Mutational analysis of the NM23.H1 gene in human breast cancer.
NM23.H1 is a protein connected with tumor progression. Loss of heterozygosity and reduced expression of the gene have been associated with poor prognosis and increased incidence of metastases in many epithelial tumors. The aim of this study was to detect the presence of NM23.H1 point mutations or small deletions in human breast carcinomas by using the single-strand-conformation polymorphism (SSCP) technique. Mutational analysis was performed on 76 breast tumors, 10 of which had allelic deletion of the gene. The NM23.H1 mRNA content also was evaluated in each sample. Only a C-to-A transversion leading to a stop codon was found in the 5' untranslated region of exon 1. A polymorphic SSCP pattern was identified in exon 1; direct sequencing showed a C-to-T transition 30 nucleotides upstream from the 5' splice site flanking exon 1. None of the tumors analyzed presented both alleles inactivated. Our results suggest that NM23.H1 is rarely inactivated by point mutations.
Cipollini
G
G
Department of Oncology, Division of Pathology, Laboratory of Molecular Genetics, University of Pisa, Pisa, Italy.
Moretti
A
A
Ghimenti
C
C
Viacava
P
P
Bevilacqua
G
G
Caligo
M A
MA
D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D004252:DNA Mutational Analysis; D006801:Humans; D019656:Loss of Heterozygosity; D008875:Middle Aged; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics*; D054778:NM23 Nucleoside Diphosphate Kinases; D009701:Nucleoside-Diphosphate Kinase; D018807:Polymorphism, Single-Stranded Conformational; D012333:RNA, Messenger / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics*
D054778:NM23 Nucleoside Diphosphate Kinases; D012333:RNA, Messenger; D014157:Transcription Factors; C517938:NME1 protein, human; D009701:Nucleoside-Diphosphate Kinase; D020559:Monomeric GTP-Binding Proteins