|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1994 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1993 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Allelic loss on chromosomal region, 16q22.1, harboring E-cadherin have been demonstrated in prostate, breast, and hepatocellular carcinomas. We investigated allelic loss of chromosome 16q and expression of E-cadherin in ovarian and endometrial cancers in order to reveal the suppressive role of E-cadherin to tumor progression. Paired normal and tumor tissue DNAs were extracted from 26 cases with ovarian cancer and 50 cases with endometrial cancer, and analyzed loss of heterozygosity (LOH) of chromosome 16q. Tissue sections from 15 cases of ovarian cancer and 15 cases of endometrial cancer were immunohistochemically examined for expression of the E-cadherin. LOH of chromosome 16q was detected in 15 (58%) of 26 ovarian cancers, and in 21 (42%) of 50 endometrial cancers. Most cases of ovarian cancer showing LOH were advanced stage. In endometrial cancer, LOH was significantly correlated with histological grade, and the patients' survival. Immunohistochemical staining pattern of E-cadherin was classified as absent, heterogenous, and homogenous staining on cell to cell border. Absent and heterogenous staining were considered as reduced expression of E-cadherin with comparison of staining on normal tissue. Reduced expression of the E-cadherin was observed 60% (9/15) in ovarian cancer, and 27% (4/15) in endometrial cancer. Reduced expression of the E-cadherin was associated with LOH of chromosome 16q, although not significant. These results indicate that reduced expression of the E-cadherin and LOH of chromesome 16q were associated with tumor progression.
E cadherinが存在する染色体領域(16q22.1)は卵巣癌,子宮内膜癌において高頻度に欠損し,E cadherinの発現減弱が高頻度に認められたためE cadherinはこれらの癌における癌抑制遺伝子の候補である可能性が示唆された。さらに16q12.1-12.2も高頻度に欠損が認められたため,この領域にも癌抑制遺伝子の存在が示唆された。