[K-ras gene mutations of asbestos and welding-fumes related human lung cancer].
To investigate the K-ras gene mutations in asbestos and welding-fumes related human lung cancer (hLC), comparing with the mutational spectrum of K-ras gene in non-occupational hLC, 8 cases of non-occupational hLC, 9 cases of asbestos-related hLC and 4 cases of welding-fumes related hLC were collected. The techniques of genomic DNA extraction, nested-polymerase chain reaction (PCR), polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP), polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and DNA direct sequencing were employed.


RESULTS
showed the mutation frequencies of K-ras gene were 25% in non-occupational hLC and welding-fumes related hLC, whereas 44.4% in asbestos-related hLC. Mutations mainly occurred in codons 12 and 15. A mutation of codon 13 was detected in welding-fumes related hLC. The type of base substitution was principally G-->T transversion in non-occupational hLC, whereas mainly G-->A transition in asbestos and welding-fumes related hLC. THE RESULTS suggested there were obvious differences of K-ras gene mutations among non-occupational hLC, asbestos and silica related hLC. Therefore, different mechanisms of carcinogenesis were implicated among them. However, no speific spectrum of K-ras gene mutation can be derived from welding-fumes related hLC because of the limitation of samples.
Institute of Occupational Medicine, Chinese Academy of Preventive Medicine, Beijing 100050, China.
B
B
Huang
B
B
Liu
M
M
Xu
B
B
You
D001194:Asbestos / Q000009:adverse effects*; D004391:Dust; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D008175:Lung Neoplasms / Q000209:etiology / Q000235:genetics*; D016273:Occupational Exposure; D017354:Point Mutation; D014896:Welding
D004391:Dust; D001194:Asbestos