ABSTRACT
<p><b>OBJECTIVE</b>To detect miR-200a expression in human colorectal carcinnoma (CRC) cell lines and explore the role of miR-200a in regulating the biological behavior of CRC cells.</p><p><b>METHODS</b>Real-time quantitative RT-PCR (qRT-PCR) was used to detect miR-200a expression levels in 6 CRC cell lines (HCT116, HT29, LS174T, SW480, SW620 and LoVo). miR-200a mimics were transiently transfected into LoVo, and the changes in cell proliferation, apoptosis, migration, and cell-cell adhesion were assessed using CCK-8 assay, TUNEL assay, transwell migration assay, and homogenous adhesion experiment, respectively.</p><p><b>RESULTS</b>The expression of miR-200a was down-regulated in the 6 CRC cell lines, among which the highly metastatic LoVo cell line showed the lowest expression and the tumorigenic but non-metastatic CRC cell line HCT116 had the highest expression. Overexpression of miR-200a depressed cell proliferation and migration but promoted cell apoptosis and cell-cell adhesion in LoVo cells.</p><p><b>CONCLUSION</b>miR-200a plays a role in regulating the invasiveness and metastasis of CRC, and overexpression of miR-200a causes a significant reduction of cell proliferation and migration and promotes apoptosis and cell-cell adhesion in LoVo cells.</p>
Subject(s)
Humans , Apoptosis , Cell Line, Tumor , Cell Proliferation , Colorectal Neoplasms , Metabolism , Down-Regulation , Gene Expression Regulation, Neoplastic , MicroRNAs , Metabolism , TransfectionABSTRACT
Objective To establish a double-antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA) for the rapid detection of germ tube-specific antigens of Candida albicans,and to evaluate its specificity and sensitivity.Methods A DAS-ELISA was established with the monoclonal antibody McAb03.2C1-C2 as the primary antibody,and horseradish peroxidase (HRP) labeled McAb03.2C1-C2 as the secondary antibody.The established assay was used to detect germ tube-specific antigens of Candida albicans in sera from 5 patients with systemic Candida albicans infection and from 6 rabbit models at 12,24,48,72hours,on week 1,2 after infection with Candida albicans.Results A good liner relationship was observed between the absorbance value at 495 nm and antigen concentrations when the titer of McAb03.2C1-C2 was 1 ∶ 4000 and the concentration of coated antigen varied from 1.25 to 40 μg/ml.The specificity and sensitivity of the DAS-ELISA were 95％ and 92％ respectively in the detection of germ tube-specific antigens in the rabbit models.The results of detection with DAS-ELISA in serum specimens from the patients were consistent with those with the routine method.Conclusions A DAS-ELISA is primarily established for the rapid detection of germ tube-specific antigens of Candida albicans,and has shown a satisfactory sensitivity and specificity in the animal model experiment.
ABSTRACT
Background and purpose:CD4+CD25+ regulatory T (Treg) cells are an important naturally accruing subpopulation of regulatory T cells. They not only prevent the spontaneous emergence of autoimmune diseases and contribute to the establishment of dominant tolerance on allogeneic transplantation, but also play an essential role in the generation, development and immunotherapy of many different kinds of malignant tumors. We studied the expression of CD4+CD25+ regulatory T cells(Tregs) in colorectal cancer patients and its significance. Methods:The tissues of tumors and counterpart normal tissue of 30 colorectal cancer patients were collected, the proportion of CD4+CD25+ Tregs as the percentage of the total CD4+ T cells were analyzed using flow cytometry and immunohistochemistry.Results:Compared with counterpart normal tissue(5.5?1.3)%, the percentage of CD4+CD25+ Tregs in tumor tissues was significantly higher (24.1?4.8)%(t=5.155,P=0.002). The proportion of CD4+CD25+ Tregs in the patients with lymph nodes metastasis was (27.9?3.6)% which was significantly higher than that in patients without lymph nodes metastasis[(20.3?1.3)% (t=3.489,P=0.025)].Conclusions:The proportion of CD4+CD25+ Tregs in tumor tissues of colorectal cancer patients was significantly increased, and they may play an essential role in the development of colorectal cancer.