Fig. 1.

Immunohistochemical analysis of CD39 and CD73 expression in OvCa tissue. a Immunohistochemical staining of 36 serous papillary epithelial OvCAs showed moderate to strong expression of CD39 in 29 of 36 samples. Representative samples are shown in the middle and the right panel. In contrast, 8 out of 9 tissue samples from benign ovaries were negative for CD39 with exception of vascular endothelial cells providing an internal control (left). b CD73 immunoreactivity was detected in 8/9 benign ovaries (a representative staining is shown in the left panel) and in 31/34 epithelial OvCAs of the serous papillary subtype (see middle and right panel). c, d To examine the expression of CD39 (c) and CD73 (d) on tumour and stromal cells, immunofluorescent double staining were performed for EpCAM/CD326 (green) and either CD39 or, respectively, CD73 (red) and. Shown is one representative sample where both ectonucleotidases are mainly expressed on tumour cells. Size bars correspond to 30 μm in the overview pictures (on the left) and to 10 μm when a higher magnification was applied (on the right)