Sodium Nitrite Improves Epithelial-mesenchymal Transition Of Hepatoma Cells In Mice Bearing H22

Objective This study is to determine the effect of sodium nitrite on the epithelial-mesenchymaltransition in hepatoma cells in mice bearing H22,and also to the role of hypoxiainducible factor1α(HIF-1α) and oxygen species (ROS) in this process.Methods (1) Mice hepatocarcinoma cell line H22were inoculated subcutaneously into rightaxillary of sixty male Kunming mice and then randomly divided into four groups: controlgroup;low-dose sodium nitrite group (10mg·kg1); medium-dose sodium nitrite group (20mg·kg1);high-dose sodium nitrite group (30mg·kg1). The mice of sodium nitrite groups were given (ig)sodium nitrite with1030mg·kg1·d1for20days. The mice were killed on the21st day.Hematoxylin-eosin staining were used to observe the pathology change of the xenografts;Immunohistochemistry、immunofluorescence and Western blotting were used to test the related proteinexpression; Colorimetric method was employed to determine the the activity of superoxide dismutase(SOD) and catalase (CAT) in serum and the xenograft tissue; Colorimetric method was also used tomeasure the levels of the malondialdehyde (MDA) and nitrite in serum and the xenograft tissue.(2)Mice hepatocarcinoma cell line H22were inoculated intraperitoneally into abdomen of thirty maleKunming mice and then randomly divided into two groups: The mice of sodium nitrite group were given(ig) sodium nitrite with30mg·kg1·d1every day; The mice of control group were given equal volumesaline, Abdominal circumference of the mice was measured every other day and the survival time of themice was recorded.Results Compared with control group, there was no obvious difference between the two groups inthe volume or weight of xenografts, while pulmonary metastasis rate significantly increased, withdissection through adjacent fascia and skeletal muscle. Immunohistochemistry、immunofluorescenceand western blotting showed that the expression of Vimentin was enhanced, E-cadherin declined,tumor cells presented epithelial-mesenchymal transition.With the increase of nitrite dosage, nitritecontents in serum and tissue gradually increased. The activity of SOD and CAT decreased, and thelevels of MDA increased in the tumor tissue, while there are no differences of these indicators inserum. The expression of HIF-1α was enhanced, which was confirmed by immunohistochemistry and Western blotting. In the experiment of H22ascites tumor found that ascites condition of sodium nitritetreatment group was more serious than that of the control group; Survival time was significantlyshortened.Conclusions1. Sodium nitrite can improve the epithelial-mesenchymal transition of the xenografts in mice bearingH22.2. Sodium nitrite treatment can improve the epithelial-mesenchymal transition, which might relate to thefact that ROS mediated signal pathway increased the expression of HIF-1α.3. Sodium nitrite lavage can significantly shorten the survival time of the H22burdening tumor mice inascites style.