Problematic WHO reclassification of myelodysplastic syndromes. Members of the International MDS Study Group.
Explore the source record for details and available documents.
Acute Disease↗
Biomedical subjects
C Willman
Publications and source records attributed to C Willman.
Three-color versus four-color multiparameter cell cycle analyses of primary acute myeloid leukemia samples.
Checkpoint alterations that impact cell cycle and apoptosis responses to therapeutic treatments may produce drug resistance in acute myeloid leukemia (AML). To study these, we have developed flow cytometry assays of checkpoint function that also allow quantitation of key molecular regulators of apoptosis and cell cycle. We have used three-color (3C) assays, with FITC-labeled anti-BCL-2 and PE-labeled anti-proliferating cell nuclear antigen (PCNA) antibodies, and the DNA dye 7-aminoactinomycin, to characterize primary leukemia cells identified in DNA x side light scatter (SSC) histograms. We showed that 3C assays are accurate and reproducible in analyses of leukemia cell lines and of primary AML and normal bone marrow samples (Banker et al.: Blood 89: 243-255, 1997; Banker et al.: Leukemia Res 22: 221-239, 1998; Banker et al.: Clin Cancer Res 4: 3051-3062, 1998). To further confirm the validity of our SSC leukemia cell gating and to address whether immunophenotypic AML subsets might have different biologic properties, we have now designed four-color (4C) flow assays to characterize checkpoint status in leukemic blasts specifically identified by surface immunostaining. In modeling this assay strategy, PE/Cy5-labeled anti-CD34 antibody was used to detect blasts, with FITC-labeled anti-BCL-2, PE-labeled anti-PCNA antibodies, and Hoechst 33342 (H33342) DNA dye. Four-color CD34-gated data was concordant with 3C, SSC-gated data for leukemia cell lines and for most primary AML samples with high and intermediate blast counts. BCL-2 and PCNA immunopositivity and sub-G1 apoptosis determinations were different in the CD34-gated versus SSC-gated blasts in particular samples with smaller CD34(+) subsets, suggesting that leukemia samples can contain blast subsets with different biologic properties. On the other hand, PCNA-gated cell-cycle distributions in untreated cells and G1 versus S phase cell-cycle arrests after cytosine arabinoside treatments were completely concordant in 4C and 3C assays. We conclude that both 3C and 4C assays can be used to characterize protein expression and cell-cycle drug response patterns in leukemia blasts, but that 4C assays may additionally allow discrimination of these properties in immunophenotypic leukemia subsets.
Antibodies↗
Patient and tumor characteristics of colon cancers with microsatellite instability: a population-based study.
Molecular screening for microsatellite instability (MSI) in colon cancers has been proposed to identify individuals with hereditary nonpolyposis colorectal cancer. To date, most reports of MSI in colorectal cancer have been based on studies of clinical case series or high-risk families. We examined the proportion of incident colon cancers in the general population that exhibit MSI by patient and tumor characteristics. We interviewed 201 colon cancer cases ascertained by the New Mexico Tumor Registry in the metropolitan Albuquerque area for demographic information, lifestyle factors, medical history, and family cancer history. Paired normal and tumor tissue specimens were obtained for each case. Three microsatellite markers were used; instability was defined as observed alteration at two or more loci. Overall, 37 of 201 (18%) colon cancers exhibited instability. MSI was more common among cases >70 years (26%) and most common among cases >80 years (38%). MSI was significantly associated with tumors in the proximal colon and with later stage and poor differentiation among cases >70 years. MSI was not associated with a history of polyps. Family history of colorectal cancer was associated with MSI only among cases <50 years. When all factors were analyzed jointly in a regression model, proximal subsite and poor differentiation remained significantly associated with MSI. One patient, whose tumor exhibited MSI, fulfilled the Amsterdam Criteria for hereditary nonpolyposis colorectal cancer. Our study provides a population-based estimate of MSI in colon tumors and a representative estimate of the proportion of colorectal cancer patients in the general population who consent to be interviewed for family cancer history and to have biological samples analyzed.
Adult↗
Haploinsufficiency of CBFA2 causes familial thrombocytopenia with propensity to develop acute myelogenous leukaemia.
Familial platelet disorder with predisposition to acute myelogenous leukaemia (FPD/AML, MIM 601399) is an autosomal dominant disorder characterized by qualitative and quantitative platelet defects, and propensity to develop acute myelogenous leukaemia (AML). Informative recombination events in 6 FPD/AML pedigrees with evidence of linkage to markers on chromosome 21q identified an 880-kb interval containing the disease gene. Mutational analysis of regional candidate genes showed nonsense mutations or intragenic deletion of one allele of the haematopoietic transcription factor CBFA2 (formerly AML1) that co-segregated with the disease in four FPD/AML pedigrees. We identified heterozygous CBFA2 missense mutations that co-segregated with the disease in the remaining two FPD/AML pedigrees at phylogenetically conserved amino acids R166 and R201, respectively. Analysis of bone marrow or peripheral blood cells from affected FPD/AML individuals showed a decrement in megakaryocyte colony formation, demonstrating that CBFA2 dosage affects megakaryopoiesis. Our findings support a model for FPD/AML in which haploinsufficiency of CBFA2 causes an autosomal dominant congenital platelet defect and predisposes to the acquisition of additional mutations that cause leukaemia.
Amino Acid Sequence↗
Comparison of asynchronous versus synchronous arm crank ergometry.
STUDY DESIGN: A direct comparison of synchronous versus asynchronous arm crank ergometry has not been carried out previously. Therefore, a comparative research design was employed. OBJECTIVE: To assess the physiological responses of arm cranking when performed asynchronously (arms moving opposite to each other) versus synchronously (both arms moving in the same direction simultaneously). SETTING: A university hospital setting in Galveston, Texas, USA. METHODS: Seventeen individuals between the ages of 19 and 53 years were studied, 11 with paraplegia and six with no apparent disability. Two maximal arm crank graded exercise tests were performed with the subject seated in a wheelchair. Testing consisted of both arms (1) asynchronously (reciprocally) pushing and pulling the crank handles and (2) pushing and pulling the crank handles synchronously. Each test consisted of 2 min stages starting at 20 W and increasing 10 W per stage thereafter until exhaustion. Heart rate, oxygen consumption, and minute ventilation were measured and recorded during each stage. Blood lactate levels were monitored before and after each test. Statistical analysis was performed using the multivariate Hotelling's T2 followed by post hoc univariate tests. RESULTS: Greater power and longer test times (both groups, P<0.05) and higher post test blood lactates (nondisabled P<0.01, paraplegic P<0.05) were achieved with asynchronous cranking versus synchronous cranking. While submaximal responses were similar between the two modes of cranking, there was a tendency for all variables to be lower with asynchronous. All subjects preferred asynchronous rather than synchronous cranking. CONCLUSION: Despite few statistically significant differences, based on the subjective reports from all subjects, we believe there is a clinically significant difference between the two modes of cranking. The results suggest that the mode of cranking may have implications for arm crank testing, training, and functional locomotion in individuals with lower extremity impairments.
Adult↗
Chemotherapy compared with autologous or allogeneic bone marrow transplantation in the management of acute myeloid leukemia in first remission.
BACKGROUND: In young adults with acute myeloid leukemia, intensive chemotherapy during the initial remission improves the long-term outcome, but the role of bone marrow transplantation is uncertain. We compared high-dose cytarabine with autologous or allogeneic marrow transplantation during the first remission of acute myeloid leukemia. METHODS: Previously untreated adolescents and adults 16 to 55 years of age who had acute myeloid leukemia received standard induction chemotherapy. After complete remission had been achieved, idarubicin (two days) and cytarabine (five days) were administered. Patients with histocompatible siblings were offered allogeneic marrow transplantation, whereas the remaining patients were randomly assigned to receive a single course of high-dose cytarabine or transplantation of autologous marrow treated with perfosfamide (4-hydroperoxycyclophosphamide). Oral busulfan and intravenous cyclophosphamide were used as preparative regimens for both allogeneic and autologous marrow transplantation. The end points were survival from the time of complete remission and disease-free survival. RESULTS: In an intention-to-treat analysis, we found no significant differences in disease-free survival among patients receiving high-dose chemotherapy, those undergoing autologous bone marrow transplantation, and those undergoing allogeneic marrow transplantation. The median follow-up was four years. Survival after complete remission was somewhat better after chemotherapy than after autologous marrow transplantation (P=0.05). There was a marginal advantage in terms of overall survival with chemotherapy as compared with allogeneic marrow transplantation (P=0.04). CONCLUSIONS: A postinduction course of high-dose cytarabine can provide equivalent disease-free survival and somewhat better overall survival than autologous marrow transplantation in adults with acute myeloid leukemia.
Acute Disease↗
The t(8;21) translocation is not consistently associated with high Bcl-2 expression in de novo acute myeloid leukemias of adults.
Chromosomal translocations are commonly found in de novo acute myeloid leukemia (AML) cells, and the fusion proteins produced from these genetic abnormalities are assumed to contribute directly to leukemogenesis and/or progression. The AML1/ETO fusion protein, created by translocations between chromosomes 8 and 21 [t(8;21); G. Nucifora and J. D. Rowley, Leuk. Lymphoma, 14: 353-362, 1994; K. L. Rhoades et al., Proc. Natl. Acad. Sci. USA, 93: 11895-11900, 1996] can induce anti-apoptotic Bcl-2 expression in vitro and was proposed to thereby promote the survival of t(8;21)-bearing AML cells (L. Klampfer et al., Proc. Natl. Acad. Sci. USA, 93: 14059-14064, 1996). We confirm that cells of the t(8;21)-bearing Kasumi cell line do express high levels of Bcl-2 protein, as reported previously. However, we show that primary AML cells with (8;21) chromosomal translocations generally express low levels of Bcl-2 protein relative to normal bone marrow-derived myeloid cells and to AML samples with other simple karyotypic abnormalities. We note that p53 mutations are present in the myeloid cell lines expressing AML-ETO protein from chromosomal translocations (Kasumi and SKNO) or from transfected fusion genes (U937) but were undetected in our analyses of 28 primary t(8;21)-bearing AML cell samples from de novo AMLs. Because wild-type p53 can transcriptionally down-regulate bcl-2, we speculate that p53 mutations may contribute to the association of t(8;21) chromosomal abnormalities with higher Bcl-2 expression levels in leukemia cell lines. We also note that some t(8;21)-bearing samples from pediatric and older adult patients do express somewhat higher levels of Bcl-2 than t(8;21)-bearing samples from young adult patients. This suggests that Bcl-2 overexpression could occur in these AML cells by an as yet undefined, p53-independent mechanism and could contribute to the reported association of t(8;21) karyotypes with poor clinical outcomes in childhood AML patients and/or to typically poor clinical outcomes in elderly AML patients.
Acute Disease↗
All-trans-retinoic acid in acute promyelocytic leukemia.
BACKGROUND: All-trans-retinoic acid induces complete remission in acute promyelocytic leukemia. However, it is not clear whether induction therapy with all-trans-retinoic acid is superior to chemotherapy alone or whether maintenance treatment with all-trans-retinoic acid improves outcome. METHODS: Three hundred forty-six patients with previously untreated acute promyelocytic leukemia were randomly assigned to receive all-trans-retinoic acid or daunorubicin plus cytarabine as induction treatment. Patients who had a complete remission received consolidation therapy consisting of one cycle of treatment identical to the induction chemotherapy, then high-dose cytarabine plus daunorubicin. Patients still in complete remission after two cycles of consolidation therapy were then randomly assigned to maintenance treatment with all-trans-retinoic acid or to observation. RESULTS: Of the 174 patients treated with chemotherapy, 120 (69 percent) had a complete remission, as did 124 of the 172 (72 percent) given all-trans-retinoic acid (P=0.56). When both induction and maintenance treatments were taken into account, the estimated rates of disease-free survival at one, two, and three years were 77, 61, and 55 percent, respectively, for patients assigned to chemotherapy then all-trans-retinoic acid; 86, 75, and 75 percent for all-trans-retinoic acid then all-trans-retinoic acid; 75, 60, and 60 percent for all-trans-retinoic acid then observation; and 29, 18, and 18 percent for chemotherapy then observation. By intention-to-treat analysis, the rates of overall survival at one, two, and three years after entry into the study were 75, 57, and 50 percent, respectively, among patients assigned to chemotherapy, and 82, 72, and 67 percent among those assigned to all-trans-retinoic acid (P= 0.003). CONCLUSIONS: All-trans-retinoic acid as induction or maintenance treatment improves disease-free and overall survival as compared with chemotherapy alone and should be included in the treatment of acute promyelocytic leukemia.
Adolescent↗
An expression based clonality assay at the human androgen receptor locus (HUMARA) on chromosome X.
Explore the source record for details and available documents.
Base Sequence↗
Treatment outcome with chemotherapy in acute promyelocytic leukemia: the Southwest Oncology Group (SWOG) experience.
Because of interest in new approaches to treatment of patients with acute promyelocytic leukemia (APL), we analyzed APL treatment outcome in SWOG with chemotherapy from 1982-1991. To evaluate effects of change in nonspecific patient care factors over time we evaluated outcome in two temporal groups (1982-1986, 1986-1991), corresponding to two groups of treatment protocols encompassing all new de novo AML patients entered on acute myeloblastic leukemia (AML) protocols during those years. Surprisingly, APL patients in the 1982-1986 group (n = 45) had much better treatment outcome (complete remission (CR) rate 71%, median overall survival (OS) 106 months, median disease-free survival (DFS) > 105 months) than the later group (n = 96) (CR rate 47%, median OS 13 months, median DFS 28 months) (p = 0.0063, 0.0015, and 0.0001 respectively). All APL patients but two in the 1982-1986 time period were treated on SWOG protocol 8124, which included induction with total daunorubicin (DNR) 210 mg/m2 i.v./course, consolidation with two courses with identical dosage of DNR, and intensification at 4 months including another course of identical dosage DNR. We analyzed factors affecting treatment outcome for all patients with APL treated from 1982 to 1991. In multivariate analysis, higher DNR induction dose was significantly associated with CR rate, OS, and DFS (p < 0.001, < 0.0001, and < 0.0001, respectively). Cytosine arabinoside (ARA-C) dose and inclusion of other agents did not correlate significantly with outcome. Because these studies were not randomized for DNR dosage, other factors contributing to outcome cannot be completely excluded, although none were found. Most deaths occurred within 3 months of initiation of therapy on 8124; there were no relapses with higher DNR dosage after 3 years. This excellent outcome should be considered in evaluating newer modalities of therapy such as all-trans retinoic acid (ATRA) for APL. If the high CR induction rate and minimal early deaths with ATRA therapy can be combined successfully with this chemotherapy, most patients with APL may be curable.
Antineoplastic Agents↗
An AML1/ETO fusion transcript is consistently detected by RNA-based polymerase chain reaction in acute myelogenous leukemia containing the (8;21)(q22;q22) translocation.
The 8;21 translocation is one of the most common chromosomal translocations in acute myelogenous leukemia (AML), accounting for 40% of pediatric AML with French-American-British (FAB)-M2 morphology. The chromosomal breakpoints have recently been identified at the molecular level and shown to involve the AML1 gene on chromosome 21 and the ETO gene on chromosome 8. Translocation results in the consistent fusion of these genes on the der(8) chromosome, resulting in the production of a novel chimeric gene and message. Using oligonucleotide primers derived from the AML1 and ETO cDNAs, we were able to amplify a specific fusion transcript from 26 of 26 patients with t(8;21) by a reverse transcriptase polymerase chain reaction (PCR) approach. DNA fragments of identical size were generated from each case including two with complex translocations. Studies on the sensitivity and specificity of this approach show that PCR analysis can be used as a rapid, accurate, and sensitive means for detecting this chromosomal abnormality, and for following the patients' response to therapy.
Adolescent↗
Activation of the interleukin-3 gene by chromosome translocation in acute lymphocytic leukemia with eosinophilia.
The t(5;14)(q31;q32) translocation from B-lineage acute lymphocytic leukemia with eosinophilia has been cloned from two leukemia samples. In both cases, this translocation joined the IgH gene and the interleukin-3 (IL-3) gene. In one patient, excess IL-3 mRNA was produced by the leukemic cells. In the second patient, serum IL-3 levels were measured and shown to correlate with disease activity. There was no evidence of excess granulocyte/macrophage colony stimulating factor (GM-CSF) or IL-5 expression. Our data support the formulation that this subtype of leukemia may arise in part because of a chromosome translocation that activates the IL-3 gene, resulting in autocrine and paracrine growth effects.
Base Sequence↗
Cloning and characterization of the t(15;17) translocation breakpoint region in acute promyelocytic leukemia.
A reciprocal chromosomal translocation, t(15;17)(q22;q11.2-12), is characteristic of acute promyelocytic leukemia (APL) of French-American-British (FAB) subtype M3, and is not associated with any other human malignancy. The non-random pattern of the APL translocations suggests that specific genes on chromosomes 15 and 17 are somehow altered or deregulated as a consequence of the rearrangement. Translocation breakpoints in APL patients provide physical landmarks that suggest an approach to isolating the APL gene(s). Genetic and physical maps constructed for the APL breakpoint region on chromosome 17 have indicated that two fully-linked DNA markers, defining loci for THRA1 and D17S80, map to opposite sides of an APL breakpoint yet reside on a common 350-kb Clal fragment. Cosmid-walking experiments to clone this APL breakpoint have revealed a 38-kilobase deletion on chromosome 17. Studies in additional APL patients have shown that the breakpoint region on chromosome 17 spans at least 80 kilobases.
Chromosome Walking↗
Localization of preferential sites of rearrangement within the BCR gene in Philadelphia chromosome-positive acute lymphoblastic leukemia.
The Philadelphia chromosome associated with acute lymphoblastic leukemia (ALL) has been linked to a hybrid BCR/ABL protein product that differs from that found in chronic myelogenous leukemia. This implies that the molecular structures of the two chromosomal translocations also differ. Localization of translocation breakpoints in Philadelphia chromosome-positive ALL has been impeded due to the only partial characterization of the BCR locus. We have isolated the entire 130-kilobase BCR genomic locus from a human cosmid library. A series of five single-copy genomic probes from the 70-kilobase first intron of BCR were used to localize rearrangements in 8 of 10 Philadelphia chromosome-positive ALLs. We have demonstrated that these breakpoints are all located at the 3' end of the intron around an unusual restriction fragment length polymorphism caused by deletion of a 1-kilobase fragment containing Alu family reiterated sequences. This clustering is unexpected in light of previous theories of rearrangement in Philadelphia chromosome-positive chronic myelogenous leukemia that would have predicted a random dispersion of breakpoints in the first intron in Philadelphia chromosome-positive ALL. The proximity of the translocation breakpoints to this constitutive deletion may indicate shared mechanisms of rearrangement or that such polymorphisms mark areas of the genome prone to recombination.
Base Sequence↗
Nonleukemic granulocytic sarcoma of the heart: a report of a fatal case.
We report the clinical and pathological features of a cardiac fatality caused by granulocytic sarcoma in a young adult man with no evidence of leukemia involving bone marrow or peripheral blood. At autopsy, walls of the four cardiac chambers were massively infiltrated by tumor, resulting in a cardiac weight of almost three times normal. Routine cytochemical stains plus immunoperoxidase staining for OKM1 confirmed the diagnosis. Although subclinical cardiac infiltrates are commonly detected at autopsy in patients with acute nonlymphoblastic leukemia (ANLL), massive cardiac granulocytic sarcoma in the absence of bone marrow disease has not been previously described. Cytochemical and immunological methods of diagnosing granulocytic sarcoma in fixed tissues are reviewed.
Adult↗
Flow cytometry in lymphoma.
Explore the source record for details and available documents.
Antibodies, Monoclonal↗
Positive surface charge inhibition of phospholipase A2 in mixed monolayer systems.
Explore the source record for details and available documents.
Animals↗
Endoscopic "salvage" cytology in neoplasms metastatic to the upper gastrointestional tract.
Endoscopic "salvage" cytology was the only successful nonoperative diagnostic method in two patients with malignancy metastatic to the upper gastrointestinal tract. Smears and cell blocks of centrifuged material aspirated from the endoscope channel provided diagnoses of malignancies when other diagnostic techniques had been nonproductive. The results in these cases support the general utility of this technique and indicate its successful application in this specific clinical setting.
Aged↗