Chronic myelocytic leukemia--Part I: History, clinical presentation, and molecular biology.
ABSTRACT DATA SYNTHESIS: Chronic myelocytic leukemia (CML) was initially described in 1845 and is considered one of the first leukemias to be discovered. Diagnosis of CML was dramatically improved with the discovery of the Philadelphia chromosome by Nowell and Hungerford in 1960. However, the rudiments of our understanding of the molecular cause of CML began in 1973 when Janet Rowley discovered that the Philadelphia chromosome is a reciprocal translocation between chromosomes 9 and 22. The leukemogenic mechanisms of CML were hypothesized 20 years later when it was discovered that the t(9;22) translocation produced a fusion gene involving the BCR gene from chromosome 22 and the ABL protooncogene from chromosome 9 [corrected] Multiple breakpoints in BCR produce fusion genes that are translated into chimeric protein products of different lengths that are associated with different leukemic subtypes. CONCLUSION: Although CML has a rich history of interest to hematologists, it also represents a leukemogenic paradigm to the molecular biologist. Nearly all malignancies result from a series of mutagenic events, which culminate in full malignant transformation. However, it appears that CML results from a single mutagenic event involving the t(9;22) translocation leading to the development of the BCR/ABL fusion gene and the corresponding fusion protein. The successful transcription and translation of the BCR/ABL fusion protein led researchers to carefully study its involvement in leukemogenesis. The BCR/ABL fusion protein exhibits increased and constitutive tyrosine kinase activity that differs depending on which BCR breakpoint is expressed, resulting in varying clinical presentations.
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ABSTRACT: The chronic leukaemias include two distinct chronic neoplastic disease states, namely chronic myelogenous leukaemia (CML) and chronic lymphocytic leukaemia (CLL). The aim of this study was to assess the utility of leucocyte count, neutrophil percentage and absolute lymphocyte count from differential complete blood count analyses as indicators of the possible presence of CML and CLL. Blood counts from 102 patients with histopathologically confirmed CML and CLL were compared with counts for 858 cancer-free control subjects. Optimal cut-off values were identified by selecting values with the highest sensitivity-specificity combination for each blood count parameter for the two diseases. The results indicated that any individual with mature-appearing lymphocytes at a level > 6.65 x 10(9)/l in the peripheral blood should be examined further for CLL, and that any individual with a leucocyte count > 18.0 x 10(9)/l or a neutrophil proportion > 72.6% should be investigated for CML.The Journal of international medical research 11/2006; 34(6):640-7. DOI:10.1177/147323000603400609 · 1.10 Impact Factor
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ABSTRACT: Chromosomal rearrangements are frequently in humans and can be disease-associated or phenotypically neutral. Recent technological advances have led to the discovery of copy-number changes previously undetected by cytogenetic techniques. To understand the genetic consequences of such genomic changes, these mutations need to be modeled in experimentally tractable systems. The mouse is an excellent organism for this analysis because of its biological and genetic similarity to humans, and the ease with which its genome can be manipulated. Through chromosome engineering, defined rearrangements can be introduced into the mouse genome. The resulting mouse models are leading to a better understanding of the molecular and cellular basis of dosage alterations in human disease phenotypes, in turn opening new diagnostic and therapeutic opportunities.Annual Review of Genomics and Human Genetics 02/2006; 7:247-76. DOI:10.1146/annurev.genom.7.080505.115741 · 9.13 Impact Factor
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ABSTRACT: Protein tyrosine kinases are key biochemical effectors of the signaling pathways that drive both normal and aberrant cell behavior. The ability to visualize the activity of tyrosine kinases in both a continuous and sensitive fashion will have a dramatic impact on the identification and characterization of inhibitors, the elucidation of the biochemical role of protein tyrosine kinases in various biological processes, and the imaging of kinase action in cells, tissues, and whole organisms. Several chemical strategies have recently been described that translate the formation of a phosphorylated tyrosine residue into a fluorescent readout. The challenges associated with the design of protein tyrosine kinase sensors, as well as the scope and limitations of the currently available sensors, are described.ChemBioChem 05/2007; 8(4):373-8. DOI:10.1002/cbic.200600473 · 3.06 Impact Factor