Proto-Oncogene Activation and Genomic Instability of Cadmium-Induced Cell Transformation in BALB/C-3T3 Cells

Details

• Personal Author:
  Ong T ; Song B ; Spruill MD ; Whong, Wen-Zong
• Description:
  Cadmium (Cd) is an essential material used in the battery, metal-coating, and alloy industries. In addition to these industrial uses, it is also a component of cigarette smoke. Therefore, exposure to cadmium is widespread and presents a considerable health concern. Cadmium is known to be a carcinogen; however, the possible mechanism of carcinogenesis with regards to the activation and inactivation of cancer-related genes has not yet been fully elucidated. In this study, amplification, expression, and point mutation of cancer-related genes associated with Cd-induced cell transformation in BALB/c-3T3 cells were studied. Six proto-oncogenes (K-ras, c-myc, c-fos, c-jun, c-sis, and erbB), as well as the p53 tumor suppressor, were investigated for gene amplification using differential polymerase chain reaction (PCR), while the expression of the proteins produced by these genes was evaluated by Western blot analysis. Point mutations in K-ras and p53 were studied by PCR restriction fragment length polymorphism analysis and DNA sequencing. There were no point mutations observed in codons 12, 13, and 61 of K-ras or in exons 4-10 of p53 and no observed differences in the levels of any of the proteins studied. Among 10 Cd-induced transformed cell lines, significant gene amplification was found for c-myc and c-jun in 50% and 80% of the cell lines, respectively. Chromosome painting was performed to confirm that this amplification was not simply due to additional copies of the chromosomes carrying these oncogenes. In addition, reverse-transcription PCR (RT-PCR) was performed to confirm increased expression of c-myc and c-jun. These results suggest that cell transformation induced by Cd may be attributed, at least in part, to gene amplification of c-myc and c-jun and that some of the Cd-transformed cells may possess neoplastic potential resulting from genomic instability. [Description provided by NIOSH]
• Subjects:
  Carcinogens Genetics Hazardous Substances Metals, Heavy Neoplasms Occupational Health Safety Smokers Tobacco Products
• Keywords:
  Cadmium Compounds Cancer Carcinogenesis Cell Transformation Cigarette Smoking Genes Health Hazards Heavy Metals Oncogenesis Proteins
• ISSN:
  0098-4108
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  65
• Issue:
  24
• NIOSHTIC Number:
  nn:20023533
• Citation:
  J Toxicol Environ Health A 2002 Dec; 65(24):2131-2144
• CAS Registry Number:
  Cadmium (CAS RN 7440-43-9)
• Federal Fiscal Year:
  2003
• NORA Priority Area:
  Research Tools and Approaches: Cancer Research Methods
• Peer Reviewed:
  True
• Source Full Name:
  Journal of Toxicology and Environmental Health, Part A: Current Issues
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:4781a232a71c573e9029145a0a900f07fdf3017f24a5c4bec87d2bf50407c2ed61370a524325899cf50f76a427e52d70f694eda8f27f741b1ff2cc8976f37b6e
• Download URL:
  https://stacks.cdc.gov/view/cdc/195904/cdc_195904_DS1.pdf
• File Type:
  [PDF - 522.06 KB ]