Hepatocyte growth factor (HGF) is a stromally derived modulator of epithelial cell proliferation and motility. In the present study, we have measured immunoreactive (ir)-HGF concentration in tumor extracts of 258 primary human breast cancers using an enzyme-linked immunosorbent assay and have evaluated its association with disease-free and overall survival. The median value of ir-HGF concentration was 11.0 ng/100 mg protein (range, 1.4–566.7 ng/100 mg protein). Correlation analyses between ir-HGF concentration and clinicopathological factors showed that the ir-HGF level was correlated only with tumor size (P = 0.05). No significant associations were found between ir-HGF content and age, menopausal status, nodal status, histological type, histological grade, vessel involvement, estrogen receptor, progesterone receptor, type of surgery, or postoperative adjuvant therapy. Breast cancer patients with high ir-HGF concentration had a significantly shorter relapse-free (P = 0.001) and overall survival (P = 0.001) rate when compared to those with low ir-HGF concentration at the cutoff point of 21.7 ng/100 mg protein, which was determined in another group of 82 patients. In multivariate analysis, ir-HGF level was found to be the most important independent factor in predicting relapse-free and overall survival, of greater import than lymph node involvement. The putative role of HGF in breast cancer growth and metastasis is hereby strengthened.
This work was supported by Grant-in-Aid 05151061 for Scientific Research from the Ministry of Education, Science and Culture of Japan.