BACKGROUNDDecorin is a member of the small proteglycans in extracellular matrix of tumor microenvironment, which is known to relate to the initiation, progression and growth of the tumor. The aim of this study is to investigate the effects and mechanism of decorin on the proliferation of A549 lung adenocarcinoma cell line in vitro.

METHODSLung adenocarcinoma cell line A549 was cultured with decorin in a wide range of concentration for different time. Cell activities were studied by MTT. The changes of cell cycle and apoptosis were analyzed by FCM. Decorin mRNA expression was detected by RT-PCR. P21 expression was determined by Western blot. TGF-β concentration in the culture supernatants was determined by ELISA.

RESULTSThe proliferation of A549 cell could be inhibited by decorin in vitro and the inhibition effect was the time- and dose-dependent relationship. Apoptosis of adenocarcinoma cell could be efficiently induced by decorin in a time/dose-dependent manner. Decorin could upregulate the intrinsic decorin mRNA and P21 protein expression, downregulate the TGF-β, and block cell cycle at G1 phase.

CONCLUSIONSDecorin can inhibit adenocarcinoma cell proliferation and induce apoptosis of adenocarcinoma cells in vitro. The proliferation of A549 cell could be inhibited in vitro by decorin through the mechanism of increasing decorin mRNA, decreasing TGF-β, increasing P21 protein expression, inhibiting cell cycle and inducing cell apoptosis.