Breast cancer of Taiwan;p53 gene;SSCP;Direct DNA Sequencing

• Main Authors: Chen, Li-Jung, 陳麗容
• Other Authors: Shew, Jin-Yuh
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/70259252308968030663

碩士 === 國立臺灣大學 === 化學研究所 === 84 === Breast cancer is the most common malignancy cancer of women in Western countries. The mortality rate have held almost steady over the past 20 years, even though the number of new cases has grown. From 1970 to 1990, breast cancer is an important cancer of women in Taiwan and incidence of age in breast cancer trend to early onset. At molecular level, various genetic alteration have been implicated in the development of breast cancer. Loss of heterozygosity(LOH) at five different regions of human genome,including chromosome 1q, 3p, 11p, 13q and 17p, has been observed in a high percentage of primary breast cancer. Because the extremely high frequency(60%) of p53 mutation in primary breast cancer of Western countries, we will focus on mutations of the p53 tumor suppressor gene in breast cancer of Taiwan. First, we use immunohistochemical analysis to determine whether p53 gene expression in 171 breast cancer specimen of Taiwan can be detected. Second,the validity of p53 immunopositivity as an indicator for p53 mutation was verified using two molecular assays of p53 mutation: Single Strand Conformation Polymorphism(SSCP) and direct DNA sequencing. We have found p53 mutations in 26.9% of the breast cancer specimen in Taiwan. In addition, the mutation patterns of p53 gene mainly locate at exon 7∼8 and G to A (22%) transition is the major type of nucleotide changes. But in Western countries, the mutation patterns of p53 gene major locate at exon 5∼6 and C to G (20%) transversion is the major type of nucleotide changes. The spectrum of mutation in breast cancer of Taiwan differs from that of Western countries, further indicating that unknown carcinogens involve in the formation of breast cancer in Taiwan.