Autologous Bone Marrow Transplantation - Blog Science Connections

Clonal Detection of Remission by Restriction-
Fragment Length Polymorphism and Methylation
Analysis
Kerry Taylor, Sushant Hardikar, Craig Chinault, Ken McCredie,
and Gary Spitzer
With current intensive chemotherapy, morphologic remission in acute
nonlymphocytic leukemia (ANLL) can be attained in 65% to 70% of patients.
However, a patient who achieves complete remission has only a 20% to 25%
chance of remaining free of leukemia with the various chemotherapy
programs administered after remission ( 1 ). Possible reasons for the high risk
of recurrence include: 1 ) persistence of undetectable chemotherapy-resistant
leukemic cells; 2) de novo reinduction of leukemia in normal hematopoietic
stem cells; and 3) the persistence in remission of a preleukemic population
capable of differentiating into mature elements after frankly leukemic cells
have been killed by chemotherapy (2). This population may be susceptible to
development of overt leukemia with ensuing relapse. This latter hypothesis
envisages ANLL as arising from two or more genetic events: the first enables
emergence of a clone of hematopoietic preleukemic precursors that are
capable of normal differentiation but have a proliferative advantage over
normal precursors; the second, a successive event or events, allows overt
leukemia to supervene.
According to the somatic mutation theories of carcinogenesis, neo-
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