Absence of p53 gene mutations in primary nasopharyngeal carcinomas.
Alterations in the p53 tumor suppressor gene and Epstein-Barr virus status were investigated in 15 nasopharyngeal carcinoma (NPC) biopsies, 4 xenografts, and 2 cell lines from the Cantonese region of southern China. One other established NPC cell line obtained from a northern Chinese patient was also studied. Restriction fragment length polymorphism analysis revealed a loss of heterozygosity for chromosome 17p, where the p53 gene resides, in only one of 15 NPC biopsies. Polymerase chain reaction-single-stranded conformational polymorphism analysis and direct sequencing failed to detect sequence alterations in exons 5 through 8 of the p53 gene in the 15 tumors and in the 4 NPC xenografts, all of which tested positive for Epstein-Barr virus. In contrast, the 3 NPC cell lines were all negative for Epstein-Barr virus and contained G----C transversions in the p53 gene, with cell lines CNE-1 and CNE-2 harboring identical AGA (arginine) to ACA (threonine) changes at codon 280. These results suggest that p53 inactivation is not a necessary component of nasopharyngeal carcinogenesis in Cantonese but may be important in the establishment of cell lines derived from these tumors.
Spruck
C H
CH
Kenneth Norris Jr. Comprehensive Cancer Center, University of Southern California, Los Angeles 90033.
Tsai
Y C
YC
Huang
D P
DP
Yang
A S
AS
Rideout
W M
WM
Gonzalez-Zulueta
M
M
Choi
P
P
Lo
K W
KW
Yu
M C
MC
Jones
P A
PA
D001483:Base Sequence; D002277:Carcinoma / Q000235:genetics*; D002886:Chromosomes, Human, Pair 17; D004273:DNA, Neoplasm / Q000235:genetics; D016158:Genes, p53; D006801:Humans; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D009154:Mutation; D009303:Nasopharyngeal Neoplasms / Q000235:genetics*; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D016133:Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D004273:DNA, Neoplasm; D009838:Oligodeoxyribonucleotides