ALBERT

Description: Introduction: T regulatory cells are immunosuppressive cells considered to play an important role in cancer biology and autoimmunity by suppressing host immune response and autoreactive lymphocytes respectively. Several studies reveal that Treg cells act by suppressing anti-tumor immune response, through the targeting of other immune cells, such as T cells, B cells and dendritic cells. Accumulated data indicate a significant role of T cell dysfunction in the pathogenesis of CLL. Aims: The scope of this study is the analysis of numerical and functional abnormalities of Tregs in B-CLL with the view to elucidate their role in the pathogenesis of the disease. Methods: Treg cells derived from 44 untreated B-CLL patients with a median age 62 and 17 healthy donors were analyzed by Flow cytometry, using the following antibodies: CD45Ro-FITC/CD45RA-PE/CD4-ECD/CD25-PC5/CD127-PC7, CD1a-FITC/CD137-PE/CD4-ECD/CD25-PC5/CD127-PC7, CD95-FITC/cyCD152-PE/CD4-ECD/CD25-PC5/CD127-PC7, beads/FoxP3-PE/CD4-ECD/CD25-PC5/CD127-PC7, Annexin V-FITC/CD4-ECD/CD25-PC5/CD127-PC7. For the functional analysis, peripheral blood was obtained from 20 patients with B-CLL. Mononuclear cells were isolated using Ficoll-Paque gradient centrifugation. CD4+ CD25+ (Treg cells), CD4+ CD25- (T effectοr cells, Teff), CD5+ CD19+ (B-CLL) and CD5- CD19+ (Normal B, NB) cells were separated using magnetic antibody cell sorting. To test the functionality of the assayed Tregs, the isolated cell populations were cultured in a 96-well plate (Tregs, Teff, B-CLL cells, NB cells, B-CLL cells: Tregs in 1:20 ratio, B-CLL cells: Teff in 1:20 ratio, NB cells: Tregs in 1:20 ratio, NB cells: Teff in 1:20 ratio) and their proliferative capacity was measured using the BrdU assay. To further analyze the functional role of Tregs, peripheral blood was obtained from 22 patients with CLL and 22 healthy donors. Mononuclear cells were isolated using Ficoll-Paque gradient centrifugation. CD4+ CD25+ CD127dim/- (Treg cells), CD5+ CD19+ (B-CLL) and CD5- CD19+ (Normal B, NB) cells were separated using magnetic antibody cell sorting and were co-cultured in a 96-well plate in a 1:10 ratio. The apoptosis of B cells was determined by the Annexin V/PI method. Results: FACS analysis of the Treg cells resulted at the following observations: The Treg absolute cell number (cells/μL), estimated either as the number of CD4+ CD25+ CD127- cells or as the number of CD4+ CD25+ FoxP3+ cells, was statistically significantly higher in patients' samples than in controls (CD127- 21.65 vs 7.35, p=0.001; FoxP3+ 20.42 vs 6.5, p= 0.001). Annexin V expression in Treg cells from BCLL patients was significantly lower compared to controls (3.626 vs 38.615, p=0.003). The functional analysis of Treg cells through BrdU assay indicated that CLL Tregs were able to suppress the proliferation of Teff cells (p=0.002) and that Teff cells were in turn able to significantly suppress the proliferation of B-CLL cells (p=0.05). Moreover, FACS analysis through Annexin V/PI method indicated that Treg CLL cells significantly decrease the apoptosis rate of NB cells after their co-culturing, compared to NB cells (p

Description: Introduction T regulatory cells are immunosuppressive cells, which are considered to play an important role in the regulation of immune response to cancer, by restraining autoreactive lymphocytes. Several studies, mostly in solid tumors, revealed that the number of Treg cells increases as the disease progresses and that Treg cells act by suppressing anti-tumor immune response, through the targeting of other immune cells, such as T cells, B cells and dendritic cells. Chronic lymphocytic leukemia (CLL) is a lymphoid malignancy, characterized by both, immunodeficiency and autoimmune disorders. Accumulated data indicate the role of T cells in the pathogenesis and development of CLL and reveal an increased number of Treg cells in CLL patients. The scope of this study is the analysis of the functional role of Tregs derived from the peripheral blood of CLL patients, mainly on B-CLL cells, and its correlation with well known prognostic factors. Methods Treg cells derived from mononuclear cells of 28 untreated B-cell CLL patients with a median age 62 (44-88) and 17 healthy donors were analyzed through Flow cytometry. Patients were classified according to Rai classification as Rai I:19, Rai II:4, Rai III:5 and according to Binet as Binet A: 24, Binet B:3 and Binet C:1. The following antibodies were used for the fluorescence-activated cell sorter (FACS) analysis: 1. CD45Ro-FITC/CD45RA-PE/CD4-ECD/CD25-PC5/CD127-PC7 2. CD1a-FITC/CD137-PE/CD4-ECD/CD25-PC5/CD127-PC7 3. CD95-FITC/cyCD152-PE/CD4-ECD/CD25-PC5/CD127-PC7 4. beads/FoxP3-PE/CD4-ECD/CD25-PC5/CD127-PC7 5. Annexin V-FITC/CD4-ECD/CD25-PC5/CD127-PC7 Moreover, peripheral blood was obtained from 15 patients with B-cell CLL. Mononuclear cells were isolated using Ficoll-Paque gradient centrifugation. CD4+CD25+ (Treg cells), CD4+CD25- (T effectοr cells, Teff), CD5+CD19+ (B-CLL) and CD5+CD19- (Normal B, NB) cells were separated using magnetic antibody cell sorting. To test the functionality of the assayed Tregs, the isolated cell populations were cultured in a 96-well plate (Tregs, Teff, B-CLL, NB cells, Tregs:Teff in a 4:1 ratio, B-cll:Tregs in 1:20 ratio, B-cll:Teff in 1:20 ratio, NB cells:Tregs in 1:20 ratio, NB cells:Teff in 1:20 ratio) and their proliferative capacity was measured using the BrdU assay. Results FACS analysis of the Treg cells resulted at the following observations: (1) The co-expression of the CD45RA-CD45RO markers was significantly higher in patients’ samples than in controls (p=0.047). (2) No significant differences were observed between patients and controls, regarding the expression of the CD1α marker, as well as the expression of CD95 and CD152 markers. (3) The Treg absolute cell number (cells/μL), estimated either as the number of CD4+ CD25+ CD127- cells or as the number of CD4+ CD25+ FoxP3+ cells, was statistically significantly higher in patients’ samples than in controls (CD127- p=0.047, FoxP3+ p= 0.036). (4) Annexin V expression in Treg cells from B- CLL patients was significantly lower compared to controls (p=0.027). Following the purification and culturing of T and B cells from B-cell CLL patients’ samples, functional analysis of the different cell populations was performed using the BrdU proliferation assay. We observed that Tregs were able to significantly suppress the proliferation of the Teff cells (p=0.002). After the co-culturing of NB cells (CD5+CD19-)and Tregs (CD4+CD25+) we found that NB cells seemed to significantly increase the proliferation of Treg cells, compared to the proliferation capacity of the Tregs when cultured alone (p=0.047). Moreover, we observed that Teff (CD4+CD25-) were able to significantly suppress the proliferation of B-CLL cells (CD5+CD19+), when co-cultured (B-CLL: Teff, 1:20 ratio) (p=0.05). Conclusions In B-cell CLL patients, Treg cells are significantly higher and present with lower apoptotic levels compared to healthy donors’ samples. The functional analysis of Treg cells indicates that they can effectively suppress the proliferation of T effector cells. Moreover, T effector cells seem to suppress the proliferation of B-CLL cells, while NB cells increase the proliferation of Treg cells. These observations could probably indicate that at the early stages of the disease, where NB cells are more aberrant, Treg cells’ activity is induced, leading to Teff cells’ suppression and therefore, to an indirect induction of B-CLL cells’ proliferation. Disclosures: No relevant conflicts of interest to declare.

Description: Introduction: Cutaneous T-cell lymphomas (CTCL) represent a heterogeneous group of extranodal non-Hodgkin lymphomas, derived from skin-homing mature T-cells. Mycosis fungoides (MF) and Sézary syndrome (SS) are the commonest types and together comprise 54% of all CTCL. MF evolves from patches to infiltrated plaques and eventually tumors. SS is a lymphoma-leukemia syndrome characterized by erythroderma and the presence of a malignant T-cell clone in the peripheral blood and the skin. At present, no curative treatment for CTCL is available. Therefore current CTCL research efforts are focused on elucidating the molecular mechanisms of the disease’s pathogenesis and on identifying new pharmacological targets. Several drugs have shown potentially significant activity either alone or in combination with conventional agents. Their effectiveness and their mechanisms of action comprise a current research challenge for the improvement of CTCL therapy. The aim of this study was to investigate the possible alterations in the gene expression profile (focusing on DNA Damage Signaling and DNA Repair pathways) and cell death in CTCL cell lines after treatment with two chemotherapeutic agents, Bortezomib and Methotrexate. Methods: Three CTCL cell lines were used. MyLa, (MF), SeAx and Hut-78 (both SS). Cells were cultured in RPMI 1640 and were treated with either Bortezomib (10nmol/L) or Methotrexate (10μM) for 24h. Apoptosis was determined by flow cytometry using the Annexin V/PI method. Gene expression profiling following PCR arrays analysis was performed after total RNA extraction and purification from untreated and drug-treated cells. All RNA samples’ amplification, labeling and hybridization to RT2 Profiler PCR Arrays (DNA Damage Signaling and DNA Repair PCR array) (QIAGEN) were performed according to the manufacturer’s instructions. All data were analyzed using the appropriate RT2 Profiler PCR Array data analysis tool. Results: Hut-78, Seax and Myla cells responded with statistically significant enhanced apoptosis when treated for 24h with bortezomib, compared to untreated cells, while Methotrexate led to a rather moderate increase of apoptosis in Hut-78 and Seax cells and did not affect the apoptosis of Myla cells. Microarrays analysis after bortezomib treatment revealed a great effect in the expression profile of genes involved in almost all DNA repair pathways tested, in all three cell lines, with Hut-78 being affected the most. Specifically, in all cell lines, there was a significant down-regulation of a large number of genes involved in the Double Strand Breaks DNA Repair mechanism, (i.e. BRCA1, BRCA2, RAD50, RAD51, RAD51C, XRCC2, XRCC3, XRCC4, XRCC5 and XRCC6) as well as of genes involved in the Mismatch Repair pathway (i.e. MLH1, MLH3, MSH2, MSH5, MSH6) and the Nucleotide Excision Repair mechanism (i.e. DDB2, LIG1 and RAD23A), compared to untreated cells. On the contrary, bortezomib had a small effect on Base Excision repair mechanism, mostly downregulating the expression of XRCC1 gene in Hut-78 and Myla cells. Methotrexate treatment also led to a significant down-regulation of genes involved in the DSB (RAD50, XRCC4, XRCC6), MMR (MSH4) and NER (CDK7, RAD23A) repair mechanisms in Hut-78 cells but had a rather much more moderate effect on the expression profile of Seax and Myla cells, where fewer genes were affected. Conclusions: Our data clearly demonstrate a differential effect of bortezomib and methotrexate in terms of apoptosis induction on CTCL cells with bortezomib inducing apoptosis of both MF and SS derived cell lines and methotrexate being rather inactive on SS derived cells. We showed that both drugs, but mostly bortezomib significantly down-regulate a large number of genes involved in the DSB, MMR and NER mechanisms, suggesting a possible mechanism, among probably others, for the enhanced sensitivity to apoptosis of SS and MF cell lines after treatment. Bortezomib’s significant effect could be easily understood, since it is a well known proteasome inhibitor and has been previously related to inhibition of NF-kB and accumulation of pro-apoptotic proteins, while it has also been reported that cancer cells are more sensitive to proteasome inhibition than normal cells. Although these results need to be further confirmed, they appear very encouraging for understanding the mechanisms of action of these drugs in CTCL with the view to ameliorate their use in clinical practice. Disclosures No relevant conflicts of interest to declare.

Description: The role of nutrition in the pathogenesis of cardiovascular disease has long been debated. The established notion of the deleterious effects of fat is recently under question, with numerous studies demonstrating the benefits of low-carbohydrate, high-fat diets in terms of obesity, diabetes, dyslipidemia, and metabolic derangement. Monounsaturated and polyunsaturated fatty acids, especially n-3 PUFAs (polyunsaturated fatty acids), are the types of fat that favor metabolic markers and are key components of the Mediterranean Diet, which is considered an ideal dietary pattern with great cardioprotective effects. Except for macronutrients, however, micronutrients like polyphenols, carotenoids, and vitamins act on molecular pathways that affect oxidative stress, endothelial function, and lipid and glucose homeostasis. In relation to these metabolic markers, the human gut microbiome is constantly revealed, with its composition being altered by even small dietary changes and different microbial populations being associated with adverse cardiovascular outcomes, thus becoming the target for potential new treatment interventions. This review aims to present the most recent data concerning different dietary patterns at both the macro- and micronutrient level and their association with atherosclerosis, obesity, and other risk factors for cardiovascular disease.

Description: The link between eating rate and energy intake has long been a matter of extensive research. A better understanding of the effect of food intake speed on body weight and glycemia in the long term could serve as a means to prevent weight gain and/or dysglycemia. Whether a fast eating rate plays an important role in increased energy intake and body weight depends on various factors related to the studied food such as texture, viscosity and taste, but seems to be also influenced by the habitual characteristics of the studied subjects as well. Hunger and satiety quantified via test meals in acute experiments with subsequent energy intake measurements and their association with anorexigenic and orexigenic regulating peptides provide further insight to the complicated pathogenesis of obesity. The present review examines data from the abundant literature on the subject of eating rate, and highlights the main findings in people with normal weight, obesity, and type 2 diabetes, with the aim of clarifying the association between rate of food intake and hunger, satiety, glycemia, and energy intake in the short and long term.

Description: Introduction: Cutaneous T-cell lymphomas (CTCL) represent a heterogeneous group of extranodal non-Hodgkin lymphomas, derived from skin-homing mature T-cells. The two most common types of CTCL are Mycosis fungoides (MF) (50%-72%), which is generally indolent in behavior, and Sézary syndrome (SS) (1%-3%), an aggressive leukemic form of the disease. Currently, there is no effective treatment for CTCL patients. Research on new therapies for CTCL is largely centered on defining novel therapeutic targets, but in most cases the response is short and the survival rate remains the same. Therefore, the CTCL's resistance to chemotherapy and the lack of full understanding of their pathogenesis request further investigation. Aims: With the view of a more targeted therapy, we evaluated in vitro the effectiveness of lenalidomide, an immunomodulatory agent (IMID) with clinical efficacy, among others, in plasma cell dysplasias and lymphoproliferative disorders. Methods: Four CTCL cell lines were used: MJ and MyLa (derived from MF), SeAx and Hut-78 (both derived from peripheral blood of patients with Sézary syndrome). SeAx and Hut-78 cells were cultured in RPMI 1640, supplemented with 10% FBS and 2 mM L-glutamine. MJ and MyLa cells were cultured in RPMI 1640 and IMDM, respectively, supplemented with 20% FBS. All cell lines were maintained at 37°C in a humid atmosphere of 5% CO2. Cells were treated with various concentrations of lenalidomide (1μΜ, 10μΜ and 100μΜ) for 24, 48 and 72h. Apoptosis was determined by flow cytometry using the Annexin V/PI method. The proliferative capacity of untreated and lenalidomide- treated cells was measured using the BrdU assay. One-way Anova and LSD/ Bonferroni methods were applied for the statistical analysis of the results. Results: Our data indicate that all cell lines responded with enhanced apoptosis at various lenalidomide treatment conditions. Between the two MF lines tested, MyLa cells were affected the most. Specifically, MyLa cells exhibited a statistically significant augmentation on their apoptosis compared to untreated cells after treatment with 10μΜ and 100μΜ lenalidomide for 24h (9.7 and 8.66 vs 4.83, p=0.000 and p

Description: INTRODUCTION AML is the most common malignant myeloid disorder in adults. Relapses are initiated by chemoresistant leukemic cells. DNA damage and repair mechanisms influence not only the genetic predisposition to leukemia but are also very important for refractoriness to treatment. The aim of this study was to investigate the possible alterations in the gene expression profile in DNA damage signaling pathways in two leukemic cell lines following their exposure to chemotherapeutic agents and verify the findings in AML patients. METHODS Kasumi-1 and MV4-11 AML cells were treated with either idarubicin (0.1μΜ) for 6h or cytarabine (1μΜ) for 48h. Dead cells were eliminated from drug-treated cells using the appropriate commercial kit. Gene expression profiling through PCR arrays analysis (RT2Profiler, Qiagen) was performed after RNA extraction from untreated, drug-treated and chemoresistant (live) cells following their exposure to cytotoxic agents. Human DNA Damage Signaling pathway related genes' expression was evaluated and analyzed through RT2Profiler PCR Array data analysis tool. Following our initial results, two genes were selected for further analysis: PPP1R15A and HUS-1 genes' relative expression was evaluated by qRT-PCR analysis with QuantiTect Primer Assays kit (Qiagen) using the 2^-∆∆Ct method. The analysis included 28 de novo AML patients before the onset of the 7+3 combination chemotherapy and 16 healthy donors. Eighteen cases had normal karyotype including 7 with flt3 mutation, 1 case had inv(16) and 9 cases intermediate risk karyotype. Statistics were performed through One Way Anova analysis. RESULTS PCR Array analysis after idarubicin and cytarabine treatment of Kasumi-1 cells revealed a significant up-regulation of genes involved in apoptosis, cell cycle, DNA damage and repair, and ATM/ATR signaling. Significant differences in their gene expression patterns were observed between cytarabine-treated Kasumi-1 cells and chemoresistant ones. HUS-1 gene (DSB) was 3x fold up-regulated in cytarabine-treated cells and 0.7x fold down-regulated in chemoresistant cells compared to untreated cells. Cytarabine and idarubicin treatment of MV4-11 cells led to an up-regulation of genes involved in cell cycle, DNA damage repair, including DSB repair and NER mechanisms. Most importantly, PPP1R15A gene's expression in both cytarabine and idarubicin chemoresistant MV4-11 cells was significantly 4.2x and 2.7x fold up-regulated compared to drug treated cells. Following these results the expression level of genes PPP1R15A and HUS1 was examined in the bone marrow cells of AML patients in order to verify their association with chemoresistance. PPP1R15A gene's relative expression was significantly up-regulated in non-responding to induction chemotherapy AML patients compared to responding (median: 2.705 vs. 0.73, p