TGF-β1 is the factor secreted by proliferative chondrocytes to inhibit neo-angiogenesis

• Published in: Journal of cellular biochemistry 2001, Vol.81 (S36), p.79-88
• Main Authors: Wing-hoi, Cheung, Kwong-man, Lee, Kwok-pui, Fung, Pauline, Lui Po-yee, Kwok-sui, Leung
• Format: Article
• Language: English
• Subjects: anti-angiogenesis; chondrocytes; endothelial cells; growth plate; TGFβ1
• ISSN: 0730-2312; 1097-4644
• DOI: 10.1002/jcb.1079

Growth plate is an avascular tissue, which has been reported to be capable of retarding tumor spread. It is believed that angiogenic inhibitor(s) exist to inhibit the neo‐vascularization of tumor, thus impeding the tumor growth. In this study, growth plate chondrocyte‐derived TGFβ1 was identified to be anti‐angiogenic. It was found that growth plate chondrocytes (GPC) secreted TGFβ1 mostly in latent form as demonstrated by gel filtration and immunoblotting. Enzyme‐linked immunosorbent assay (ELISA) was followed to quantify TGFβ1 in GPC conditioned medium (CM), in which 866 pg/ml of TGFβ1 was found. Besides, the angiogenesis inhibitory effect of GPC CM was abolished by the addition of anti‐TGFβ1 antibody in the in vitro culture system and the in vivo chick chorioallantoic membrane (CAM) assay. This confirmed the anti‐angiogenic properties of chondrocyte‐derived TGFβ1. TGFβ1 was expressed predominantly in the proliferative zone of porcine growth plate. This explains the low incidence of tumor invasion across the entire growth plate. Also, this helps to explain the observation that tumor invasion across the physis increases with age as the proliferative zone gradually disappears. J. Cell. Biochem. Suppl. 36: 79–88, 2001. © 2001 Wiley‐Liss. Inc.