FHIT GENE ALTERATIONS IN CERVICAL CANCER PATHOGENESIS

描述：（改编自研究者摘要）宫颈癌 导致世界各地妇女发病率和死亡率很高。 染色体3 p13 -14.3区域杂合性丢失（洛）频率较高 浸润性宫颈癌及其上皮内前体病变。 部分基于其在3p14.2的定位，FHIT（脆性组氨酸） triad）是宫颈癌中的候选3 p肿瘤抑制基因。 体细胞 FHIT突变，包括基因内纯合缺失和整合 将人乳头瘤病毒（HPV）序列插入FA 3B/FHIT脆性位点， 仅在少数宫颈癌中检测到。 然而，改变的FHIT 已经在大约1000例中发现了mRNA和Fhit蛋白的显著减少或缺失。 70%的宫颈癌，表明FHIT改变可能是常见的 在宫颈癌中也很重要 本提案的目标是确定 宫颈癌中FHIT改变的患病率、性质和意义 癌症，并确定Fhit表达是否是一个预后标志物， 宫颈癌和癌前病变。 提出了四个具体目标：1） Fhit蛋白在宫颈癌前病变中的表达。 的 FHIT失活在上皮内瘤变进展中的作用 将使用免疫组织化学研究癌以评估Fhit蛋白 在正常宫颈及不同程度的癌前病变中表达。 的 FHIT洛缺失和Fhit蛋白表达缺失之间的关系也将 接受检查。 2)确定3 p14.2洛杂合性缺失和Fhit表达缺失是否 浸润性宫颈癌的预后标志物。 染色体3 p洛缺失和 癌标本中FHIT蛋白表达将与生存期相关 在一个大型的宫颈癌患者队列中， 数据已经可用。 3)识别体细胞突变，如HPV 整合和纯合缺失。 双色荧光原位杂交将用于鉴定HPV 在原发性肿瘤和细胞系中的FRA 3B/FHIT基因座中的整合。 将使用基于PCR和Southern印迹分析来鉴定纯合子 FHIT中的缺失。 4)为了证明FHIT抑制肿瘤发生， 宫颈癌的症状 一组同基因型宫颈癌细胞 仅Fhit表达式不同的行将用in表示 体外和体内试验，包括集落形成，生长速率， 单层和器官型筏培养中的形态学，凋亡，锚定 在裸鼠中的独立生长和致瘤性。 拟议的研究 将为宫颈癌的发病机制提供新的见解， 确定改善这种临床管理的预后标志物， 疾病

DESCRIPTION: (adapted from the investigator's abstract) Cervical cancer causes significant morbidity and mortality for women throughout the world. Frequent loss of heterozygosity (LOH) of chromosome 3p13-14.3 has been seen in invasive cervical carcinoma and its intraepithelial precursor lesions. Based in part on its localization at 3p14.2, FHIT (for fragile histidine triad) is a candidate 3p tumor suppressor gene in cervical cancer. Somatic mutations in FHIT, including intragenic homozygous deletions and integration of human papillomavirus (HPV) sequences into the FA3B/FHIT fragile site, have been detected in only a few cervical cancers. However, altered FHIT mRNAs and markedly reduced or absent Fhit protein have been found in about 70% of cervical carcinomas, suggesting that FHIT alterations may be frequent and important in cervical cancer. The goals of this proposal are to define the prevalence, nature, and significance of FHIT alterations in cervical cancer, and to determine if Fhit expression is a prognostic marker in cervical cancers and precancers. Four Specific Aims are propose: 1) To characterize Fhit protein expression in precancerous cervical lesions. The role of FHIT inactivation in the progression of intraepithelial neoplasia to carcinoma will be studied using immunohistochemistry to assess Fhit protein expression in normal cervix and precancerous lesions of various grads. The relationship between FHIT LOH and loss of Fhit protein expression will also be examined. 2) To determine if 3p14.2 LOH and loss of Fhit expression are prognostic markers in invasive cervical carcinomas. Chromosome 3p LOH and Fhit protein expression in cancer specimens will be correlated with survival in a large cohort of cervical cancer patients for whom excellent follow-up data are already available. 3) To identify somatic mutations, such as HPV integration and homozygous deletion, in FHIT in cervical carcinomas. Two-color fluorescence in situ hybridization will be used to identify HPV integration in the FRA3B/FHIT locus in primary tumors and cell lines. PCR-based and Southern blot analyses will be used to identify homozygous deletions in FHIT. 4) To demonstrate that FHIT suppresses the tumorigenic properties of cervical cancers. A panel of isogenic cervical cancer cell lines that differ only in Fhit expression will be characterized with in vitro and in vivo assays, including colony formation, growth rate, morphology in monolayer and organotypic raft cultures, apoptosis, anchorage independent growth and tumorigenicity in nude mice. The proposed studies will offer new insights into cervical cancer pathogenesis, and may also identify prognostic markers that improve the clinical management of this disease.