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Biomedical subjects

M Andreeff

Publications and source records attributed to M Andreeff.

At least 37 records · Page 2Linked to original sources
PubMed2000

Protein kinase inhibitors flavopiridol and 7-hydroxy-staurosporine down-regulate antiapoptosis proteins in B-cell chronic lymphocytic leukemia.

Compounds that inhibit protein kinases are currently undergoing clinical evaluation for the treatment of a variety of malignancies. The kinase inhibitors flavopiridol and 7 hydroxy-staurosporine (UCN-01) were examined for their effects on B-cell chronic lymphocytic leukemia (B-CLL) cells in vitro (n = 49). Flavopiridol and UCN-01 induced concentration-dependent apoptosis of most B-CLL samples tested, with greater than 50% cell killing occurring at concentrations of less than 1 mcmol/L, and with flavopiridol displaying more potent activity than UCN-01. Flavopiridol (0.1 mcmol/L) and UCN-01 (1 mcmol/L) also induced striking decreases in the levels of the antiapoptosis proteins Mcl-1, X-linked inhibitor of apoptosis (XIAP), and BAG-1 in nearly all cases of B-CLL and of Bcl-2 in approximately half of B-CLL specimens evaluated. In contrast, expression of the proapoptotic proteins Bax and Bak was not significantly influenced by these kinase inhibitors. Flavopiridol-induced decreases in the levels of antiapoptosis proteins Mcl-1 and XIAP preceded apoptosis and were not substantially affected by the addition of caspase inhibitors to cultures. In contrast, UCN-01-stimulated decreases in antiapoptosis proteins were slower, occurred concurrently with apoptosis, and were partially prevented by caspase inhibitors. The findings suggest that flavopiridol and UCN-01 induce apoptosis of B-CLL cells through different mechanisms. The potent apoptotic activities of flavopiridol and UCN-01 against cultured B-CLL cells suggest that they may be effective as single agents in the treatment of B-CLL or for sensitizing B-CLL cells to conventional cytotoxic drugs. (Blood. 2000;96:393-397)

Alkaloids↗
PubMed2000

Liposomal Bcl-2 antisense oligonucleotides enhance proliferation, sensitize acute myeloid leukemia to cytosine-arabinoside, and induce apoptosis independent of other antiapoptotic proteins.

The antiapoptotic proteins, Bcl-2 and Bcl-X(L), are expressed in most cases of acute myeloid leukemia (AML) and may contribute to drug resistance in AML. We tested the hypothesis that down-regulation of Bcl-2 alone by antisense oligodeoxynucleotides (Bcl-2-AS) induces apoptosis, even in the presence of other antiapoptotic genes. We tested Bcl-2-AS in myeloid leukemic HL-60 cells, in Bcl-2 and Bcl-X(L) overexpressing HL-60-DOX cells, and in primary AML samples. Down-regulation of Bcl-2 by Bcl-2-AS reduced the viability of HL-60 cells and, less effectively, HL-60-DOX cells and increased ara-C cytotoxicity in both cell lines. Incubation of primary AML blasts with Bcl-2-AS decreased Bcl-2 expression in CD34(+) blast cells after induction of apoptosis and enhancement of ara-C cytotoxicity in 11 of 19 primary AML samples. In 8 samples in which Bcl-2-AS did not induce apoptosis, baseline Bcl-2 levels were found to be strikingly high. The expression of other antiapoptotic proteins (Bcl-X(L), Bag-1, A1, and Mcl-1) did not prevent Bcl-2-AS-induced apoptosis. Bcl-2-AS also inhibited colony formation of AML progenitor cells. Low concentrations of Bcl-2-AS induced significant increases in S-phase cells (P =.04). Results establish Bcl-2 as a critical target for AS strategies in AML in which the baseline levels predict response to Bcl-2-AS. Bcl-2 exerts both antiapoptotic and antiproliferative functions in AML. Because early normal hematopoietic stem cells do not express Bcl-2, Bcl-2-AS therapy should be highly selective for AML cells. (Blood. 2000;95:3929-3938)

Acute Disease↗
PubMed2000

Cell-surface exposure of phosphatidylserine correlates with the stage of fludarabine-induced apoptosis in chronic lymphocytic leukemia and expression of apoptosis-regulating genes.

BACKGROUND: Programmed cell death (PCD) is characterized by a sequence of tightly regulated events that result in the activation of caspases and in internucleosomal DNA cleavage. Late apoptotic events such as DNA-strand breaks can be assayed by in situ end labeling (ISEL) and DNA measurement (sub G1) using flow cytometry. Phosphatidylserine (PS) redistribution from the inner plasma membrane leaflet to the outer leaflet, an early event in PCD, can be detected by annexin V (AxV) binding to PS. AxV-fluorescein isothiocyanate (FITC) fluorescence intensity is variable and characterizes different cell populations, denoted here as AxV-negative (AxV(neg)), AxV-low-positive (AxV(lo)), and AxV-high-positive (AxV(hi)). METHODS: We investigate the correlation of three methods (ISEL, sub G1 DNA content, and AxV assay) for detecting apoptosis with focus on differences between populations with different levels of PS. We also examined the expression of PCD-regulating Bcl-2 family members in these cell populations by reverse transcription-polymerase chain reaction (RT-PCR). Chronic lymphocytic leukemia (CLL) cells exposed to fludarabine (FAMP) were used as an in vitro model. Cells with different PS/AxV levels were separated using fluorescence-activated cell sorting (FACS). RESULTS: Only purified AxV(hi) cells had high positivity in the ISEL and sub G1 assays (94 +/- 0.6%, 88.6 +/- 6.6%, and 98.6 +/- 0.6%, respectively), indicating that late apoptotic cells are detected equally by all three methods. In the AxV(lo) population, ISEL was positive in 21% +/- 13% and DNA sub G1 in 20% +/- 6.6% of cells, suggesting that AxV identifies early apoptotic cells better than the other assays. Anti-apoptotic Bcl-2 and Bcl-X(L) were upregulated by FAMP when cells entered apoptosis (AxV(lo)), as was pro-apo- ptotic Bcl-X(S), which was undetectable in nonapoptotic AxV(neg) cells. Pro-apoptotic Bax was only expressed in AxV(neg) and AxV(lo) cells. Late apoptotic AxV(hi) cells did not express Bcl-X(S) or Bax. RESULTS: (1) AxV staining is more sensitive than sub G1 or ISEL in detecting early apoptotic cells; (2) only late apoptotic cells are equally detected by all assays; (3) AxV is a valuable tool in the detection and isolation of apoptotic cells at different stages of PCD; and (4) pro-apoptotic Bcl-X(S) and Bax are expressed at early, not late, stages of apoptosis.

Annexin A5↗
PubMed2000

Preparation and biodistribution of rhenium-188 labeled albumin microspheres B 20: a promising new agent for radiotherapy.

Intra-arterial infusion of labeled particles is an effective method for endoradiotherapy of tumors. In this study, we radiolabeled biodegradable HSA microspheres (mean diameter = 25 microm) with the short-lived beta-emitter 188Re available from the aluminia-based 188W/188Re generator system. After 1 h 35-40% of the relative large amount of Sn(II) chloride required for effective reduction of Re(VII) for efficient attachment to the particles is precipitated as an amorphous coat of tin hydroxid colloid on the particle surface. The final 188Re bound to the particles was found to be stable in vitro. The radiolabelling yield was > 90%. The biological half-life was > 250 h and demonstrated sufficient in vivo stability after i.v. injection in Wistar rats. Because of the attractive properties of 188Re and the uniform particle size and stability, in vivo, this new agent is an attractive candidate for endoradiotherapy of tumors after selective catheterization.

Albumins↗
PubMed2000

Adenovirus as a gene therapy vector for hematopoietic cells.

Adenovirus (Adv)-mediated gene transfer has recently gained new attention as a means to deliver genes for hematopoietic stem cell (HSC) or progenitor cell gene therapy. In the past, HSCs have been regarded as poor Adv targets, mainly because they lack the specific Adv receptors required for efficient and productive Adv infection. In addition, the nonintegrating nature of Adv has prevented its application to HSC and bone marrow transduction protocols where long-term expression is required. There is even controversy as to whether Adv can infect hematopoietic cells at all. In fact, the ability of Adv to infect epithelium-based targets and its inability to effectively transfect HSCs have been used in the development of eradication schemes that use Adv to preferentially infect and "purge" tumor cell-contaminating HSC grafts. However, there are data supporting the existence of productive Adv infections into HSCs. Such protocols involve the application of cytokine mixtures, high multiplicities of infection, long incubation periods, and more recently, immunological and genetic modifications to Adv itself to enable it to efficiently transfer genes into HSCs. This is a rapidly growing field, both in terms of techniques and applications. This review examines the two sides of the Adv/CD34 controversy as well as the current developments in this field.

Adenoviridae↗
PubMed2000

Results of treatment with hyper-CVAD, a dose-intensive regimen, in adult acute lymphocytic leukemia.

PURPOSE: To evaluate the efficacy and toxicity of Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone), a dose-intensive regimen, in adult acute lymphocytic leukemia (ALL). PATIENTS AND METHODS: Adults with newly diagnosed ALL referred since 1992 were entered onto the study; treatment was initiated in 204 patients between 1992 and January 1998. No exclusions were made because of older age, poor performance status, organ dysfunction, or active infection. Median age was 39.5 years; 37% were at least 50 years old. Mature B-cell disease (Burkitt type) was present in 9%, T-cell disease in 17%. Leukocytosis of more than 30 x 10(9)/L was found in 26%, Philadelphia chromosome-positive disease in 16% (20% of patients with assessable metaphases), CNS leukemia at the time of diagnosis in 7%, and a mediastinal mass in 7%. Treatment consisted of four cycles of Hyper-CVAD alternating with four cycles of high-dose methotrexate (MTX) and cytarabine therapy, together with intrathecal CNS prophylaxis and supportive care with antibiotic prophylaxis and granulocyte colony-stimulating factor therapy. Maintenance in patients with nonmature B-cell ALL included 2 years of treatment with mercaptopurine, MTX, vincristine, and prednisone (POMP). RESULTS: Overall, 185 patients (91%) achieved complete remission (CR) and 12 (6%) died during induction therapy. Estimated 5-year survival and 5-year CR rates were 39% and 38%, respectively. The incidence of CNS relapse was low (4%). Compared with 222 patients treated with vincristine, doxorubicin, and dexamethasone (VAD) regimens, our patients had a better CR rate (91% v 75%, P <.01) and CR rate after one course (74% v 55%, P <.01) and better survival (P <.01), and a smaller percentage had more than 5% day 14 blasts (34% v 48%, P =.01). Previous prognostic models remained predictive for outcome with Hyper-CVAD therapy. CONCLUSION: Hyper-CVAD therapy is superior to our previous regimens and should be compared with established regimens in adult ALL.

Adolescent↗
PubMed2000

E1A-mediated paclitaxel sensitization in HER-2/neu-overexpressing ovarian cancer SKOV3.ip1 through apoptosis involving the caspase-3 pathway.

HER-2/neu-overexpressing breast cancer cells are more resistant to the chemotherapeutic agent paclitaxel (Taxol) than low-HER-2/neu-expressing breast cancer cells, and the adenoviral type 5 EIA can down-regulate HER-2/neu overexpression. Therefore, in this study, we asked (a) whether EIA might sensitize response to paclitaxel in human HER-2/neu-overexpressing ovarian cancer cells, and, if so, what is the mechanism responsible; and (b) whether this enhanced chemosensitivity would translate into a therapeutic effect in an ovarian cancer xenograft model. Consequently, we demonstrated that: (a) adenovirus type 5 E1A could enhance the sensitivity of paclitaxel in paclitaxel-resistant HER-2/neu-overexpressing human ovarian cancer cells in vitro by inducing apoptosis, (b) this induction was heavily dependent on activation of the caspase-3 pathway, and (c) nude mice bearing i.p. HER-2/neu-overexpressing human ovarian cancer cells and treated with both paclitaxel and E1A gene therapy survived significantly longer than did mice treated only with paclitaxel or E1A gene therapy. Thus, we concluded that the E1A gene enhanced both the in vitro and in vivo sensitivity of paclitaxel in paclitaxel-resistant HER-2/ neu-overexpressing ovarian cancer SKOV3.ipl cells. Because a Phase I clinical trial using E1A gene targeted to HER-2/neu down-regulation has recently been completed, the current study also provided a scientific basis to further develop a novel therapy that combines paclitaxel and E1A gene therapy and its testing in a Phase II trial.

Adenovirus E1A Proteins↗
PubMed2000

BAX and PKCalpha modulate the prognostic impact of BCL2 expression in acute myelogenous leukemia.

Previously, we demonstrated that the level of BCL2 expression is prognostic in acute myelogenous leukemia (AML). High levels of BCL2 correlate with an adverse outcome when associated with favorable and intermediate prognosis cytogenetics (FIPC), whereas low levels portend an adverse outcome when associated with unfavorable cytogenetics (UC). Because BCL2 function can be modulated by dimerization with family members, like BAX, or by phosphorylation by protein kinase C alpha (PKCalpha), we hypothesize that the relative expression of these proteins in primary leukemic cells might alter the prognostic impact of BCL2 expression. We therefore measured BAX and PKCalpha protein levels in peripheral blood mononuclear cell lysates from 165 newly diagnosed AML patients and correlated the expression of these proteins with BCL2 expression, patient survival, and remission induction success. Expression levels of BAX and PKCalpha were normalized against a control cell line, K562. BAX and PKCalpha expression levels were heterogeneous and did not correlate with the percentage of blasts in the sample (R2 = 0.01 and <0.01). The median expression of both was similar across FAB groups but the range was greater for M4. A similar distribution of expression was observed in all cytogenetic groups, except that patients with inversion 16 demonstrated lower levels of BAX. Individually, neither PKCalpha nor BAX expression was prognostic of response to induction therapy or survival. A similar outcome was obtained when patients were stratified by cytogenetics into FIPC and UC groups. However, the ratio of either BCL2:BAX (B2:BX) or PKCalpha*B2:BX (PK*B2:BX) was highly prognostic. Patients with FIPC and a lower ratio (less than median) of either B2:BX or PK*B2:BX had a significantly higher remission induction rate (88 versus 69%, P = 0.04) and longer survival (median: 141 versus 80.5 weeks, P = 0.007) compared with those with ratios more than median. For patients with UC, values of either B2:BX or PK*B2:BX below the median had an inferior response rate to induction therapy (35 versus 78%, P = 0.0006) and inferior survival outcomes (median survival: 11 versus 53 weeks, P = 0.00002). Interestingly, FIPC and UC patients with antiapoptotic ratios (defined as B2:BX or PK*B2:BX more than median) had identical response rates and survival outcomes. In multivariate analyses, the compound variables of cytogenetics and B2:BX, or PK*B2:BX were independent predictors of survival. These results suggest that expression levels of proteins that affect the functional status of BCL2 modify the prognostic impact of BCL2 and suggest that the role of apoptosis in different cases of AML varies independently in the different cytogenetic subgroups.

Adolescent↗
PubMed2000

Expression and prognostic significance of IAP-family genes in human cancers and myeloid leukemias.

Expression of several inhibitor of apoptosis proteins (IAPs) was investigated in the National Cancer Institute panel of 60 human tumor cell lines, and the expression and prognostic significance of one of these, XIAP, was evaluated in 78 previously untreated patients with acute myelogenous leukemia (AML). XIAP and cIAP1 were expressed in most cancer lines analyzed, with substantial variability in their relative levels. In contrast, NAIP mRNA was not detectable, and cIAP2 was found at the mRNA and protein levels in only 34 (56%) and 5 (8%) of the 60 tumor cell lines analyzed, respectively. Interestingly, XIAP, cIAP1, and cIAP2 mRNA levels did not correlate with protein levels in the tumor lines, indicating posttranscriptional regulation of expression. High levels of XIAP protein in tumor cell lines were unexpectedly correlated with sensitivity to some anticancer drugs, particularly cytarabine and other nucleosides, whereas higher levels of cIAP1 protein levels were associated with resistance to several anticancer drugs. The relevance of XIAP to in vivo responses to cytarabine was explored in AML, making correlations with patient outcome (n = 78). Patients with lower levels of XIAP protein had significantly longer survival (median, 133 versus 52.5 weeks; P = 0.05) and a tendency toward longer remission duration (median, 87 versus 52.5 weeks; P = 0.13) than those with higher levels of XIAP. Altogether, these findings show that IAPs are widely but differentially expressed in human cancers and leukemias and suggest that higher XIAP protein levels may have adverse prognostic significance for patients with AML.

Gene Expression Regulation, Neoplastic↗
PubMed2000

Cytokine expression of T cells in chronic myeloid leukemia.

OBJECTIVE: To evaluate the function of T cells in chronic myeloid leukemia (CML). METHODS: Interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), interleukin-3 (IL-3), interleukin-4 (IL-4), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF alpha), and granulocyte macrophage-colony stimulating factor (GM-CSF) gene expressions were investigated by reverse transcription polymerase chain reaction (RT-PCR) assay in fluorescence active cell sorter (FACS) sorted peripheral blood CD2+/CD56-T cells from 12 CML patients, 10 meylodysplastic syndrome (MDS) patients and 7 normal individuals. RESULTS: TNF alpha mRNA was transcribed in T cells from all of the CML, MDS and normal individuals. IL-1 beta mRNA was transcribed in T cells from 10 CML, 9 MDS and 6 normal individuals. Low levels of IL-2 and IL-4 mRNA were detected in 5 CML patients. IL-3, IL-6 and GM-CSF mRNA were undetectable in all samples. CONCLUSION: IL-4 and IL-2 were expressed abnormally in T cells of CML.

Adult↗
PubMed1999

Sequential homoharringtonine and interferon-alpha in the treatment of early chronic phase chronic myelogenous leukemia.

Homoharringtonine (HHT) is a novel plant alkaloid that produced a complete hematologic remission (CHR) in 72% of patients with late chronic phase chronic myelogenous leukemia (CML). Cytogenetic (CG) remissions were noted in 31%. In this study, six courses of HHT were administered to 90 patients with early chronic phase CML (< 1 year from diagnosis). Patients then received interferon-alpha (IFN-alpha) with a target dose of 5 MU/m2 daily. Results were compared with those in a prior group of patients treated with IFN-alpha-based therapy between 1982 and 1990. Ninety-two percent of patients achieved CHR with HHT; CG responses were observed in 60% and were major in 27%. Both CHR and CG response rates were significantly higher than those seen in historical control patients after 6 months of IFN-alpha therapy. After receiving HHT, patients required lower doses of IFN-alpha to maintain a CHR. The median dose delivered was 2.4 MU/m2. This reduction in IFN-alpha dose was associated with a lower incidence of myalgia and gastrointestinal (GI) disturbances than that seen in patients treated at the 5 MU/m2 dose. Overall, CG responses were seen in 66% of the patients who received HHT and IFN-alpha compared with 61% of the historical control patients. HHT is a very effective treatment of early chronic phase CML, and ongoing trials are investigating the simultaneous administration of HHT and IFN-alpha, as well as that of HHT and low-dose cytosine arabinoside in patients failing IFN-alpha therapy.

Adult↗
PubMed1999

Randomized phase II study of fludarabine + cytosine arabinoside + idarubicin +/- all-trans retinoic acid +/- granulocyte colony-stimulating factor in poor prognosis newly diagnosed acute myeloid leukemia and myelodysplastic syndrome.

Preclinical data suggest that retinoids, eg, all-trans retinoic acid (ATRA), lower concentrations of antiapoptotic proteins such as bcl-2, possibly thereby improving the outcome of anti-acute myeloid leukemia (AML) chemotherapy. Granulocyte colony-stimulating factor (G-CSF) has been considered to be potentially synergistic with ATRA in this regard. Accordingly, we randomized 215 patients with newly diagnosed AML (153 patients) or high-risk myelodysplastic syndrome (MDS) (refractory anemia with excess blasts [RAEB] or RAEB-t, 62 patients) to receive fludarabine + ara-C + idarubicin (FAI) alone, FAI + ATRA, FAI + G-CSF, or FAI + ATRA + G-CSF. Eligibility required one of the following: age over 71 years, a history of abnormal blood counts before M.D. Anderson (MDA) presentation, secondary AML/MDS, failure to respond to one prior course of chemotherapy given outside MDA, or abnormal renal or hepatic function. For the two treatment arms containing ATRA, ATRA was given 2 days (day-2) before beginning and continued for 3 days after completion of FAI. For the two treatment arms including G-CSF, G-CSF began on day-1 and continued until neutrophil recovery. Patients with white blood cell (WBC) counts >50,000/microL began ATRA on day 1 and G-CSF on day 2. Events (death, failure to achieve complete remission [CR], or relapse from CR) have occurred in 77% of the 215 patients. Reflecting the poor prognosis of the patients entered, the CR rate was only 51%, median event-free survival (EFS) time once in CR was 36 weeks, and median survival time was 28 weeks. A Cox regression analysis indicated that, after accounting for patient prognostic variables, none of the three adjuvant treatment combinations (FAI + ATRA, FAI + G, FAI + ATRA + G) affected survival, EFS, or EFS once in CR compared with FAI. Similarly, there were no significant effects of either ATRA ignoring G-CSF, or of G-CSF ignoring ATRA. As previously found, a diagnosis of RAEB or RAEB-t rather than AML was insignificant. There were no indications that the effect of ATRA differed according to cytogenetic group, diagnosis (AML or MDS), or treatment schedule. Logistic regression analysis indicated that, after accounting for prognosis, addition of G-CSF +/- ATRA to FAI improved CR rate versus either FAI or FAI + ATRA, but G-CSF had no effect on the other outcomes. We conclude that addition of ATRA +/- G-CSF to FAI had no effect on CR rate, survival, EFS, or EFS in CR in poor prognosis, newly diagnosed AML or high-risk MDS.

Acute Disease↗
PubMed1999

Expression and function of leptin receptor isoforms in myeloid leukemia and myelodysplastic syndromes: proliferative and anti-apoptotic activities.

The receptor for the gene product of the obesity gene, leptin, was recently reported to be expressed on murine and human hematopoietic progenitor cells. Therefore, we studied the expression of the leptin receptor, OB-R, in normal myeloid precursors, human leukemia cell lines, and primary leukemic cells using reverse-transcriptase polymerase chain reaction. In normal hematopoiesis, OB-R was expressed in CD34(+) cells. Normal promyelocytes (CD34(-)33(+) and CD34(-)13(+)) expressed only very low levels of the short, presumably nonsignaling isoform. Both the long and short isoforms of OB-R were expressed in 10 of 22 samples from patients with newly diagnosed primary or secondary acute myeloid leukemia (AML), with a higher incidence of the long isoform in primary AML (87.6% v 28.6%; P =.01). The incidence of OB-R expression was higher in recurrent than in newly diagnosed AML (P <.001), and samples from four patients with refractory AML showed strong expression of both isoforms. Both OB-R isoforms were also expressed in newly diagnosed and recurrent acute promyelocytic leukemia cells but were essentially absent in samples of chronic or acute lymphocytic leukemia. In vitro growth of myeloid leukemic cell lines and of blasts from 14 primary AMLs demonstrated that recombinant human leptin alone induced low level proliferation, significantly (P <.05) increased proliferation induced by recombinant human granulocyte colony-stimulating factor, interleukin 3, and stem cell factor in a subset of AML and increased colony formation (P <.005). Also, leptin reduced apoptosis induced by cytokine withdrawal in MO7E and TF-1 cells. Serum leptin levels correlated only with body mass index (P <. 001) and gender (P =.03). Results confirm the reported expression of leptin receptor in normal CD34(+) cells and demonstrate the frequent expression of leptin receptors in AML blasts. While normal promyelocytes lack receptor expression, leukemic promyelocytes express both isoforms. We also demonstrate proliferative effects of leptin alone and in combination with other physiologic cytokines, and anti-apoptotic properties of leptin. These findings could have implications for the pathophysiology of AML.

Apoptosis↗
PubMed1999

Effective depletion of alloreactive lymphocytes from peripheral blood mononuclear cell preparations.

BACKGROUND: T cells present in an allogeneic bone marrow transplant may produce graft-versus-host disease but also contribute to immune reconstitution and enhance engraftment. Our aim was to separate alloreactive from nonalloreactive T lymphocytes, by performing a mixed lymphocyte culture (MLC) stimulation of donor cells, followed by selective depletion of activated cells expressing the high-affinity interleukin 2 receptor. We then characterized the resulting depleted cell fraction. METHODS: Donor peripheral blood mononuclear cells were cocultured with irradiated peripheral blood mononuclear cells from HLA-nonidentical recipient stimulators in an MLC. After 3 days, CD25+ lymphocytes (alloreactive cells expressing the alpha chain of the interleukin 2 receptor) were removed by immunomagnetic separation. The depleted donor fraction and untreated cells were then rechallenged in a secondary MLC with the original irradiated stimulator cells or a third party to assess relative alloreactivity. RESULTS: Inhibition of the secondary MLC and of host-specific cytotoxic activities was observed as well as a disappearance of interleukin 2 receptor-positive cells. Alloreactivity against unrelated third-party cells was preserved. Limiting dilution analysis of residual alloantigen-reactive T lymphocytes demonstrated a 1.3 log reduction of antihost reactivity. The depletion largely removed host-specific alloreactive CD4+ cells. CONCLUSIONS: This method reduces alloreactivity while retaining reactivity against third-party targets. This approach may allow therapeutic infusion of T cells after HLA-nonidentical allografts with a reduced capacity to produce graft-versus-host disease.

Blood Component Removal↗
PubMed1999

Interleukin-10 levels are often elevated in serum of adults with Hodgkin's disease and are associated with inferior failure-free survival.

BACKGROUND: Interleukin-10 (IL-10) is a pleiotropic cytokine that protects B- or T-lymphocytes and hemopoietic progenitors from apoptosis induced by doxorubicin, glucocorticoids, or deprivation of growth factors. IL-10 is also immunosupressive, and tumor cells secreting IL-10 can grow in syngeneic or allogeneic hosts, and can inhibit the generation of tumor-specific cytotoxic T cells. Hodgkin-Reed-Sternberg cells are derived from follicular center B cells and they may be latently infected by EBV. When this occurs they often express IL-10. Based on these considerations we investigated the relationship between pretreatment serum IL-10 levels and failure-free survival (FFS) in Hodgkin's disease (HD). PATIENTS AND METHODS: Untreated patients, older than 16 years, with biopsy-proven HD, were included if treated with ABVD or equivalent regimens, and if pretreatment serum was available. IL-10 levels were determined with a capture enzyme-linked immunoassay specific for cellular IL-10. RESULTS: Among healthy adult volunteers serum IL-10 levels ranged from 4.8-9.8 pg/ml (mean 7.1, standard deviation 1.5 pg/ml). Therefore levels > or = 10 pg/ml were considered elevated. We identified 101 patients with available serum. Their median age was 32 years, and 60% had B-symptoms. Ann Arbor stage was I in 4, II in 21, III in 35, and IV in 41 patients. Histology was nodular sclerosis in 74, mixed cellularity in 12, lymphocyte predominance in six, lymphocyte depletion in one, and unclassified in eight patients. Pretreatment serum IL-10 levels were elevated in 51 patients, and were higher in those with serum albumin < 3.5 g/dl, B symptoms, serum beta 2-microglobulin > or = 2.5 mg/l, anemia, and AAS III or IV. After a median follow-up of 32 months for survivors, 20 patients have progressed, and the three-year FFS of those with high vs. normal serum IL-10 was 60% +/- 9 vs. 91 +/- 9% (50% vs. 50% of the population; P = 0.004 by log-rank). Among patients with Ann Arbor stage III or IV the three-year FFS for those with high vs. normal serum IL-10 (58 vs. 42% of the population) was 57 +/- 9% vs. 92 +/- 6% (P = 0.008 by log-rank). Multivariate analysis using Cox's proportional hazards model confirmed that IL-10 was an independent variable associated with inferior FFS in this population. CONCLUSIONS: Elevation of serum IL-10 levels is frequent and is associated with inferior FFS in adults with ABVD-treated HD. This observation should be verified in other patient populations. In addition, the source and the role of IL-10 in the biology of HD should be further investigated.

Adolescent↗
PubMed1999

Quantitation of minimal residual disease in acute myelogenous leukemia and myelodysplastic syndromes in complete remission by molecular cytogenetics of progenitor cells.

Detection of karyotypic clonal abnormalities are prognostically useful in patients with acute myelogenous leukemia (AML) and myelodysplastic syndromes (MDS), but cytogenetic methods are not sensitive enough to detect low numbers of residual leukemic cells in patients who have achieved complete remission (CR). Fluorescence in situ hybridization (FISH) and fluorescence activated cell sorting (FACS) were used to investigate the frequency and presence of minimal residual disease (MRD) in AML and MDS patients (n = 28) with monosomy of chromosomes 7, 17 and 18 and trisomy of chromosomes 6, 8, 9 and 10 in CR. MRD was detected in all patients with monosomy 7 (n = 10) and followed by relapse in eight patients after 4.8 +/- 3.1 months. In contrast, persistent leukemic cells occurred in 11/12 patients with trisomy 8, but only three of them relapsed after 7.7 +/- 4.0 months. Cox regression analysis showed that cytogenetic class and levels of clonal cells at CR were related to time to relapse (P = 0.001). The level of MRD identified patients at high and low risk of relapse. High absolute levels of proliferating residual leukemic cells correlated with monosomy 7 and high risk of relapse.

Acute Disease↗
PubMed1999

Expression of Bcl-2-related genes in normal and AML progenitors: changes induced by chemotherapy and retinoic acid.

The expression of Bcl-2 family members was examined in normal and leukemic hematopoietic cells. Immature hematopoietic progenitor cells (CD34+/33-/13-) did not express Bcl-2 but Bcl-XL, the majority of CD34 cells expressed Bcl-2, Bcl-XL and BAD, and normal promyelocytes (CD34-/33+) lacked expression of both Bcl-2 and Bcl-XL, while leukemic CD34+progenitors and promyelocytes expressed these anti-apoptotic proteins. In AML, Bcl-2 expression was higher on CD34+ than on all AML cells, however, expression of Bcl-2 or Bcl-XL did not predict achievement of complete remission. Surprisingly, low Bcl-2 content was associated with poor survival in a group of patients with poor prognosis cytogenetics. The anti-apoptotic BAD protein was found to be expressed in AML, but was phosphorylated in 41/42 samples. Phosphorylation was found at both sites, Ser 112 and Ser 136. During induction chemotherapy, Bcl-2 levels of CD34 cells increased significantly. In the context of evidence for small numbers of leukemic CD34+ cells expressing very high levels of Bcl-2 prior to therapy, this finding is interpreted as a survival advantage of Bcl-2 overexpressing progenitors and rapid elimination of cells with low Bcl-2. Bcl-2 and Bcl-XL were both expressed in minimal residual disease cells. Downregulation of Bcl-2 mRNA and protein was observed by ATRA and the combination of Ara-C, followed by ATRA, resulted in markedly increased cytotoxicity in HL-60 cells, as compared to Ara-C alone or ATRA followed by Ara-C. Implications of these findings for the development of new therapeutic strategies for AML are discussed.

Acute Disease↗