Czy leczenie inhibitorami DPP-4 ma wpływ na subpopulacje limfocytów u chorych na cukrzycę typu 2?

Introduction: Dipeptidil peptidase 4 inhibitors (DPP-4) are a group of antihyperglycemic agents. DPP-4 is an enzyme expressed on lymphocyte surface as co-stimulatory molecule in activation processes. The aim was to assess lymphocyte subpopulations initially and after 14 days of treatment with DPP-4 inhibitors sitagliptin, saxagliptin and vildagliptin.Material and methods: The study was conducted in three groups 10 subjects each, of type 2 diabetic patients. In subjects studied an initial tests followed by repeated ones after 14 days of treatment with sitagliptin, saxagliptin, and vildagliptin in therapeutic doses were performed. Baseline test as well as lymphocyte subpopulations (total T cells, and T-cell subsets CD4+, CD8+, CD26+, CD45RA+, CD45RO+, CD4+/CD25+) using 7-colour flow cytometry method were performed.Results: In patients receiving sitagliptin no significant increase in lymphocyte subpopulations were observed. In patients who received vildagliptin significant increase of total T-cells (p < 0.05); in patients treated with saxagliptin significant (p < 0.05) though mild increased percentage of total T-cells and CD4+, CD26+, CD45RO+ subsets were found.Conclusions: The study showed mild but significant increase of several T-cell subsets after treatment with saxagliptin and vildagliptin with non significant elevation after treatment with sitagliptin. It seems that changes are not expressed enough to have a clinical impact. (Endokrynol Pol 2014; 65 (2): 78–82)Wstęp: Inhibitory dipeptydylo peptydazy 4 (DPP-4) są nową grupą leków hipoglikemizujących. DPP-4 jest enzymem występującym między innymi na powierzchni limfocytów, molekułą ko-stymulującą w procesach aktywacji. Celem niniejszej pracy była ocena subpopulacji limfocytów przed i po 14-dniowym leczeniu inhibitorami DPP-4 sitagliptyną, saxagliptyną i vildagliptyną.Materiał i metody: Badanie przeprowadzono w trzech 10-osobowych grupach pacjentów z cukrzycą typu 2. U badanych wykonano badania wstępne, a następnie badania powtórzono po 14 dniach pobierania sita-, saxa- i vildagliptyny w dawkach terapeutycznych. U badanych wykonano badania podstawowe, a także oznaczono subpopulacje limfocytów (całkowite limfocyty T oraz subpopulacje limfocytów T CD4+, CD8+, CD26+, CD45RA+, CD45RO+, CD4+/CD25+; całkowite limfocyty B i subpopulacja CD26+) metodą 7-kolorowej cytometrii przepływowej.Wyniki: U badanych otrzymujących sitagliptynę nie obserwowano znamiennego wzrostu w zakresie badanych subpopulacji limfocytów. U chorych otrzymujących vildagliptynę obserwowano istotny (p < 0,05), choć niewielki wzrost całkowitej puli limfocytów. Pacjenci otrzymujący saxagliptynę wykazywali istotny (p < 0.05), choć niewielki wzrost odsetka limfocytów T całkowitych, TCD4, CD26+, CD45RO+.Wnioski: Badanie wskazuje na niewielki wzrost puli limfocytów T po zastosowaniu saxagliptyny i vildagliptyny, bez wpływu sitagliptyny. Wydaje się, ze stwierdzane zmiany, mimo że znamienne, są na tyle niewielkie, że nie powinny mieć znaczenia klinicznego. (Endokrynol Pol 2014; 65 (2): 78–82

hsa-miR-20b-5p and hsa-miR-363-3p affect expression of PTEN and BIM tumor suppressor genes and modulate survival of T-ALL cells in vitro

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy arising from T lymphocyte precursors. We have previously shown by miRNA-seq, that miRNAs from the mir-106a-363 cluster are overexpressed in pediatric T-ALL. In silico analysis indicated their potential involvement in the regulation of apoptosis. Here, we aimed to test the hypothesis on the pro-tumorigenic roles of these miRNAs in T-ALL cells in vitro. We demonstrate, for the first time, that hsa-miR-20b-5p and hsa-miR-363-3p from the mir-106a-363 cluster, when upregulated in T-ALL cells in vitro, protect leukemic cells from apoptosis, enhance proliferation, and contribute to growth advantage. We show, using dual luciferase reporter assays, Ago2-RNA immunoprecipitation, RT-qPCR, and Western blots, that the oncogenic effects of these upregulated miRNAs might, at least in part, be mediated by the downregulation of two important tumor suppressor genes, PTEN and BIM, targeted by both miRNAs. Additionally, we demonstrate the cooperative effects of these two miRNAs by simultaneous inhibition of both miRNAs as compared to the inhibition of single miRNAs. We postulate that hsa-miR-20b-5p and hsa-miR-363-3p from the mir-106a-363 cluster might serve as oncomiRs in T-ALL, by contributing to post-transcriptional repression of key tumor suppressors, PTEN and BIM

Association of germline genetic variants in RFC, IL15 and VDR genes with minimal residual disease in pediatric B-cell precursor ALL

Minimal residual disease (MRD) enables reliable assessment of risk in acute lymphoblastic leukemia (ALL). However, little is known on association between MRD status and germline genetic variation. We examined 159 Caucasian (Slavic) patients with pediatric ALL, treated according to ALL-IC-BFM 2002/2009 protocols, in search for association between 23 germline polymorphisms and MRD status at day 15, day 33 and week 12, with adjustment for MRD-associated clinical covariates. Three variants were significantly associated with MRD: rs1544410 in VDR (MRD-day15); rs1051266 in RFC (MRD-day33, MRD-week12), independently and in an additive effect with rs10519613 in IL15 (MRD-day33). The risk alleles for MRD-positivity were: A allele of VDR (OR = 2.37, 95%CI = 1.07–5.21, P = 0.03, MRD-day15); A of RFC (OR = 1.93, 95%CI = 1.05–3.52, P = 0.03, MRD-day33 and MRD-week12, P < 0.01); A of IL15 (OR = 2.30, 95%CI = 1.02–5.18, P = 0.04, MRD-day33). The risk for MRD-day33-positive status was higher in patients with risk alleles in both RFC and IL15 loci than in patients with risk alleles in one locus or no risk alleles: 2 vs. 1 (OR = 3.94, 95% CI = 1.28–12.11, P = 0.024), 2 vs. 0 (OR = 6.75, 95% CI = 1.61–28.39, P = 0.012). Germline variation in genes related to pharmacokinetics/pharmacodynamics of anti-leukemic drugs and to anti-tumor immunity of the host is associated with MRD status and might help improve risk assessment in ALL

Expression Patterns of Coagulation Factor XIII Subunit A on Leukemic Lymphoblasts Correlate with Clinical Outcome and Genetic Subtypes in Childhood B-cell Progenitor Acute Lymphoblastic Leukemia

L

An Extensive Quality Control and Quality Assurance (QC/QA) Program Significantly Improves Inter-Laboratory Concordance Rates of Flow-Cytometric Minimal Residual Disease Assessment in Acute Lymphoblastic Leukemia: An I-BFM-FLOW-Network Report

Monitoring of minimal residual disease (MRD) by flow cytometry (FCM) is a powerful prognostic tool for predicting outcomes in acute lymphoblastic leukemia (ALL). To apply FCM-MRD in large, collaborative trials, dedicated laboratory staff must be educated to concordantly high levels of expertise and their performance quality should be continuously monitored. We sought to install a unique and comprehensive training and quality control (QC) program involving a large number of reference laboratories within the international Berlin-Frankfurt-Münster (I-BFM) consortium, in order to complement the standardization of the methodology with an educational component and persistent quality control measures. Our QC and quality assurance (QA) program is based on four major cornerstones: (i) a twinning maturation program, (ii) obligatory participation in external QA programs (spiked sample send around, United Kingdom National External Quality Assessment Service (UK NEQAS)), (iii) regular participation in list-mode-data (LMD) file ring trials (FCM data file send arounds), and (iv) surveys of independent data derived from trial results. We demonstrate that the training of laboratories using experienced twinning partners, along with continuous educational feedback significantly improves the performance of laboratories in detecting and quantifying MRD in pediatric ALL patients. Overall, our extensive education and quality control program improved inter-laboratory concordance rates of FCM-MRD assessments and ultimately led to a very high conformity of risk estimates in independent patient cohorts

New research on saponins shows their wide range of pharmacological activities

Saponins (saponosides) belong to a group of secondary metabolites, widely distributed mainly, but not exclusively, among plants. They are reported to occur in over 500 species from over 90 families of both edible and nonedible plants. Chemically, saponins are glycosides consisting of a sugar moiety and non-sugar aglycone, called also sapogenin. Depending on the number of sugar chains attached to the aglycone, mono-, bi- and tridesmosides are distinguished. According to the structure of aglycone, saponins are classified into steroidal and triterpenoid. Common for all types of saponins are their surface-active properties and the ability to form a stable foam in water solutions. This property makes saponins applicable as components of household detergents and fire extinguishers. Saponins have a high ability to bind to cell membrane sterols, which is responsible at least in part for their biological activities. They reveal also strong haemolytic properties, which differ depending on the saponin type and its aglycone structure. Saponins exhibit a wide range of biological properties and are believed to be one of the key biologically active constituents of plant drugs used in folk, especially Far East medicine. Many of the most important saponins are present in the roots of ginseng (Panax ginseng), soybeans (Glycine max) and plants of Bupleurum genus. Saponins are also widely used in conventional medicine (i.e. expectorants, hypocholesterolemic drugs). Moreover many studies in vitro and in vivo exhibited their anti-inflammatory, antimutagenic, antiviral, antibacterial, antifungal, analgesic, and antitumour activities. The latter is the most promising because of its possible future therapeutical application, since many cancer cell lines are more vulnerable to saponins than normal cells. Its cytotoxicity in most cases is the result of apoptosis, nevertheless additional studies including determination of the inhibitory mechanisms of saponins should be addressed