Mutational and functional analyses reveal that ST7 is a highly conserved tumor-suppressor gene on human chromosome 7q31.
Loss of heterozygosity (LOH) of markers on human chromosome 7q31 is frequently encountered in a variety of human neoplasias, indicating the presence of a tumor-suppressor gene (TSG). By a combination of microcell-fusion and deletion-mapping studies, we previously established that this TSG resides within a critical region flanked by the genetic markers D7S522 and D7S677. Using a positional cloning strategy and aided by the availability of near-complete sequence of this genomic interval, we have identified a TSG within 7q31, named ST7 (for suppression of tumorigenicity 7; this same gene was recently reported in another context and called RAY1). ST7 is ubiquitously expressed in human tissues. Analysis of a series of cell lines derived from breast tumors and primary colon carcinomas revealed the presence of mutations in ST7. Introduction of the ST7 cDNA into the prostate-cancer-derived cell line PC3 had no effect on the in vitro proliferation of the cells, but abrogated their in vivo tumorigenicity. Our data indicate that ST7 is a TSG within chromosome 7q31 and may have an important role in the development of some types of human cancer.
Zenklusen
J C
JC
Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA.
Conti
C J
CJ
Green
E D
ED
D000595:Amino Acid Sequence; D001483:Base Sequence; D002874:Chromosome Mapping; D002897:Chromosomes, Human, Pair 7; D004247:DNA; D016147:Genes, Tumor Suppressor; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D014162:Transfection; D014407:Tumor Cells, Cultured
D008565:Membrane Proteins; D012333:RNA, Messenger; D004247:DNA