Maestro R, Piccinin S, Doglioni C, Gasparotto D, Vukosavljevic T, Sulfaro S, Barzan L, Boiocchi M
Division of Experimental Oncology 1, Centro di Riferimento Oncologio, Pordenone, Italy.
Cancer Res. 1996 Mar 1;56(5):1146-50.
Heal and neck squamous cell carcinomas show frequent cytogenetic alterations involving the long arm of chromosome 13. To define the extent of 13q deletions and to identify the minimal areas of chromosome loss, 48 primary squamous cell carcinomas of the head and neck were analyzed for loss of heterozygosity using 11 different polymorphic loci. About 67% of the tumors displayed loss of genetic material at 13q. Most of the cases showed loss of the entire long arm of the chromosome. However, the presence of partial deletions in 10 cases provided evidence of the existence of two preferential sites of chromosome loss at 13q32-ter and 13q14.2-q14.3. The colocalization of the 13q14 minimal region of deletion with the retinoblastoma (RB) gene, which has been proposed as an oncosuppressor in diverse tumor types, prompted us to verify the involvement of this gene in the development of head and neck cancer. No significant variation in RB protein or RB mRNA expression was detected, thus excluding a role for such a gene in the genesis of this type of tumor. Taken together, our data suggest the existence of two new tumor suppressor genes (one close to and one distal to RB), which play a role in the development and/or progression of head and neck squamous cell carcinomas.
头颈部鳞状细胞癌显示出频繁的细胞遗传学改变，涉及13号染色体长臂。为了确定13q缺失的范围并识别染色体缺失的最小区域，使用11个不同的多态性位点对头颈部48例原发性鳞状细胞癌进行杂合性缺失分析。约67%的肿瘤在13q处显示遗传物质缺失。大多数病例显示整个染色体长臂缺失。然而，10例中存在部分缺失，这为13q32-末端和13q14.2-q14.3存在两个优先染色体缺失位点提供了证据。13q14最小缺失区域与视网膜母细胞瘤（RB）基因共定位，RB基因在多种肿瘤类型中被认为是一种肿瘤抑制基因，这促使我们验证该基因在头颈部癌发生中的作用。未检测到RB蛋白或RB mRNA表达的显著变化，因此排除了该基因在这类肿瘤发生中的作用。综上所述，我们的数据表明存在两个新的肿瘤抑制基因（一个靠近RB，一个在RB远端），它们在头颈部鳞状细胞癌的发生和/或进展中起作用。
