Effect Of Endogenous NO On Expression Of HDAC4 In Hepatocellular Carcinoma Model In Nude Mice

Obejective:To investigate the effect of endogenous NO on the expression of HDAC4 in Hepatocellular carcinoma model in nude mice, and to explore the new antitumor ideas.Methods:Section tissues came from the established hepatocellular carcinoma mode in nude mice:4-5 weeks BALB/c nude mice of male were randomized into three groups:control group (intraperitoneal injection of 0.2ml saline),5-FU group (intraperitoneal injection of 20 mg·kg-15-FU),5-FU+L-Arg group(intraperitoneal injection of 20 mg·kg-15-FU+100mg·kg-1L-Arg). The necrotic degree and range were observed by the microscope. The expression of iNOS and HDAC4 were detected by immunohistochemistry.According to the percentage of the necrotic part in the tissue slice, four levels are divided:≤25%(+),25%-50%(++), 50%-75%(+++),> 75%(++++). According to the method of Mattern to determine the expression of iNOS and HDAC4, did not see the dying as 0 point, mild dying (yellow) for 1 point, moderate dying (tan) for two points, depth dying (tan) for three points;Positive cells percentage:no the dying cell 0 point, dyeing cells<25% for 1 point,25%-50% for two points,> 50% for three points. The scoring summarizations 0 point are divided into negative,1-2 points are divided into weak positive (+),5-6 points are divided into strong positive (+++),3-4 points between two composes (+ +). Using SPSS13.0 statistical software for the statistical analysis, Rank sum test was adopted for the degree of tumor tissue necrosis, the expression of iNOS and HDAC4 in the three groups, Spearman related test was adopted for analyzing the relation between iNOS and HDAC4 expression in the three groups.Results:1. Changes in nude transplantation tumor pathologicalThere were more fibers of different thicknesses tissues in nude transplantation tumor observated by microscope, which divided cancer cells into nests, some of which are lumens shape arrangement. There were more blood sinus structure were visible. Most cancer cells were triangles and their cytoplasm is rich, the nucleus shape highly rules, the size of slurry ratio increases, nuclear fission in pathology were visible. Drug treatment in different degree of tumor tissue necrosis, the control group 5cases (+),4cases (++), lease (+++); 5-FU group in 4cases (++),4cases (+++),2cases (++++);5-FU+L-Arg group 2cases (++),3cases (+++),5cases (++++),5-FU group,5-FU+L-Arg group and control group had significant difference (P<0.05).2. The expression of iNOS and HDAC4 detected by immunohistochemistry SPiNOS was expressed as thick or thin particles exsiting in the tumor cell cytoplasm, parts of expression in cell membranes. The expression of iNOS in contronl group,5-FU group and 5-FU+L-Arg group was increasing, the difference in each group was significent (P<0.05). HDAC4 diffuses express the tumor cells cytoplasm and or nuclei, mesenchymal cells are visible expression. The expression of iNOS in contronl group,5-FU group and 5-FU+L-Arg group was decreasing, the difference in each group was significent (P<0.05)3. The correlation analysis results of the expression of iNOS and HDAC4By Spearman rank correlation analysis shows that, the expression of iNOS and HDAC4 in the control group had no significant correlation, but in 5-FU group and 5-FU+L-Arg group had negative correlation.Conclusion:①The increasement of necrosis degree and range in nude transplantation tumor tissue and drugs have obvious relationship.②The endogenous NO could cut the expression of HDAC4 in Hepatocellular carcinoma model in nude mice, the expression of iNOS enhanced, the concentration of endogenous NO increased, the expression of HDAC4 significantly weakened.③In tumor cells NO and HDACs had new relations, NO was the important regulators for HDACs in the multiple functions, which provideds new ideas for our studies of tumor therapy.