H‐ras and K‐ras mutations in soft tissue sarcoma: Comparative studies of sarcomas from Korean and American patients

J Yoo, RA Robinson - … Journal of the American Cancer Society, 1999 - Wiley Online Library
J Yoo, RA Robinson
Cancer: Interdisciplinary International Journal of the American …, 1999Wiley Online Library
BACKGROUND The authors' recent investigation of Korean patients with sarcoma has
suggested that ras gene activation may play a role in oncogenesis. The authors attempted to
extend the mutation analysis to sarcomas in American patients to determine whether there
were racial or geographic factors relevant to the initiation or progression of sarcoma.
METHODS H‐ras and K‐ras genes were examined in sarcomas obtained from patients in
the midwestern US using the polymerase chain reaction technique and direct automated …
BACKGROUND
The authors' recent investigation of Korean patients with sarcoma has suggested that ras gene activation may play a role in oncogenesis. The authors attempted to extend the mutation analysis to sarcomas in American patients to determine whether there were racial or geographic factors relevant to the initiation or progression of sarcoma.
METHODS
H‐ras and K‐ras genes were examined in sarcomas obtained from patients in the midwestern U. S. using the polymerase chain reaction technique and direct automated sequencing analysis. Tumors studied included 29 malignant fibrous histiocytomas, 7 liposarcomas, 5 rhabdomyosarcomas, and 9 leiomyosarcomas.
RESULTS
Of the 50 sarcomas evaluated, only 1 (2%) definable mutation was found; a GGC to AGC transition at codon 12 of H‐ras was found in a rhabdomyosarcoma. None of the patients had a K‐ras mutation. The rates of incidence of ras point mutations in these samples were much lower (H‐ras: 2%; 95% confidence interval [95% CI], 0‐11.5% and K‐ras: 0%) than described for both genes in Korean studies (H‐ras: 16%; 95% CI, 5.2‐26.8% and K‐ras: 44%; 95% CI, 29.5‐58.5%).
CONCLUSIONS
Although the reason for this discrepancy is not clear, there were no major differences found in histology or clinical stages. Based on this study of 50 sarcoma samples from American patients and the authors' previous study of 45 Korean tumor samples, the authors conclude that differing genetic and/or environmental mechanisms can affect sarcoma development or progression. Mutation of the H‐ras and K‐ras genes appears to be uncommon in sarcomas occurring in American patients, suggesting that the activation by point mutations of the H‐ras and K‐ras genes does not play a significant role in the pathogenesis or progression of sarcoma in these patients. Cancer 1999;86:58–63. © 1999 American Cancer Society.
Wiley Online Library