ARSENIC-RELATED BOWENS-DISEASE AND PARAQUAT-RELATED SKIN CANCEROUS LESIONS SHOW NO DETECTABLE RAS AND P53 GENE ALTERATIONS

We have investigated point mutations of condons 12, 13, and 61 in H-, K-, and N-ras oncogenes as well as p53 tumour suppressor gene exon 5 t hrough exon 9 by PCR-SSCP analysis in 26 skin biopsy tissues from 16 a rsenic-related Bowen's disease patients and 6 skin samples from 4 para quat manufacturing workers. No mutation was found. These results are d ifferent from findings with UV associated skin cancers. Interestingly, a silent change at condon 27 of H-ras in one allele was detected in al l 4 paraquat manufacturing workers and in 2 of 16 arsenic-related Bowe n's disease patients. It is likely that the molecular mechanisms invol ved in arsenic and paraquat induced skin cancers differ from sunlight- related skin maligancies.