The Effects Of Hyperbaric Oxygen Induced Cell Cycle Or Combined With Chemotherapy On The Proliferation Of Colon Adenocarcinoma Cells

[Background]Chemotherapy is clinically used to treat patients with malignant tumors, but its therapeuticeffect can not be satisfied. The reasons may related to the following factors:①tumor cells getmultidrug resistance (MDR);②chemotherapy produces poisonous sideeffect;③tumor cellswere heterogeneous[13],and so on. The present studies suggest that the main cause werehypoxia of the part cells of solid tumor and heterogeny of tumor tissues for the resistance oftumor cells to radiotherapy and chemotherapy. Hypoxia induces the resistance of tumor cells[4];and the heterogeny of solid tumors result in the appearance of subpopulations of differentproliferative potency in the same tumor tissue, so that the target cells sensitive to cell cyclespecific drug are reduced. Therefore, improved ventilation of tumor tissue could make tumorcells acquire abundant oxygen, which enhanced the sensibility of tumor cells to radiotherapyand chemotherapy [5]? Furthermore, synchronization of cells can effectively increase the impactof chemotherapy. Hyperbaric oxygen (HBO) has widely been applied to clinic as therapeuticand adjunant therapy, however, whether HBO could be used to treat tumors, and if so, how toenhance the sensibility and reduce the sideeffectof chemotherapy, still to be furtherexplored.[Objective]①To study the effects of HBO on the cell cycle of colon adenocarcinoma；②To explore the effects of HBO combined with chemotherapy drug(5FU)on the proliferation of colon adenocarcinoma cells；③To investigate the expression of HBO on Hypoxiainducible factor 1(HIF1)mRNA and Vascular endothelial growth factor(VEGF)mRNA of colon adenocarcinoma cells.[Materials and Methods]①There are three kinds of cancer cells of human LoVo,SW480 and CaCo2,exposed to HBO separately, pressure of HBO is 0.10, 0.15, 0.20 and 0.25 MPa and oxygenconcentration is 8.4% (normal oxygen) and 95%;②Examined the cell cycle of cancer cells under thedifferent pressure of HBO and the different time after HBO exposed with flow cytometry;③Observed thelethal effect of HBO combined with chemotherapy(5FU) under 0.20MPa HBO and after 24h by MTT;④Examined the expression of HIF1αand VEGF mRNA with RTPCR after HBO exposure.[Results]...