Halil Ates

Treatment of K562 cells with 1,25-dihydroxyvitamin D3 induces distinct alterations in the expression of apoptosis-related genes BCL2, BAX, BCLXL, and p21.

Apoptosis, or programmed cell death, is a very important phenomenon in cytotoxicity induced by anticancer treatment. 1α,25-Dihydroxyvitamin D3 (1,25-(OH)2D3), the active metabolite of vitamin D, inhibits the growth of multiple types of cancer cells including breast, colon, and prostate cancer cell lines. We studied alterations in the mRNA expression levels of BCL2, BAX, CYC, BCL-XL, and VDR genes in the K562 chronic myeloid leukemia cell line in response to treatment with 1,25-(OH)2D3. Morphological observation of K562 cells was evaluated by the staining with Wrights solution. Cell percentage at different phases of the cell cycle was measured, and apoptosis was measured by flow cytometry. The expression levels of the apoptosis-related genes were analyzed by real-time reverse transcription polymerase chain reaction. We found that treatment with 1,25-(OH)2D3 down-regulates BCL2 and BCL-XL mRNA expressions, as well as up-regulates expressions of BAX and p21 mRNA. The expression pattern of CYC and VDR genes were not influenced. However, K562 cells treated with 1,25-(OH)2D3 caused an arrest of cell cycle progression in G1 phase resulting in a decreased number of cells in the S phase, complemented by an accumulation of cells in the G0–G1 phases. Our data show the modulatory effects of 1,25-(OH)2D3 treatment in apoptosis-related genes in K562 cells.

Circulated Activated Platelets and Increased Platelet Reactivity in Patients With Behçet’s Disease:

Behçet’s disease (BD) is a multisystem disorder. Venous as well as arterial thrombosis is a common complication of BD but exact pathogenetic mechanism of the thrombotic tendency is not well known. This study aimed to evaluate circulating activated platelets and platelet reactivity in Behçet’s patients. Twenty-two Behçet’s patients (4 female, 18 male; mean age 38.6 ± 10.9 years) and 20 control subjects (8 female, 12 male; mean age 38.8 ± 9.4 years) were included. Those patients who had hypertension, hyperlipidemia, peripheral or coronary artery disease, hepatic or renal function abnormality, and who were using aspirin and other platelet-active drugs were excluded. Platelet activity and reactivity to adenosine diphosphate (ADP) were measured by whole blood flow cytometry. We assessed markers of platelet degranulation (P-selectin; CD62P) and the activated glycoprotein IIb/IIIa receptor (PAC1 binding to fibrinogen binding site) before and after stimulation with ADP. Platelet P-selectin expression was not significantly different between patients and control subjects both at baseline (p=0.420) and after stimulation (p=0.56). Baseline (p=0.001) and ADP-stimulated (p=0.003) PAC1 binding was significantly higher in Behçet’s patients than in the control group. Clinical activity has no effect on P-selectin expression and PAC1 binding. There is evidence of platelet activity and hyperreactivity in patients with BD and this may contribute to a prothrombotic state. In addition to aspirin, other antiplatelet drugs may be useful in the prevention and treatment of thrombosis in Behçet’s patients.

Reticulated platelet levels in patients with ulcerative colitis

Background and aimsIn this study, we investigated whether reticulated platelets (RP) would be useful markers in the evaluation of ulcerative colitis (UC) activity and also aimed to gain indirect information about the platelet kinetics.Materials and methodsComplete blood count, C-reactive protein, erythrocyte sedimentation rate, and proportion of RP were measured in 16 active, 21 inactive UC patients, and 20 healthy blood donors. UC activity was assessed by Truelove–Witts criteria.ResultsMean platelet count was increased in patients with active compared to inactive UC (p = 0.008) or healthy donors (p = 0.000). Mean platelet volume (MPV) was significantly decreased in patients with active compared to inactive (p = 0.015) and healthy donors (p = 0.001). RP values was significantly decreased in active and inactive UC groups compared to healthy donors (p = 0.000, p = 0.000, respectively), while there was no significant difference between active and inactive UC patients (p = 0.980). Significant negative correlation between platelet count and MPV in patients with active UC (r = −0.542, p = 0.030) was observed.ConclusionsRP values is reduced in active and inactive UC patients compared to healthy donors. To our knowledge, this is the first study about proportion of RP with UC in literature. However, the role of low RP values have not been determined clinically. Further studies are needed to evaluate the role of platelet abnormalities and changes in megakaryopoiesis caused by inflammatory state on low MPV and RP values during the course of UC.

Interferon gamma and lipopolysaccharide upregulate TNF-related apoptosis-inducing ligand expression in murine microglia.

In this study, it is reported that neonatal murine microglia and N9 murine microglial cell line express tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL). TRAIL protein and mRNA expression in murine microglia greatly upregulate upon stimulation with interferon gamma (IFNgamma) or lipopolysaccharide (LPS) as revealed by immunoprecipitation-immunoblotting, reverse transcriptase-polymerase chain reaction (RT-PCR) and flow cytometry techniques. IFNgamma and LPS act synergistically to induce TRAIL expression on both translational and transcriptional levels. The upregulated microglial TRAIL in inflammatory conditions may involve in the cytotoxic effect of these cells and play a role in neurodegenerative processes.

Investigation of megakaryocyte apoptosis in children with acute and chronic idiopathic thrombocytopenic purpura.

Abstract: Objective: Although the platelet destruction shows a primary role in the thrombocytopenia of idiopathic thrombocytopenic purpura (ITP), it has been demonstrated that impaired platelet production may also contribute to the severity of thrombocytopenia in ITP. The present study examined megakaryocyte apoptosis in bone marrow aspirates of children with acute and chronic ITP and investigated the role of megakaryocyte apoptosis in ITP pathophysiology.

Gingival involvement in a patient with CD56+ chronic myelomonocytic leukemia

Leukemic infiltration of the gingiva is most commonly reported to be associated with monocytic subtypes of acute myeloblastic leukemia (AML) but rarely with myelodysplastic syndromes (MDS). Here we report a case of CD56 +  chronic myelomonocytic leukemia (CMML) who developed gingival involvement simultaneously when the leukocyte count elevated. At that time no increase in peripheral or bone marrow blasts were observed. Gingival hypertrophy regressed with the treatment of hydroxyurea. Three months later, bone marrow blast count elevated and the patient was treated with two courses of AML-like regimen and then one course of consolidation therapy. The patient is in complete hematological remission for one and a half years. Similar to other extramedullary involvements, gingival hypertrophy in CMML can be a harbinger of the disease entering a more aggressive phase requiring systemic chemotherapy.

Zinc supplementation induces apoptosis and enhances antitumor efficacy of docetaxel in non-small-cell lung cancer

Background Exposure to exogenous zinc results in increased apoptosis, growth inhibition, and altered oxidative stress in cancer cells. Previous studies also suggested that zinc sensitizes some cancer cells to cytotoxic agents depending on the p53 status. Therefore, zinc supplementation may show anticancer efficacy solely and may increase docetaxel-induced cytotoxicity in non-small-cell lung cancer cells. Methods Here, we report the effects of several concentrations of zinc combined with docetaxel on p53-wild-type (A549) and p53-null (H1299) cells. We evaluated cellular viability, apoptosis, and cell cycle progression as well as oxidative stress parameters, including superoxide dismutase, glutathione peroxidase, and malondialdehyde levels. Results Zinc reduced the viability of A549 cells and increased the apoptotic response in both cell lines in a dose-dependent manner. Zinc also amplified the docetaxel effects and reduced its inhibitory concentration 50 (IC50) values. The superoxide dismutase levels increased in all treatment groups; however, glutathione peroxidase was slightly increased in the combination treatments. Zinc also caused malondialdehyde elevations at 50 μM and 100 μM. Conclusion Zinc has anticancer efficacy against non-small-cell lung cancer cells in the presence of functionally active p53 and enhances docetaxel efficacy in both p53-wild-type and p53-deficient cancer cells.

Evaluation of circulating endothelial and platelet microparticles in men with ankylosing spondylitis.

Objective. To evaluate the profiles of endothelial microparticles (EMP) and platelet microparticles (PMP) in men with ankylosing spondylitis (AS) and healthy subjects. We also aimed to determine whether microparticles (MP) correlate with disease activity, function, and spinal mobility indices. Methods. There were 82 men with AS and 53 healthy controls. Subjects with a history of chronic diseases including coronary artery disease, hypertension, diabetes mellitus, and dyslipidemia were excluded. MP were stained with monoclonal antibodies against platelets and endothelial cells and quantified using flow cytometry. MP that were positive for both CD42a+/CD31+ and total CD42a+ were identified as PMP; and MP consisting of CD42a–/CD31+ and total CD144+ were considered EMP. Results. EMP and PMP were similar between the patient and control groups (p > 0.05). Comparison of patients with AS in the active disease state (BASDAI ≥ 4) and in the inactive state showed that EMP and PMP were not different between the groups (p > 0.05). Correlation analysis revealed no correlation with Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, or Bath Ankylosing Spondylitis Metrology Index. C-reactive protein was significantly correlated with PMP and CD42a–/CD31+ EMP (p < 0.05). Comparison of patients with AS treated with anti-tumor necrosis factor (anti-TNF) drugs, subjects treated conventionally, and healthy controls revealed that PMP and CD42a–/CD31+ EMP were significantly downregulated in patients receiving biological agents. Conclusion. Circulating EMP and PMP, known to be indicators and mediators of vascular injury, were not significantly altered in men with AS who did not have classical cardiovascular risk factors. Significantly downregulated MP in patients receiving biological agents suggested that anti-TNF treatment may have a beneficial effect on vascular function in AS.

Neutrophil Apoptosis in Patients with β-Thalassemia Major

Increased susceptibility to infection is reported in patients with g -thalassemia major due to toxic effect of iron on neutrophil functions and reticuloendothelial system dysfunction. This study investigated the association between the neutrophil apoptosis and frequency of infection episodes, desferrioxamine treatment, and serum ferritin levels in patients with g -thalassemia major. A total of 35 children diagnosed with g -thalassemia major were enrolled. Group 1 consisted patients who were receiving desferrioxamine (DFO) and group 2 consisted of patients who did not start to receive DFO. A total of 15 healthy children were enrolled to serve as a control group. Frequency of infection episodes within a year was noted from hospital records. In all patients, the same method based on flow cytometry (annexin V labeled with FITC) was used to assess neutrophil apoptosis. Neutrophil count and percentage of apoptotic neutrophils did not differ significantly between the groups. When frequency of infection episodes among groups was evaluated, frequency of infection episodes of the patients who were receiving DFO was significantly higher than in the other groups. When correlation between neutrophil apoptosis and frequency of infection episodes, serum ferritin levels, and neutrophil count of the patients was analyzed according to groups, no significant correlation was found. The results indicate that high serum ferritin level and DFO use in patients with g -thalassemia major do not enhance neutrophil apotosis in vivo and enhanced neutrophil apoptosis cannot be a possible cause for increased susceptibility to infections in these patients.

TLR Polymorphisms in FMF: Association of TLR-2 (Arg753Gln) and TLR-4 (Asp299Gly, Thre399Ile) Polymorphisms and Myeloid Cell TLR-2 and TLR-4 Expression with the Development of Secondary Amyloidosis in FMF

Amyloidosis is the major complication of familial Mediterranean fever (FMF). Toll-like receptors (TLR) are involved in the activation of an innate immune system TLR-2 and TLR-4 recognize lipoteichoic acid and lipopolysaccharides (LPS), respectively. While TLR-2 Arg753Gln polymorphism upregulates, TLR-4 Asp299Gly and Thre399Ile polymorphisms downregulate inflammation. We investigated the effect of these polymorphisms on the development of amyloidosis in FMF patients. We also investigated myeloid cell TLR-2 and TLR-4 expressions in these patients. We studied 26 FMF patients and 13 FMF patients with amyloidosis. TLR-2 Arg753Gln and TLR-4 Asp299Gly and Thr399Ile polymorphisms were analyzed with the polymerase chain reaction-restriction fragment length polymorphism method. Myeloid cell baseline TLR-2 and TLR-4 and LPS-induced TLR-4 expressions were evaluated. The TLR-2 and TLR-4 polymorphism rate was compared with the results of 100 healthy subjects in our previous study. In addition, 13 healthy controls were enrolled for leukocyte TLR-2 and TLR-4 expressions. Serum amyloid A (SAA) levels were measured in these 13 control cases and in FMF patients during attack-free periods. The frequency of TLR-2 Arg753Gln, TLR-4 Asp299Gly, and Thr399Ile polymorphisms in healthy controls in our previous study were 1%, 3%, and 2%, respectively. The frequency of these polymorphisms were not different in FMF patients (with or without amyloidosis) compared to the control group. Likewise, myeloid cell TLR-2 and TLR-4 expressions were not different among the controls and FMF patients. However, LPS-induced TLR-4 expression in granulocytes was more prominent in FMF patients. There was no correlation between TLR-2 and TLR-4 expressions and SAA levels. Neither myeloid cell TLR-2 and TLR-4 expressions nor TLR-3 Arg753Gln, TLR-4 Asp299Gly, and Thr399Ile polymorphisms seem to affect the development of secondary amyloidosis in FMF patients in our study population.