ABSTRACT
Objective:This study was performed using preclinical transplanted animal experiments to analyce the effects and mechanisms of third-generation EGFR-TKIs combined with anti-angiogenic therapy, thereby providing theoretical basis for further clinical trials. Methods:Researchers constructed the transplant BALB/C nude mice models with H1975 lung adenocarcinoma cell line (EGFR T790M) and divided the mice into four groups and treated them with osimertinib (2.5 or 5 mg/kg/day, gavage) alone or plus bevacizumab (5 mg/kg/twice weekly, i.p.) when the tumors reached approximately 0.4-0.6 cm3 in volume. The tumor growth curve of tumor volume was drawn according to the time in every group. After 2 weeks of treatment, the mice were killed and the tumors were processed for immunohistochemical staining and Western blot analysis. Immunostaining was performed to detect:HIF-1α, VEGF, and microvessel density (MVD) by using SP method on paraffin sections. Western blot analysis was used to analyze the protein expression levels of EGFR, AKT, and ERK signal transduction pathways. Results:After 2 weeks of treatment in high-and low-dose osimertinib alone, tumor volume in the high-dose group was significantly less than in low-dose osimertinib-alone group (P0.05). In the high-dose osimertinib-plus-bevacizumab group, tumor growth was not significantly greater than that in the high-dose osimertinib-alone group (P=0.642). No significant difference was observed in the above factors.In the high-and low-dose osimertinib-plus-bevacizumab groups, tumor volume and the above factors did not exhibit significant differences (P>0.05). Conclusion:Osimertinib has obvious antitumor effects in EGFR-mutant lung adenocarcinoma with T790M mutation cell xenografts. Bevacizumab has a synergetic inhibitory effect with osimertinib against EGFR-mutant lung adenocarcinoma with T790M mutation cell xenografts. Bevacizumab enhanced the antitumor effects of osimertinib by reducing VEGF expression and the microvascular density of the tumor, thereby improving the tumor microenvironment. Bevacizumab can enhance the effect of osimertinib by suppressing EGFR, ERK, and AKT phosphorylation, thereby synergistically inhibiting EGFR activation and downstream signaling.
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Aims To design and fabricate the 3 D cell cultural microfluidic chip for tumor cell culturing, with which to research the compatible conditions for gelatin forming and dissolving with calcium alginate as the scaffolds. To culture SMMC-7721 cells in the chip and to detect the surviving rate. Methods The microfluid-ic chip was fabricated with the software Corel Draw, the technology of soft lithography, molding, and plas-ma bonding. The applicability was tested and cells were cultured on it, on which the cell status was ob-served, their surviving rate was calculated with the help of the software IPP. Results The chip we fabri-cate was calculated is suitable for cell 3D culturing, the tumor cells showed a favorable proliferation ability in 72 h on chip, the surviving rate was ( 96. 1 ± 4. 5)%. The cells were solid and TCS appeared. Con-clusion The microfluidic chip manufactured appeared for tumor cell 3D culture, is suitable for the growth of SMMC-7721 and the cells are indubitable. They show some different status in proliferative and agminated compared with traditional 2D cell culture. With the chip and the condition found, there will be a better way to study the characteristics of tumor cells and is beneficial to the screen of anti-tumor drugs.
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Objective To investigate the microenvironment alteration in epithehiae-mesenchymce transition(EMT)metastasis in gastric carcinoma induced by transforming growth factor β(TGF-β). Methods The gastric carcinoma cell line NCI-N87 was treated with TGF-βto induce cells to undergone EMT,real-time quantitative PCR(RT-qPCR)and immunofluorescence staining were used to examine expression of EMT markers and wound-healing assays,and transwell migration and invasion assays were performed to determine the potential of cell migration and invasion. Further,alteration of cytokines in tumor microenvironment was detected using real-time quantitative PCR and ELISA. Moreover,the activity of its downstream signaling molecules was detected by Western blot. Results TGF-β induced gastric carcinoma cells NCI-N87 to undergone EMT as well as promote cell migration and invasion. Further,TGF-βinduced upregulation of epidermal growth foctor(EGF)and vascular endothelial growth facfor(VEGF)expression,as well as downregulation of Dickkopf-1(DKK1)and secreted frizzled receptor proein1(SFRP1),which activated PI3K/AKT and Wnt/β-catenin sequentially. Conclusion TGF-β promotes EMT by inducing microenvironment alteration in gastric carcinoma cell NCI-N87.
ABSTRACT
Objective: To investigate the microenvironment alteration in epithehiae-mesenchymce transitionEMT metastasis in gastric carcinoma induced by transforming growth factor βTGF-β.