Overexpression of protein tyrosine phosphatase gamma in Taiwanese women with breast cancers

• Main Authors: Ju-Fan Lin, 林如璠
• Other Authors: Kuan-Chih Chow
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/00907496886380456768

碩士 === 國立中興大學 === 生物醫學研究所 === 96 === Breast cancer is a leading cause of cancers in Taiwanese women. The incidence and mortality rate increased rapidly in the past two decades. The average onset age of breast cancer in Taiwan is 8-10 years younger than that in Euro-America. However, the molecular difference is still unclear. Protein tyrosine phosphatase gamma (PTPγ) is located at chromosome 3p14.2. This molecule is suggested as a tumor suppressor candidate, but is up-regulated during lymphoma and astrocytoma tumorigenesis. In this study, we found that PTPγ was overexpressed in breast cancer cell lines and breast cancer specimens by using RT-PCR, in situ hybridization, and western blot analysis. However, no specific deletion or mutation was found in PTPγ of cancer cell lines or clinical samples. Immunohistochemical staining showed that PTPγ was mainly distributed in tumor lesion, and surprisingly, PTPγ was located in the nucleus in about 30% of tumor samples. Moreover, we found that nearly all infiltrating ductal carcinoma (IDC), but only 58% infiltrating lobular carcinoma (ILC) patients had high level of PTPγ expression. These data indicated that PTPγ is a potential oncogene and may be a prognostic factor and therapeutic target of breast cancer in Taiwan.