Human gliomas with wild-type p53 express bcl-2.
Human astrocytomas frequently overexpress wild-type p53, which suggests that gliomas have evolved a mechanism to subvert p53-mediated apoptosis. bcl-2 inhibits apoptosis mediated by p53, and it is expressed in several human cancers. We therefore examined a series of human gliomas to determine whether bcl-2 is expressed and whether this expression is associated with tumors which have wild-type p53. Twenty-eight paraffin-embedded gliomas (3 WHO grade II, 13 grade III, 12 grade IV) were immunohistochemically stained for bcl-2 and p53. p53 mutations were identified with single strand conformation polymorphism and DNA sequencing. Sixteen of 28 (57%) tumors expressed bcl-2, and bcl-2 expression was associated with wild-type p53 (P < 0.01). Among gliomas which overexpressed p53, bcl-2 was positive in 7 of 7 tumors with wild-type p53 but in only 1 of 7 with mutant p53 (P < 0.01). We conclude that bcl-2 is frequently expressed in human gliomas and that expression is more common in tumors with wild-type p53.
Alderson
L M
LM
Molecular Neuro-Oncology Laboratory, Massachusetts General Hospital, Charlestown 02129.
Castleberg
R L
RL
Harsh
G R
GR
Louis
D N
DN
Henson
J W
JW
D017209:Apoptosis / Q000502:physiology; D001254:Astrocytoma / Q000737:chemistry* / Q000235:genetics / Q000473:pathology; D015870:Gene Expression; D016158:Genes, p53 / Q000235:genetics; D005910:Glioma / Q000737:chemistry* / Q000235:genetics / Q000473:pathology; D007150:Immunohistochemistry; D009154:Mutation; D016612:Paraffin Embedding; D011518:Proto-Oncogene Proteins / Q000032:analysis* / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53 / Q000032:analysis* / Q000235:genetics
D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53