Quantitative protein changes in metastatic versus primary epithelial ovarian carcinoma

Primary and metastatic ovarian carcinomas from six patients were obtained during primary exploratory laparotomy. Tumor cells were synthetically radiolabeled with [35S]methionine. Radiolabeled cellular proteins of the primary and metastatic cells were examined by two-dimensional polyacrylamide gel electrophoresis followed by autoradiography. Computer assisted analysis of the resultant autoradiograms revealed that the amounts of only two proteins, p35 and p36, were consistently and significantly decreased in the metastatic tumor cells. No other consistent differences in protein synthesis between primary and metastatic tumors were detected.