RT Journal Article SR Electronic T1 Ultrastructural Descriptions of Pericyte/endothelium Peg-socket Interdigitations in the Microvasculature of Human Gastric Carcinomas JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 449 OP 453 VO 29 IS 1 A1 R.A. CARUSO A1 F. FEDELE A1 G. FINOCCHIARO A1 G. PIZZI A1 M. NUNNARI A1 G. GITTO A1 V. FABIANO A1 A. PARISI A1 A. VENUTI YR 2009 UL http://ar.iiarjournals.org/content/29/1/449.abstract AB Background: Angiogenesis requires complex multistep signalling pathways and a high degree of spatial and temporal coordination among endothelial cells and pericytes. The two cell types exhibit numerous contacts in vivo and in vitro, including the occurrence of peg-socket junctions. Materials and Methods: Ultrastructural findings in 9 cases of advanced gastric carcinomas were reviewed with special emphasis on endothelium/pericyte peg-socket junctions. Results: The incidence of peg-socket junctions was approximately 8% in 5 out of 9 cases. The remaining 4 cases showed a very low rate, including two cases in whom interactions were totally absent. Peg-socket junctions consisted of cytoplasmic projection from the pericyte protruding into the endothelial indentation. The endothelial cells interacting with pericytes showed ultrastructural signs of partial stabilization such as continuous endothelial lining, regularly constructed interendothelial junctions, more or less integrated pericytes, and multilayered basement membrane. Conclusion: Our ultrastructural study confirms previous reports regarding pericyte/endothelial peg-socket interdigitations in murine and human granulation tissues and extends these findings to the microvasculature of human gastric carcinomas. Copyright© 2009 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved