Interleukin-6 and transforming growth factor-β synergistically stimulate chondrosarcoma cell proliferation

✍ Scribed by Pierre-André Guerne; Martin Lotz

• Publisher: John Wiley and Sons
• Year: 1991
• Tongue: English
• Weight: 909 KB
• Volume: 149
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1041490115

✦ Synopsis

This study examines the regulation of Swarm rat chondrosarcoma (SRC) cell proliferation in vitro. In serum-free cultures, SRC cells showed only transient DNA synthesis and this was increased by serum. Transforming growth factor-p (TGF-p) was identified as an essential serum component, since the mitogenic effect of sera was related to their TGF-p content and neutralized by antibody to TGF-p.

Among a large panel of agents tested, TGF-P was the only factor that stimulated proliferation in serum-free media. The TGF-P isoforms TGF-PI and TGF-pZ induced similar dose-dependent increases with maximal 62.5-fold stimulation at 10 ngiml.

Interleukin-6 (IL-6) was identified as a new factor that stimulated SRC proliferation. IL-6 effects were serum-dependent and their magnitude correlated with the TGF-P content in different serum preparations. In serum-free cultures where IL-6 by itself had no detectable effect it caused up to 7.6-fold increased proliferation in the presence of small doses of TGF-P (0.01-0.1 ngiml). This synergy was unique, since no other factor tested synergired with IL-6 or TGF-P. In examining potential mechanisms for this synergy it was found that TGF-P increased IL-6 receptor expression.

In summary, these results identify IL-6 as a new and TGF-P as the most potent growth factor for chondrosarcoma cells and describe novel interactions between these factors in the regulation of cell growth.