Role of Renin-Angiotensin-System in Human Breast Cancer Cells: Is There a Difference in Regulation of Angiogenesis between Hormone-Receptor Positive and Negative Breast Cancer Cells?

This study examined the role of the RAS in human breast cancer cells to question if there are differences between HR-positive and HR-negative cells with regard to regulation of VEGF. Expression of different RAS components in hormone receptor (HR)-positive and HR-negative breast cancer cells was investigated using RT-PCR. Different stimulation protocols with different RAS inhibitors were used to investigate the effect on VEGF expression.

Nectin-2 in ovarian cancer: How is it expressed and what might be its functional role?

Nectin-2 is an adhesion molecule that has been reported to play a role in tumor growth, metastasis and tumor angiogenesis. Herein, we investigated Nectin-2 in ovarian cancer patients and in cell culture. Tumor as well as peritoneal biopsies of 60 ovarian cancer patients and 22 controls were dual stained for Nectin-2 and CD31 using immunohistochemistry.

Human chorionic gonadotropin controls luteal vascular permeability via vascular endothelial growth factor by down-regulation of a cascade of adhesion proteins.

Objective: To study the functional interactions of junctional proteins acting as regulators of vascular permeability in the human corpus luteum. We investigated the role of vascular endothelial (VE)-cadherin, nectin 2, and claudin 5 as controllers of vascular endothelial cell permeability.

Design: Performing immunohistochemical dual staining, we colocalized the above-mentioned proteins in the human corpus luteum.

VEGF induces ascites in ovarian cancer patients via increasing peritoneal permeability by downregulation of Claudin 5.

Objective: To evaluate the role of VEGF-dependent Claudin 5 production for the development of ascites via influencing endothelial permeability in peritoneal tissue of ovarian cancer patients.

Methods: This study investigates the mechanisms of formation of ascites in ovarian cancer patients, performing RT-PCR, VEGF-ELISA and immunohistochemical dual staining for CD31 and Claudin 5. In addition, in order to analyze the connectivity of VEGF, Claudin 5, and endothelial permeability, an endothelial cell/ovarian cancer cell-co-culture-system was established and evaluated performing Western blot analysis and a permeability assay.