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In this study, a method called bispecific CEAScFv-streptavidin fusion protein-based immuno-PCR technique will be tested experimentally. The application of the bispecific fusion protein-based immuno-PCR technique has the significant advantage that it can be readily applied in the clinical setting, as well as tested as a potential screening tool in high-risk populations of certain types of cancer.

To detect the blood genomic DNA methylation in coke oven workers and find a possible early screening index for occupational lung cancer, 74 coke oven workers as the exposed group and 47 water pump workers as the controls were surveyed, and urine samples and peripheral blood mononuclear cells (PBMCs) were collected. Airborne benzo[a]pyrene (B[a]P) levels in workplace and urinary 1-hydroxypyrene (1-OH-Py) levels were determined by high-performance liquid chromatography. DNA damage of PBMCs and the p14(ARK), p15(INK4b) and p16(INK4a) gene CpG island methylation in the promoter region were detected by comet assay and methylation-specific polymerase chain reaction techniques, respectively. Results show that compared with the controls, concentration of airborne B[a]Ps was elevated in the coke plant, and urinary 1-OH-Py’s level and DNA olive tail moment in comet assay were significantly increased in the coke oven workers, and p14(ARK), p15(INK4b) and p16(INK4a) gene methylation rates were also significantly increased. With the working years and urinary 1-OH-Py’s level, the rates of p14(ARK) and p16(INK4a) gene methylation were significantly increased while that of p15(INK4b) gene methylation displayed no statistical change. We conclude that PBMCs’ p14(ARK) and p16(INK4a) gene methylation may be used for screening and warning lung cancer in coke oven workers. [ABSTRACT FROM AUTHOR]

Background: The sensitivity of conventional cytology for the detection of tumor cells in pleural effusion (PE) is inadequate. Mucine 1 (MUC1) and epithelial cell adhesion molecule (EpCAM) are two frequently and intensely expressed tumor-associated antigens in malignancies of epithelial origin.Objective: To evaluate the diagnostic value of pleural fluid MUC1 and EpCAM mRNA in differentiating benign and malignant PE.Method: Fifty-eight patients with malignant PE and 40 patients with benign PE were included in this study. Pleural fluid MUC1 and EpCAM mRNA levels were measured by quantitative real-time PCR. Carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (Cyfra21-1) were also detected simultaneously. The receiver operating characteristic (ROC) curves were constructed to assess diagnostic performance of the four tumor markers in PE.Results: For the diagnosis of malignant PE, MUC1 and EpCAM mRNA had larger area under ROC curves (0.916 and 0.922) and higher sensitivity (67.2 and 70.7%) with the same specificity, when compared with CEA and Cyfra21-1 (0.821 and 0.780; 48.3 and 44.8%, respectively). By combining cytology with MUC and EpCAM, a positive result indicating the presence of malignancy was achieved in 87.9%, with a good specificity of 95%.Conclusions: Compared with CEA and Cyfra21-1, the performance of MUC1 and EpCAM mRNA in malignant PE diagnosis was better. MUC1 and EpCAM mRNA in combination with cytology is a highly sensitive and specific diagnostic tool for detecting malignancy in PE. [ABSTRACT FROM AUTHOR]

Background:We have recently identified miR-125b upregulation in glioblastoma (GMB). The aim of this study is to determine the correlation between miR-125b expression and malignant grades of glioma and the genes targeted by miR-125b.Methods:Real-time PCR was employed to measure the expression level of miR-125b. Cell viability was evaluated by cell growth and colony formation in soft-agar assays. Cell apoptosis was determined by Hoechst 33342 staining and AnnexinV-FITC assay. The Luciferase assay was used to confirm the actual binding sites of p38MAPK mRNA. Western blot was used to detect the gene expression level.Results:The expression level of miR-125b is positively correlated with the malignant grade of glioma. Ectopic expression of miR-125b promotes the proliferation of GMB cells. Knockdown of endogenous miR-125b inhibits cell proliferation and promotes cell apoptosis. Further studies reveal that p53 is regulated by miR-125b. However, downregulation of the endogenous miR-125b also results in p53-independent apoptotic pathway leading to apoptosis in p53 mutated U251 cells and p53 knockdown U87 cells. Moreover, p38MAPK is also regulated by miR-125b and downregulation of miR-125b activates the p38MAPK-induced mitochondria apoptotic pathway.Conclusion:High-level expression of miR-125b is associated with poor outcomes of GMB. MiR-125b may have an oncogenic role in GMB cells by promoting cell proliferation and inhibiting apoptosis. [ABSTRACT FROM AUTHOR]

Aims Ansamycins are a family of macrolactams that are synthesized by type I polyketide synthase ( PKS) using 3-amino-5-hydroxybenzoic acid ( AHBA) as the starter unit. Most members of the family have strong antimicrobial, antifungal, anticancer and/or antiviral activities. We aimed to discover new ansamycins and/or other AHBA-containing natural products from actinobacteria. Methods and Results Through PCR screening of AHBA synthase gene, we identified 26 AHBA synthase gene-positive strains from 206 plant-associated actinomycetes (five positives) and 688 marine-derived actinomycetes (21 positives), representing a positive ratio of 2·4-3·1%. Twenty-five ansamycins, including eight new compounds, were isolated from six AHBA synthase gene-positive strains through TLC-guided fractionations followed by repeated column chromatography. To gain information about those potential ansamycin gene clusters whose products were unknown, seven strains with phylogenetically divergent AHBA synthase genes were subjected to fosmid library construction. Of the seven gene clusters we obtained, three show characteristics for typical ansamycin gene clusters, and other four, from Micromonospora spp., appear to lack the amide synthase gene, which is unusual for ansamycin biosynthesis. The gene composition of these four gene clusters suggests that they are involved in the biosynthesis of a new family of hybrid PK- NRP compounds containing AHBA substructure. Conclusions PCR screening of AHBA synthase is an efficient approach to discover novel ansamycins and other AHBA-containing natural products. Significance and Impact of the Study This work demonstrates that the AHBA-based screening method is a useful approach for discovering novel ansamycins and other AHBA-containing natural products from new microbial resources. [ABSTRACT FROM AUTHOR]