inhibitors as a therapeutic approach for patients with this disease.
A recent study shows that an alteration of EWS in Ewing sarcoma alters the dynamics of RNA polymerase II over the CCND1 proto-oncogene encoding cyclin D1, leading to an increase in its transcription and to an alteration of splicing that results in high levels of the oncogenic cyclin D1b splice isoform.
To this end, we analyzed the expression of four tumor-promoting proteins, cyclin D1, HER2/Neu, Mdm2, and vascular endothelial growth factor (VEGF), in Ewing's sarcoma.