A candidate tumor suppressor gene in human breast cancers.
We have isolated a candidate gene (designated Brush-1) located at 13q12-q13, proximal to the retinoblastoma gene (RB1). Brush-1 codes for a 4.7-kilobase mRNA expressed at high levels in normal breast epithelium but drastically reduced in 6 of 13 breast cancer cell lines. RB1 mRNA expression is at normal levels for 5 of these 6 lines suggesting a greater importance of Brush-1 for breast cancer. Four primary breast tumors which showed no loss of heterozygosity in the 13q13-q14 region demonstrated normal levels of mRNA for both Brush-1 and RB1. However, four additional primary tumors which displayed loss of heterozygosity for this region had markedly decreased levels of Brush-1 mRNA while maintaining the normal levels for RB1. This differential loss of Brush-1 mRNA expression for both primary tumors and breast cancer cell lines is the expected pattern for a breast tumor suppressor gene.
Schott
D R
DR
Geraldine Brush Cancer Research Institute, California Pacific Medical Center, San Francisco 94115-1932.
Chang
J N
JN
Deng
G
G
Kurisu
W
W
Kuo
W L
WL
Gray
J
J
Smith
H S
HS
D001483:Base Sequence; D015152:Blotting, Northern; D001940:Breast / Q000737:chemistry / Q000502:physiology; D001943:Breast Neoplasms / Q000235:genetics*; D002874:Chromosome Mapping; D002882:Chromosomes, Human, Pair 13; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D015870:Gene Expression / Q000235:genetics; D016161:Genes, Retinoblastoma / Q000235:genetics; D016147:Genes, Tumor Suppressor / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D014407:Tumor Cells, Cultured
D004273:DNA, Neoplasm; D012333:RNA, Messenger