title: The p53/p21 DNA damage-signaling pathway is defective in most meningioma cells.
abstract: Although meningiomas represent the most common class of tumors of the central nervous system, the molecular events underlying their genesis and development are still not well defined. In the present study we have used the immuno-blotting technique to study the expression level of the tumor suppressor proteins p53, p21 and PTEN in primary meningioma cells. We have also studied the induction of p21 and p53 in response to both UV light and gamma-rays. We present evidence that the p53/p21-dependent gamma-ray signaling pathway is defective in 5 out of 8 (62%) of these cells. Furthermore, we have shown that the tumor suppressor p21, p53 and PTEN proteins are differently expressed in these cells, with up to 40-folds difference between the lowest and the highest levels of each protein. These results suggest that the tumor suppressors p53/p21 signaling pathway and PTEN play important roles in the development of benign meningiomas.
authors.affiliation: Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Center, MBC# 03-66, 3354, Riyadh 11211, KSA.
authors.forename: Huda H
authors.initials: HH
authors.lastname: Al-Khalaf
authors.forename: Boleslaw
authors.initials: B
authors.lastname: Lach
authors.forename: Ayman
authors.initials: A
authors.lastname: Allam
authors.forename: Ahmed
authors.initials: A
authors.lastname: AlKhani
authors.forename: Salman A
authors.initials: SA
authors.lastname: Alrokayan
authors.forename: Abdelilah
authors.initials: A
authors.lastname: Aboussekhra
mesh_terms: D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics* / Q000378:metabolism; D004249:DNA Damage; D005720:Gamma Rays; D016158:Genes, p53; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D008577:Meningeal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008579:Meningioma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D015398:Signal Transduction / Q000528:radiation effects; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D008565:Membrane Proteins; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; C446603:TPTE protein, human; D051059:PTEN Phosphohydrolase