In the current study, we demonstrated 5-Fluoracil mw that TGF-β1 was able to induce Smad 2 and 3 phosphorylation in HPMCs. These data indicated that rapid and sustained phosphorylation

of Smad 2 and Smad 3 may participate in TGF-β1-induced peritoneal fibrosis. Many studies have investigated the impact of the cancer-stroma interaction in different human cancers and shown the importance of tumor cell interaction with extracellular matrix to establish a favorable microenvironment for tumor cell growth, invasion, and metastasis [18, 29, 30]. Our data from the current study confirmed such an interaction, in that TGF-β1 secreted by gastric cancer cells was able to increase production of fibronectin and collagen III in HPMCs and in turn induce peritoneal fibrosis. TGF-β1-treated mesothelial cells affected gastric cancer cell adhesion. We also determined whether these effects are ECM-dependent by using RGD to achieve selective and specific knockdown of minimal sites of ECM cell binding Opaganib nmr domain. We found that RGD treatment significantly decreased the adhesive ability of cancer cells to mesothelial cells. These

data suggest that peritoneal fibrosis may stimulate the adherence capability of gastric cancer cells to the peritoneum, which is consistent with previous reports showing that TGF-β1 enhanced tumor-mesothelial cell adhesion [31, 32]. We have also noticed that the concentration of TGF-β1 in the peritoneal wash fluid was lower than that to use in vitro to treat mesothelial cells. It may the natural differences between in vivo and in vitro experiments and the latter is acute and artificial. In addition, some other factors secreted by gastric cancer cells may also contribute to the effect. In conclusions, our current study characterized the interaction of gastric cancer with peritoneal fibrosis and determined that TGF-β1 plays a key role in induction of peritoneal fibrosis, which in turn affected gastric cancer adhesion and metastasis. Furthermore, the pretreatment of cancer DCLK1 cells with RGD significantly inhibited the adhesion of carcinoma cells. Taken together, our current

data demonstrated that the presence of peritoneal fibrosis appears to provide a favorable environment for dissemination of gastric cancer. Acknowledgements This study was supported by National Natural Science Foundation of China(No.30873043, 30901419 and 81071956). We thank Prof. Feng Li for technical assistance and MD. Jiamei Wu, Dr. Chunyu Wang, Dr. Qiang Ke, Dr. Jian Zhang and Dr. Shuo Wang for precious advice. References 1. Paul L, Emad M: Gastric cancer. Br Med Bull 2008, 85: 87–100.CrossRef 2. Kamangar F, Dores GM, Anderson WF: Patterns of cancer incidence, mortality, and prevalence across five continents: Defining priorities to reduce cancer disparities in different geographic regions of the world. J Clin Oncol 2006, 24: 2137–2150.PubMedCrossRef 3. Parkin DM, Bray F, Ferlay J, Pisani P: Global cancer statistics 2002. CA Cancer J Clin 2005, 55: 74–108.PubMedCrossRef 4.