Cell transformation and gene expression induced by metal working fluid in BALB/c-3T3 cells.
Keshava-N; Lin-F; Huffman-D; Chen-ZY; Ong-T
Environ Mol Mutagen 2001 Mar; 37(Suppl 32):42
Metal working fluids (MWF) are commonly used in the lubricant production and compounding industries and in the manufacturing industries that perform machining, grinding, forming or treating operations. It is estimated that 1.2 million workers are potentially exposed to MWF through inhalation or skin exposures. To study the transforming potential of MWF, BALB/c-3T3 cells were exposed to MWF at varying concentrations for 24 hours. The media was washed and the cells were further allowed to grow for four weeks. The cells were stained with 10% Giemsa and Type 3 foci were analyzed. Ten focal colonies were isolated from Type 3 foci and transformed cell lines were derived. DNA and RNA were isolated from each transformed cell line. Gene amplification and gene expression of several proto-oncogenes (K-ras, c-jun, c-fos, c-myc, c-sis and erb-B2) and tumor suppressor genes (p53 and p16) were studied using differential PCR. Random Amplified Polymorphic DNA (RAPD) analysis was carried out to study genomic changes using 10 different random primers. Results show that MWF caused a significant increase in transformation frequency in a dose-dependent manner. Also, the cytotoxicity data indicated a dose-dependent decrease in the cell number after MWF treatment. None of the genes studied were amplified in these transformed cells. However, increased expression of c-jun and c-fos was observed. No significant genomic changes were observed by RAPD analysis. These results indicate that MWF is capable of inducing morphological transformation in BALB/c-3T3 cells and that alteration in c-jun and c-fos expression in associated with MWF-induced transformation.
Cell-transformation; Genes; Skin-exposure; Oncogenesis; Tumors; Cytotoxicity; Metalworking-fluids; Workers; Occupational-exposure
Abstract; Conference/Symposia Proceedings
Environmental and Molecular Mutagenesis