DETECTION OF ALTERED APC PROTEINS IN COLON CANCER CELLS

APC基因的突变似乎是腺瘤形成的关键， 遗传性家族性腺瘤性息肉病（FAP）和早期阶段 结直肠癌的症状 对APC基因的分析已经确定了突变 FAP患者的生殖细胞DNA中。 超过90%的突变 该阅读框提示存在截短的APC蛋白。 我们已经开发了一系列抗APC抗体， APC的氨基末端部分。 这些抗体已经识别出 携带突变APC的SW480细胞中APC蛋白的截短形式 等位基因 我们将检测一系列肿瘤细胞系和正常细胞 APC蛋白的改变形式与存在 结肠直肠癌 我们将集中在细胞系中， APC的结构是已知的，无论是野生型还是突变型。 我们还将 开始产生针对APC中羧基末端结构域的抗体， 用于区分全长与截短的APC蛋白。 在 第二阶段，抗氨基末端和抗羧基的组合 末端APC抗体将用于开发一种检测方法， 确定临床样品中的APC状态作为以下疾病的预后测试： FAP与结直肠癌

Mutations in the APC gene appear to be crucial for adenoma formation in inherited Familial Adenomatous Polyposis (FAP) and in the early stages of colorectal cancer. Analysis of the APC gene has identified mutations in germ line DNA of FAP patients. Over 90% of the mutations interrupt the reading frame suggesting the presence of a truncated APC protein. We have developed a series of anti-APC antibodies directed against the amino terminal portion of APC. These antibodies have identified a truncated form of APC protein in SW480 cells carrying mutated APC alleles. We will examine a series of tumor cell lines and normal cells for altered forms of APC protein associated with the presence of colorectal cancer. We will concentrate on cell lines in which the structure of APC is known, either wild type of mutated. We will also begin generating antibodies to carboxyl terminal domains in APC that will be used to discriminate full length versus truncated APC proteins. In Phase II, the combination of anti-amino terminal and anti-carboxyl terminal APC antibodies will be used to develop an assay for determination of APC status in clinical samples as a prognostic test for FAP and colorectal cancer.