The miRNA content of circulating exosomes in DLBCL patients and in vitro influence of DLBCL-derived exosomes on miRNA expression of healthy B-cells from peripheral blood.

BACKGROUND: Due to the heterogeneous nature of Diffuse Large B-cell Lymphoma (DLBCL), the mechanisms underlying tumor development and progression have not yet been fully elucidated. OBJECTIVE: This study aimed to compare the characteristics of plasma exosomes of DLBCL patients and healthy individuals and to evaluate the exosomal interactions between DLBCL cell lines and normal B-cells. METHODS: Exosome isolation was performed using an ultracentrifugation-based protocol from plasma of 20 patients with DLBCL and 20 controls. The expression of miRNAs from exosome samples was analyzed using a miRNA expression microarray. The presence of exosome-mediated communication between the lymphoma cells and normal B-cells was determined by the co-culture model. RESULTS: A significant increase in plasma exosome concentrations of DLBCL patients was observed. There was also a significant decrease in the expression of 33 miRNAs in plasma exosomes of DLBCL patients. It was determined that normal B-cells internalize DLBCL-derived exosomes and then miRNA expression differences observed in normal B-cells are specific to lymphoma-subtypes. CONCLUSIONS: MiR-3960, miR-6089 and miR-939-5p can be used as the miRNA signature in DLBCL diagnosis. We suppose that the exosomes changed the molecular signature of the target cells depending on the genomic characterization of the lymphoma cells they have originated.

Determination of the pathways of potential muscle damage and regeneration in response to acute and long-term swimming exercise in mice.

The objective of the current study was examining early and late (3, 24 h) responses to acute, chronic swimming exercise as muscle damage and regeneration in gastrocnemius-soleus muscle complexes. We also aimed to reveal the signaling pathways involved. 8-12 weeks old mice were grouped as control, exercise. Exercising groups were firstly divided into two as acute and chronic, later every group was again divided in terms of time (3, 24 h) passed from the last exercise session until exsanguination. Acute exercise groups swam 30 min, while chronic swimming groups exercised 30 min/day, 5 days/week, 6 weeks. Histological investigations were performed to determine muscle damage and regeneration. Whole-genome expression analysis was applied to total RNA samples. Microarray data was confirmed by quantitative real-time PCR. Exercising mice muscle revealed enhanced damage, leukocyte infiltration. Increments in acute and chronic 3 h groups were statistically significant. Car3, Neb, Obscn, Ttn, Igfbp5, Igfbp7, Gsk3ß, and Usp2 were down-regulated in muscles of swimming mice. The exercise-induced signaling pathways involved in muscle damage and regeneration were drawn. Our findings demonstrate that swimming induces muscle damage. Samples were obtained at 3 and 24 h following exercise, this time duration seems not sufficient for the development of myofibrillogenesis.

Contribution of Heme Oxygenase 2 to Blood Pressure Regulation in Response to Swimming Exercise and Detraining in Spontaneously Hypertensive Rats.

BACKGROUND We aimed to determine the effects of exercise followed by detraining on systolic blood pressure (SBP), heme oxygenase 2 (HO-2) expression, and carboxyhemoglobin (COHb) concentration in spontaneously hypertensive rats (SHR) to explain the role of carbon monoxide (CO) in this process. MATERIAL AND METHODS Animals were randomized into exercised and detrained groups. Corresponding sedentary rats were grouped as Time 1-2. Swimming of 60 min/5 days/week for 10 weeks was applied. Detraining rats discontinued training for an additional 5 weeks. Gene and protein expressions were determined by real-time PCR and immunohistochemistry. RESULTS Aorta HO-2 histological scores (HSCORE) of hypertensive rats were lower, while SBP was higher. Swimming caused enhancement of HO-2 immunostaining in aorta endothelium and adventitia of SHR. Exercise induced elevation of blood COHb index in SHR. Synchronous BP lowering effect of exercise was observed. HO-2 mRNA expression, HSCORE, and blood COHb index were unaltered during detraining, while SBP was still low in SHR. CONCLUSIONS CO synthesized by HO-2 at least partly plays a role in SBP regulation in the SHR- and BP-lowering effect of exercise. Regular exercise with short-term pauses may be advised to both hypertensives and individuals who are at risk.

Human TLR gene family members are differentially expressed in patients with urothelial carcinoma of the bladder.

PURPOSE: Toll-like receptors (TLRs) have an important role in the activation of both innate and adaptive immunity in response to pathogens and endogenous danger signals from damaged or dying cells. The aim of this study was to determine the relationship between urothelial carcinoma (UC) and TLR expression. BASIC PROCEDURES: Real-time polymerase chain reaction evaluation was made of the messenger RNA expression of TLRs 1-10 in 24 UC samples and 46 nontumoral bladder tissue samples. The levels of proinflammatory cytokines (IL-1ß, IL-6, and IL-8) in the urine samples were also determined with enzyme-linked immunosorbent assay. MAIN FINDINGS: TLR2-7 and TLR10 expressions were significantly higher in UC than in the control group (P<0.05 for all comparisons). No concordance was found between matched tumor tissue and urine samples in terms of TLR expression. IL-1ß, IL-6, and IL-8 levels were significantly higher in urine specimens of patients with UC (P = 0.033, P = 0.001, and P = 0.008, respectively). PRINCIPAL CONCLUSIONS: The results of this study demonstrated that the TLR gene expression profiles reflect the heterogeneity within UC. These results might also prompt further investigation to better understand the role of the TLR gene family expression in the tumor progression of UC.

MYD88 expression and L265P mutation in mature B-cell non-Hodgkin lymphomas.

BACKGROUND: Myeloid differentiation primary response 88 (MYD88) is a common adaptor protein that is responsible for signaling from several receptors; mutations in this gene may play a role in the pathogenesis of lymphoma. AIM: We aimed to determine the MYD88 L265P mutation frequency, the level of MYD88 expression, and their associations with clinicopathological parameters in mature B-cell non-Hodgkin lymphomas (NHLs). METHODS: A total of 68 patients were included in the study. The presence of the MYD88 L265P mutation was analyzed by real-time polymerase chain reaction and direct sequencing. MYD88 protein expression was evaluated by immunohistochemistry (IHC) using two different scoring systems. RESULTS: MYD88 L265P mutation was present in eight (18.6%) diffuse large B-cell lymphoma (DLBCL) patients. We also observed a significant association between the loss of MYD88 expression and advanced stage in both mature B-cell NHL and DLBCL according to the first IHC scoring systems (p=0.015 and p=0.024, respectively). An association was also seen between MYD88 overexpression and low clinical risk in both mature B-cell NHL and DLBCL according to the second IHC scoring system (p=0.027 and p=0.024, respectively). CONCLUSIONS: The L265P mutation may be helpful for understanding the pathogenesis of immune-privileged site-associated DLBCLs. The presence of the mutation, together with its protein overexpression, could also be used as a prognostic marker in advanced stage DLBCLs.

Possible Role of GADD45γ Methylation in Diffuse Large B-Cell Lymphoma: Does It Affect the Progression and Tissue Involvement?

OBJECTIVE: Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma among adults and is characterized by heterogeneous clinical, immunophenotypic, and genetic features. Different mechanisms deregulating cell cycle and apoptosis play a role in the pathogenesis of DLBCL. Growth arrest DNA damage-inducible 45 (GADD45γ) is an important gene family involved in these mechanisms. The aims of this study are to determine the frequency of GADD45γ methylation, to evaluate the correlation between GADD45γ methylation and protein expression, and to investigate the relation between methylation status and clinicopathologic parameters in DLBCL tissues and reactive lymphoid node tissues from patients with reactive lymphoid hyperplasia. MATERIALS AND METHODS: Thirty-six tissue samples of DLBCL and 40 nonmalignant reactive lymphoid node tissues were analyzed in this study. Methylation-sensitive high-resolution melting analysis was used for the determination of GADD45γ methylation status. The GADD45γ protein expression was determined by immunohistochemistry. RESULTS: GADD45γ methylation was frequent (50.0%) in DLBCL. It was also significantly higher in advanced-stage tumors compared with early-stage (p=0.041). In contrast, unmethylated GADD45γ was associated with nodal involvement as the primary anatomical site (p=0.040). CONCLUSION: The results of this study show that, in contrast to solid tumors, the frequency of GADD45γ methylation is higher and this epigenetic alteration of GADD45γ may be associated with progression in DLBCL. In addition, nodal involvement is more likely to be present in patients with unmethylated GADD45γ.