is a negative regulator of p53 and genomic aberrations resulting in increased activity of have been observed in cancers of different origins, indicating that has oncogenic properties. We established a transgenic mouse model overexpressing and showed that these mice developed a wide variety of cancers. -expressing mice developed tumors phenotypically and genetically similar to tumors in mice with dysfunctional p53.
View Article and Find Full Text PDFMalignant cells display an increased sensitivity towards drugs that reduce the function of the ubiquitin-proteasome system (UPS), which is the primary proteolytic system for destruction of aberrant proteins. Here, we report on the discovery of the bioactivatable compound CBK77, which causes an irreversible collapse of the UPS, accompanied by a general accumulation of ubiquitylated proteins and caspase-dependent cell death. CBK77 caused accumulation of ubiquitin-dependent, but not ubiquitin-independent, reporter substrates of the UPS, suggesting a selective effect on ubiquitin-dependent proteolysis.
View Article and Find Full Text PDFThe majority of anti-cancer therapies target the proliferating tumor cells, while the tumor stroma, principally unaffected, survives, and provide a niche for surviving tumor cells. Combining tumor cell and stroma-targeting therapies thus have a potential to improve patient outcome. The neuroblastoma stroma contains cancer-associated fibroblasts expressing microsomal prostaglandin E synthase-1 (mPGES-1).
View Article and Find Full Text PDFAbnormal increases in nucleolar size and number caused by dysregulation of ribosome biogenesis has emerged as a hallmark in the majority of spontaneous cancers. The observed ribosome hyperactivity can be directly induced by the MYC transcription factors controlling the expression of RNA and protein components of the ribosome. Neuroblastoma, a highly malignant childhood tumor of the sympathetic nervous system, is frequently characterized by MYCN gene amplification and high expression of MYCN and c-MYC signature genes.
View Article and Find Full Text PDFDespite recent progress in diagnosis and treatment, survival for children with high-risk metastatic neuroblastoma is still poor. Prostaglandin E (PGE)-driven inflammation promotes tumor growth, immune suppression, angiogenesis and resistance to established cancer therapies. In neuroblastoma, cancer-associated fibroblasts (CAFs) residing in the tumor microenvironment are the primary source of PGE.
View Article and Find Full Text PDFBackground: The TH-MYCN transgenic neuroblastoma model, with targeted MYCN expression to the developing neural crest, has been used to study neuroblastoma development and evaluate novel targeted tumor therapies.
Methods: We followed tumor development in 395 TH-MYCN (129X1/SvJ) mice (125 negative, 206 hemizygous and 64 homozygous mice) by abdominal palpations up to 40 weeks of age. DNA sequencing of MYCN in the original plasmid construct and mouse genomic DNA was done to verify the accuracy.