Figure 7From: Modulation of CXCR3 ligand secretion by prostaglandin E2 and cyclooxygenase inhibitors in human breast cancerCorrelation between cyclooxygenase and CXCL9 expression in human breast cancer tissue samples. Homogenates were prepared from deep-frozen breast cancer tissue samples and analyzed for COX-1 and COX-2 expression by western blot analysis. Panel a shows representative immunoblots with high (first lane) and low (second lane) expression of both enzymes. For both cyclooxygenase isoenzymes samples were divided into a low and a high expressing group (see text for further details), and CXCL9 concentration was determined in all samples by ELISA. There was a trend towards lower CXCL9 expression in the high COX-1 expressing group (b; n low = 22, n high = 21), but a significantly reduced CXCL9 concentration in highly COX-2 expressing breast cancers (c; n low = 12, n high = 17). COX-2 overexpressing breast cancers display only half of the average CXCL9 concentration found in low-expressing cancers (56.5% ± 13.9%). (b and c) CXCL9/total protein ratio is presented as arbitrary units with 1.0 set as the arithmetic mean of the low expressing group. Horizontal lines in b and c represent the arithmetic mean.Back to article page