High frequency of N-ras activation in acute myelogenous leukemia

Abstract

Using the NIH/3T3 cell transfection assay, activated cellular oncogenes have been detected in around 10% to 20% of human tumors. From a series of DNA preparations from tissues infiltrated with acute myelogenous leukemia (AML), 50% (3/6) caused transformation of NIH/3T3 cells. Thus AML appears to be the human tumor with the highest frequency of oncogenes detected by DNA transfection. In each case the oncogene involved was N-ras, a member of the ras gene family. Biologic and clinical parameters of AML patients with and without N-ras oncogenes in their tumors are discussed.

RAS gene mutations in childhood acute myeloid leukemia: A pediatric oncology group study

“…In summary, RAS gene mutations were identified in over a third of childhood cases of AML. Although estimates for the prevalence of such mutations in adult AML has varied (Needleman et al, 1986;Bos et al, 1987;Hirai et al, 1987;Toksoz et al, 1987;Farr et al, 1988;Senn et al, 1988;Yunis et al, 1988;Bartram et al, 1989), these mutations appear to be at least as common in pediatric cases as in adult cases. This suggests that the biologic differences between the leukemic cells in adult versus pediatric AML (Fialkow, 1984;Steuber et al, 1989) cannot be readily explained on the basis of RAS gene mutations.…”

Mutation analysis of the N‐ras proto‐oncogene in active and remission phase of human acute leukemias

“…Activated rus genes can transform NIH/3T3 cells and are thought to play a role in tumorigenesis, perhaps in tumor initiation (Zarbl et al, 1985;Brown et al, 1986). Previous studies of human leukemias have detected ras mutations predominantly in the N-ras and, occasionally, in the K-ras gene (Eva et Bos et al, , 1987Needleman et al, 1986).…”

Colorectoral excision specimens and prognosis

“…Lack of standardization in reporting of rectal carcinoma can only be a reflection of indifferent application of Dukes' classification that has served so well for the past 55 years. 3 Dukes' original protocol insisted on an unfixed specimen although he indicated that 1 per cent formalin would suffice until the rectum could be opened along the antimesenteric border and fastened to a cork board or frame. All too often laboratories receive a distorted specimen, partially fixed in 10 per cent formalin, rendering thin slicing, with mapping of lymph nodes difficult, if not impossible.…”