Expression of glycodelin protein and mRNA in human ductal breast cancer carcinoma in situ, invasive ductal carcinomas, their lymph node and distant metastases, and ductal carcinomas with recurrence

Glycodelin, previously known as PP14, has been localized in endometrial, ovarian and cervical carcinoma cells. Recently, glycodelin was demonstrated to be expressed in cancerous human breast tissue. In this study, paraffin-embedded slides of carcinoma in situ, invasive carcinomas without metastases, invasive carcinomas with corresponding lymph node metastases, invasive carcinomas with corresponding recurrence and invasive carcinomas with corresponding distant metastases were investigated for glycodelin protein and mRNA expression. Protein expression was found in all cases of carcinoma in situ, in invasive carcinoma without lymph node metastases in 90% of cases, in breast cancer with lymph node metastases in 50% of cases, in breast cancer with recurrence in 38% of cases and in breast cancer with distant metastases in 40% of cases. Results were confirmed by in situ hybridization showing reduced glycodelin expression as lymph node metastasis progressed, compared to carcinoma in situ. Glycodelin mRNA expression is not further reduced in carcinomas with distant metastasis and recurrence compared to carcinoma in situ. Results demonstrate that invasive breast carcinomas without metastases are more likely to express glycodelin. In contrast, cases of breast cancer with metastatic infiltration and recurrence show weak expression of glycodelin. On the basis of these results, we speculate that glycodelin could be used as a prognostic marker for breast cancer.