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71.
目的优化人原代胰腺导管癌(PDAC)细胞及肿瘤相关成纤维细胞(CAFs)的分离及培养方法,验证CAFs对原代PDAC细胞的体外生长以及其对高度免疫缺陷模型NOG小鼠体内成瘤的影响,以探索人源性异种移植瘤(PDX)模型构建的新方法。方法首先原代培养手术切除的PDAC组织。以原代PDAC细胞单独培养为对照,观察CAFs和原代PDAC细胞共培养对PDAC细胞传代生长活性的影响。最后在NOG小鼠肩胛部注射混合培养的原代PDAC细胞和CAFs,观察PDX模型建模情况。结果原代PDAC细胞在体外单独培养传代少,均在5代及以内停止生长;与CAFs共培养可促进原代PDAC细胞生长活性,可稳定传至10代以上。NOG小鼠体内注射混合细胞(原代PDAC细胞+CAFs)建模2~3周即可形成肿瘤,而注射CAFs无肿瘤形成。混合细胞法建模有13例(92.9%)成瘤,单一细胞法有9例(64.3%)成瘤,可能因为样本量少,二者成瘤率比较差异无统计学意义(P=0.167);并且肿瘤细胞注射后2、4、6、8周时混合细胞法建模的肿瘤体积均明显大于对应观察时间点单一细胞法建模的肿瘤体积(P<0.01)。结论CAFs对原代PDAC细胞生长传代具有促进作用,原代PDAC细胞与CAFs共培养法可显著提高PDAC原代培养稳定传代,原代PDAC细胞与CAFs混合培养的细胞注射可提高NOG小鼠PDX建模成功率。 相似文献
72.
Objectives: Despite being commonly used as temporary cements in dentistry, there is a lack of studies regarding the cytotoxicity of zinc oxide-eugenol (ZOE) and zinc oxide non-eugenol (ZONE) cements. In addition, cytotoxicity evaluation of the materials often involves animal-based cells. Therefore, in this study, a cytotoxicity evaluation of commercially available ZOE and ZONE cements was carried out using both animal and human-based cells. Materials and methods. The extraction or dilution of the extraction from four commercially available cements (two zinc oxide-eugenol and two zinc oxide non-eugenol) was tested for cytotoxicity, using three different cells and a water-soluble treatzolium salt assay. The results were confirmed using a confocal laser microscope following calcein AM and ethidium homodimer-1 staining. Results. The results showed that there was a significant difference in cell viability depending on which cell was used, even when the same material was tested. Generally, L929 showed relatively low cell viability with a low EC50 (effective concentration of extracts that caused 50% of cell viability compared to the control) value compared to both HGF-1 and hTERT-hNOF. Such results were also confirmed by a confocal laser microscope. Conclusions. Careful consideration on interpreting the results for cytotoxicity evaluation of ZOE and ZONE cements is needed when different cells are used. 相似文献
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Peritoneal cell sheets composed of mesothelial cells and fibroblasts prevent intra‐abdominal adhesion formation in a rat model 下载免费PDF全文
Kunio Kawanishi Masayuki Yamato Ryouichi Sakiyama Teruo Okano Kosaku Nitta 《Journal of tissue engineering and regenerative medicine》2016,10(10):855-866
Postoperative intra‐abdominal adhesions remain an unsolved problem despite significant progress in the surgical procedures themselves. They often lead to small‐bowel obstruction, chronic abdominal and pelvic pain, as well as female infertility. The loss of mesothelial cells and several components of the inflammatory system following injury to the peritoneum results in fibrin formation and angiogenesis. The remaining fibrin matrix and angiogenesis lead to replacement by fibroblasts and fibrous band formation. The aim of this study was to develop a new therapeutic method of preventing intra‐abdominal adhesions. We fabricated transplantable peritoneal cell sheets from the rat peritoneum by cell sheet engineering using a temperature‐responsive culture system. The peritoneal cell sheets developed were composed of an upper monolayer of mesothelial cells and underlying multilayered fibroblasts, similar to the peritoneum in vivo. Transplantation of peritoneal cell sheets prevented tissue adhesion, fibrin deposition and angiogenesis, and, moreover, lymphangiogenesis and macrophage infiltration in a rat caecum cauterization adhesion model. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
78.
Péterszegi G Dagonet FB Labat-Robert J Robert L 《European journal of clinical investigation》2002,32(5):372-380
BACKGROUND: The importance of ascorbate on the production of extracellular matrix proteins (as elastin and collagens) is now well documented, but no studies have been published concerning its effects on fibronectin biosynthesis. Fibronectin is important for cell attachment and for proliferation. MATERIALS AND METHODS: The effects of Na ascorbate were investigated on cell attachment, proliferation, viability and fibronectin biosynthesis by human skin fibroblasts in vitro. Proliferation was followed by the monitoring of [(3)H]-thymidine incorporation; viability by the MTT-test, cell adherence by counting adherent and nonadherent cells and fibronectin biosynthesis by immunoprecipitation of biosynthetically labelled fibronectin. RESULTS: In the presence of ascorbate, the fibroblasts showed a biphasic growth pattern. At 500 microM ascorbate, [(3)H]-thymidine incorporation was stimulated by 15% as compared to the controls. Higher concentrations gradually decreased proliferation up to 36% of the control value at 5 mM. These effects of ascorbate on DNA synthesis were followed to > 1.25 mM by a strong inhibition, cytotoxic effect and cell death. The non-adherent cell count increased to 10% of the total population at 2.5 mM and to 31% at 5.0 mM ascorbate.Increasing concentrations of ascorbate resulted in a dose-dependent decrease of fibronectin biosynthesis, both in the culture supernates and cell extracts. This inhibition mainly concerned cell membrane-associated fibronectin.Superoxide-dismutase or catalase could inhibit Na ascorbate-induced cytotoxicity and partially re-establish fibronectin biosynthesis. Desferrioxamine, ergothionein and vitamin E were inefficient. CONCLUSIONS: Our results indicate that ascorbate decreases fibronectin biosynthesis of cultured human skin fibroblasts, thereby producing cell detachment and decreased proliferation. This effect is mainly mediated by the reactive oxygen species and can be inhibited by superoxide-dismutase and catalase. 相似文献
79.
Ying-Yu Nan Wen-Jun Zhang De-Hong Huang Qi-Ying Li Yang Shi Tao Yang Xi-Ping Liang Chun-Yan Xiao Bing-Ling Guo Ying Xiang 《World Journal of Clinical Cases》2021,9(18):4585-4598
BACKGROUNDDiffuse large B-cell lymphoma (DLBCL) is a common non-Hodgkin lymphoma. The development of immunotherapy greatly improves the patient prognosis but there are some exceptions. Thus, screening for better biomarkers for prognostic evaluation could contribute to the treatment of DLBCL patients.AIMTo screen the novel mediators involved in the development of DLBCL.METHODSThe dataset was applied to identify the differentially expressed genes (DEGs) in DLBCL, and the principal components analysis plot was used to determine the quality of the included samples. The protein-protein interactions were analyzed by the STRING tool. The key hub genes were entered into to the GEPIA database to determine their expressions in DLBCL. Furthermore, these hub gene alterations were analyzed in cBioportal. The UALCAN portal was employed to analyze the expression of the hub genes in different stages of DLBCL. The Estimation of Stromal and Immune cells in Malignant Tumor tissues using Expression data Score was conducted to evaluate the correlation between the gene expression and tumor purity. The gene-gene correlation analysis was conducted in the GEPIA. The stromal score analysis was conducted in TIMER to confirm the correlation between the gene expression and infiltrated stromal cells. The correlation between the indicated genes and infiltration level of cancer-associated fibroblasts (CAFs) was also completed in TIMER with two methods, MCP-Counter and Tumor immune dysfunction and exclusion. The correlation between fibronectin (FN1) protein level and secreted protein acidic and cysteine-rich (SPARC) messenger ribonucleic acid expression was confirmed in the cBioportal.RESULTSThe top 20 DEGs in DLBCL were identified, and the principal components analysis plot confirmed the quality of the significant DEGs. The pairwise correlation coefficient analysis among all samples showed that these DEGs have a certain co-expression pattern. The DEGs were subjected to STRING to identify the hub genes, alpha-2-macroglobulin (A2M), cathepsin B (CTSB), FN1, matrix metallopeptidase 9 (MMP9), and SPARC. The five hub genes were confirmed to be overexpressed in DLBCL. The cBioportal portal detected these five hub genes that had gene alteration, including messenger ribonucleic acid high amplification and missense mutation, and the gene alteration percentages of A2M, FN1, CTSB, MMP9, and SPARC were 5%, 8%, 5%, 2.7%, and 5%, respectively. Furthermore, the five hub genes had a potential positive correlation with tumor stage. The correlation analysis between the five genes and tumor purity confirmed that the five genes were overexpressed in DLBCL and had a positive correlation with the development of DLBCL. More interestingly, the five genes had a significant correlation with the stromal infiltration scores. The correlation analysis between the fives genes and CAFs also showed a significant value, among which the top two genes, FN1 and SPARC, had a remarkable co-expression pattern.CONCLUSIONThe top DEGs were identified, and the five hub genes were overexpressed in DLBCL. Furthermore, the gene alterations were confirmed and the positive correlation with tumor purity revealed the overexpression of the five genes and close association with the development of DLBCL. More interestingly, the five genes were positively correlated with stromal infiltration, especially in CAFs. The top two genes, FN1 and SPARC, showed a co-expression pattern, which indicates their potential as novel therapeutic targets for DLBCL. GSE60相似文献
80.
Anke Ruedel Peter Dietrich Thomas Schubert Simone Hofmeister Claus Hellerbrand Anja Katrin Bosserhoff 《International journal of clinical and experimental pathology》2015,8(6):6607-6616
Activated synovial fibroblasts in rheumatoid arthritis (RASF) play a critical role in the pathology of rheumatoid arthritis (RA). Recent studies suggested that deregulation of microRNAs (miRs) affects the development and progression of RA. Therefore, we aimed to identify de-regulated miRs in RASF and to identify target genes that may contribute to the aggressive phenotype of RASF. Quantitative real-time PCR revealed a marked downregulation of miR-188-5p in synovial tissue samples of RA patients as well as in RASF. Exposure to the cytokine interleukine-1β lead to a further downregulation of miR-188-5p expression levels compared to control cells. Re-expression of miR-188-5p in RASF by transient transfection significantly inhibited cell migration. However, miR-188-5p re-expression had no effects on glycosaminoglycan degradation or expression of repellent factors, which have been previously shown to affect the invasive behavior of RASF. In search for target genes of miR-188-5p in RASF we performed gene expression profiling in RASF and found a strong regulatory effect of miR-188-5p on the hyaluronan binding protein KIAA1199 as well as collagens COL1A1 and COL12A1, which was confirmed by qRT-PCR. In silico analysis revealed that KIAA1199 carries a 3’UTR binding site for miR-188-5p. COL1A1 and COL12A1 showed no binding site in the mRNA region, suggesting an indirect regulation of these two genes by miR-188-5p. In summary, our study showed that miR-188-5p is down-regulated in RA in vitro and in vivo, most likely triggered by an inflammatory environment. MiR-188-5p expression is correlated to the activation state of RASF and inhibits migration of these cells. Furthermore, miR-188-5p is directly and indirectly regulating the expression of genes, which may play a role in extracellular matrix formation and destruction in RA. Herewith, this study identified potential novel therapeutic targets to inhibit the development and progression of RA. 相似文献