To explore the roles of TF, we used stable transfect antisense TF (anti-TF) technology to silence TF in gastric cancer cell line SGC7901 with high level expression of TF and detection antitumor effects in vitro and in vivo. Methods: Antisense TF designed for human TF was stable transfected into SGC7901 cells. The expression of TF was detected by reverse transcription PCR and western blot. STA-9090 in vivo Cell proliferation was measured by MTT assay. Cell apoptosis was assessed by flow cytometry. The metastatic potential of SGC7901 cells was determined by wound healing, transwell assays. In vivo the effect of anti-TF on the

growth of gastric cancer xenografts in nude mice was detected. Results: Anti-TF can reduced the TF expression mRNA and protein in the SGC7901 cells. Reduce the TF in SGC7901 cells resulted is suppression of cell proliferation, invasion and metastasis induced cell apoptosis. Intratumoral injection of stable transfec anti-TF gastric cancer cells suppressed the tumor growth in vivo model of gastric cancer. Conclusion: Inhibited of the TF using antisense could provide a potential

approach for gene therapy against gastric cancer. Key Word(s): 1. check details gastric cancer; 2. tissue factor; 3. gene therapy; Presenting Author: BIN WANG Additional Authors: DONGFENG CHEN Corresponding Author: BIN WANG Affiliations: Department of Gastroenterology, Daping Hospital, Third Military Medical University, Chongqing, China Objective: Cancer stem cell (CSC) was proposed to fuel the malignant and metastatic growth gastric cancer (GC), one of the most common malignancies of the digestive tract. However, the identity of this critical subpopulation of GC cells in primary human gastric cancers remains elusive Methods: we show that Lgr5, a well-established stem cell marker of the gastrointestinal epithelium, was expressed in GC tissue

Results: Using an optimized culture system for pyloric gland stem cells, Lgr5 was demonstrated to identify tumorsphere initiating GC MCE公司 cells that showed extensive self-renewing ability. Lgr5+ cells were endowed with multilineage potential both in vitro and in vivo, even at single cell level. Lgr5+ cells enriched robust tumor initiating capacity which could be maintained upon serial transplantation in NOD/SCID mice. Importantly, knockdown of Lgr5 attenuated self-renewal of tumorigenicity of gastric CSC, through a mechanism involving downregulation of Wnt/β-catenin signaling Conclusion: These results provided evidences for the first time that Lgr5 marked and sustained self-renewing and tumor propagating cells in GC, which might facilitate development of novel therapeutic modalities for GC. Key Word(s): 1. Gastric Cancer; 2. Cancer Stem Cells; 3. Lgr5; 4.