Frequent loss of heterozygosity of the long arm of chromosome 7 is closely associated with progression of human gastric carcinomas

Abstract

Loss of heterozygosity (LOH) on the long arm of chromosome 7 was examined using 5 polymorphic marker probes on 98 gastric carcinomas to elucidate a novel locus for development and progression of the tumors. Twenty-six (32%) of 82 informative cases showed LOH on 7q on at least one locus of 5 loci. Among 5 loci, LOH at D7S95 locus was most frequent, the incidence being 53% in well-differentiated gastric carcinomas and 33% in poorly differentiated and scirrhous gastric carcinomas respectively. At 3 loci, c-met, D7S63 and D7S22, the incidence of LOH was about 30% and 10% in well-differentiated and poorly differentiated gastric carcinoma cases respectively. In contrast, LOH at D7S64 was not detected in any gastric-carcinoma cases. Deletion mapping of 7q revealed that D7S95 locus was the essential region of LOH. Eight (62%) of 13 cases with LOH at D7S95 locus belonged to the most advanced stage grouping. Furthermore, 6 (75%) of 8 cases with abdominal dissemination showed LOH at D7S95. Therefore, cases with LOH at D7S95 showed significantly worse prognosis than the cases without the LOH in the stage-III and stage-IV groups. These findings overall suggest that D7S95 locus on 7q may contain a candidate suppressor gene for the progression of gastric carcinoma.

Loss of heterozygosity on the long arm of human chromosome 7 in sporadic renal cell carcinomas

“…This enabled us to score for LOH more precisely. The deletion map generated from this study resembles similar SCDR reported by other groups for cancers in breast (Zenklusen et al, 1994a), colon (Zenklusen et al, 1995b), ovarian (Zenklusen et al, 1995a), prostate (Zenklusen et al, 1994b;Takahashi et al, 1995), pancreas (Achille et al, 1996), squamous cell carcinoma of the head and neck (Zenklusen et al, 1995b) and gastric carcinomas (Kuniyasu et al, 1994) for this region of the chromosome.…”

“…Six of the 10 markers chosen for this analysis map to 7q 31.1-31.2, a region that has been shown to have a high frequency of allele loss in several other tumor types (Zenklusen et al, 1994a(Zenklusen et al, , 1994b(Zenklusen et al, , 1995a(Zenklusen et al, , 1995bBieche et al, 1992;Achille et al, 1996;Takahashi et al, 1995;Kuniyasu et al, 1994). Table 1 summarizes the results of the samples that had LOH.…”

Missense Mutation of the MET Gene Detected in Human Glioma

“…Frequent allelic loss on chromosome 7q31 has been described for multiple cancers, including breast (32), gastric (33), and prostate (32) cancers. Likewise, allelic deletion without mutation of MET in our series may suggest the presence of a novel putative tumor suppressor gene at chromosome 7 near the MET locus, which may be involved in glioma formation.…”

Analysis of the CAVEOLIN-1 gene at human chromosome 7q31.1 in primary tumours and tumour-derived cell lines

“…Here, we report the mapping of the gene encoding Caveolin-1 to human chromosome 7q31, in proximity to the marker D7S522, which has been mapped to q31.1. A number of studies has revealed a high incidence of loss of heterozygosity (LOH) at 7q31 in a broad range of human tumours, including carcinomas of the breast (Bieche et al, 1992;Zenklusen et al, 1994a), colon (Zenklusen et al, 1995a), kidney (Shridhar et al, 1997), ovary (Kerr et al, 1996;Koike et al, 1997;Zenklusen et al, 1995b), pancreas (Achille et al, 1996), prostate (Takahashi et al, 1995;Zenklusen et al, 1994b), and stomach (Kuniyasu et al, 1994), as well as squamous cell carcinomas of the head and neck (Zenklusen et al, 1995a, Loughran et al, 1997. The highest frequency of LOH was observed at D7S522.…”