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1.
Cytometry B Clin Cytom ; 106(1): 11-24, 2024 01.
Article in English | MEDLINE | ID: mdl-38345160

ABSTRACT

The 5-azacytidine (AZA) and decitabine (DEC) are noncytotoxic, differentiation-inducing therapies approved for treatment of myelodysplastic syndrome, acute myeloid leukemias (AML), and under evaluation as maintenance therapy for AML postallogeneic hematopoietic stem cell transplant and to treat hemoglobinapathies. Malignant cell cytoreduction is thought to occur by S-phase specific depletion of the key epigenetic regulator, DNA methyltransferase 1 (DNMT1) that, in the case of cancers, thereby releases terminal-differentiation programs. DNMT1-targeting can also elevate expression of immune function genes (HLA-DR, MICA, MICB) to stimulate graft versus leukemia effects. In vivo, there is a large inter-individual variability in DEC and 5-AZA activity because of pharmacogenetic factors, and an assay to quantify the molecular pharmacodynamic effect of DNMT1-depletion is a logical step toward individualized or personalized therapy. We developed and analytically validated a flow cytometric assay for DNMT1 epitope levels in blood and bone marrow cell subpopulations defined by immunophenotype and cell cycle state. Wild type (WT) and DNMT1 knock out (DKO) HC116 cells were used to select and optimize a highly specific DNMT1 monoclonal antibody. Methodologic validation of the assay consisted of cytometry and matching immunoblots of HC116-WT and -DKO cells and peripheral blood mononuclear cells; flow cytometry of H116-WT treated with DEC, and patient samples before and after treatment with 5-AZA. Analysis of patient samples demonstrated assay reproducibility, variation in patient DNMT1 levels prior to treatment, and DNMT1 depletion posttherapy. A flow-cytometry assay has been developed that in the research setting of clinical trials can inform studies of DEC or 5-AZA treatment to achieve targeted molecular pharmacodynamic effects and better understand treatment-resistance/failure.


Subject(s)
Leukemia, Myeloid, Acute , Leukocytes, Mononuclear , Humans , Decitabine/pharmacology , Decitabine/therapeutic use , Flow Cytometry , Reproducibility of Results , Azacitidine/pharmacology , Azacitidine/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , Biomarkers
2.
Semin Hematol ; 58(1): 45-55, 2021 01.
Article in English | MEDLINE | ID: mdl-33509443

ABSTRACT

The DNA methyltransferase inhibitor azacytidine (aza) may reactivate pathways associated with plasma cell differentiation, cell cycle control, apoptosis, and immune recognition and thereby restore sensitivity to lenalidomide (len) and dexamethasone (dex) in relapsed and/or refractory multiple myeloma (RRMM). We aimed to develop an aza regimen that reaches epigenetically active levels 8 times in 28 days with less bone marrow toxicity than the myeloid malignancy standard of 7 consecutive doses to enable safe combination with len. Aza was escalated from 30 mg/m2 once a week up to a predefined maximum of 50 mg/m2 twice a week in combination with GFR-adjusted len (≥ 60 mL/min: 25 mg, 3059 mL/min: 10 mg) day 1 to 21 every 28 days and dex 40 mg once a week followed by a limited expansion study to a total N of 23 at the highest tolerated dose. Fifty-one patients (pts) with RRMM were screened, 42 were treated and 41 were evaluable for response based on at least 1 response assessment or progression after treatment start. The median number of prior lines of therapy was 5 (1-11) and 81% (34) were refractory to len and/or pomalidomide (pom). Two DLTs occurred in different cohorts, 1 neutropenic fever in 1/6 pts on the aza 40 mg/m2 twice a week GFR ≥ 60 mL/min cohort and 1 GGT elevation in 1/6 pts on the aza 50 mg/m2 GFR 30-59 mL/min cohort. An MTD was not reached and aza 50 mg/m2 SC twice a week was chosen for the expansion study. At least possibly related Grade 3/4 AEs occurred in 28 pts (67%) with the following in > 1 pt: neutropenia (N = 16, 38%), anemia (N = 6, 14%), lymphopenia (N = 5, 12%), thrombocytopenia (N = 4, 10%), leukopenia (N = 4, 10%), febrile neutropenia (N = 4, 10%), fatigue (N = 3, 7%), fever (N = 2, 5%), and infection (N = 2, 5%). At a median follow up time for alive pts of 60.2 months (range: 36.1-82.5 months), the overall response rate (≥ partial response) and clinical benefit response rate (≥ minor response) was 22 and 32%, respectively, with 4 very good partial responses (10%), 5 partial responses (12%), and 4 minor responses (10%). The median PFS was 3.1 months (95% confidence interval [CI]: 2.1-5.1 months), median TTP 2.7 months (95% CI: 2.1-7.5 months), and median OS 18.6 months (95% CI: 12.9-33.0 months). Achieving at least minor response and reaching TTP > 6 months was associated with approximately 35% lower median plasma levels of the enzyme that inactivates aza, plasma cytidine deaminase (CDA, P< .0001). Two of the len refractory pts achieved longer disease control than with any prior regimen and 1 responded immediately after progression on len, bortezomib, and prednisone. Analyses of the methylation state of over 480,000 CpG sites in purified myeloma cells at screening were possible in 11 pts and on day 28 in 8 of them. As in other studies, the majority of differentially methylated CpGs compared to normal plasma cells were hypomethylated in myeloma. Treatment decreased the number of CpGs that were differentially methylated in normal plasma cells by > 0.5% in 6 and by > 5% in 3 of the 8 pts, most pronounced in 2 pts with clinically convincing aza contribution who achieved a reduction in overall differentially methylated CpGs by 23 and 68%, respectively, associated with increased expression of immunoglobulin genes. The study demonstrated tolerability of twice a week SC aza at 50 mg/m2 with len and dex in RRMM and suggested aza may help overcome the len/pom refractory state, possibly by activating differentiation pathways. Relatively low response rates and association of clinical benefit with low plasma levels of the aza inactivating enzyme CDA suggest the aza regimen will need to be optimized further and pt selection may be required to maximize benefit.


Subject(s)
Multiple Myeloma , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Azacitidine/adverse effects , DNA Methylation , Dexamethasone/adverse effects , Humans , Lenalidomide/pharmacology , Lenalidomide/therapeutic use , Multiple Myeloma/drug therapy , Multiple Myeloma/genetics , Treatment Outcome
3.
Br J Haematol ; 189(2): 318-322, 2020 04.
Article in English | MEDLINE | ID: mdl-31958160

ABSTRACT

T-cell large granular lymphocytic leukaemia (T-LGLL) is a chronic clonal lymphoproliferative disorder of cytotoxic T lymphocytes which commonly occurs in older patients and is often associated with autoimmune diseases. Among 246 patients with T-LGLL seen at our institution over the last 10 years, we encountered 15 cases following solid organ or haematopoietic stem cell transplantation. Here, we studied the clinical characterization of these cases and compared them to de novo T-LGLL. This experience represented a clear picture of the intricate nature of the disease manifestation and the complexities of several immune mechanisms triggering the clonal expansion.


Subject(s)
Hematopoietic Stem Cell Transplantation/adverse effects , Leukemia, Large Granular Lymphocytic/etiology , Transplantation Conditioning/adverse effects , Adolescent , Adult , Female , Humans , Leukemia, Large Granular Lymphocytic/pathology , Male , Middle Aged
4.
Br J Haematol ; 188(6): 924-929, 2020 03.
Article in English | MEDLINE | ID: mdl-31736067

ABSTRACT

The nucleoside analogue decitabine can deplete the epigenetic regulator DNA methyltransferase 1 (DNMT1), an effect that occurs, and is saturated at, low concentrations/doses. A reason to pursue this molecular-targeted effect instead of the DNA damage/cytotoxicity produced with high concentrations/doses, is that non-cytotoxic DNMT1-depletion can cytoreduce even p53-null myeloid malignancies while sparing normal haematopoiesis. We thus identified minimum doses of decitabine (0·1-0·2 mg/kg) that deplete DNMT1 without off-target anti-metabolite effects/cytotoxicity, and then administered these well-tolerated doses frequently 1-2X/week to increase S-phase dependent DNMT1-depletion, and used a Myeloid Malignancy Registry to evaluate long-term outcomes in 69 patients treated this way. Consistent with the scientific rationale, treatment was well-tolerated and durable responses were produced (~40%) in genetically heterogeneous disease and the very elderly.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Decitabine/therapeutic use , Myeloproliferative Disorders/drug therapy , Aged , Aged, 80 and over , Antimetabolites, Antineoplastic/pharmacology , Decitabine/pharmacology , Female , Humans , Male
5.
Br J Haematol ; 185(5): 935-939, 2019 06.
Article in English | MEDLINE | ID: mdl-30891747

ABSTRACT

Compound heterozygous germline mutations in CTC1 gene have been found in patients with atypical dyskeratosis congenita (DC), whereas heterozygous carriers are unaffected. Through screening of a large cohort of adult patients with acquired bone marrow failure syndromes, in addition to a DC case, we have also found extremely rare or novel heterozygous deleterious germline variants of CTC1 in patients with aplastic anaemia (AA; n = 5), paroxysmal nocturnal haemoglobinuria (PNH; n = 3) and myelodysplastic syndrome (MDS; n = 2). A compound heterozygous case of AA showed clonal evolution. Our results suggest that some of the inherited CTC1 variants may represent predisposition factors for acquired bone marrow failure.


Subject(s)
Bone Marrow Failure Disorders/genetics , Germ-Line Mutation , Telomere-Binding Proteins/genetics , Telomere/genetics , Adult , Aged , Aged, 80 and over , Bone Marrow Failure Disorders/metabolism , Bone Marrow Failure Disorders/pathology , Female , Humans , Male , Middle Aged , Telomere/metabolism , Telomere/pathology , Telomere-Binding Proteins/metabolism
6.
J Clin Invest ; 128(10): 4260-4279, 2018 10 01.
Article in English | MEDLINE | ID: mdl-30015632

ABSTRACT

Nucleophosmin (NPM1) is among the most frequently mutated genes in acute myeloid leukemia (AML). It is not known, however, how the resulting oncoprotein mutant NPM1 is leukemogenic. To reveal the cellular machinery in which NPM1 participates in myeloid cells, we analyzed the endogenous NPM1 protein interactome by mass spectrometry and discovered abundant amounts of the master transcription factor driver of monocyte lineage differentiation PU.1 (also known as SPI1). Mutant NPM1, which aberrantly accumulates in cytoplasm, dislocated PU.1 into cytoplasm with it. CEBPA and RUNX1, the master transcription factors that collaborate with PU.1 to activate granulomonocytic lineage fates, remained nuclear; but without PU.1, their coregulator interactions were toggled from coactivators to corepressors, repressing instead of activating more than 500 granulocyte and monocyte terminal differentiation genes. An inhibitor of nuclear export, selinexor, by locking mutant NPM1/PU.1 in the nucleus, activated terminal monocytic fates. Direct depletion of the corepressor DNA methyltransferase 1 (DNMT1) from the CEBPA/RUNX1 protein interactome using the clinical drug decitabine activated terminal granulocytic fates. Together, these noncytotoxic treatments extended survival by more than 160 days versus vehicle in a patient-derived xenotransplant model of NPM1/FLT3-mutated AML. In sum, mutant NPM1 represses monocyte and granulocyte terminal differentiation by disrupting PU.1/CEBPA/RUNX1 collaboration, a transforming action that can be reversed by pharmacodynamically directed dosing of clinical small molecules.


Subject(s)
Granulocytes/metabolism , Leukemia, Myeloid, Acute/metabolism , Monocytes/metabolism , Mutation , Neoplasm Proteins/metabolism , Nuclear Proteins/metabolism , Transcription Factors/metabolism , Animals , Granulocytes/pathology , Heterografts , Humans , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , Mice , Monocytes/pathology , Neoplasm Proteins/genetics , Neoplasm Transplantation , Nuclear Proteins/genetics , Nucleophosmin , THP-1 Cells , Transcription Factors/genetics
7.
Mycoses ; 61(5): 321-325, 2018 May.
Article in English | MEDLINE | ID: mdl-29314351

ABSTRACT

Most superficial mycotic infections of human skin are due to dermatophytes. Children are frequently affected due to different predisposing factors, particularly overcrowding in classrooms. This study aimed to estimate the prevalence of dermatophytes infections and their related risk factors among school children in Menoufia Governorate, Egypt. Six public primary and preparatory schools were randomly selected and their pupils (n = 3464) were asked to complete a predesigned questionnaire covering both personal data and suspected risk factors for superficial dermatophyte infections. The children were also examined for dermatological diseases. Any suspected lesions were biopsied for mycological examination. The prevalence of clinically suspected dermatophytes infections was 1.41%, whereas the prevalence of culture confirmed cases was 0.98%. The most common clinical type was tinea capitis with a prevalence of 1.01%. Microsporum canis was the only isolated organism from the suspicious lesions with a 69.4% positivity rate. A higher prevalence was observed among boys, low socio-economic pupils and those with a family history of dermatophyte infections. Pet contact and sharing towels and caps among pupils were significant risk factors. Dermatophyte infection is still prevalent among basic school pupils. Fortunately, it is related to preventable risk factors. We recommend regular screening and use of educational health programmes for kids to control it.


Subject(s)
Arthrodermataceae/isolation & purification , Dermatomycoses/epidemiology , Students , Tinea Capitis/epidemiology , Adolescent , Animals , Arthrodermataceae/classification , Biopsy , Child , Cohort Studies , Crowding , Dermatomycoses/microbiology , Dermatomycoses/prevention & control , Egypt/epidemiology , Female , Humans , Male , Microsporum/isolation & purification , Pets , Prevalence , Risk Factors , Schools , Skin/pathology , Surveys and Questionnaires , Tinea Capitis/microbiology , Trichophyton/isolation & purification
9.
Korean J Pain ; 30(2): 134-141, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28416997

ABSTRACT

BACKGROUND: Postoperative pain is a common, distressing symptom following arthroscopic knee surgery. The aim of this study was to compare the potential analgesic effect of dexmedetomidine after intrathecal versus intra-articular administration following arthroscopic knee surgery. METHODS: Ninety patients undergoing unilateral elective arthroscopic knee surgery were randomly assigned into three groups in a double-blind placebo controlled study. The intrathecal dexmedetomidine group (IT) received an intrathecal block with intrathecal dexmedetomidine, the intra-articular group (IA) received an intrathecal block and intra-articular dexmedetomidine, and the control group received an intrathecal block and intra-articular saline. The primary outcome of our study was postoperative pain as assessed by the visual analogue scale of pain (VAS). Secondary outcomes included the effect of dexmedetomidine on total postoperative analgesic use and time to the first analgesic request, hemodynamics, sedation, postoperative nausea and vomiting, patient satisfaction, and postoperative C-reactive protein (CRP) levels. RESULTS: Dexmedetomidine administration decreased pain scores for 4 h in both the intrathecal and intra-articular groups, compared to only 2 h in the control patient group. Furthermore, there was a significant reduction in pain scores for 6 h in the intra-articular group. The time to the first postoperative analgesia request was longer in the intra-articular group compared to the intrathecal and control groups. The total meperidine requirement was significantly lower in the intra-articular and intrathecal groups than in the control group. CONCLUSIONS: Both intrathecal and intra-articular dexmedetomidine enhanced postoperative analgesia after arthroscopic knee surgery. Less total meperidine was required with intra-articular administration to extend postoperative analgesia to 6 h with hemodynamic stability.

10.
The Korean Journal of Pain ; : 134-141, 2017.
Article in English | WPRIM (Western Pacific) | ID: wpr-192933

ABSTRACT

BACKGROUND: Postoperative pain is a common, distressing symptom following arthroscopic knee surgery. The aim of this study was to compare the potential analgesic effect of dexmedetomidine after intrathecal versus intra-articular administration following arthroscopic knee surgery. METHODS: Ninety patients undergoing unilateral elective arthroscopic knee surgery were randomly assigned into three groups in a double-blind placebo controlled study. The intrathecal dexmedetomidine group (IT) received an intrathecal block with intrathecal dexmedetomidine, the intra-articular group (IA) received an intrathecal block and intra-articular dexmedetomidine, and the control group received an intrathecal block and intra-articular saline. The primary outcome of our study was postoperative pain as assessed by the visual analogue scale of pain (VAS). Secondary outcomes included the effect of dexmedetomidine on total postoperative analgesic use and time to the first analgesic request, hemodynamics, sedation, postoperative nausea and vomiting, patient satisfaction, and postoperative C-reactive protein (CRP) levels. RESULTS: Dexmedetomidine administration decreased pain scores for 4 h in both the intrathecal and intra-articular groups, compared to only 2 h in the control patient group. Furthermore, there was a significant reduction in pain scores for 6 h in the intra-articular group. The time to the first postoperative analgesia request was longer in the intra-articular group compared to the intrathecal and control groups. The total meperidine requirement was significantly lower in the intra-articular and intrathecal groups than in the control group. CONCLUSIONS: Both intrathecal and intra-articular dexmedetomidine enhanced postoperative analgesia after arthroscopic knee surgery. Less total meperidine was required with intra-articular administration to extend postoperative analgesia to 6 h with hemodynamic stability.


Subject(s)
Humans , Analgesia , Arthroscopy , Bupivacaine , C-Reactive Protein , Dexmedetomidine , Hemodynamics , Knee , Meperidine , Pain, Postoperative , Patient Satisfaction , Postoperative Nausea and Vomiting
11.
Exp Biol Med (Maywood) ; 239(7): 853-861, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24879424

ABSTRACT

Cancer chemotherapy is typically toxic. This problem could be addressed by using differences between cancer and normal cells for controlled delivery of drugs to cancer cells. One such difference is the ubiquitously elevated glutathione expression in cancer cells. We report a simple and versatile synthesis of water-soluble gold nanoparticles passivated with amine-containing molecules, which allow for controlled drug release via ligand exchange with bio-available glutathione. Taking methotrexate-passivated gold nanoparticles (Au:MTX) as an example, drug delivery and controlled release via glutathione-mediated ligand exchange was evaluated. Furthermore, the possibility of using Au:MTX to improve therapeutic index in acute myeloid leukemia (AML) models was examined in vitro and in vivo. Au:MTX exhibited cancer selectivity in vitro. Au:MTX had an elevated potency toward an AML cell line THP-1 in a dosage range of 1-5 nM, and therefore an enhanced delivery of drug, whereas normal hematopoietic stem/progenitor cell (HSPC) growth was minimally affected by Au:MTX and MTX treatments within the same range of dosage. In vivo efficacy and safety of Au:MTX was evaluated in a murine xenotransplant model of primary human AML. Au:MTX treatment, compared to control groups including MTX-only and Au nanoparticle-only treatments, produced better leukemia suppression without added toxicity, indicating an enhanced therapeutic index.

12.
J Biol Chem ; 289(21): 14881-95, 2014 May 23.
Article in English | MEDLINE | ID: mdl-24695740

ABSTRACT

Gene activation requires cooperative assembly of multiprotein transcription factor-coregulator complexes. Disruption to cooperative assemblage could underlie repression of tumor suppressor genes in leukemia cells. Mechanisms of cooperation and its disruption were therefore examined for PU.1 and RUNX1, transcription factors that cooperate to activate hematopoietic differentiation genes. PU.1 is highly expressed in leukemia cells, whereas RUNX1 is frequently inactivated by mutation or translocation. Thus, coregulator interactions of Pu.1 were examined by immunoprecipitation coupled with tandem mass spectrometry/Western blot in wild-type and Runx1-deficient hematopoietic cells. In wild-type cells, the NuAT and Baf families of coactivators coimmunoprecipitated with Pu.1. Runx1 deficiency produced a striking switch to Pu.1 interaction with the Dnmt1, Sin3A, Nurd, CoRest, and B-Wich corepressor families. Corepressors of the Polycomb family, which are frequently inactivated by mutation or deletion in myeloid leukemia, did not interact with Pu.1. The most significant gene ontology association of Runx1-Pu.1 co-bound genes was with macrophages, therefore, functional consequences of altered corepressor/coactivator exchange were examined at Mcsfr, a key macrophage differentiation gene. In chromatin immunoprecipitation analyses, high level Pu.1 binding to the Mcsfr promoter was not decreased by Runx1 deficiency. However, the Pu.1-driven shift from histone repression to activation marks at this locus, and terminal macrophage differentiation, were substantially diminished. DNMT1 inhibition, but not Polycomb inhibition, in RUNX1-translocated leukemia cells induced terminal differentiation. Thus, RUNX1 and PU.1 cooperate to exchange corepressors for coactivators, and the specific corepressors recruited to PU.1 as a consequence of RUNX1 deficiency could be rational targets for leukemia differentiation therapy.


Subject(s)
Cell Differentiation/genetics , Co-Repressor Proteins/genetics , Core Binding Factor Alpha 2 Subunit/genetics , Proto-Oncogene Proteins/genetics , Trans-Activators/genetics , Animals , Blotting, Western , Cells, Cultured , Chromatin Immunoprecipitation , Co-Repressor Proteins/metabolism , Core Binding Factor Alpha 2 Subunit/metabolism , Gene Expression Profiling , HEK293 Cells , Humans , Leukemia/genetics , Leukemia/metabolism , Leukemia/pathology , Macrophages/metabolism , Mice , Mice, Knockout , Mutation , Oligonucleotide Array Sequence Analysis , Protein Binding , Proto-Oncogene Proteins/metabolism , Tandem Mass Spectrometry , Trans-Activators/metabolism , Tumor Cells, Cultured
13.
Clin Lymphoma Myeloma Leuk ; 14(2): 172-177.e1, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24332215

ABSTRACT

BACKGROUND: Myelodysplastic syndrome (MDS) continues to cause major morbidity and mortality; thus, novel treatments are needed. The mammalian target of rapamycin (mTOR) inhibitor RAD001 (everolimus) inhibits cellular pathways important to MYC protein stability and cell growth. Pharmacodynamic biomarkers could be useful in distinguishing between (1) disease resistance that occurs even though mTOR is successfully inhibited (suggesting a need for a different treatment strategy) and (2) resistance that might respond to changes in drug dosage or schedule. PATIENTS AND METHODS: This was a small phase II trial of RAD001 in patients with low- and intermediate-1-risk MDS (n = 7). Protein S6K1 (S6) is downstream of mTOR, whereas protein kinase B (AKT) is upstream of mTOR. Therefore, to evaluate the pharmacodynamic effects of RAD001, S6 and AKT phosphorylation (pS6, pAKT) were measured by peripheral blood flow cytometry. RESULTS: Sequential weeks of RAD001 produced a decrease in pS6, whereas pAKT was maintained or increased. There were no clinical responses despite the biomarker evidence of intended pharmacodynamic effect. CONCLUSION: The pS6:pAKT ratio could be useful as a biomarker of target inhibition by RAD001 (clinicaltrials.gov identifier: NCT00809185).


Subject(s)
Biomarkers/metabolism , Myelodysplastic Syndromes/drug therapy , Proto-Oncogene Proteins c-akt/metabolism , Ribosomal Protein S6 Kinases/metabolism , Sirolimus/analogs & derivatives , Aged , Aged, 80 and over , Cell Line, Tumor , Drug Administration Schedule , Dyspnea/chemically induced , Everolimus , Fatigue/chemically induced , Female , Fever/chemically induced , Flow Cytometry , Humans , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Male , Middle Aged , Myelodysplastic Syndromes/metabolism , Neutropenia/chemically induced , Phosphorylation/drug effects , Sirolimus/adverse effects , Sirolimus/pharmacology , Sirolimus/therapeutic use , TOR Serine-Threonine Kinases/metabolism , Treatment Outcome
15.
Clin Cancer Res ; 19(4): 938-48, 2013 Feb 15.
Article in English | MEDLINE | ID: mdl-23287564

ABSTRACT

PURPOSE: The cytidine analogs 5-azacytidine and decitabine, used to treat myelodysplastic syndromes (MDS), produce a molecular epigenetic effect, depletion of DNA-methyltransferase 1 (DNMT1). This action is S-phase dependent. Hence, genetic factors that decrease the half-lives of these drugs could impact efficacy. Documentation of such impact, and elucidation of underlying mechanisms, could lead to improved clinical application. EXPERIMENTAL DESIGN: Cytidine deaminase (CDA) rapidly inactivates 5-azacytidine/decitabine. The effect of CDA SNP A79C and gender on CDA expression, enzyme activity, and drug pharmacokinetics/pharmacodynamics was examined in mice and humans, and the impact on overall survival (OS) was evaluated in 5-azacytidine/decitabine-treated patients with MDS (n = 90) and cytarabine-treated patients with acute myeloid leukemia (AML) (n = 76). RESULTS: By high-performance liquid chromatography (HPLC), plasma CDA activity was decreased as expected in individuals with the SNP A79C. Interestingly and significantly, there was an even larger decrease in females than in males. Explaining this decrease, liver CDA expression was significantly lower in female versus male mice. As expected, decitabine plasma levels, measured by mass spectrometry, were significantly higher in females. In mathematical modeling, the detrimental impact of shorter drug half-life (e.g., in males) was greater in low compared with high S-phase fraction disease (e.g., MDS vs. AML), because in high S-phase fraction disease, even a short exposure treats a major portion of cells. Accordingly, in multivariate analysis, OS was significantly worse in male versus female patients with MDS treated with 5-azacytidine/decitabine. CONCLUSIONS: Increased CDA expression/activity in males contributes to decreased cytidine analog half-life and likely contributes to worse outcomes with 5-azacytidine or decitabine therapy.


Subject(s)
Cytidine Deaminase/genetics , DNA (Cytosine-5-)-Methyltransferases/genetics , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Myelodysplastic Syndromes/drug therapy , Animals , Azacitidine/analogs & derivatives , Cytarabine/administration & dosage , Cytidine/administration & dosage , Cytidine/analogs & derivatives , Cytidine Deaminase/metabolism , DNA (Cytosine-5-)-Methyltransferase 1 , DNA (Cytosine-5-)-Methyltransferases/metabolism , Decitabine , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Leukemia, Myeloid, Acute/pathology , Male , Mice , Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/pathology , Polymorphism, Single Nucleotide , Survival Analysis , Treatment Outcome
16.
Oncotarget ; 3(10): 1137-45, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23087155

ABSTRACT

We document for the first time that sanctuary in an organ which expresses high levels of the enzyme cytidine deaminase (CDA) is a mechanism of cancer cell resistance to cytidine analogues. This mechanism could explain why historically, cytidine analogues have not been successful chemotherapeutics against hepatotropic cancers, despite efficacy in vitro. Importantly, this mechanism of resistance can be readily reversed, without increasing toxicity to sensitive organs, by combining a cytidine analogue with an inhibitor of cytidine deaminase (tetrahydrouridine). Specifically, CDA rapidly metabolizes cytidine analogues into inactive uridine counterparts. Hence, to determine if sheltering/protection of cancer cells in organs which express high levels of CDA (e.g., liver) is a mechanism of resistance, we utilized a murine xenotransplant model of myeloid cancer that is sensitive to epigenetic therapeutic effects of the cytidine analogue decitabine in vitro and hepato-tropic in vivo. Treatment of tumor-bearing mice with decitabine (subcutaneous 0.2mg/kg 2X/week) doubled median survival and significantly decreased extra-hepatic tumor burden, but hepatic tumor burden remained substantial, to which the animals eventually succumbed. Combining a clinically-relevant inhibitor of CDA (tetrahydrouridine) with a lower dose of decitabine (subcutaneous 0.1mg/kg 2X/week) markedly decreased liver tumor burden without blood count or bone marrow evidence of myelotoxicity, and with further improvement in survival. In conclusion, sanctuary in a CDA-rich organ is a mechanism by which otherwise susceptible cancer cells can resist the effects of decitabine epigenetic therapy. This protection can be reversed without increasing myelotoxicity by combining tetrahydrouridine with a lower dose of decitabine.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Azacitidine/analogs & derivatives , Cytidine Deaminase/metabolism , Leukemia, Myeloid/enzymology , Liver Neoplasms/enzymology , Liver/enzymology , Animals , Antimetabolites/therapeutic use , Antineoplastic Combined Chemotherapy Protocols , Azacitidine/therapeutic use , Decitabine , Humans , Leukemia, Myeloid/drug therapy , Leukemia, Myeloid/pathology , Liver/drug effects , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Mice , Mice, Knockout , Tetrahydrouridine/therapeutic use , Transplantation, Heterologous , Tumor Cells, Cultured , Tumor Suppressor Protein p53/physiology
17.
Syst Biol Reprod Med ; 58(5): 236-44, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22632096

ABSTRACT

We explored the relationship between sperm chromatin integrity, hormone levels, seminal plasma total antioxidant capacity (TAC), and routine sperm parameters in men with male factor (MF, n = 81) and non-male factor (NMF, n = 52) infertility. Semen and blood were collected and examined from men undergoing evaluation for infertility in the Avicenna Infertility Clinic. We have examined each patient for serum hormones (LH, FSH, E2, DHEA), sperm chromatin damage, level of protamination and seminal plasma TAC. Levels of FSH, LH, sperm chromatin damage, and abnormal protamination were significantly higher in MF vs. NMF groups (p < 0.001). Sperm chromatin damage was correlated with percentage of CMA(3)- positive sperm (r = 0.64, p < 0.001) and with sperm concentration (r = -0.36, p < 0.001), motility (r = -0.21, p < 0.05), and morphologically normal spermatozoa (r = -0.29, p < 0.001). Linear regression showed sperm chromatin damage was related to percentage of CMA(3)- positive sperm (p < 0.001) in ungrouped patients. It was related to both percentage of CMA(3)- positive sperm and serum DHEA in the MF group (p < 0.001 and p < 0.05, respectively). Sperm chromatin maturity assessed by CMA(3) test was inversely related to sperm chromatin damage assessed by the toludine blue assay. Male factor infertility associated with sperm chromatin damage may be related to sperm protamination and to serum DHEA.


Subject(s)
Antioxidants/analysis , Chromatin Assembly and Disassembly , Hormones/blood , Infertility, Male/diagnosis , Semen/chemistry , Spermatozoa/metabolism , Adolescent , Adult , Biomarkers/blood , Dehydroepiandrosterone/blood , Estradiol/blood , Follicle Stimulating Hormone, Human/blood , Humans , Infertility, Male/blood , Infertility, Male/genetics , Infertility, Male/pathology , Iran , Linear Models , Luteinizing Hormone/blood , Male , Middle Aged , Multivariate Analysis , Semen Analysis , Spermatozoa/pathology , Testosterone/blood , Young Adult
18.
J Androl ; 31(5): 482-8, 2010.
Article in English | MEDLINE | ID: mdl-20467051

ABSTRACT

The objective of this study was to elucidate the missense Glu298Asp polymorphism within exon 7 of the endothelial nitric oxide synthase (eNOS) gene in infertile men with asthenozoospermia and its potential role in sperm motility. In this prospective controlled study conducted in our andrology unit, we investigated the frequency of the 894G>T polymorphism (Glu298Asp variant) within exon 7 of the eNOS gene in 70 infertile men and 60 healthy men. Sperm motion kinetics were assessed with computer-assisted semen analysis. The presence of G>T, a single nucleotide polymorphism (SNP) in exon 7 of the eNOS gene (NCBI SNP cluster rs1799983; GenBank accession number NG_011992; protein accession number NP_000594) was determined by allelespecific polymerase chain reaction followed by restriction fragment length polymorphism analysis. Sequencing analysis was used to confirm the specific genotype. The 894G>T eNOS allele (T) was found at a higher frequency in the patients with asthenozoospermia (60% vs 22.5% in the control group; P = .02). The percentage of progressive motile sperm (grade a + b) was lower in the asthenozoospermic infertile men with the homozygous eNOS (TT) genotype than in the wild-type eNOS (GG) (P = .02) and heterozygous eNOS (GT) genotypes (P = .01). However, the percentage of progressive motile sperm (grade a + b) was higher in the wild-type vs mutant eNOS (TT) (P = .03) and heterozygous eNOS (GT) genotypes (P = .04). Our findings suggest that the T allele encoding for aspartic acid of the eNOS (Glu298Asp) gene may contribute to poor sperm motility.


Subject(s)
Asthenozoospermia/genetics , Nitric Oxide Synthase Type III/genetics , Polymorphism, Single Nucleotide , Asthenozoospermia/enzymology , Humans , Male , Prospective Studies , Sperm Motility/genetics
19.
Fertil Steril ; 94(6): 2482-5, 2485.e1-2, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20416871

ABSTRACT

In azoospermic infertile men with varicocele, testicular biopsy revealed histopathologic patterns that varied from disorganized spermatogenesis with low or moderate sperm scores to early (primary spermatocytes stage) or late (spermatid stage) arrested spermatogenesis or germ cell aplasia and Sertoli cells only. Diagnostic testicular biopsy can be helpful for accurate management of azoospermic infertile men with varicoceles before surgical repair.


Subject(s)
Azoospermia/pathology , Testis/pathology , Varicocele/pathology , Adult , Azoospermia/blood , Azoospermia/complications , Biopsy , Follicle Stimulating Hormone/blood , Humans , Infertility, Male/blood , Infertility, Male/etiology , Infertility, Male/pathology , Male , Organ Size , Sertoli Cells/pathology , Sperm Motility , Spermatogenesis/physiology , Spermatozoa/pathology , Varicocele/blood , Varicocele/complications
20.
Fertil Steril ; 94(6): 2037-42, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20138266

ABSTRACT

OBJECTIVE: To examine the relationship of early human embryonic development parameters to day 3 reactive oxygen species (D-3 ROS) levels in culture media. DESIGN: Prospective study. SETTING: Tertiary care hospital. PATIENT(S): Patients were undergoing IVF (n=92; 36 with intracytoplasmic sperm injection [ICSI]). INTERVENTION(S): The D-3 ROS levels in sample and control of each embryo culture dish were measured by the chemiluminescence method using a luminol probe. MAIN OUTCOME MEASURE(S): Embryo quality (days 3 and 5) and pregnancy rates (PR). RESULT(S): The D-3 ROS level was significantly lower in pregnant cycles 26.8±13.9×10(6) cpm (counted photon per minute) versus nonpregnant cycles 66.4±39.4×10(6) cpm. This relationship was maintained when the cycles were stratified to conventional IVF (27.1±14.95 vs. 67.0±39.9×10(6) cpm) or ICSI (25.6±12.75 vs. 65.5±39.7×10(6) cpm). After controlling for all variables, D-3 ROS levels were negatively correlated with blastocyst development rate as well as PR. Odds ratio (OR) (95% confidence interval [CI]) of clinical pregnancy corresponding to a 10×10(6) cpm increase in D-3 ROS was 0.47 (0.30-0.74) for ICSI and 0.56 (0.37-0.85) for IVF. CONCLUSION(S): During extended in vitro culture, ROS generated in culture media by day 3 may be an important biochemical marker for blastulation. An increase of 10 units in D-3 ROS may decrease the clinical pregnancy by 41%.


Subject(s)
Culture Media/chemistry , Fertilization in Vitro , Reactive Oxygen Species/analysis , Sperm Injections, Intracytoplasmic , Adult , Blastocyst/cytology , Blastocyst/metabolism , Cells, Cultured , Culture Media/metabolism , Embryo Culture Techniques , Female , Fertilization in Vitro/statistics & numerical data , Humans , Male , Pregnancy , Pregnancy Rate , Reactive Oxygen Species/metabolism , Sperm Injections, Intracytoplasmic/statistics & numerical data , Time Factors , Treatment Outcome
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