Ursolic acid could inhibit the growth of colon cancer cells and down-regulate of PKM2 protein expression in colon cancer cells in concentration manners. Key Word(s): 1. PKM2; 2. Immunohistochemistry; 3. MTT; 4. Western Blot; Presenting Author: YINGYING CUI Additional Authors: YUNSHENG YANG, MINGZHOU GUO, YUANMING PAN, YOUYONG LU Corresponding Author: YUNSHENG YANG, MINGZHOU GUO Affiliations: Chinese PLA General Hospital; Peking University Cancer Hospital Objective: HomeoboxA11 PI3K inhibitor (HOXA11) is a homeodomain-containing transcription factor. The aim of this study was to investigate epigenetic regulation

and the function of HOXA11 in human gastric cancer. Methods: Seven gastric cancer cell lines and 112 cases of primary gastric cancer samples were involved in this study. And semi-quantative RT-PCR, methylation specific PCR (MSP), Western Blot, immunohistochemistry, Oligo Microarray, MTT, Colony Formation RG-7388 cost Assay, dual-luciferase assay and Immunocytofluorescence staining technique

were employed to analyze the expression and the function of HOXA11 in gastric cancer. Results: HOXA11 expression was found in MGC803, SGC7901, MKN45, BGC823 and HGC27 cells. Loss of HOXA11 expression was found in AGS, and reduced expression was found in MGC803. Complete methylation of HOXA11 was found in AGS cells and partial methylation was found in MGC803 and SGC7901 cells. Unmethylation was found in MKN45, BGC823 and HGC27 cells. Loss of HOXA11 expression is correlated to promoter region completely methylation. Restoration of HOXA11 expression was induced by 5-AZA treatment. Above results suggest see more that HOXA11 expression was regulated by promoter region methylation. Sodium bisulfite sequencing conformed MSP results in AGS, SGC7901 and BGC823 cells. 81.25%

(91/112) of primary gastric cancer was methylated and no methylation was found in 5 cases of normal gastric mucosa. Methylation of HOXA11 is related to male gender (p < 0.05), tumor size (p < 0.05) and positive lymph node metastasis (p < 0.05). Lost or reduced HOXA11 expression was found in cancer significantly by comparing the expression of HOXA11 in 45 cases of available matched gastric cancer with adjacent tissue with IHC (P < 0.001). Cell proliferation, colony formation, cell migration and invasion were inhibited, apoptosis and G2/M arrest was induced after re-expression in AGS cell. Dual-luciferase assay microarray Analysis combined and western Blot demonstrated that Wnt signaling was inhibited by HOX11 up-regulting NKD1 gene expression. Conclusion: HOXA11 is frequently methylated in human gastric cancer and HOXA11 expression was silenced by promoter region hypermethylation. Wnt signaling was inhibited by HOX11 up-regulating NKD1 gene expression in gastric cancer. Key Word(s): 1. HOXA11; 2. DNA methylation; 3.