Expression of proto-oncogene Wip1 in breast cancer and its clinical significance

Abstract

To investigate the expression of proto-oncogene Wip1 in breast cancer tissue and its clinical significance. Through the uses of semi-RT-PCR, immunohistochemical technique and Western blot, the specimens from 70 patients of breast cancer and 20 normal controls were detected for Wip1 mRNA and protein expression. At the same time, the authors analyzed the relations between the expression of Wip1 in human breast cancer and different clinical pathologic parameters. RT-PCR: The values of gene expression of Wip1 mRNA in breast cancer tissue, pericancerous tissue and normal breast tissue were 0.715 +/- 0.087, 0.175 +/- 0.021 and 0.154 +/- 0.022 respectively. Thus the value of gene expression in breast cancer tissue was significantly higher than that in pericancerous tissue or normal breast tissue (P < 0.01). Immunohistochemistry: The high expression rates of Wip1 protein in breast cancer tissue, pericancerous tissue and normal breast tissue were 62.9% (44/70), 2.9% (2/70) and 0 (0/20) respectively and there was a significant difference among these three different tissues (P < 0.01). Western blot: The relative contents of Wip1 protein in breast cancer tissue, pericancerous tissue and normal breast tissue were 0.688 +/- 0.151, 0.251 +/- 0.043 and 0.234 +/- 0.044 respectively. The relative content of Wip1 protein in breast cancer tissue was significantly higher than that in pericancerous tissue or normal breast tissue (P < 0.01). The high expression of Wip1 protein was negatively correlated with the expression of p53, but it had nothing to do with tumor size, age, tumor staging, axillary lymph node metastasis and expressions of ER and PR. The high expression of Wip1 mRNA and its protein in breast cancer tissue may promote the growth of breast cancer. Wip1 may become a new target for therapy of breast cancer.