Study About The Role Of HMGB1in Angiogenesis Of Ovarian Cancer

Invasion and metastasis are the main cause of death in patients with malignanttumors, angiogenesis plays a key role in the invasion and metastasis, it is currentlyknown that vascular endothelial growth factor (VEGF) is the strongest vascularpermeability agents, it not only leads to malignant ascites or tumor stromal edema,but also leads to plasma protein, fibrinogen, liquid leakage through the bloodvessels, causes changes in the extracellular matrix, promots angiogenesis and newmatrix formation, is an important growth factors associated with malignant tumorinvasion metastasis and ascites formation.High mobility group protein B1(HMGB1) is a nuclear DNA-binding protein，is released by necrotic cells, induce inflammation, promote tissue repair andangiogenesis. Because HMGB1can induce vascular endothelial cell growth,migration and sprout and it is defined as the pro-angiogenic growth factor. HMGB1-induced cell migration requires activation of the classical and non-classical NF-κBpathway, which can lead to CXCL12gene transcription. HMGB1can also protectCXCL12from degradation, induce extra CXCL12secretion.CXCL12play an important role in angiogenesis, CXCL12up-regulates theexpression of VEGF and VEGF up-regulates the expression of CXCL12,CXCR4-CXCL12and VEGF have synergistic effect in promoting the process ofblood vessels. HMGB1and CXCL12form a heterocomplex, which promoterecruitment of inflammatory cells through CXCR4signaling pathways.Therefore, we detect the expression of HMGB1influence vascular endothelialgrowth factor VEGF, chemokines12（CXCL12）to understand whether HMGB1expression have an effect on angiogenesis in ovarian cancer. We study themechanisms of angiogenesis in ovarian cancer. Part I The expression of HMGB1，VEGF，CXCL12in ovarian cancerObjectiveThe expression of HMGB1，VEGF，CXCL12are detected in ovarian cancerMethodsSelect54cases have been diagnosed with epithelial ovarian cancer patients，control group for the same period due to other diseases gynecological surgicalremoval of normal ovarian tissue samples20cases. The expression of HMGB1,CXCL12and VEGF are assayed by immunohistochemical staining in ovarian cancer.ResultsHMGB1express in cancer cells and stromal cells in the cytoplasm and nucleus,with pale yellow to brown granules; CXCL12express in cancer cells and stromalcells cytoplasm, with pale yellow to brown granules; VEGF express in cancer cellsand stromal cells in the cytoplasm, with pale yellow to granules.ConclusionThe expression of HMGB1, VEGF and CXCL12are associated with lymph nodemetastasis in ovarian cancer tissues.Part II HMGB1expression in SKOV3, HUVECs cellsObjectiveThe expression of HMGB1are detected in SKOV3and HUVECs cells.MethodsExtracting total proteins, plasma proteins and nuclear proteins from SKOV3andHUVECs cells, Western blot detect the expression of HMGB1.ResultsHMGB1exist in SKOV3and HUVECs cells. But it is higher in SKOV3cellsthan HUVECs.The expression of HMGB1in SKOV3cells is significantly higherthan HUVECs in cytoplasm.(P=0.009) The expression in nucleus also is the sameresult,(P=0.000) The expression of HMGB1in nucleus is significantly higher than incytoplasm in SKOV3cells.(P=0.000) The expression of HMGB1in nucleus issignificantly higher than in cytoplasm in HUVECs cells.(P=0.026)Conclusion The expression of HMGB1exist in SKOV3and HUVECs cells, HMGB1playsan important role in the cytoplasm or nucleus.Part III The expression of HMGB1in angiogenesis and mechanism inSKOV3cellsObjectiveTo investigate the role of HMGB1in angiogenesis and mechanism in SKOV3cellsMethodsThe HMGB1eukaryotic expression plasmid and synthetic gene for siRNAHMGB1transfect SKOV3cells, by Western blot analysis after transfection thechange of HMGB1, CXCL12, VEGF expression, flow cytometry detect apoptosis.ResultsAfter transfecting the over-expression of HMGB1eukaryotic expression plasmidDNA in SKOV3cells, SKOV3apoptosis reduce, while the synthetic gene for siRNAHMGB1transfect SKOV3cells, The expression of HMGB1, CXCL12and VEGFdecrease, SKOV3apoptosis increase compared with the control group. Differencewas statistically significant (P <0.05)ConclusionHMGB1directly affect the fall of CXCL12, VEGF and HMGB1.It is associatedwith apoptosis of SKOV3cells.