Novel Growth Factor as Prognostic Marker for Estrogen-Independence in Breast Cancer

Abstract

Abstract : The goal of this study was to examine the expression in human breast cancer biopsies of a novel growth factor, called PC-cell derived growth factor (PCDGF) characterized in our laboratory, and examine correlation of PCDGF expression with clinical parameters and with known prognosis markers of breast cancer. Previous biological studies with human breast cancer cell lines have indicated the role of PCDGF in the tumorigenicity of breast carcinoma and identified it as a molecular target of estrogen-independence and tamoxifen resistance. Here, wave conducted a study with 206 paraffin embedded human breast cancer biopsies and measured PCDGF expression by immunohistochemistry using an anti-PCDGF developed in our laboratory. We show that PCDGF is not expressed in normal epithelium and in benign tumors. PCDGF was preferentially expressed in situ and invasive ductal carcinoma where its expression correlated with tumor grade. PCDGF expression significantly correlated with steroid receptor status, high proliferation index (Ki-67) and p53 expression. In contrast PCDGF expression was independent of erbB2 expression. These studies have provided novel information on the expression of a novel autocrine growth factor in human breast cancer biopsies. Future studies are proposed to examine the correlation of PCDGF expression with response to therapy in advanced breast carcinoma.