Search

Pulsed electromagnetic fields (PEMFs) have been used to treat bone diseases, particularly nonunion healing. Although it is known that PEMFs promote the osteogenic differentiation of human mesenchymal stem cells (hMSCs), to date PEMF molecular mechanisms remain not clearly elucidated. The Notch signalling is a highly conserved pathway that regulates cell fate decisions and skeletal development. The aim of this study was to investigate if the known PEMF-induced osteogenic effects may involve the modulation of the Notch pathway. To this purpose, during in vitro osteogenic differentiation of bone marrow hMSCs in the absence and in the presence of PEMFs, osteogenic markers (alkaline phosphatase activity, osteocalcin and matrix mineralization), the messenger ribonucleic acid expression of osteogenic transcription factors (Runx2, Dlx5, Osterix) as well as of Notch receptors (Notch1-4), their ligands (Jagged1, Dll1 and Dll4) and nuclear target genes (Hes1, Hes5, Hey1, Hey2) were investigated. PEMFs stimulated all osteogenic markers and increased the expression of Notch4, Dll4, Hey1, Hes1 and Hes5 in osteogenic medium compared to control. In the presence of DAPT and SAHM1, used as Notch pathway inhibitors, the expression of the osteogenic markers, including Runx2, Dlx5, Osterix, as well as Hes1 and Hes5 were significantly inhibited, both in unexposed and PEMF-exposed hMSCs. These results suggest that activation of Notch pathway is required for PEMFs-stimulated osteogenic differentiation. These new findings may be useful to improve autologous cell-based regeneration of bone defects in orthopaedics.

Osteogenic differentiation is a multi-step process controlled by a complex molecular framework. Notch is an evolutionarily conserved intercellular signaling pathway playing a prominent role in cell fate and differentiation, although the mechanisms by which this pathway regulates osteogenesis remain controversial. This study aimed to investigate, in vitro, the involvement of Notch pathway during all the developmental stages of osteogenic differentiation in human osteosarcoma cell line MG63. Cells were cultured in basal condition (control) and in osteoinductive medium (OM). Notch inhibitors were also added in OM to block Notch pathway. During osteogenic differentiation, early (alkaline phosphatase activity and collagen type I) and late osteogenic markers (osteocalcin levels and matrix mineralization), as well as the gene expression of the main osteogenic transcription factors (Runx2, Osterix, and Dlx5) increased. Time dependent changes in the expression of specific Notch receptors were identified in OM versus control with a significant reduction in the expression of Notch1 and Notch3 receptors in the early phase of differentiation, and an increase of Notch2 and Notch4 receptors in the late phase. Among Notch nuclear target genes, Hey1 expression was significantly higher in OM than control, while Hes5 expression decreased. Osteogenic markers were reduced and Hey1 was significantly inhibited by Notch inhibitors, suggesting a role for Notch through the canonical pathway. In conclusion, Notch pathway might be involved with a dual role in osteogenesis of MG63, through the activation of Notch2, Notch4, and Hey1, inducing osteoblast differentiation and the depression of Notch1, Notch3, and Hes5, maintaining an undifferentiated status. J. Cell. Physiol. 231: 2652-2663, 2016. © 2016 Wiley Periodicals, Inc.

Electrochemotherapy is an emerging local treatment for the management of superficial tumors and, among these, also chest wall recurrences from breast cancer. Generally, the treatment of this peculiar type of tumor requires the coverage of large skin areas. In these cases, electrochemotherapy treatment by means of standard small size needle electrodes (an array of 0.73 cm spaced needles, which covers an area of 1.5 cm2) is time-consuming and can allow an inhomogeneous coverage of the target area. We have previously designed grid devices suitable for treating an area ranging from 12 to 200 cm2. In this study, we propose different approaches to study advantages and drawbacks of a grid device with needles positioned 2 cm apart. The described approach includes a numerical evaluation to estimate electric field intensity, followed by an experimental quantification of electroporation on a cell culture. The electric field generated in a conductive medium has been studied by means of 3-dimensional numerical models with varying needle pair distance from 1 to 2 cm. In particular, the electric field evaluation shows that the electric field intensity with varying needle distance is comparable in the area in the middle of the 2 electrodes. Differently, near needles, the electric field intensity increases with the increasing electrode distance and supply voltage. The computational results have been correlated with experimental ones obtained in vitro on cell culture. In particular, electroporation effect has been assessed on human breast cancer cell line MCF7, cultured in monolayer. The use of 2-cm distant needles, supplied by 2000 V, produced an electroporation effect in the whole area comprised between the electrodes. Areas of cell culture where reversible and irreversible electroporation occurred were identified under microscope by using fluorescent dyes. The coupling of computation and experimental results could be helpful to evaluate the effect of the needle distance on the electric field intensity in cell cultures in terms of reversible or irreversible electroporation.

Electrochemotherapy (ECT) is a local anticancer treatment based on the combination of chemotherapy and short, tumor-permeabilizing, voltage pulses delivered using needle electrodes or plate electrodes. The application of ECT to large skin surface tumors is time consuming due to technical limitations of currently available voltage applicators. The availability of large pulse applicators with few and more spaced needle electrodes could be useful in the clinic, since they could allow managing large and spread tumors while limiting the duration and the invasiveness of the procedure. In this article, a grid electrode with 2-cm spaced needles has been studied by means of numerical models. The electroporation efficiency has been assessed on human osteosarcoma cell line MG63 cultured in monolayer. The computational results show the distribution of the electric field in a model of the treated tissue. These results are helpful to evaluate the effect of the needle distance on the electric field distribution. Furthermore, the in vitro tests showed that the grid electrode proposed is suitable to electropore, by a single application, a cell culture covering an area of 55 cm2. In conclusion, our data might represent substantial improvement in ECT in order to achieve a more homogeneous and time-saving treatment, with benefits for patients with cancer.

Pulsed electromagnetic fields (PEMFs) play a regulatory role on osteoblast activity and are clinically beneficial during fracture healing. Human mesenchymal stem cells (MSCs) derived from different sources have been extensively used in bone tissue engineering. Compared with MSCs isolated from bone marrow (BMSCs), those derived from adipose tissue (ASCs) are easier to obtain and available in larger amounts, although they show a less osteogenic differentiation potential than BMSCs. The hypothesis tested in this study was to evaluate whether PEMFs favor osteogenic differentiation both in BMSCs and in ASCs and to compare the role of PEMFs alone and in combination with the biochemical osteogenic stimulus bone morphogenetic protein (BMP)-2. Early and later osteogenic markers, such as alkaline phosphatase (ALP) activity, osteocalcin levels, and matrix mineralization, were analyzed at different times during osteogenic differentiation. Results showed that PEMFs induced osteogenic differentiation by increasing ALP activity, osteocalcin, and matrix mineralization in both BMSCs and ASCs, suggesting that PEMF activity is maintained during the whole differentiation period. The addition of BMP-2 in PEMF exposed cultures further increased all the osteogenic markers in BMSCs, while in ASCs, the stimulatory role of PEMFs was independent of BMP-2. Our results indicate that PEMFs may stimulate an early osteogenic induction in both BMSCs and ASCs and they suggest PEMFs as a bioactive factor to enhance the osteogenesis of ASCs, which are an attractive cell source for clinical applications. In conclusion, PEMFs may be considered a possible tool to improve autologous cell-based regeneration of bone defects in orthopedics.

Osteoarthritis (OA) is a joint pathology characterized by fibrillation, reduced cartilage thickness and subchondral bone sclerosis. There is evidence that pulsed electromagnetic fields (PEMFs) counteract OA progression, but the effect of two different PEMF frequencies has not yet been shown. The aim of this study was to test the effectiveness of PEMFs at two different frequencies (37 and 75 Hz) in a late OA stage in 21-month-old Guinea pigs. After 3 months of 6 h/day PEMF stimulation, histological and histomorphometric analyses of the knees were performed. At both frequencies, PEMFs significantly reduced histological cartilage score, fibrillation index (FI), subchondral bone thickness (SBT) and trabecular number (Tb.N) and increased trabecular thickness (Tb.Th) and separation (Tb.Sp) in comparison to the not treated SHAM group. However, PEMFs at 75 Hz produced significantly more beneficial effects on the histological score and FI than 37 Hz PEMFs. At 75 Hz, PEMFs counteracted cartilage thinning as demonstrated by a significantly higher cartilage thickness values than either those of the SHAM or 37 Hz PEMF-treated groups. Although in severe OA both PEMF frequencies were able to limit its progression, 75 Hz PEMF stimulation achieved the better results.

Osteoarthritis (OA) is a common joint disease associated with articular cartilage degeneration. To improve the therapeutic options of OA, tissue engineering based on the use of mesenchymal stem cells (MSCs) has emerged. However, the presence of inflammatory cytokines, such as interleukin-1β (IL-1β), during chondrogenesis reduces the efficacy of cartilage engineering repair procedures by preventing chondrogenic differentiation. Previous studies have shown that electromagnetic fields (EMFs) stimulate anabolic processes in OA cartilage and limit IL-1β catabolic effects. We investigated the role of EMFs during chondrogenic differentiation of MSCs, isolated from bovine synovial fluid, in the absence and presence of IL-1β. Pellets of MSCs were differentiated for 3 and 5 weeks with transforming growth factor-β3 (TGFβ3), in the absence and presence of IL-1β and exposed or unexposed to EMFs. Biochemical, quantitative real-time RT-PCR and histological results showed that EMFs alone or in the presence of TGFβ3 play a limited role in promoting chondrogenic differentiation. Notably, in the presence of IL-1β and TGFβ3 a recovery of proteoglycan (PG) synthesis, PG content and aggrecan and type II collagen mRNA expression in the EMF-exposed compared to unexposed pellets was observed. Also, histological and immunohistochemical results showed an increase in staining for alcian blue, type II collagen and aggrecan in EMF-exposed pellets. In conclusion, this study shows a significant role of EMFs in counteracting the IL-1β-induced inhibition of chondrogenesis, suggesting EMFs as a therapeutic strategy for improving the clinical outcome of cartilage engineering repair procedures, based on the use of MSCs.

In this paper, the electric field generated in a conductive medium by needles pairs with inter-needle distance of 1 or 2 cm has been studied by means of 3D numerical models. The computational results have been correlated with experimental ones obtained in vitro on cultured cells. In particular, electroporation effect has been assessed on human osteosarcoma cell line MG63 cultured in monolayer. These results are helpful to evaluate the effect of the needle distance on the electric field distribution in cultured cells in terms of occurrence of reversible or irreversible electroporation.

Background: MTHFR gene polymorphisms has been shown to be associated with methotrexate (MTX) toxicity in adult hematological malignancies; however, the results remain inconclusive. Materials & methods: To examine the role of common MTHFR variants in MTX toxicity prediction, we performed a meta-analysis via identifying relevant studies for quantitative data pooling. Results: Our results showed a significant association between MTHFR C677T polymorphism and increased risk of MTX-induced all-grade (grade 1–4) and severe (grade 3–4) hepatic and gastrointestinal toxicities in Caucasian independent of MTX dosage. MTHFR 677T allele increased risk of severe mucositis and all-grade hematological toxicity. MTHFR A1298C polymorphism was not significantly associated with hepatic and hematological toxicity, whereas perhaps having a protective effect on mucositis and gastrointestinal toxicity. Conclusion: MTHFR C677T polymorphism may be a good predictor for MTX toxicity in adult hematological malignancies.

Synovial fibroblasts (SFs) contribute to the development of osteoarthritis (OA) by the secretion of a wide range of pro-inflammatory mediators, including cytokines and lipid mediators of inflammation. Previous studies suggest that electromagnetic fields (EMFs) may represent a potential therapeutic approach to limit cartilage degradation and control inflammation associated to OA, and that they may act through the adenosine pathway. Therefore, we investigated whether EMFs might modulate inflammatory activities of human SFs from OA patients (OASFs) treated with interleukin-1β (IL-1β), and the possible involvement of adenosine receptors (ARs) in mediating EMF effects. EMF exposure induced a selective increase in A(2A) and A(3) ARs. These increases were associated to changes in cAMP levels, indicating that ARs were functionally active also in EMF-exposed cells. Functional data obtained in the presence of selective A(2A) and A(3) adenosine agonists and antagonists showed that EMFs inhibit the release of prostaglandin E(2) (PGE(2)) and the proinflammatory cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8), while stimulating the release of interleukin-10 (IL-10), an antinflammatory cytokine. These effects seem to be mediated by the EMF-induced upregulation of A(2A) and A(3) ARs. No effects of EMFs or ARs have been observed on matrix degrading enzyme production. In conclusion, this study shows that EMFs display anti-inflammatory effects in human OASFs, and that these EMF-induced effects are in part mediated by the adenosine pathway, specifically by the A(2A) and A(3) AR activation. Taken together, these results open new clinical perspectives to the control of inflammation associated to joint diseases.

BACKGROUND AND PURPOSE Adenosine is an endogenous modulator, interacting with four G-protein coupled receptors (A(1), A(2A), A(2B) and A(3)) and acts as a potent inhibitor of inflammatory processes in several tissues. So far, the functional effects modulated by adenosine receptors on human synoviocytes have not been investigated in detail. We evaluated mRNA, the protein levels, the functional role of adenosine receptors and their pharmacological modulation in human synoviocytes. EXPERIMENTAL APPROACH mRNA, Western blotting, saturation and competition binding experiments, cyclic AMP, p38 mitogen-activated protein kinases (MAPKs) and nuclear factor (NF)-kappaB activation, tumour necrosis factor alpha (TNF-alpha) and interleukin-8 (IL-8) release were assessed in human synoviocytes isolated from patients with osteoarthritis. KEY RESULTS mRNA and protein for A(1), A(2A), A(2B) and A(3) adenosine receptors are expressed in human synoviocytes. Standard adenosine agonists and antagonists showed affinity values in the nanomolar range and were coupled to stimulation or inhibition of adenylyl cyclase. Activation of A(2A) and A(3) adenosine receptors inhibited p38 MAPK and NF-kappaB pathways, an effect abolished by selective adenosine antagonists. A(2A) and A(3) receptor agonists decreased TNF-alpha and IL-8 production. The phosphoinositide 3-kinase or G(s) pathways were involved in the functional responses of A(3) or A(2A) adenosine receptors. Synoviocyte A(1) and A(2B) adenosine receptors were not implicated in the inflammatory process whereas stimulation of A(2A) and A(3) adenosine receptors was closely associated with a down-regulation of the inflammatory status. CONCLUSIONS AND IMPLICATIONS These results indicate that A(2A) and A(3) adenosine receptors may represent a potential target in therapeutic modulation of joint inflammation.

Summary Objective To investigate the role of adenosine analogs and electromagnetic field (EMF) stimulation on prostaglandin E 2 (PGE 2 ) release and cyclooxygenase-2 (COX-2) expression in bovine synovial fibroblasts (SFs). Methods SFs isolated from synovia were cultured in monolayer. Saturation and binding experiments were performed by using typical adenosine agonists: N 6-cyclohexyladenosine (CHA, A 1 ), 2-[ p -(2-carboxyethyl)-phenetyl-amino]-5′- N -ethylcarboxamidoadenosine (CGS 21680, A 2A ), 5′- N -ethylcarboxamidoadenosine (NECA, non-selective), N 6-(3-iodobenzyl)2-chloroadenosine-5′- N -methyluronamide (Cl-IB-MECA, A 3 ). SFs were treated with TNF-α (10ng/ml) and lipopolysaccharide (LPS) (1μg/ml) to activate inflammatory response. Adenosine analogs were added to control and TNF-α- or LPS-treated cultures both in the absence and in the presence of adenosine deaminase (ADA) which is used to deplete endogenous adenosine. Parallel cultures were exposed to EMFs (75Hz, 1.5mT) during the period in culture (24h). PGE 2 release was measured by immunoassay. COX-2 expression was evaluated by RT-PCR. Results TNF-α and LPS stimulated PGE 2 release. All adenosine agonists, except for Cl-IB-MECA, significantly inhibited PGE 2 production. EMFs inhibited PGE 2 production in the absence of adenosine agonists and increased the effects of CHA, CGS 21680 and NECA. In ADA, the inhibition on PGE 2 release induced by CHA, CGS and NECA was stronger than in the absence of ADA and the EMF-inhibitory effect was lost. Changes in PGE 2 levels were associated to modification of COX-2 expression. Conclusions This study supports anti-inflammatory activities of A 1 and A 2A adenosine receptors and EMFs in bovine SFs. EMF activity appears mediated by an EMF-induced up-regulation of A 2A receptors. Biophysical and/or pharmacological modulation of adenosine pathways may play an important role to control joint inflammation.

Summary Objective The aim of the present study is that of characterizing, for the first time in a quantitative way, from a biochemical, physico chemical and functional point of view P2X 1 and P2X 3 purinergic receptors in bovine chondrocytes. The affinity and the potency of typical purinergic ligands were studied through competition binding experiments and their role in modulating chondrocyte actvities was investigated by analyzing nitric oxide (NO) and prostaglandin E2 (PGE 2 ) release. Methods Saturation, competition binding experiments, western blotting and immunohistochemistry assays on the P2X 1 and P2X 3 purinergic receptors in bovine chondrocytes were performed. Thermodynamic analysis of the P2X 1 and P2X 3 purinergic binding was studied to investigate the forces driving drug-receptor coupling. In the functional assays (NO and PGE 2 release) the potency of purinergic agonists and antagonists was evaluated. Results Bovine chondrocytes expressed P2X 1 and P2X 3 purinergic receptors and thermodynamic parameters indicated that purinergic binding is enthalpy- and entropy-driven for agonists and totally entropy-driven for antagonists. Typical purinergic agonists such as adenosine 5′-triphosphate (ATP) and α,β-methyleneATP were able to increase NO and PGE 2 release. A purinergic antagonist, A317491, was able to block the stimulatory effect on functional experiments mediated by the agonists. Conclusions These data demonstrate for the first time the presence of functional P2X 1 and P2X 3 purinergic receptors in bovine chondrocytes. Agonists and antagonists are thermodynamically discriminated and are able to modulate functional responses such as NO and PGE 2 release. These results suggest the potential role of novel purinergic antagonists in the treatment of pathophysiological diseases linked to the inflammation and involved in articular cartilage resorption.

Background and Objectives Common methylenetetrahydrofolate reductase gene variants (MTHFR C677T and A1298C) have been described to have opposite effects on cancer patients. They may reduce cancer susceptibility and increase drug-related toxicity when folate antagonists (e.g. methotrexate) are utilized. We analyzed 110 patients with high-grade non-Hodgkin’s lymphoma (NHL), 68 of whom were eligible for a chemotherapy combination containing methotrexate (MACOP-B) and 42 for chemotherapy without methotrexate (CHOP).Design and Methods Patients were genotyped by polymerase chain reaction and stratified by MTHFR variants. These data were related to the toxicity (WHO grade GO-4) that the patients suffered and their survival. Overall 64 cases (58.2%) developed some form of toxicity and 23 (20.9%) had grade 3/4 toxicity.Results When considering toxicity of any grade (grade 1–4), the 677TT genotype was significantly over-represented among cases with mucositis (OR=4.85; 95%CI, 1.47–15.97; p=0.009) and those with hepatic toxicity (OR=3.43; 95%CI, 0.99–11.86; p=0.052). Sub-analyses in the group treated with MACOP-B showed a slight increase in the risk of developing mucositis (OR=5.22; 95%CI, 1.20–27.27; p=0.03), and a strong increase in the risk of hepatic toxicity (OR=7.08; 95%CI, 1.38–36.2; p=0.019) and thrombocytopenia (OR=7.69, 95%CI 1.0–58.94; p=0.05). Interestingly, compared to the risk of developing toxicity of any grade, the risk of developing severe (grade 3/4) mucositis was almost doubled in the whole group of cases with 677TT (OR=8.13; 95%CI 1.61–41.04; p=0.011) and dramatically increased in the MACOP-B-treated cases with this gene variant (OR=24.6; 95%CI 2.49–87.41; p=0.001). There were significant results for 1298CC cases exclusively for mucositis (any grade, OR=5.33; 95%CI, 1.25–22.70; p=0.023 and OR=9.15; 95%CI, 1.14–73.41; p=0.037; for the whole group and the MACOP-B-treated group, respectively). Similarly, the risk of 1298CC patients developing severe mucositis increased (OR=9.24; 95%CI, 1.47–58.0; p=0.017 and OR=11.53; 0.93–143.18; p=0.057; in the whole group and in the MACOP-B-treated group, respectively). Event-free survival analysis revealed a lower probability of event-free survival at 5 years for 677T-carriers (log-ranks, p=0.05 and p=0.07 in the whole group and in the MACOP-B-treated group, respectively). More significant results were obtained when 1298CC cases were excluded from the reference group (log-ranks, p=0.03 and p=0.04, respectively). No significant associations were found in the CHOP-treated group.Interpretation and Conclusions Our data suggest that MTHFR gene variants play a critical role in NHL outcome, possibly by interfering with the action of methotrexate with significant effects on toxicity and survival. Genotyping of folate pathway gene variants might be useful to enable reduction of chemotherapy toxicity and/or to improve survival by indicating when dose adjustments or alternative treatments are necessary.

Summary Objective To investigate the role of pulsed electromagnetic field (PEMF) exposure parameters (exposure length, magnetic field peak amplitude, pulse frequency) in the regulation of proteoglycan (PG) synthesis of bovine articular cartilage explants. Methods Bovine articular cartilage explants were exposed to a PEMF (75Hz; 2mT) for different time periods: 1, 4, 9, 24h. Then, cartilage explants were exposed for 24h to PEMFs of different magnetic field peak amplitudes (0.5, 1, 1.5, 2mT) and different frequencies (2, 37, 75, 110Hz). PG synthesis of control and exposed explants was determined by Na 2 - 35 SO 4 incorporation. Results PEMF exposure significantly increased PG synthesis ranging from 12% at 4h to 17% at 24h of exposure. At all the magnetic field peak amplitude values, a significant PG synthesis increase was measured in PEMF-exposed explants compared to controls, with maximal effect at 1.5mT. No effect of pulse frequency was observed on PG synthesis stimulation. Conclusions The results of this study show the range of exposure length, PEMF amplitude, pulse frequency which can stimulate cartilage PG synthesis, and suggest optimal exposure parameters which may be useful for cartilage repair in in vivo experiments and clinical application.

Background Osteoarthritis (OA) is the final result of progressive alterations to articular cartilage structure, composition and cellularity, followed by an increase in the concentration of pro-inflammatory cytokines in joint synovial fluid. Even though the effect of pulsed electromagnetic field (PEMF) stimulation in counteracting OA progression and inflammation is of increasing interest, because of its anabolic and anti-inflammatory properties, the present study aimed to improve the knowledge on cartilage extracellular matrix (ECM) and chondrocyte changes related to the exposure of PEMF, from a histological and histomorphometric point of view. Methods An in vitro OA model was realized, culturing bovine cartilage explants with a high dose of interleukin 1β (IL1β, 50 ng/ml) at different experimental times (24 h, and 7 and 21 days). The effects of PEMFs (75 Hz, 1.5 mT) were evaluated in cartilage explants treated with IL1β or not (control), in terms of cartilage structure, cellularity and proteoglycans, glycosaminoglycans, collagen II and transforming growth factor β1 synthesis by using histology, histomorphometry and immunohistochemistry. Results Making a comparison with control cartilage, IL1β-treated explants showed a decrease in cartilage matrix, structure and cellularity parameters. PEMFs were able to counteract the progression of OA acting on both cartilage cellularity and ECM in cartilage previously treated with IL1β. Normal distribution (Kolmogroc-Smirnov test) and homoscedasticity (Levene test) of data were verified, then, the non-parametric Kruskal Wallis test followed by Mann-Whiteny U test for pairwise comparisons were performed. The p-value was adjusted according to the Dunn-Sidak correction. Conclusions These results, obtained by culturing and treating cartilage explants from two different joints, confirmed that PEMF stimulation can be used as adjuvant therapy to preserve cartilage from detrimental effects of high inflammatory cytokine levels during OA.

Melphalan represents the reference drug for locoregional chemotherapy of melanoma; nevertheless, treatment failure may occur because of resistance to chemotherapy. Refractory melanoma cells show either an increased capability of drug inactivation, which is known to be associated with elevated intracellular levels of glutathione (GSH), or a decreased melphalan uptake. The aim of this study was to explore a biochemical and a biophysical strategy, and their combination, to overcome melphalan resistance in melanoma cells. The biochemical strategy was based on the treatment of melanoma cells with DL-buthionine (S,R)-sulfoximine (BSO) to deplete the GSH levels, thus reducing melphalan inactivation. In the biophysical strategy, cell membrane electroporation was used to increase melphalan uptake. The SK-MEL 28-resistant human melanoma cell line was pretreated with 50 μmol/l BSO for 24 h and then treated with increasing melphalan doses, with or without electroporation. Spectrophotometric quantification of cell viability was used to determine melphalan cytotoxicity. Intracellular total GSH was measured using a kinetic enzymatic assay. BSO induced 3.50-fold GSH depletion in untreated cells and a similar reduction was also maintained in melphalan-treated cells. BSO pretreatment produced a 2.46-fold increase in melphalan cytotoxicity. Electroporation increased melphalan cytotoxicity 1.42-fold. The combination of both BSO pretreatment with melphalan plus electroporation led to a 4.40-fold increase in melphalan cytotoxicity compared with melphalan alone. Pretreatment with BSO and cell membrane permeabilization by electroporation enhanced the cytotoxic activity of melphalan in melanoma cells. Their rational combination deserves further investigation and may improve the efficacy of locoregional chemotherapy of melanoma.

Summary Objective To investigate the single and combined effects of electromagnetic field (EMF) exposure and the insulin growth factor-I (IGF-I) on proteoglycan (PG) synthesis of bovine articular cartilage explants and chondrocytes cultured in monolayers. Design Bovine articular cartilage explants and chondrocyte monolayers were exposed to EMF (75Hz; 1.5mT) for 24h in the absence and in the presence of both 10% fetal bovine serum (FBS) and IGF-I (1–100ng/ml). PG synthesis was determined by Na 2 – 35 SO 4 incorporation. PG release into culture medium was determined by the dimethylmethylene blue (DMMB) assay. Results In cartilage explants, EMF significantly increased 35 S-sulfate incorporation both in the absence and in the presence of 10% FBS. Similarly, IGF-I increased 35 S-sulfate incorporation in a dose-dependent manner both in 0% and 10% FBS. At all doses of IGF-I, the combined effects of the two stimuli resulted additive. No effect was observed on medium PG release. Also in chondrocyte monolayers, IGF-I stimulated 35 S-sulfate incorporation in a dose-dependent manner, both in 0% and 10% FBS, however, this was not modified by EMF exposure. Conclusions The results of this study show that EMF can act in concert with IGF-I in stimulating PG synthesis in bovine articular cartilage explants. As this effect is not maintained in chondrocyte monolayers, the native cell–matrix interactions in the tissue may be fundamental in driving the EMF effects. These data suggest that in vivo the combination of both EMF and IGF may exert a more chondroprotective effect than either treatment alone on articular cartilage.

Matrix metalloproteinases (MMPs) are overexpressed in venous leg ulcers, determining a breakdown of the main extracellular matrix (ECM) components owing mainly to collagenase activities, and so playing a crucial role in ulcer pathogenesis. The authors studied the effects of coagulation factor XIII (FXIII), which cross-links collagen and other ECM components, in human fibroblast cultured cells in the presence and in the absence of matrix metalloproteinases from Clostridium histolyticum collagenase. Clostridium collagenase at concentrations of 2.0, 1.0, and 0.5 mg/mL was added to normal human dermal fibroblasts cultured in the presence of 0.0, 1.0, and 5.0 U/mL of FXIII concentrate (Fibrogammin P, Aventis Behring). Cell counting and metabolically active fibroblast evaluation in the cultures were monitored for 72 hours, by means of trypan-blue dye and MTT test, respectively. The MTT test showed that at the highest collagenase concentration (2.0 mg/mL), the cell number decreased more than 95% in 72 hours of treatment and no significant differences were observed regardless of the FXIII concentrations utilized. At lower collagenase concentration (1.0 mg/mL), in absence or in presence of FXIII (1.0 U/mL), the cell number decreased by about 80% in 72 hours. In contrast, in the presence of higher FXIII levels (5.0 U/mL), cells suffered globally significantly less collagenase effects (p=0.011) and the gain was appreciable at each time tested. Finally, at 0.5 mg/mL of collagenase concentration, in the absence of FXIII, the cell number decreased by about 60% in 72 hours, whereas in presence of FXIII 1.0 U/mL and 5.0 U/mL, cells decreased significantly less, by about 35% and 20%, respectively (p

Item does not contain fulltext Methotrexate (MTX), one of the important pillars in the treatment of different forms of cancer, is associated with the development of hepatotoxicity. The 677C>T variant (rs1801133) in the methylenetetrahydrofolate reductase (MTHFR) gene might affect the development of hepatotoxicity. Results in literature are, however, contradictive. The aim of this study was to evaluate the role of the MTHFR 677C>T polymorphism in MTX-induced hepatotoxicity by analyzing a Dutch cohort of pediatric patients treated with high doses of MTX and subsequently performing a meta-analysis. Ninety-eight patients receiving 542 courses of high-dose MTX were genotyped for the MTHFR 677C>T variant. Hepatotoxicity was evaluated retrospectively according to common terminology criteria for adverse events-National Cancer Institute criteria. The influence of MTHFR 677C>T on hepatotoxicity was examined using a generalized estimating equation (GEE) analysis. A fixed-effect meta-analysis based on this and previous studies investigating the association between the MTHFR 677C>T polymorphism and uniformly coded hepatotoxicity was performed. The GEE analysis showed an increased risk of developing hepatotoxicity for T versus C allele (odds ratio (OR) 1.8; 95% confidence interval (CI) 1.0-3.2, P=0.04). This finding was not supported by the meta-analysis including seven studies and 1044 patients; the OR for the 677T versus C allele was 1.1 (95% CI 0.84-1.5, P=0.25). Heterogeneity between studies was observed, possibly related to differences in MTX dose and leucovorin rescue. In conclusion, in patients with cancer, the MTHFR 677T allele has only a minor role in the development of MTX-induced hepatotoxicity. Observed heterogeneity between studies warrants further study into (tailored) leucovorin rescue.

To evaluate the efficacy and toxicity of electrochemotherapy (ECT) in elderly metastatic breast cancer (BC) patients. Retrospective analysis of 55 patients with superficial metastases who underwent ECT according to the European Standard Operative Procedures of electrochemotherapy. Treatment schedule consisted of intravenous or intratumoral bleomycin followed by locally delivered electric pulses. Statistical comparisons were performed between two groups: the patients aged

Pulsed electromagnetic fields (PEMFs) play a regulatory role on osteoblast activity and are clinically beneficial during fracture healing. Human mesenchymal stem cells (MSCs) derived from different sources have been extensively used in bone tissue engineering. Compared with MSCs isolated from bone marrow (BMSCs), those derived from adipose tissue (ASCs) are easier to obtain and available in larger amounts, although they show a less osteogenic differentiation potential than BMSCs. The hypothesis tested in this study was to evaluate whether PEMFs favor osteogenic differentiation both in BMSCs and in ASCs and to compare the role of PEMFs alone and in combination with the biochemical osteogenic stimulus bone morphogenetic protein (BMP)-2. Early and later osteogenic markers, such as alkaline phosphatase (ALP) activity, osteocalcin levels, and matrix mineralization, were analyzed at different times during osteogenic differentiation. Results showed that PEMFs induced osteogenic differentiation by increasing ALP activity, osteocalcin, and matrix mineralization in both BMSCs and ASCs, suggesting that PEMF activity is maintained during the whole differentiation period. The addition of BMP-2 in PEMF exposed cultures further increased all the osteogenic markers in BMSCs, while in ASCs, the stimulatory role of PEMFs was independent of BMP-2. Our results indicate that PEMFs may stimulate an early osteogenic induction in both BMSCs and ASCs and they suggest PEMFs as a bioactive factor to enhance the osteogenesis of ASCs, which are an attractive cell source for clinical applications. In conclusion, PEMFs may be considered a possible tool to improve autologous cell-based regeneration of bone defects in orthopedics.

To investigate simultaneously a defect affecting the protein C/protein S (PC/PS) anticoagulant pathway is possible thanks to a methodological approach (ProC(R) Global; Dade Behring) based on the activation of endogenous plasma PC by a snake venom extract. Factor V (FV) Leiden, the most frequent cause of hereditary thrombosis, is well detected by the test with sensitivity of 100% irrespective of the presence/absence of thrombosis in the subjects investigated. The test is also suited to detect PC or PS defect, but in this case the in vitro impairment of the PC/PS pathway is less pronounced particularly for PS defects (sensitivity for PC and PS defect, 85-100 and 30-90%, respectively). In this study, we hypothesized that the lower sensitivity described for PS defect, compared with those of PC and FV Leiden defects, could also be related to the clinical condition of the subject investigated (symptomatic/asymptomatic) rather than solely to the PS plasma activity/level. Therefore, we analyzed 126 subjects with single congenital defects in the PC/PS pathway: 46 subjects with PS deficiency (26 thrombotic cases and 20 asymptomatic relatives), 40 subjects with PC deficiency (25 thrombotic cases and 15 asymptomatic relatives), and 40 heterozygous FV Leiden subjects (25 thrombotic cases and 15 asymptomatic relatives). By a cut-off of normalized Agkistrodon contortix snake venom ratio of 0.84, the sensitivity in the whole group of cases (sensitivity a) was 76.1, 95.0 and 100%, respectively, for PS, PC and FV Leiden defects. The test failed to detect 11 (23.9%) among the 46 PS-deficient subjects, and all these cases except two belonged to the asymptomatic subgroup (9/20; 45%). Excluding the 20 asymptomatic relatives, the new sensitivity (sensitivity b) for the PS defect was 92.3%. The comparison of the sensitivity in the symptomatic PS cases and in the asymptomatic ones was significantly different (P = 0.010). Among the 40 PC-deficient subjects, only two (5.0%) were not detected by the test and they belonged indifferently to the two subgroups. Finally, none of the 40 FV Leiden heterozygotes were misdiagnosed by the test. These results suggest that in symptomatic PS-deficient cases the test could reflect a post-thrombotic effect and/or reveal potential unidentified prothrombotic influences assessing a prothrombotic risk condition.

Electroporation is an effective method to deliver drugs into tumor cells to kill them, by applying a pulsed electric field to the cellular membrane. Existing electrodes consist of clamping claws or arrays of needles and can be effectively applied only to small areas. New electrodes that can treat large areas are sought; flexibility is needed to adapt to irregular tumor shape and, to be folded to enter from small surgical opening. In this work we present the design and test of a 16 cm2 flexible electrode for electroporation with biosensing capabilities, built with standard flexible circuit technologies enclosed in a biocompatible package. The electrode contains electronics to provide cryptography-based identification to the electroporation machine to avoid setup errors and protection against use of counterfeited electrodes. In-vitro tests of the electrode show that electroporation occurs up to a depth of 8 mm with 100% electroporation efficiency over the 30% of electrode area. Temperature rise on the electrode during treatment does not exceed 6 degrees celsius, a value that not causes damage to the cells.

Human leukocyte antigen (HLA)-G molecules are nonclassical HLA class I antigens expressed as membrane bound and soluble isoforms (sHLA-G) with a restricted tissue distribution and anti-inflammatory functions. Because inflammation is involved in the pathogenesis of osteoarthritis (OA), we have analyzed the expression and production of HLA-G molecules in in vitro cultured synovial fibroblasts (SFs) from OA patients and control subjects. We have analyzed the levels of sHLA-G1 and HLA-G5 isoforms by immunoenzymatic assay (enzyme-linked immunosorbent assay) in the SF culture supernatants from six OA patients and six control subjects in 70-day in vitro cultures and after the addition of lipopolysaccharide or recombinant interleukin (IL)-10 (rIL-10). We have confirmed HLA-G modulation by cytofluorimetry and immunofluorescence. The results have demonstrated the spontaneous production of sHLA-G1 molecules by both OA and control SFs. The expression was confirmed by cytofluorimetry and immunofluorescence. OA SFs produce both sHLA-G1 and HLA-G5 molecules during the first 23 days of culture and higher levels of sHLA-G1 during the first 40 days of in vitro culture and after lipopolysaccharide or rIL-10 activation compared with control SFs. The production of HLA-G1 molecules, constitutively expressed by control and OA SFs, is significantly increased in OA, suggesting a possible mechanism to counteract the inflammation of the synovial joints.

Folate and its derivatives are pivotal for cell cycle and proliferation. They facilitate the crosstalk between DNA synthesis and methylation crucial processes in cancer establishment [1]. Dietary folate or supplements (e.g., folic acid) must be fully reduced by dihydrofolate reductase (DHFR) before entering cell metabolism [1]. DHFR is responsible for dihydrofolate (DHF) to tetrahydrofolate (THF) conversion, as well as for assisting the generation of additional partially reduced folates (i.e., methylene-THF and formyl-THF), which are then transformed into the fully active folate (i.e., methyl-THF) with the help of methylenetetrahydrofolate reductase (MTHFR). As the main folate isoforms involved in DNA synthesis and methylation are handled by these two key enzymes, alterations in DHFR and/or in MTHFR functions may have detrimental effects on DNA stability and cancer susceptibility [2-5].

Background The antifolate agent methotrexate is an important component of maintenance therapy in acute lymphoblastic leukemia, although methotrexate-related toxicity is often a reason for interruption of chemotherapy. Prediction of toxicity is difficult because of inter-individual variability susceptibility to antileukemic agents. Methotrexate interferes with folate metabolism leading to depletion of reduced folates.Design and Methods The aim of this study was to investigate the influence of polymorphisms for folate metabolizing enzymes with respect to toxicity and survival in adult patients with acute lymphoblastic leukemia treated with methotrexate maintenance therapy. To this purpose, we evaluated possible associations between genotype and hematologic and non-hematologic toxicity and effects on survival at 2 years of follow-up in patients with acute lymphoblastic leukemia.Results Polymorphisms in the genes encoding for methylenetetrahydrofolate reductase (MTHFR 677C>T) and in dihydrofolate reductase (DHFR 19 bp deletion) significantly increased the risk of hepatotoxicity in single (odds ratio 5.23, 95% confidence interval 1.13–21.95 and odds ratio 4.57, 95% confidence interval 1.01–20.77, respectively) and in combined analysis (odds ratio 6.82, 95% confidence interval 1.38–33.59). MTHFR 677C>T also increased the risk of leukopenia and gastrointestinal toxicity, whilst thymidylate synthase 28 bp repeat polymorphism increased the risk of anemia (odds ratio 8.48, 95% confidence interval 2.00–36.09). Finally, patients with MTHFR 677TT had a decreased overall survival rate (hazard ratio 2.37, 95% confidence interval 1.46–8.45).Conclusions Genotyping of folate polymorphisms might be useful in adult acute lymphoblastic leukemia to optimize methotrexate therapy, reducing the associated toxicity with possible effects on survival.

BACKGROUND Wound healing is a biologic process that is altered in patients affected by chronic venous ulcers. The wound microenvironment is reflected in the chronic wound fluid (CWF), an exudate containing serum components and tissue-derived proteins. OBJECTIVES We investigated the effects of increasing doses of CWF collected from patients suffering from chronic venous ulcers on human adult dermal fibroblasts cultured in vitro and the relationship among CWF effects and treatment length. METHODS Fibroblasts were treated with 60, 240, and 720 microg/mL CWF for 3 and 7 days. We evaluated cell proliferation and viability by MTT and Trypan blue assay, cell morphology by light microscopy, F-actin microfilaments organization by tetramethylrhodamine B isothiocyanate-conjugated phalloidin, alpha-smooth muscle actin expression by immunofluorescence, and senescence-associated beta-galactosidase activity. RESULTS CWF induced an increase in cell proliferation in the first 3 days of treatment. In contrast, at 7 days, a strong decrease in cell viability was observed. These changes were related to a cytoskeletal F-actin reorganization and not to fibroblast-myofibroblast differentiation nor to changes in cellular senescence. CONCLUSIONS This study shows a dose-dependent and biphasic effect of CWF on dermal fibroblasts, suggesting that a continuous exposure to chronic wounds microenvironment may induce late cellular dysfunctions possibly involved in the delayed wound healing.

In this study we analyzed whether the polymorphisms 676TG in the tumor necrosis factor receptor (TNFR) II gene and -308GA in the TNFalpha promoter gene may influence the response grading to anti-TNFalpha therapy in rheumatoid arthritis. We enrolled and genotyped 105 RA patients treated with etanercept (n = 55), infliximab (n = 40) and adalimumab (n = 10) for 1 year. The clinical response was evaluated according to the ACR criteria every 3 months. Patients with TNFRII 676TG genotype was significantly associated with lower ACR response compared with 676TT genotype, at 3 (OR 3.78 95% CI 1.07-13.31) and 12 months (OR 4.30 95% CI 1.16-15.99) of treatment. No significant association between TNFalpha -308GA polymorphism and the clinical response was found. TNFRII 676TG genotype is associated with a lower response to anti-TNFalpha therapy, independently from the specific agent used. This polymorphism could become a useful genetic marker for predicting the different response grading to anti-TNFalpha therapy.

Low Factor XIII (FXIII) activity has been reported in the blood of patients with chronic venous leg ulcer (CVU). In vivo studies have described increased wound healing in CVU patients treated with FXIII concentrate, and in vitro studies have shown increased regenerative capacity in FXIII-treated fibroblasts. In addition, a common G-to-T polymorphism in the FXIIIA-subunit gene (V34L) significantly increases the activity and modifies the cross-linking properties of the FXIII molecule and this variant has been investigated as a protective factor against thrombosis, a recognized risk factor for CVU establishment. Therefore, the role of FXIII levels, FXIII V34L, FVR506Q, and FIIG20210A, common gene polymorphisms in the pathogenesis of CVU was investigated. Ninety-one patients with CVU and 195 healthy controls (91 of them sex- and age-matched) were PCR-genotyped for the FXIIIV34L, FVR506Q, and FIIG20210A substitutions and FXIIIA-subunit levels were determined by immuno-electrophoresis. The extent of the venous ulcer surface in patients was measured by computer software. The allele frequency and the genotype distribution of the FXIII polymorphism did not show significant differences between the whole group of cases and controls as well as prothrombin variants did. On the contrary, the FVR506Q variant (FV Leiden) allele was more frequent in patients, yielding a significant OR value of 5.93 (95 percent CI, 1.83-19.17; p= 0.003). Considering only CVU cases secondary to a post-thrombotic syndrome (n= 24), FV Leiden yielded a greater OR value of 16.08 (95 percent CI, 4.33-59.6; p < 0.0001). When the CVU cases were stratified by the three possible FXIII genotypes, a significant trend toward a lower mean value of the ulcerated area was clearly evident as the number of the polymorphic alleles (L34) increased in the genotype of patients (VV = 11.9 cm(2,)+/- 23.6; VL = 6.1 cm(2,)+/- 6.9; LL = 4.1 cm(2,)+/- 2.8; p= 0.01). On the other hand, FXIIIA antigen levels were similar between CVU cases and matched controls, but 11 percent of cases had FXIII deficiency (FXIIIA

Two G-to-A mutations at positions 1691 of the factor V (FV) gene and 20210 of the prothrombin (FII) gene have been associated with an increased risk of venous thromboembolism. We report a thrombosis-prone family in which one subject – the propositus who exhibited combined heterozygous FV G1691A and FII G20210A mutations – showed spontaneous and early clinical onset (at 23 years), recurrences of deep-vein thrombosis and pulmonary embolism. His asymptomatic father carried the FII G20210A substitution and his mother, characterized by an isolated thrombotic episode on occasion of surgery (at 48 years), carried the FV G1691A substitution. In the maternal lineage, one of the propositus’ uncles had thrombosis on occasion of a bone fracture (at 65 years) despite the absence of known prothrombotic defects. A sister of the propositus carried the FII G20210A and the brother the FV G1691A mutation. They have been asymptomatic until now. The propositus’ two children, 20 and 16 years old, both carry the FV G1691A substitution and have been asymptomatic until now. The plasma levels of FII were higher in carriers of the FII G20210A allele if compared with noncarriers, and the activated protein C resistance phenotype, associated with the FV Leiden mutation, showed a complete correlation with the FV G1691A mutation. Despite the very limited number of thrombotic cases involved in this survey, which does not allow statistically sound conclusions, the data obtained from this family suggest that the synergy of inherited factors and transient risk conditions could play a key role in the occurrence of thrombotic accidents.

The role of a common polymorphism in the factor XIII A-subunit gene (FXIII Val34Leu) has been recently investigated as a protective genetic factor against arterial and venous thrombosis. In addition, the less frequent Leu34 allele has been described as a risk factor for intracerebral hemorrhage. We evaluated the prevalence of this polymorphism by PCR in three case-control studies of patients diagnosed as having primary intracerebral hemorrhage (PCH, n = 130), coronary heart diseases (CHD, n = 240; myocardial infarction/no myocardial infarction, 120/120), and cerebrovascular diseases (CVD, n = 240; cerebral infarction/transient ischaemic attack, 120/120). The matched control groups consisted of patients admitted to the hospital without history of vascular disease. In addition, 200 healthy subjects were investigated. The frequency of the mutated allele (Leu34) was higher in patients with PCH than in controls (33.8% vs. 23.1%, P = 0.009) and lower in CHD and CVD patients compared to controls (18.1% vs. 25.2%, P = 0.010 and 17.3% vs. 24.2%, P = 0.011, respectively). Moreover, among the patients with CHD, the Leu34 allele was underrepresented in cases with myocardial infarction than without (12.9% vs. 23.3%, P = 0.004) and than in controls (12.9% vs. 25.2%, P < 0.001). Similar findings were obtained in patients with CVD comparing the cases with cerebral infarction versus cases with transient ischaemic attack (12.5% vs. 22.1%, P = 0.008) and versus controls (12.5% vs. 24.2%, P < 0.001). Finally, considering altogether the groups of ischaemic patients (CHD and CVD, n = 480), it was noted a trend towards a higher mean age of the clinical onset in homozygotes for the Leu allele than in the wild types (P = 0.078). This study indicates that in our population possession of the FXIII Val34Leu mutation predisposes to the occurrence of primary intracerebral hemorrhage and protects against cerebral and myocardial infarction. A wider modulatory role in the progression and onset of atherothrombotic diseases could be ascribed to FXIII Val34Leu. Am. J. Hematol. 67:183–188, 2001. © 2001 Wiley-Liss, Inc.