The actin cytoskeleton plays a key role in the stability of cell-cell junctions, adhesion and cell motility, which are crucial for tumour progression and metastases. Changes in the actin filaments ...organization could affect and increase permeability of cell monolayer due to interruption and reorganization of tight junctions in epithelial cells.In this study we investigate the combined effect of the electrioporation and miltefosine on the F-actin and ZO-1 in cancer epithelial line A549 and non-cancer cell line MDCKII. Our results showed that treatment of A549 and MDCK cells with electrical field in combination with miltefosine is cell-specific. The cancer A549 cell line was found to be more sensitive to the treatment as compared to non-cancerous cells. Actin cytoskeleton was highly disturbed while ZO-1 organization seems stabilized.Key words: miltefosine, electrical pulses, actin, ZO-1
Little is known about the influence of substratum properties and composition on the ability of cells to translocate
α5
β1 integrins and to form fibrillar adhesion. We have examined the impact of ...self-assembled monolayers (SAMs) bearing different functional end groups (amines (NH
2) or carboxylic acids (COOH)) on the presence of fibrillar adhesions in human fibroblasts attached to fibronectin-coated SAMs. Most of the fibroblasts incubated in serum-free medium for 2
h on COOH showed segregation of focal contact components (
αv integrin subunits, phosphotyrosine proteins) and fibrillar adhesions (
α5 integrin subunits, tensin) while the majority of cells plated on NH
2 did not. Analysis of fibronectin fibril formation confirmed also that human fibroblasts plated on COOH formed matrix fibrils significantly better. The surface-associated
α5 to
αv integrin ratio was smaller in cells on COOH than on NH
2 due to a decreased
α5 integrin binding. In addition, human fibroblasts migrated more readily on COOH in comparison to NH
2 which points to a different binding strength of integrins to the substratum. Overall, the results indicate that the molecular composition of substrata has a strong influence on FN matrix formation by promoting or inhibiting segregation of focal and fibrillar adhesions.
Many hemocyanins, the oxygen‐transporting proteins in some invertebrates, are studied in depth in view of their immunostimulatory and vaccine adjuvant properties. However, their direct cytotoxic ...effect on breast cancer cell lines is poorly investigated. Here, we evaluated the effect of native β‐hemocyanin from Helix pomatia (β‐HpH) and its complexes with choline amino acids (CholAA) on the viability and morphology of estrogen‐dependent (MCF‐7) and estrogen‐independent (MDA‐MB‐231) breast cancer cells. In the tested concentration range, the native ß‐HpH has no effect on the cytotoxicity and migratory capacity of the two tested cell lines. CholAA induce rearrangement in the ß‐HpH molecule. The complexes characterize with decreased thermal stability and altered cytotoxicity. Their cytotoxicity toward MDA‐MB‐231 cells is preserved or enhanced. At the highest assayed concentration, β‐HpH‐CholTrp produced the same cytotoxic effect against MDA‐MB‐231 cells as that reported for doxorubicin. Oppositely, the native ß‐HpH, significantly stabilizes MCF‐7 cells and their metastatic potential was enhanced.
Cholinium‐based ionic liquids with non‐polar amino acid anions affect seriously the secondary structure and thermal stability of a hemocyanin from Helix pomatia. However, in some cases these structural changes of the protein resulted to an increase of its selectivity and cytotoxycity toward breast cancer cells.
Angiogenesis is one of the key processes during development, wound healing and tumor formation. Prerequisite for its existence is the presence of endogenous electrical fields (EFs) generated by ...active ion transport across polarized epithelia and endothelia, and appearance of the transcellular potentials. During angiogenesis cellular factor as endothelial growth factor (VEGF), synthesis of adhesive proteins and membrane metalloproteinases (MMPs) govern the angiogenic response to different external stimuli as biomaterials interactions and/or exogenous EF. Gelatin-based hydrogels with elasticities comparable to human tissues have shown to influence cell behavior as well as cell attachment, protein synthesis, VEGF and MMP's production after the application of EF. Gelatin-based matrices with 3 (G10_LNCO3), 5 (G10_LNCO5), and 8 (G10_LNCO8) fold excess of isocyanate groups per mol of amine groups present in gelatin were used. Human umbilical endothelial cells (HUVEC) (Lonza Basel, Switzerland) and highly invasive breast cancer MDA-MB-231 cells (ATCC®HTB-26TM) were used. For an estimation of the amount of VEGF released from cells a commercially available VEGF ELISA (Thermo Fisher Scientific, Germany) kit was used. Fibronectin (FN) enzyme immunoassay (EIA) was used to analyze the secreted amount of FN by cells seeded on the materials. Secreted MMPs were analyzed by zymography. Gelatin-based hydrogels attracted HUVEC adhesion and diminished the adhesion of MDA-MB-231 cells. The applied direct current (DC) EF induced an almost 5-fold increase in VEGF production by HUVEC seeded on gelatin-based hydrogels, while in contrast, the applied EF decreased the production of VEGF by cancer cells. FN synthesis was elevated in HUVEC cells seeded on gelatin-based materials in comparison to FN synthesis by cancer cells. HUVEC seeded on gelatin hydrogels showed an expression mainly of MMP-2. The application of EF increased the production of MMP-2 in HUVEC seeded on gelatin materials. In contrast, for MDA-MB-231 the production of MMPs on gelatin materials was lower compared to control materials. With the application of EF the levels of MMP-9 decreased but MMP-2 expression raised significantly for gelatin materials. Overall, the results showed that studied gelatin materials suppressed attachment of cancerous cells, as well as suppressed their angiogenic potential revealed by decreased VEGF and MMP production. Thus, this study approved gelatin-based hydrogels with proper elasticity characteristics and different degradation behavior as useful matrices for use in vascular tissue regeneration or in restriction of tumor growth after tumor resection.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The biocompatibility of hybrid hydroxypropyl cellulose (HPC) hydrogels with different content of embedded silver nanoparticles (AgNPs) is revealed by testing the cytotoxicity and induction of cell ...death. The effect of cytotoxicity and cell death was studied on L929 fibroblasts by using MTT cytotoxicity assay, cell morphological observations and acridine orange/ethidium bromide (AO/EtBr) live cell staining. The results showed good biocompatibility of hydrogels containing AgNPs in the range 0.5-1.5 wt % Ag. Cells incubated with HPC hydrogels with the higher amount of AgNPs (2-2.5 wt % Ag) presented morphological changes corresponding to cell death and increased grade of cytotoxicity revealed by MTT assay. All these data suggest that AgNPs content in HPC materials exibits dose-dependent threshold over which the biocompatibility of the hydrogels is disturbed. Hybrid materials with low silver content - 0.5 wt % to 1.5 wt % Ag proved their biocompatibility and will be suitable candidates for biomedical applications.Key words: antibacterial materials, silver nanoparticles, biocompatibility, cytotoxicity, cell death
There is a need to create cell- and histocompatible implant materials, which might temporarily replace the mechanical function of a native tissue for regenerative therapies. To match the elastic ...behavior of the native tissue two different multiblock co-polymers were investigated: PDC,
consisting of poly(p-dioxanone) (PPDO)/poly(ε-caprolactone) (PCL), and PDD, based on PPDO/poly((adipinate-alt-1,4-butanediol)-co-(adipinate-alt-ethylene glycol)-co-adipinate-alt-diethylene glycol) (Diorez). PDC is capable of a shapememory
effect. Both multiblock co-polymers show an improved elasticity compared to materials applied in established vascular prosthesis. PDD is softer than PDC at 20°C, while PDC maintains its elasticity at 37°C. Thermodynamic characteristics indicate a more polar surface of PDD. Low cell
adhesion was found on surfaces with low molar free energy of hysteresis (ΔG) derived from contact angle measurements in wetting and dewetting mode and high cell adhesion on high-ΔG surfaces. An increasing content of PCL in PDC improved cell adhesion and spreading
of human umbilical vein endothelial cells. The prothrombotic potential of PDD is higher than PDC. Finally, it is concluded that PDC is a promising material for vascular tissue engineering because of its improved elastic properties, as well as balanced prothrombotic and anti-thrombotic properties
with endothelial cells.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
In the present study we aimed to evaluate the role of cytotoxicity of erufosine for eliciting changes in cytoskeleton organization and induction of apoptosis in Graffi myeloid tumour cells. The ...cytotoxicity of erufosine was revealed by MTT assay. The effect of erufosine on cytoskeleton and cell nuclei was evaluated by immunostaining for alpha-tubulin and F-actin, as well as by DAPI staining. We show that IC.sub.50 dose for EPC.sub.3 treatment of Graffi tumour cells was obtained at 20 microM. Fluorescent images showed existence of apoptosis at the same EPC.sub.3 concentration. The induction of apoptosis by EPC.sub.3 was accompanied by actin and tubulin reorganization. The obtained results revealed reorganization of actin cytoskeleton and induction of adhesive cell phenotype by erufosine treatment.Key words: erufosine, reorganization of cytoskeleton, apoptosis, Graffi tumour cells
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