The Study On The Malignant Transformation Of Immortalized Human Bronchial Epithelial Cells BEAS-2B Induced By Tin Mine Dust In Yunnan Province

Objectives: To study the malignant transformation effects of Yunnan tin mine dust on immortalized human bronchial epithelial cells (BEAS-2B) in vitro, further investigate the genotoxicity of Yunnan tin mine dust, the expression of P53 pathway proteins in the malignant transformation cells of BEAS-2B induced by tin mine dust and using cDNA microarray to analyze the differences in the gene expression profiles between the early transformation cells and normal BEAS-2B cells for revealing the carcinogenesis and mechanism of lung cancer in Yunnan tin miners.Methods: (1) BEAS-2B cells were reacted with the tin mine dust at the concentration of 200μg/ml and 50μg/ml for 72 hours on every other generation which were stopped in 9th generation, including a negative control group. The characteristics of the cellular biology and the malignant transformation phenotype of cells were identified through observing the serum resistance, anchorage independent growth, etc. (2) By the single-cell gel electrophoresis assay (the comet assay) and the chromosome aberration analyses we observed the genotoxicity of BEAS-2B cells reacted by tin mine dust and the chromosome changes of BEAS-2B with cell transformation experiment. (3) BEAS-2B cells, the 25th generation cells reacted by mine dust (BEAS-MD-25) and the selected in soft agar medium colon cells (BEAS-MD-C) were examined for P53, MDM2, P21 and P16 proteins expression by immunofluorescence cytochemistry staining techniques. (4) RNAs from BEAS-MD-25 and BEAS-2B cells were extracted for reversed transcription cDNA probes. The mixed probes were hybridized with Affymetrix genechip human genome U133 plus 2.0. Different gene expression profiles were obtained by GCOS software.Results: (1) Each group cells in 20th generation didn't show the serum resistance. To high concentration group cells in 25th generation, the multiplication time, the serum...