Platelet factor-4 is an indicator of blood count recovery in acute myeloid leukemia patients in complete remission

To investigate whether serum biomarkers can be used to indicate the responsiveness of acute myeloid leukemia to remission induction chemotherapy, we performed MALDI-TOF protein profile analysis of patient sera. The resulting spectra revealed a protein (or peptide) peak at m/z 7764 that varied in intensity; its intensity was much higher in samples from patients in complete remission than in those from patients with resistant disease or in samples taken prior to treatment (at the time of diagnosis). Using fractionation, trypsin digestion, MS/MS, and protein molecular weight analyses, we identified the m/z 7764 protein as platelet factor-4 (PF4). This identification was confirmed by a magnetic bead-based MALDI immunoassay. Statistical comparison of PF4 levels and platelet counts in patient sera revealed a significant positive correlation between the two variables. This study demonstrates that PF4 protein levels are a good indicator for the recovery of blood count in the complete remission of acute myeloid leukemia. The linear positive correlation curve indicates that blood count recovery of platelets to >100,000/mm(3) is equivalent to a serum PF4 recovery level of >2.492 microg/ml.     

CFU-gm colony formation of peripheral blood and bone marrow in adult acute leukemia at presentation, during remission, and at relapse

Granulocyte/macrophage colony-forming unit (CFU-gm) formation was studied simultaneously in bone marrow and peripheral blood of 52 previously untreated adult patients with acute non-lymphocytic (ANLL) and 36 with acute lymphoblastic leukemia (ALL). They were followed during induction therapy at monthly intervals while in remission and in 19 ANLL and 22 ALL cases, until relapse. Patients showing a decreased colony number in the marrow but normal or increased colony numbers in the peripheral blood had a high probability of entering remission. Non-responding patients displayed an opposite pattern. The higher the degree of marrow repopulation with granulocytic progenitor cells after induction treatment, the longer remission duration and survival for ANLL patients and the longer survival for ALL patients. CFU-gm formation returned to normal in the early stages of complete remission, but then declined progressively. At ANLL and ALL relapse, colony growth was reduced markedly while cluster formation remained normal. The number of marrow colonies and clusters in ANLL were significantly higher at first and second relapse compared to the growth pattern at first presentation. A similar trend had been observed in ALL, suggesting a selection advantage.     

DNA methylation analysis of bone marrow cells at diagnosis of acute lymphoblastic leukemia and at remission

To detect genes with CpG sites that display methylation patterns that are characteristic of acute lymphoblastic leukemia (ALL) cells, we compared the methylation patterns of cells taken at diagnosis from 20 patients with pediatric ALL to the methylation patterns in mononuclear cells from bone marrow of the same patients during remission and in non-leukemic control cells from bone marrow or blood. Using a custom-designed assay, we measured the methylation levels of 1,320 CpG sites in regulatory regions of 413 genes that were analyzed because they display allele-specific gene expression (ASE) in ALL cells. The rationale for our selection of CpG sites was that ASE could be the result of allele-specific methylation in the promoter regions of the genes. We found that the ALL cells had methylation profiles that allowed distinction between ALL cells and control cells. Using stringent criteria for calling differential methylation, we identified 28 CpG sites in 24 genes with recurrent differences in their methylation levels between ALL cells and control cells. Twenty of the differentially methylated genes were hypermethylated in the ALL cells, and as many as nine of them (AMICA1, CPNE7, CR1, DBC1, EYA4, LGALS8, RYR3, UQCRFS1, WDR35) have functions in cell signaling and/or apoptosis. The methylation levels of a subset of the genes were consistent with an inverse relationship with the mRNA expression levels in a large number of ALL cells from published data sets, supporting a potential biological effect of the methylation signatures and their application for diagnostic purposes.     

Spontaneous remission from acute exacerbation of chronic adult T-cell leukemia

Spontaneous remission without any anti-cancer therapy in a 57-year-old woman with adult T-cell leukemia (ATL) is reported. The patient was referred to our department because of persistent cough and appearance of abnormal lymphocytes in the peripheral blood, and she was diagnosed as having chronic ATL. Eight months later, she was re-admitted because of cystitis, watery diarrhea and worsening of respiratory symptoms with an increase of ATL cells (WBC 31 x 10(9)/l with 56% ATL cells). Acute exacerbation of ATL was diagnosed. Interestingly, antibiotic therapy for the pulmonary and urinary tract infections brought about spontaneous reduction of the ATL cell count. Spontaneous remission of ATL continued for one year without chemotherapy. The role of infection as a trigger of acute exacerbation and spontaneous remission of ATL is discussed.     

Comparison analysis between haplo identical stem cell transplantation and matched sibling donor stem cell transplantation for high-risk acute myeloid leukemia in first complete remission

In order to compare the effect between haploidentical(HID) stem cell transplantation(HSCT) and matched sibling donor(MSD)stem cell transplantation for high-risk acute myeloid leukemia(AML) in first complete remission status(CR1), we retrospectively studied 170 cases who received stem cell transplantation from Jan 2008 to Jul 2015 in Peking University People's Hospital. We divided all cases into MSD group(43 cases) and HID(127 cases) group. Patients in HID and MSD group displayed similar baseline characteristics except for age distribution. There were no statistic differences for overall survival(OS), cumulative incidence of relapse, leukemia free survival(LFS), transplantation related mortality(TRM) between HID and MSD group. The 3-year OS, LFS for all patients was 63.9% and 59.7% respectively. Multivariate analysis showed that grade III-IV acute graft versus host disease(aGVHD) was an independent risk factor for treatment related mortality(HR=8.134, 95% CI:3.210–20.611, P0.001), monosomy/complex chromosomal karyotype and white blood cell count more than 50×109 L-1 were two independent factors for relapse(HR=1.533, 95% CI: 1.040–2.260, P=0.031)(HR=1.004, 95% CI: 1.001–1.008, P=0.015).Grade III-IV aGVHD was an independent factor for mortality(HR=3.184, 95% CI: 1.718–5.902, P0.001). These results demonstrated some risk factors for high-risk AML leukemia transplantation and indicated for AML patients in CR1 status, haplo stem cell transplantation could have the same therapeutic effect as MSD transplantation.     

Targeting leukemia stem cells: The new goal of therapy in adult acute myeloid leukemia

The most popular view of hematopoietic cell lineage organization is that of complex reactive or adaptative systems. Leukemia contains a subpopulation of cells that display characteristics of stem cells. These cells maintain tumor growth. The properties of leukemia stem cells indicate that current conventional chemotherapy, directed against the bulk of the tumor, will not be effective. Leukemia stem cells are quiescent and do not respond to cell cycle-specific cytotoxic agents used to treat leukemia and thus contribute to treatment failure. New strategies are required that specifically target this malignant stem cell population.     

Risk of adult acute and chronic myeloid leukemia with cigarette smoking and cessation

BackgroundCigarette smoking is an established risk factor for adult myeloid leukemia, particularly acute myeloid leukemia (AML), but less is known about the nature of this association and effects of smoking cessation on risk.MethodsIn a large population-based case–control study of myeloid leukemia that included 414 AML and 185 chronic myeloid leukemia (CML) cases and 692 controls ages 20–79 years, we evaluated risk associated with cigarette smoking and smoking cessation using unconditional logistic regression methods and cubic spline modeling.ResultsAML and CML risk increased with increasing cigarette smoking intensity in men and women. A monotonic decrease in AML risk was observed with increasing time since quitting, whereas for CML, the risk reduction was more gradual. For both AML and CML, among long-term quitters (≥30 years), risk was comparable to non-smokers.ConclusionsOur study confirms the increased risk of myeloid leukemia with cigarette smoking and provides encouraging evidence of risk attenuation following cessation.     

In vitro culture studies of blood and marrow cells in chronic myeloid leukemia at different phases of the disease

The in vitro culture growth of peripheral blood (PB) and bone marrow (BM) cells were studied simultaneously from 100 adult patients with chronic myeloid leukemia at different phases. Sixty-five patients were investigated at initial diagnosis, 30 patients in control phase, and 41 patients in blast phase. In untreated chronic phase, the relative concentrations of granulocyte-macrophage progenitor cells (CFU-GM) in BM were not significantly different from those of normal controls, but there was generally a marked increase in circulating CFU-GM. The 6 Ph1-negative patients did not show different growth characteristics. We were unable to correlate the CFU-GM number to any of the hematologic parameters as well as to the response to busulfan therapy. Pretreated patients with excessive cluster formation did not necessarily indicate impending blast crisis. In hematologic remission, the numbers of CFU-GM in both BM and PB were well within the ranges of normal controls. Culture results in blast phase revealed a spectrum of abnormal growth. In myeloid crisis, 14/29 BM and 12/29 PB samples showed increased colony and cluster formations which were composed predominantly of immature cells with variable degeneration. Marrow cells in lymphoid crisis produced low numbers of both colonies and clusters in 5 out of 8 patients, while blood cells from 8 out of 10 patients formed large amount of colonies of normal morphology. This study indicates that the in vitro CFU-GM assay may have diagnostic utility in differentiating lymphoid crisis from myeloid crisis.     

Prolonged remission maintenance in acute myeloid leukaemia.

Twenty-five patients with acute myeloid leukaemia were treated with three quadruple drug combinations in predetermined rotation: TRAP (thioguanine, daunorubicin, cytarabine, prednisolone); COAP (cyclophosphamide, vincristine, cytarabine, prednisolone); and POMP (prednisolone, vincristine, methotrexate, mercaptopurine). Fifteen patients (60%) achieved complete remission and five (20%) partial remission. For maintenance, five-day courses of drugs were administered every 14 to 21 days and doses were increased to tolerance. The median length of complete remission was 66 weeks. In eight patients remission maintenance treatment was discontinued and some remained in complete remission for over two years. In this series the remission induction rate was comparable with that reported for other regimens and complete remission lasted longer with this intensive maintenance regimen than with others. Nevertheless, the TRAP programme must still be regarded as only palliative treatment for acute myeloid leukaemia.     

Annular promyelocytes in acute myeloid leukemia

Granulocytes with ring-shaped nuclei (annular granulocytes; ring granulocytes) are normal bone marrow constituents in rodents. Studies in man have shown a small number of these cells in cases of myeloproliferative diseases. Myelocytes and metamyelocytes have also been described. Similar to rodents and some other animal species, the annular promyelocyte also exists in humans. The significance of these very rare cells in human haemopoiesis becomes an interesting question.     

Interleukin-17 in acute myeloid leukemia

There are several reports that angiogenesis plays important roles in hematological malignancies including acute myeloid leukemia (AML). Human interleukin-17 (IL-17) is a proinflammatory cytokine produced by activated CD4 T cells. IL-17 plays a potential role in T cell mediated angiogenesis. The role of IL-17 in pathologic angiogenesis has not been evaluated yet. The aim of the study was to determine plasma level of IL-17 in patients with AML. IL-17 levels were measured by ELISA in plasma samples taken from 68 adult patients with AML before chemotherapy was administered. In addition 20 out of 68 patients were reanalysed after achieving complete remission (CR). Ten samples from healthy volunteers were evaluated as the control. In this study we have demonstrated that serum level of IL-17 is not elevated in AML patients. These results suggest that angiogenesis in AML is not mediated by CD4 T cells. To our knowledge this is the first report about IL-17 serum level in acute leukemias. We are currently evaluating IL-17 levels in others haematological malignancies.     

Studies of natural killer cell activity and antibody-dependent cell-mediated cytotoxicity among patients with acute leukemia in complete remission

Summary Low natural killer (NK) cell activity against the K-562 leukemia cell line was observed in patients with acute leukemia in the early stages of remission, i.e., 2–4 months (11.3%±7.95% specific target cell lysis). This parameter was found to be normal among leukemia patients after a longer time in remission (19.53%±7.55%) when compared with healthy donors (18.46%±12.98%). A similar pattern of activity was observed in studies of antibody-dependent cell-mediated cytolysis (ADCC) to the CEM lymphoid tumor cell line in the same group (37.58%±12.4% vs. 51%±6.79% specific target cell lysis).ADCC to chicken red blood cells (CRBC) and to human red blood cells (HRBC) was not significantly different from that for healthy controls at either duration of remission.Nine patients relapsed over a follow-up period of 9 months. They were found to have slightly lower NK activity (14.4%±9.3%) and ADCC to CEM (41.4%±8.5%) than the patients who remained in remission (17.1%±6.8%; 48.7%±9.7%, respectively).These data indicate a lymphocyte deficit which may persist for some time after remission has been induced, and which may be due to the effect of leukemic cell burden or the effect of aggressive chemotherapy.