Investigation of the role of the ras protooncogene point mutation in human uveal melanomas.
OBJECTIVE
Genetic alterations have been observed in a wide variety of neoplastic processes, including Burkitt's lymphoma, chronic myelogenous leukemia, promyelocytic leukemia, and solid tumors of the colon, skin, and breast. The polymerase chain reaction (PCR), dot blotting, and direct double-stranded DNA sequencing were used to assess ras gene activation in human uveal melanomas for three candidate genes: c-Ha-ras1, c-Ki-ras2, and N-ras at codons 12, 13, and 61.


METHODS
Samples of 49 human uveal melanomas were obtained. Amplifiable high molecular weight DNA was obtained from 39 of these. PCR amplification of regions centering on three candidate ras genes was performed. PCR-amplified DNA was evaluated by dot blot and double-stranded DNA sequencing utilizing standard methods.


RESULTS
No point mutations were identified in screening the c-Ha-ras gene nor were any genetic alterations found in the c-Ki-ras2 gene at codons 12 and 13. Only wild-type sequences were found at codon 61. No ras mutations were detected in any uveal melanomas studied.


CONCLUSIONS
This study provides no evidence to support an association between ras protooncogene mutations and human uveal melanomas at codons 12, 13, or 61.
Department of Pathology, University of Massachusetts Medical Center, Worcester.
C N
CN
Soparker
J M
JM
O'Brien
D M
DM
Albert
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D003062:Codon; D004273:DNA, Neoplasm; D005260:Female; D011905:Genes, ras; D006801:Humans; D015151:Immunoblotting; D008297:Male; D008545:Melanoma / Q000235:genetics*; D008875:Middle Aged; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics; D012878:Skin Neoplasms / Q000235:genetics*; D014604:Uveal Neoplasms / Q000235:genetics*
D003062:Codon; D004273:DNA, Neoplasm; D015345:Oligonucleotide Probes; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)