A mutation within NRAS codon 12 could thus be demonstrated in a patient with idiopathic myelofibrosis and in another with chronic myelomonocytic leukemia.
Although mutations in the ras gene family may occur frequently in leukaemias, these are the first examples of Ha-ras mutations in CGL (blast crisis) and CMML.
Karyotypes of different cellular populations made after separation of bone marrow cells on a gradient of Percoll were evaluated in seven patients affected by chronic myelomonocytic leukemia diagnosed according to FAB criteria.
Thus, RAS mutations appear to be associated with CMML and not Ph1-/BCR- chronic phase CML, there is a high propensity for the K-ras or N-ras mutations to involve an G----A substitution in the 12th or 13th codons, and RAS mutations in CMML may relate to prognosis and require further studies.
Five patients had myelodysplastic syndrome (MDS) diagnosed according to the FAB nomenclature as chronic myelomonocytic leukemia (CMML) in two cases, refractory anemia with excess of blasts in transformation (RAEBt) in two cases, and refractory anemia with excess of blasts (RAEB) in one case.
Although FRA16B was detected only in PBLs from two healthy subjects who had been previously treated for non-Hodgkin's lymphoma (NHL), both cell types displayed FRA16B in a patient with chronic myelomonocytic leukemia (CMMoL).
We therefore analyzed samples obtained from 57 patients with a variety of hematologic malignancies (21, acute myelogenous leukemia; 14, acute lymphoblastic leukemia; 12, Philadelphia chromosome-positive chronic myelogenous leukemia [blast phase] or acute leukemia; 5, chronic lymphocytic leukemia; and 5, chronic myelomonocytic leukemia) for expression of interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) transcripts on Northern blots.
We therefore analyzed samples obtained from 57 patients with a variety of hematologic malignancies (21, acute myelogenous leukemia; 14, acute lymphoblastic leukemia; 12, Philadelphia chromosome-positive chronic myelogenous leukemia [blast phase] or acute leukemia; 5, chronic lymphocytic leukemia; and 5, chronic myelomonocytic leukemia) for expression of interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) transcripts on Northern blots.
Since mutations in the N-ras gene have been found at high frequencies in CMMoL, but only rarely in CML, we analyzed mutations activating the N-ras gene in 20 patients with JCML.