Vitamin D increases the efficacy of cisplatin on bladder cancer cell lines.

BACKGROUND: 1,25(OH)2D3(Calcitriol), which is a broad regulatory molecule, plays a role in changing the efficacy of chemotherapeutic drugs. Cisplatin is one of a current standard chemotherapy regimen for bladder cancer. Increasing the effectiveness of the treatment and reducing the side effects to chemotherapeutics are of great importance in bladder cancer. We aimed to investigate the effect of the combination of cisplatin and calcitriol in order to create a possible advantage in treatment of bladder cancer. METHODS: T24, ECV-304 and HUVEC cell lines were treated with calcitriol and cisplatin individually and in combination. Dose determination and combination treatments of calcitriol and cisplatin were evaluated using the MTT assay for cytotoxicity analysis on the cells. Annexin V-PI staining method was used for apoptosis determination by flow cytometry. Also the P-gp expression levels were determined by flow cytometry. RESULTS: The combination treatment increased the anti-proliferative efficacy compared to the efficacy in cisplatin alone in T24 cells and reduced the cytotoxicity in the HUVEC healthy cells compared to cisplatin alone. Combination treatment achieved significantly higher apoptosis rate in T24 cells compared with the rates in treatment of cisplatin alone. However apoptosis decreased in HUVEC cell line. P-gp ratios were increased in HUVEC and decreased in T24 cells with combination treatment compared to the numbers in the control cells. The rate of apoptosis and P-gp levels showed no significant change in ECV-304 cells. CONCLUSION: Our study revealed that the combination of calcitriol and cisplatin allows the use of cisplatin at lower doses in T24 bladder cancer cell line.

Synthesis, structural, cytotoxic and pharmacokinetic evaluation of some thiosemicarbazone derivatives.

Iron(III) and nickel(II) complexes bearing a thiosemicarbazone framework were synthesized by a one-pot synthesis method. The structures were characterized by elemental analysis, IR, 1 H NMR, APCI Mass, conductivity, magnetic moment measurements. Molecular and crystal structures of the iron(III) complex were obtained from single-crystal X-ray diffraction. The findings showed that the metal atom adopts a slightly distorted square-pyramidal coordination, with the four donor atoms of the thiosemicarbazone ligand defining the basal plane and a chloride atom occupying the apical position. In the crystal lattice, the structure is stabilized by intermolecular O─H···O and C─H···O interactions. The cytotoxic activity was studied by MTT assay, the expression levels of cytochrome P450 (CYP) enzymes by Western blot, and the lipophilicity (LogP) by using the shake-flask method, another pharmacokinetic parameter. The findings showed that the IC50 values decreased with the decrease of the LogP values of the substances. Cytochrome P450 expression levels were found specific for each compound and each cell line. As a result, the pharmacokinetic properties of the newly synthesized thiosemicarbazone compounds are crucial for oral administration and provide us with clues for prospective in vivo studies.

Mechanical and Biocompatibility Properties of Calcium Phosphate Bioceramics Derived from Salmon Fish Bone Wastes.

Natural calcium phosphates derived from fish wastes are a promising material for biomedical application. However, their sintered ceramics are not fully characterized in terms of mechanical and biological properties. In this study, natural calcium phosphate was synthesized through a thermal calcination process from salmon fish bone wastes. The salmon-derived calcium phosphates (sCaP) were sintered at different temperatures to obtain natural calcium phosphate bioceramics and then were investigated in terms of their microstructure, mechanical properties and biocompatibility. In particular, this work is concerned with the effects of grain size on the relative density and microhardness of the sCaP bioceramics. Ca/P ratio of the sintered sCaP ranged from 1.73 to 1.52 when the sintering temperature was raised from 1000 to 1300 °C. The crystal phase of all the sCaP bioceramics obtained was biphasic and composed of hydroxyapatite (HA) and tricalcium phosphate (TCP). The density and microhardness of the sCaP bioceramics increased in the temperature interval 1000-1100 °C, while at temperatures higher than 1100 °C, these properties were not significantly altered. The highest compressive strength of 116 MPa was recorded for the samples sintered at 1100 °C. In vitro biocompatibility was also examined in the behavior of osteosarcoma (Saos-2) cells, indicating that the sCaP bioceramics had no cytotoxicity effect. Salmon-derived biphasic calcium phosphates (BCP) have the potential to contribute to the development of bone substituted materials.

Novel palladium (II) complexes with tetradentate thiosemicarbazones. Synthesis, characterization, in vitro cytotoxicity and xanthine oxidase inhibition.

In vitro cytotoxicity and xanthine oxidase inhibition capabilities were investigated for five palladium (II) chelate complexes. The palladium complexes were synthesized by starting from S-alkyl-thiosemicarbazones where the alkyl component is methyl, ethyl, propyl or butyl. The solid complexes are characterized by elemental analysis and spectroscopic techniques (UV-visible, IR and 1H NMR). In order to be able to verify the N2O2-type thiosemicarbazidato ligand (L2-) structure in the square planar geometry, complex 1 has been studied as a representative by using single crystal X-ray crystallography. The in vitro cytotoxic activity measurements were carried out in HepG2 and Hep3B hepatocellular carcinomas, HCT116 colorectal carcinoma, and 3 T3 mouse fibroblast cell lines. The palladium complexes exhibited notable cytotoxic activities in all cell lines at lower µM concentrations compared to the standard chemicals, cisplatin and allopurinol. IC50 values were determined between 0.42 ± 0.01 and 12.01 ± 0.37 µg/ml in examining the antixanthine oxidase abilities of the complexes. Two complexes with S-methyl group exhibited a high inhibition activity on the xanthine oxidase. The results indicated that these complexes could be used as active pharmaceutical ingredients.

Iron(III) and nickel(II) complexes of tetradentate thiosemicarbazones: Synthesis, structure, cytotoxicity, and lipophilicity.

Eighteen of the iron(III) and nickel(II) complexes with tetradentate thiosemicarbazidato ligands were synthesized and described, by analytical and spectroscopic methods. Two complexes as an example to the iron and nickel centered ones were crystallographically analyzed to confirm the molecular structures. Cytotoxic effects of the complexes on K562 chronic myeloid leukemia cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. For comparison, human umbilical vein endothelial cells (HUVECs) was used as a noncancerous cell line. While four of the iron(III) complexes exhibited the antileukemic effect with 50% inhibition of cell growth (IC50 ) values in the 3.4 to 6.9 µg/mL range on K562 cell line, the nickel(II) complexes showed no significant effect on both cell lines. The complexes Fe4, Fe5, and Fe6, bearing 4-methoxy substituent exhibited relatively high antiproliferative activity on both cell lines. Complex Fe3 with 3-methoxy and S-allyl groups exhibited a selectivity between K562 and HUVEC cells by IC50 values of 6.9 and >10 µg/mL, respectively. Lipophilicity, a key parameter for bioavailability and oral administration, was found in the range of -0.3 and +1.3 that desired for drug active ingredients. The results were discussed in the context of a structure-activity relationship.

Cellular interactions with bacterial cellulose: Polycaprolactone nanofibrous scaffolds produced by a portable electrohydrodynamic gun for point-of-need wound dressing.

Electrospun nanofibrous scaffolds are promising regenerative wound dressing options but have yet to be widely used in practice. The challenge is that nanofibre productions rely on bench-top apparatuses, and the delicate product integrity is hard to preserve before reaching the point of need. Timing is critically important to wound healing. The purpose of this investigation is to produce novel nanofibrous scaffolds using a portable, hand-held "gun", which enables production at the wound site in a time-dependent fashion, thereby preserving product integrity. We select bacterial cellulose, a natural hydrophilic biopolymer, and polycaprolactone, a synthetic hydrophobic polymer, to generate composite nanofibres that can tune the scaffold hydrophilicity, which strongly affects cell proliferation. Composite scaffolds made of 8 different ratios of bacterial cellulose and polycaprolactone were successfully electrospun. The morphological features and cell-scaffold interactions were analysed using scanning electron microscopy. The biocompatibility was studied using Saos-2 cell viability test. The scaffolds were found to show good biocompatibility and allow different proliferation rates that varied with the composition of the scaffolds. A nanofibrous dressing that can be accurately moulded and standardised via the portable technique is advantageous for wound healing in practicality and in its consistency through mass production.

Fabrication of naturel pumice/hydroxyapatite composite for biomedical engineering.

BACKGROUND: We evaluated the Bovine hydroxyapatite (BHA) structure. BHA powder was admixed with 5 and 10 wt% natural pumice (NP). Compression strength, Vickers micro hardness, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction studies were performed on the final NP-BHA composite products. The cells proliferation was investigated by MTT assay and SEM. Furthermore, the antimicrobial activity of NP-BHA samples was interrogated. RESULTS: Variances in the sintering temperature (for 5 wt% NP composites) between 1000 and 1300 °C, reveal about 700 % increase in the microhardness (~100 and 775 HV, respectively). Composites prepared at 1300 °C demonstrate the greatest compression strength with comparable result for 5 wt% NP content (87 MPa), which are significantly better than those for 10 wt% and those that do not include any NP (below 60 MPa, respectively). CONCLUSION: The results suggested the optimal parameters for the preparation of NP-BHA composites with increased mechanical properties and biocompatibility. Changes in micro-hardness and compression strength can be tailored by the tuning the NP concentration and sintering temperature. NP-BHA composites have demonstrated a remarkable potential for biomedical engineering applications such as bone graft and implant.

Effects of micro environmental factors on natural killer activity (NK) of beta thalassemia major patients.

The physiological mechanisms of decreased NK activity of ß-Thalassemia major (BTM) patients are unknown. To assess in vitro effects of mononuclear cells and their cytokine secretion on NK activity, we compared activator receptor levels and cytotoxic activity of purified NK cells and NK cells in mononuclear cells (MNC) pools. We collected cell supernatant from unincubated and incubated MNC with K562 cells and measured their secreted cytokines levels. CD16 was lower on the surface of NK cells in MNC pools from BTM patients compared to healthy volunteers. This inhibition does not appear when NK cells were purified. NKp30 levels in NK cells decreased both as purified cells and as part of a pool of MNC in BTM patients. After incubation of MNC pools with K562 target cells, we found that supernatant levels of IL10, TGFß1 and IL15 cytokines were also significantly higher in BTM patients compared to healthy volunteers.

DNA groove binder and significant cytotoxic activity on human colon cancer cells: Potential of a dimeric zinc (II) phthalocyanine derivative.

The interaction of a multi-component system consisting of benzene-1,4-diyldimethanimine-bridged dimeric zinc-phthalocyanine groups (4OMPCZ) with calf thymus DNA (ct-DNA) was investigated using UV-Vis absorption, fluorescence emission spectroscopy methods, and viscosity measurements. The binding constant, Kb, which is an important parameter to gain information about the binding mode, was found as 9.7 × 107 M-1 from the UV-Vis absorption studies. Another important spectrophotometric tool is competitive displacement assays with Ethidium bromide and Hoechst 33342. Through this experiment, a higher KSV value was obtained with Hoechst for the phthalocyanine derivative, 4OMPCZ, and the ct-DNA complex than with ethidium bromide. Additionally, molecular docking studies were conducted to calculate the theoretical binding constant and visualize the interactions of 4OMPCZ with a model DNA. According to docking results, although the interactions are mainly located in the major groove of the DNA helix, due to the wrapping, these interactions can also be extended to the minor groove of the DNA. Spectrophotometric, molecular docking, and viscosity studies revealed that the interaction of 4OMPCZ with DNA is likely to be via the major and minor grooves. The in vitro cytotoxic activity of 4OMPCZ was evaluated by MTT assay on human colon cancer cells (HT29) after 72 h of treatment. 4OMPCZ indicated significant cytotoxic activity when stimulated with UV light compared to the standard chemotherapy drugs, fluorouracil (5-FU), and cisplatin on HT29 colon cancer cells. The IC50 value of 4OMPCZ displayed considerably lower concentrations compared to the standard drugs, 5-FU, and cisplatin.

New thiosemicarbazone-based Zinc(II) complexes. In vitro cytotoxicity competing with cisplatin on malignant melanoma A375 cells and its relation to neuraminidase inhibition.

New thiosemicarbazone-based zinc(II) complexes were synthesized to study their cytotoxicity on A375 malignant melanoma cells. The complexes containing salicylidene (Zn1a), 3-methoxy-salicylidene (Zn1b) or 4-methoxy-salicylidene (Zn1c) moiety were characterized by analytical and spectroscopic methods. Anticancer potential of the complexes was determined by MTT test and HUVEC endothelial cells line was used to comprehend the effect on normal cells. Zn1b with an IC50 of 13 µM was found to be highly cytotoxic against A375 cancer cells, more effective than cisplatin (IC50: 37 µM). Zn1a and Zn1c did not have a negative effect on cell viability in the normal cells and gave the impression that they are more advantageous than cisplatin in this respect. Further, the ability of Zn1a-c to inhibit neuraminidase enzyme and its role in cytotoxicity was discussed. The test revealed that the Zn1b with 3-methoxy substituent exhibited higher inhibition activity against the neuraminidase than the Zn1a and Zn1c as analogical to the cytotoxicity results. In neuraminidase inhibition, IC50 values of Zn1b and Zn1c were 14 and 66 µM, respectively. These concentrations were very close to the cytotoxicity concentrations for Zn1b and Zn1c. The findings may indicate the role of neuraminidase enzyme inhibition in cell death for Zn1b and Zn1c.

New oxovanadium(IV) complexes overcame drug resistance and increased in vitro cytotoxicity by an apoptotic pathway in breast cancer cells.

In order to examine the anticancer potential of oxovanadium(IV) complexes with thiosemicarbazone, two new complexes were prepared starting from 2-thenoyltrifluoroacetone-S-methylthiosemicarbazone. The complexes with tetradentate thiosemicarbazone ligand were characterized by elemental analysis, IR, ESI MS, and single-crystal X-ray diffraction analysis. Cytotoxicity on breast cancer cells, MDA-MB-231 and MCF-7, was determined by MTT assay. Cisplatin was positive control and the results were compared with those of the normal cells, HUVEC and 3T3. The complexes exhibited greater activity on cancer cells than cisplatin, but they were cytotoxic at several times higher concentrations in the healthy cells. In our study, the presence of thiophene and fluoro groups in the oxovanadium(IV) complexes with thiosemicarbazone increased greatly the cytotoxic activity of the complexes on breast cancer cells. Moreover, the complexes induced apoptosis-mediated cell death and also reduced the expression of MDR-1 or P-glycoprotein and ABCG2. As a result, the findings indicated that the complexes have selective cytotoxicity on breast cancer cells and can overcome multidrug resistance. These properties of the complexes make it possible to be a potential anticancer drug candidate for breast cancer treatment.

The evaluation of anticancer activity by synthesizing 5FU loaded albumin nanoparticles by exposure to UV light.

In this study, as a new synthesis method, UV light was employed as a type of cross-linking agent to control drug storage and to produce nanoparticles of different sizes and to stabilize the nanoparticles for the first time. We showed that the exposure time of the 5FU albumin solution to UV light produces differences in the size and characterization of the nanoparticles and also produces different cytotoxic effects on MCF-7 breast cancer cells. While the 5FU-A1 nanoparticles we synthesized with 1 h UV storage were approximately 43 nm, the 5FU-A2 nanoparticles we synthesized with UV storage for 3 h increased to an average of 300 nm. 5FU-A1 (IC50 value: 2.5 µg/mL) was approximately 16 times more cytotoxic than free 5FU (IC50 value 39.39 µg/mL) on MCF-7 cancer cells. Moreover, when normal HUVEC cells are treated with 5FU-A1 at a concentration of 2.5 µg/mL, more than 80% of these normal cells remain viable. In addition, we examined the rate of early-to-late apoptosis and necrosis in MCF-7 cancer cells using the Annexin V/PI flow cytometry assay. According to our results, 5FU-A1 promoted the apoptosis pathway. Finally, we examined P-gp activity with MDR1/ABCB1 antibody by flow cytometry and Rhodamine123 with fluorescent dye.

Selective Cytotoxic Effects of 5-Trifluoromethoxy-1H-indole-2,3-dione 3-Thiosemicarbazone Derivatives on Lymphoid-originated Cells.

AIM: The present study aims to identify the anticancer effect of novel 1H-indole-2,3-dione 3- thiosemicarbazone derivatives. These compounds could be promising anticancer agents in leukemia treatment. BACKGROUND: Conventional chemotherapeutic agents accumulate in both normal and tumor cells due to nonspecificity. For effective cancer treatment, new drugs need to be developed to make chemotherapeutics selective for cancer cells. The ultimate goal of cancer treatment is to reduce systemic toxicity and improve the quality of life. METHODS: In this study, the anticancer effects of 5-trifluoromethoxy-1H-indole-2,3-dione 3-thiosemicarbazone derivatives (A-L) were investigated in chronic myelogenous leukemia K562, Burkitt's lymphoma P3HR1, acute promyelocytic leukemia HL60 cells, and vincristine-resistant sublines of K562 and P3HR1 cells. Additionally, the compounds were tested on lymphoid-derived cells from ALL patients. In order to investigate the particular mechanism of death caused by the cytotoxic effects of the compounds, immunohistochemical caspase 3 staining was performed in P3HR1 cells, and the resulting apoptotic activities were demonstrated. RESULTS: All tested compounds have been found to have cytotoxic effects against lymphoma cells at submicromolar concentrations (IC50= 0.89-1.80 µM). Most compounds show significant selectivity for the P3HR1 and P3HR1 Vin resistance. The most effective and selective compound is 4-bromophenyl substituted compound I (IC50=0.96 and 0.89 µM). Cyclohexyl and benzyl substituted compounds D and E have also been found to have cytotoxic effects against K562 cell lines (IC50=2.38 µM), while the allyl substituted compound C is effective on all cell lines (IC50=1.13-2.21 µM). 4-Fluorophenyl substituted F compound has been observed to be effective on all cells (IC50=1.00-2.41 µM) except K562 cell. Compound C is the only compound that shows inhibition of HL-60 cells (IC50= 1.13 µM). Additionally, all compounds exhibited cytotoxic effects on lymphoidderived cells at 1µM concentration. These results are in accordance with the results obtained in lymphoma cells. CONCLUSION: All compounds tested have submicromolar concentrations of cytotoxic effects on cells. These compounds hold potential for use in future treatments of leukemia.

Evaluation of anticancer effects of carboplatin-gelatin nanoparticles in different sizes synthesized with newly self-assembly method by exposure to IR light.

Carboplatin (CP), a platinum analog, is one of the most widely used chemotherapeutic agents in the treatment of colorectal cancer. Although platinum-based drugs are quite effective in anticancer treatments, their use in a wide spectrum and effective treatment possibilities are limited due to their systemic side effects and drug resistance development. In recent years, studies have focused on increasing the therapeutic efficacy of platinum-based drugs with drug delivery systems. Gelatin, a protein, obtained by the hydrolysis of collagen, is a biocompatible and biodegradable material that can be used in nano drug delivery systems. In this study, CP-loaded gelatin-based NPs (CP-NPs) were exposed to IR light in different temperatures at 30, 35, 40, 45, and 50 °C and characterized by FESEM-EDX, FTIR, UV-Vis, DLS. Accordingly, we synthesized gelatin-based CP-NPs of different sizes between 10-290 nm by exposure to IR. We found that CP-NPs-50, 16 nm nano-sized, obtained at 50 °C had the most cytotoxicity and was 2.2 times more effective than the free drug in HCT 116 colon cancer cells. Moreover, we showed that the cytotoxicity of CP-NPs-50 in normal HUVEC cells was lower. Additionally, we demonstrated that CP-NPs enhanced apoptotic activity while not developing MDR1-related resistance in colon cancer cells. In this study, for the first time drug loaded gelatin-based nanoparticles were synthesized in different sizes with a newly self-assembly method by exposing them to infrared light at different temperatures and their anticancer effects were evaluated subsequently.

Poly(L-lactic acid)/poly(ethylene oxide) based composite electrospun fibers loaded with magnesium-aluminum layered double hydroxide nanoparticles.

Two types of MgAl layered double hydroxide nanoparticles, MgAl LDH, at Mg:Al ratio of 2:1 and 3:1were prepared and used as inorganic fillers to improve the mechanical properties of poly(lactic acid)/poly(ethylene oxide) (PLA/PEO) electrospun composite fibers. Their detailed structural characterization was performed using X-ray diffraction (XRD) and transmission electron spectroscopy (TEM) techniques. Spectroscopic, thermal, mechanical, and morphological properties of the electrospun composite fibers, and cell proliferation on their surface, were examined. XRD and TEM analyses showed that the LDH nanoparticles were 50 nm in size and the Mg:Al ratio did not affect the average spacing between crystal layers. Fourier transform infrared (FTIR) and thermal analyses (TA) revealed the compatibility of the filler and the polymer matrix. The nanoparticles considerably improved the mechanical properties of the electrospun mats. The tensile strength and elongation at break values of the composite samples increased from 0.22 MPA to 0.40 MPa and 12.2 % to 45.66 %, respectively, resulting from the interaction between LDH and the polymer matrix. Scanning electron microscopy (SEM) and MTT analyses demonstrated that the electrospun composite fibers supported the SaOS-2 cells attachment and proliferation on the fiber surfaces, along with their suitable cytocompatibility.

Spectrochemical and biochemical assay comparison study of the healing effect of the Aloe vera and Hypericum perforatum loaded nanofiber dressings on diabetic wound.

Diabetic wounds have a slow healing process and easy to be infected. In addition to current drug treatments, supportive approaches are needed for diabetic wound treatment. In this study, we aimed to load Aloe Vera (AV) and Hypericum perforatum oil (HPO) with PCL/Ge (Poly (ɛ-caprolactone)/Gelatine) polymeric biodegradable by electrospinning method into nanofiber dressings on an experimental diabetic wound model to compare the diabetic wound healing effect. Changes in the amount and chemical structure of phospholipids, proteins, and lipids were investigated in the blood and serum samples of the animals using Fourier transform infrared (FTIR) analysis. To evaluate biological events associated with the wound repair process in inflammatory phase we used oxidant and antioxidant status to determine the healing status of wounds such as Total antioxidant status (TAS), Total oxidant level (TOS) and tumor necrosis factor alpha (TNF-α) levels. TOS level increased in DM groups and decreased in the AV and HPO group. Oxidative stress index decreased and TNF-α level increased in the HPO group. FTIR spectra showed changes in the phospholipids, proteins, and carbon chain of lipids in the whole blood as well as serum of DM rats. FTIR spectra combined with Principal component analysis (PCA) showed, that treated DM rats by AV and HPO caused return chemical structure of blood and serum to this observed in control group. Higher similarity with control group for HPO rats was observed. HPO is better than AV in the alternative for healing on diabetic wound. Thus, we have demonstrated that IR spectroscopy and multivariate data analysis and biochemical assays are consistent and correlative with each other.

Development and In Vitro Evaluation of Biocompatible PLA-Based Trilayer Nanofibrous Membranes for the Delivery of Nanoceria: A Novel Approach for Diabetic Wound Healing.

The attempts to explore and optimize the efficiency of diabetic wound healing's promotors are still in progress. Incorporation of cerium oxide nanoparticles (nCeO2) in appropriate nanofibers (NFs) can prolong and maximize their promoting effect for the healing of diabetic wounds, through their sustained releases, as well as the nanofibers role in mimicking of the extra cellular matrix (ECM). The as-prepared nCeO2 were analyzed by using UV-Vis spectroscopy, XRD, SEM-EDX, TEM and FTIR, where TEM and SEM images of both aqueous suspension and powder showed spherical/ovoid-shaped particles. Biodegradable trilayer NFs with cytobiocompatibility were developed to sandwich nCeO2 in PVA NFs as a middle layer where PLA NFs were electrospun as outer bilayer. The nCeO2-loaded trilayer NFs were characterized by SEM, XRD, FTIR and DSC. A two-stage release behavior was observed when the nanoceria was released from the trilayer-based nanofibers; an initial burst release took place, and then it was followed by a sustained release pattern. The mouse embryo fibroblasts, i.e., 3T3 cells, were seeded over the nCeO2-loaded NFs mats to investigate their cyto-biocompatibility. The presence and sustained release of nCeO2 efficiently enhance the adhesion, growth and proliferation of the fibroblasts' populations. Moreover, the incorporation of nCeO2 with a higher amount into the designed trilayer NFs demonstrated a significant improvement in morphological, mechanical, thermal and cyto-biocompatibility properties than lower doses. Overall, the obtained results suggest that designated trilayer nanofibrous membranes would offer a specific approach for the treatment of diabetic wounds through an effective controlled release of nCeO2.

Cytotoxic activities of new iron(III) and nickel(II) chelates of some S-methyl-thiosemicarbazones on K562 and ECV304 cells.

The S-methyl-thiosemicarbazones of the 2-hydroxy-R-benzaldehyde (R = H, 3-OH 3-OCH(3) or 4-OCH(3)) reacted with the corresponding aldehydes in the presence of FeCl(3) and NiCl(2). New ONNO chelates of iron(III) and nickel(II) with hydroxy- or methoxy-substituted N(1),N(4)-diarylidene-S-methyl-thiosemicarbazones were characterized by means of elemental analysis, conductivity and magnetic measurements, UV-Vis, IR and (1)H-NMR spectroscopies. Cytotoxic activities of the compounds were determined using K562 chronic myeloid leukemia and ECV304 human endothelial cell lines by MTT assay. It was determined that monochloro N(1)-4-methoxysalicylidene-N(4)-4-methoxysalicylidene-S-methyl-thiosemicarbazidato-iron(III) complex showed selective anti-leukemic effects in K562 cells while has no effect in ECV304 cells in the 0.53 microg/ml (IC(50)) concentrations. Also, some methoxy-substituted nickel(II) chelates exhibit high cytotoxic activity against both of these cell lines in low concentrations. Cytotoxicity data were evaluated depending on cell lines origin and position of the substituents on aromatic rings.

Preparation of collagen modified photopolymers: a new type of biodegradable gel for cell growth.

In this study a new branched methacrylated poly(propylene glycol-co-lactic acid) (PPG-PLA-IEM) and methacrylated cellulose acetate butyrate resin (CAB-IEM) were synthesized. Hydrogels with various amounts of PPG-PLA-IEM and CAB-IEM (25, 50 and 75 wt% IEM modified) were prepared by photopolymerization. Collagen tethered PEG-monoacrylate (PEGMA-collagen) was prepared and introduced as a bioactive moiety to modify the hydrogel in order to enhance cell affinity. In vitro attachment and growth of 3T3 mouse fibroblasts and human umbilical vein endothelial cells (HUVEC) on the hydrogels with and without collagen were also investigated. It was observed that, the collagen improves the cell adhesion onto the hydrogel surface. With the increasing amount of collagen, cell viability increased by 28% for ECV304 (P < 0.05) and 30% for 3T3 (P < 0.05).

Comparative Study on the Anticancer Drug Potential of a Lectin Purified from Aloe Vera and Aloe-Emodin.

BACKGROUND: The effect of Aloctin, a lectin purified from Aloe vera leaves, and aloe emodin an anthraquinone glycoside purified from the leaves of the same plant, on several cancer cell lines was investigated. METHODS: Aloctin was isolated from A. vera leaf skin by ammonium sulphate precipitation and CNBr-Sepharose 4B-ovalbumin affinity chromatography. Specific new ligands for Aloctin were detected as fetuin and avidin by hemagglutination inhibition tests. The cytotoxic effect of Aloctin and aloe emodin on various human cancer cell lines was tested using MTT assay. Imatinib was tested as standard positive control. The mechanism underlying was tested by the Annexin V-FITC/PI test, with flow cytometry. RESULTS: The most sensitive cells to Aloctin and aloe emodin treatment, were identified as AGS human gastric adenocarcinoma cells. The effect was concentration dependent. It was shown that this effect does not occur by apoptosis or necrosis. In Aloctin-imatinib combinations studies, Aloctin significantly increased the cytotoxic effect of imatinib in a dose-dependent manner. It is expected that the results of this study will reveal important findings for the future use of A. vera lectin as well as aloe emodin in cancer research and contribution to lectin biochemistry.
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