Myeloproliferative Disorders
Conditions which cause proliferation of hemopoietically active tissue or of tissue which has embryonic hemopoietic potential. They all involve dysregulation of multipotent MYELOID PROGENITOR CELLS, most often caused by a mutation in the JAK2 PROTEIN TYROSINE KINASE.
Myelodysplastic Syndromes
Clonal hematopoietic stem cell disorders characterized by dysplasia in one or more hematopoietic cell lineages. They predominantly affect patients over 60, are considered preleukemic conditions, and have high probability of transformation into ACUTE MYELOID LEUKEMIA.
Janus Kinase 2
A Janus kinase subtype that is involved in signaling from GROWTH HORMONE RECEPTORS; PROLACTIN RECEPTORS; and a variety of CYTOKINE RECEPTORS such as ERYTHROPOIETIN RECEPTORS and INTERLEUKIN RECEPTORS. Dysregulation of Janus kinase 2 due to GENETIC TRANSLOCATIONS have been associated with a variety of MYELOPROLIFERATIVE DISORDERS.
Primary Myelofibrosis
A de novo myeloproliferation arising from an abnormal stem cell. It is characterized by the replacement of bone marrow by fibrous tissue, a process that is mediated by CYTOKINES arising from the abnormal clone.
Myelodysplastic-Myeloproliferative Diseases
Clonal myeloid disorders that possess both dysplastic and proliferative features but are not properly classified as either MYELODYSPLASTIC SYNDROMES or MYELOPROLIFERATIVE DISORDERS.
Polycythemia Vera
A myeloproliferative disorder of unknown etiology, characterized by abnormal proliferation of all hematopoietic bone marrow elements and an absolute increase in red cell mass and total blood volume, associated frequently with splenomegaly, leukocytosis, and thrombocythemia. Hematopoiesis is also reactive in extramedullary sites (liver and spleen). In time myelofibrosis occurs.
Thrombocythemia, Essential
A clinical syndrome characterized by repeated spontaneous hemorrhages and a remarkable increase in the number of circulating platelets.
Anemia, Refractory
Leukemia, Myelomonocytic, Chronic
A myelodysplastic-myeloproliferative disease characterized by monocytosis, increased monocytes in the bone marrow, variable degrees of dysplasia, but an absence of immature granulocytes in the blood.
Receptors, Thrombopoietin
Cell surface receptors that are specific for THROMBOPOIETIN. They signal through interaction with JANUS KINASES such as JANUS KINASE 2.
Bone Marrow Neoplasms
Neoplasms located in the bone marrow. They are differentiated from neoplasms composed of bone marrow cells, such as MULTIPLE MYELOMA. Most bone marrow neoplasms are metastatic.
Anemia, Refractory, with Excess of Blasts
Leukemia, Myeloid, Acute
Clonal expansion of myeloid blasts in bone marrow, blood, and other tissue. Myeloid leukemias develop from changes in cells that normally produce NEUTROPHILS; BASOPHILS; EOSINOPHILS; and MONOCYTES.
Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative
A myelodysplastic/myeloproliferative disorder characterized by myelodysplasia associated with bone marrow and peripheral blood patterns similar to CHRONIC MYELOID LEUKEMIA, but cytogenetically lacking a PHILADELPHIA CHROMOSOME or bcr/abl fusion gene (GENES, ABL).
Leukemia, Myeloid
Form of leukemia characterized by an uncontrolled proliferation of the myeloid lineage and their precursors (MYELOID PROGENITOR CELLS) in the bone marrow and other sites.
Bone Marrow
The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells.
Leukemia, Myelomonocytic, Juvenile
A leukemia affecting young children characterized by SPLENOMEGALY, enlarged lymph nodes, rashes, and hemorrhages. Traditionally classed as a myeloproliferative disease, it is now considered a mixed myeloproliferative-mylelodysplastic disorder.
Anemia, Sideroblastic
Mutation
Chromosomes, Human, Pair 5
Proto-Oncogene Proteins c-cbl
Hematologic Neoplasms
Neoplasms located in the blood and blood-forming tissue (the bone marrow and lymphatic tissue). The commonest forms are the various types of LEUKEMIA, of LYMPHOMA, and of the progressive, life-threatening forms of the MYELODYSPLASTIC SYNDROMES.
Azacitidine
Leukemia, Myelogenous, Chronic, BCR-ABL Positive
Clonal hematopoetic disorder caused by an acquired genetic defect in PLURIPOTENT STEM CELLS. It starts in MYELOID CELLS of the bone marrow, invades the blood and then other organs. The condition progresses from a stable, more indolent, chronic phase (LEUKEMIA, MYELOID, CHRONIC PHASE) lasting up to 7 years, to an advanced phase composed of an accelerated phase (LEUKEMIA, MYELOID, ACCELERATED PHASE) and BLAST CRISIS.
Leukemia
A progressive, malignant disease of the blood-forming organs, characterized by distorted proliferation and development of leukocytes and their precursors in the blood and bone marrow. Leukemias were originally termed acute or chronic based on life expectancy but now are classified according to cellular maturity. Acute leukemias consist of predominately immature cells; chronic leukemias are composed of more mature cells. (From The Merck Manual, 2006)
Philadelphia Chromosome
An aberrant form of human CHROMOSOME 22 characterized by translocation of the distal end of chromosome 9 from 9q34, to the long arm of chromosome 22 at 22q11. It is present in the bone marrow cells of 80 to 90 per cent of patients with chronic myelocytic leukemia (LEUKEMIA, MYELOGENOUS, CHRONIC, BCR-ABL POSITIVE).
Blast Crisis
An advanced phase of chronic myelogenous leukemia, characterized by a rapid increase in the proportion of immature white blood cells (blasts) in the blood and bone marrow to greater than 30%.
Prognosis
Chromosome Aberrations
Abnormal number or structure of chromosomes. Chromosome aberrations may result in CHROMOSOME DISORDERS.
Bone Marrow Diseases
Bone marrow diseases, also known as hematologic or blood disorders, refer to conditions that affect the production and function of blood cells within the bone marrow, such as leukemia, lymphoma, myeloma, and aplastic anemia, potentially leading to complications like anemia, neutropenia, thrombocytopenia, and increased susceptibility to infections or bleeding.
Hematology
Monosomy
Preleukemia
Conditions in which the abnormalities in the peripheral blood or bone marrow represent the early manifestations of acute leukemia, but in which the changes are not of sufficient magnitude or specificity to permit a diagnosis of acute leukemia by the usual clinical criteria.
Myeloid Progenitor Cells
Stem cells derived from HEMATOPOIETIC STEM CELLS. Derived from these myeloid progenitor cells are the MEGAKARYOCYTES; ERYTHROID CELLS; MYELOID CELLS; and some DENDRITIC CELLS.
Janus Kinases
A family of intracellular tyrosine kinases that participate in the signaling cascade of cytokines by associating with specific CYTOKINE RECEPTORS. They act upon STAT TRANSCRIPTION FACTORS in signaling pathway referred to as the JAK/STAT pathway. The name Janus kinase refers to the fact the proteins have two phosphate-transferring domains.
Thalidomide
A piperidinyl isoindole originally introduced as a non-barbiturate hypnotic, but withdrawn from the market due to teratogenic effects. It has been reintroduced and used for a number of immunological and inflammatory disorders. Thalidomide displays immunosuppressive and anti-angiogenic activity. It inhibits release of TUMOR NECROSIS FACTOR-ALPHA from monocytes, and modulates other cytokine action.
Treatment Outcome
Megakaryocyte Progenitor Cells
Bone Marrow Cells
Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.
STAT5 Transcription Factor
A signal transducer and activator of transcription that mediates cellular responses to a variety of CYTOKINES. Stat5 activation is associated with transcription of CELL CYCLE regulators such as CYCLIN KINASE INHIBITOR P21 and anti-apoptotic genes such as BCL-2 GENES. Stat5 is constitutively activated in many patients with acute MYELOID LEUKEMIA.
Megakaryocytes
Very large BONE MARROW CELLS which release mature BLOOD PLATELETS.
Chromosomes, Human, Pair 7
Megakaryocyte-Erythroid Progenitor Cells
Cell Transformation, Neoplastic
Disease Progression
The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.
Pancytopenia
Anemia, Aplastic
A form of anemia in which the bone marrow fails to produce adequate numbers of peripheral blood elements.
Mutation, Missense
A mutation in which a codon is mutated to one directing the incorporation of a different amino acid. This substitution may result in an inactive or unstable product. (From A Dictionary of Genetics, King & Stansfield, 5th ed)
Clonal Evolution
Cytogenetic Analysis
Examination of CHROMOSOMES to diagnose, classify, screen for, or manage genetic diseases and abnormalities. Following preparation of the sample, KARYOTYPING is performed and/or the specific chromosomes are analyzed.
Neoplasms, Second Primary
Abnormal growths of tissue that follow a previous neoplasm but are not metastases of the latter. The second neoplasm may have the same or different histological type and can occur in the same or different organs as the previous neoplasm but in all cases arises from an independent oncogenic event. The development of the second neoplasm may or may not be related to the treatment for the previous neoplasm since genetic risk or predisposing factors may actually be the cause.
Myelopoiesis
Formation of MYELOID CELLS from the pluripotent HEMATOPOIETIC STEM CELLS in the BONE MARROW via MYELOID STEM CELLS. Myelopoiesis generally refers to the production of leukocytes in blood, such as MONOCYTES and GRANULOCYTES. This process also produces precursor cells for MACROPHAGE and DENDRITIC CELLS found in the lymphoid tissue.
Fusion Proteins, bcr-abl
Translation products of a fusion gene derived from CHROMOSOMAL TRANSLOCATION of C-ABL GENES to the genetic locus of the breakpoint cluster region gene on chromosome 22. Several different variants of the bcr-abl fusion proteins occur depending upon the precise location of the chromosomal breakpoint. These variants can be associated with distinct subtypes of leukemias such as PRECURSOR CELL LYMPHOBLASTIC LEUKEMIA-LYMPHOMA; LEUKEMIA, MYELOGENOUS, CHRONIC, BCR-ABL POSITIVE; and NEUTROPHILIC LEUKEMIA, CHRONIC.
Amino Acid Substitution
The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.
Point Mutation
A mutation caused by the substitution of one nucleotide for another. This results in the DNA molecule having a change in a single base pair.
Gene Knock-In Techniques
Down Syndrome
A chromosome disorder associated either with an extra chromosome 21 or an effective trisomy for chromosome 21. Clinical manifestations include hypotonia, short stature, brachycephaly, upslanting palpebral fissures, epicanthus, Brushfield spots on the iris, protruding tongue, small ears, short, broad hands, fifth finger clinodactyly, Simian crease, and moderate to severe INTELLECTUAL DISABILITY. Cardiac and gastrointestinal malformations, a marked increase in the incidence of LEUKEMIA, and the early onset of ALZHEIMER DISEASE are also associated with this condition. Pathologic features include the development of NEUROFIBRILLARY TANGLES in neurons and the deposition of AMYLOID BETA-PROTEIN, similar to the pathology of ALZHEIMER DISEASE. (Menkes, Textbook of Child Neurology, 5th ed, p213)
Granulocyte Precursor Cells
Hematopoietic Stem Cell Transplantation
Transfer of HEMATOPOIETIC STEM CELLS from BONE MARROW or BLOOD between individuals within the same species (TRANSPLANTATION, HOMOLOGOUS) or transfer within the same individual (TRANSPLANTATION, AUTOLOGOUS). Hematopoietic stem cell transplantation has been used as an alternative to BONE MARROW TRANSPLANTATION in the treatment of a variety of neoplasms.