Role of chromosomal abnormalities in chronic lymphocytic leukemia.
Chromosomal aberrations occur in both B-CLL and T-CLL. The polyclonal B-cell mitogens, in particular Epstein-Barr virus and lipopolysaccharide from E. coli, have been used successfully to reveal chromosomal abnormalities in 40-60% of patients with B-CLL, while T-cell mitogens have shown chromosomal aberrations in T-CLL. The most common clonal chromosomal aberration in B-CLL is an extra chromosome 12, alone or together with other abnormalities. Other common aberrations are 14q+, structural aberrations on 6, 11, 12 and 13. Proto-oncogenes are frequently located close to breakpoints. The proto-oncogene c-K-ras is located on chromosome 12 and an abnormal transcript has recently been implicated in a subset of B-CLL-patients. An extra chromosome 12 as well as multiple chromosomal abnormalities in B-CLL appear to predict a less favourable prognosis. T-CLL is in most patients characterized by an inv(14), an extra 8q and structural abnormalities in chromosome 7. The genes for the specific T-cell receptor as well as the immunoglobulin heavy chain are located on these chromosomes. Chromosomal aberrations appear to have pathogenetic importance in both B-CLL and T-CLL.
Gahrton
G
G
Department of Medicine, Huddinge Hospital, Sweden.
Juliusson
G
G
Robèrt
K H
KH
Friberg
K
K
D002869:Chromosome Aberrations; D006801:Humans; D007621:Karyotyping; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics*; D000090063:Proto-Oncogene Mas