Potential Advantages of Idarubicin-Loaded Trastuzumab-Coated Liposomes for Combating Head and Neck Squamous Cancer Cells.

OBJECTIVE: Head and neck squamous cell carcinoma (HNSCC) with a high mortality rate is among the most common types of cancer in the world. Human epidermal growth factor receptor 2 (HER2) is expressed higher than normal level in the most HNSCC tumors, making them resistant to chemotherapy and radiotherapy. Therefore, HER2 has been introduced as a suitable target for anticancer drugs. The aim of this study is to examine the efficacy of a treatment protocol involving targeted delivery of idarubicin encapsulated in trastuzumab-decorated liposomes to HNSCC cells. MATERIALS AND METHODS: In the current experimental study, efficacies of idarubicin, prepared liposomal idarubicin, and constructed immunoliposomal idarubicin (trastuzumab-decorated) were investigated in killing HN5 cells, a HER2- overexpressing HNSCC-originating cell line. Liposomal content of idarubicin and trastuzumab were qualified by UVVisible spectroscopy and preparations were characterized for shape and size by atomic force microscopy (AFM) and dynamic light scattering (DLS). To clarify role of the missing parts of the available crystal structure (PDB ID: 1n8z) within trastuzumab-HER2 interactions, we used a 40 ns molecular dynamic simulation approach. RESULTS: Based on the obtained results, liposomal idarubicin showed higher toxicity of the encapsulated drug on HN5 cells compared to the traditional free drug formulations. The immunoliposomal form of idarubicin was more effective than the liposomal formulation, in killing of HN5 cells. In addition, simulation of interactions between trastuzumab and HER2 revealed that the missing parts (in the crystal structure) of HER2 have critical interaction with trastuzumab, through salt-bridges and hydrogen bonds. CONCLUSION: It seems that the prepared immunoliposomes could attach more efficiently to HER2 overexpressing cells, which consequently leads to increasing cellular uptake of idarubicin through a receptor-mediated endocytosis mechanism. Moreover, simulation of the interaction between HER2 and trastuzumab suggested considerable possibilities for increasing trastuzumab affinity to HER2.

Simulation and practical investigation of carbonic anhydrase stability in an industrial solvent system of methyl diethanolamine for carbon dioxide capture.

Carbonic anhydrase owing to its potential as an industrial biocatalyst for carbon dioxide sequestration from flue gas has attracted considerable attention in solving global warming problems. A large body of research has been conducted to increase the thermal stability of carbonic anhydrase from different sources against the harsh operational conditions of CO2 capture systems. In contrast to cost-intensive protein engineering methods, solvation with aqueous-organic binary mixtures offers a convenient and economical alternative strategy for retention of protein structure and stability. This study aimed to examine the stabilizing effect of methyl diethanolamine (MDEA) as a component of an aqueous-organic solvent mixture on human carbonic anhydrase II (HCA II) at extreme temperatures. Computational and also spectroscopic examinations were employed for tracking conformational changes and stability evaluation of HCA II in 50:50 (vol %) water: MDEA binary mixture at high temperature. Molecular dynamic (MD) simulation studies predicted the high thermal stability of HCA II in the presence of MDEA. UV absorbance spectra confirmed the thermo-stabilizing effect of the binary solvent mixture on HCA II. While the enzymatic activity of HCA II at 25 °C in the presence of 10, 25, and 50 (vol%) of MDEA was substantially increased, no obvious effect on retention of HCA II activity in the water-MDEA binary solvent mixture at 85 °C was seen. It is shown that the solvation of HCA II in the presence of MDEA could result in the prevention of aggregate formation in high temperatures but not functional stability.Communicated by Ramaswamy H. Sarma.

Rational design engineering of a more thermostable Sulfurihydrogenibium yellowstonense carbonic anhydrase for potential application in carbon dioxide capture technologies.

Implementing hyperthermostable carbonic anhydrases into CO2 capture and storage technologies in order to increase the rate of CO2 absorption from the industrial flue gases is of great importance from technical and economical points of view. The present study employed a combination of in silico tools to further improve thermostability of a known thermostable carbonic anhydrase from Sulfurihydrogenibium yellowstonense. Experimental results showed that our rationally engineered K100G mutant not only retained the overall structure and catalytic efficiency but also showed a 3 °C increase in the melting temperature and a two-fold improvement in the enzyme half-life at 85 °C. Based on the molecular dynamics simulation results, rearrangement of salt bridges and hydrogen interactions network causes a reduction in local flexibility of the K100G variant. In conclusion, our study demonstrated that thermostability can be improved through imposing local structural rigidity by engineering a single-point mutation on the surface of the enzyme.

Potential protective effects of chrysin against immunotoxicity induced by diazinon.

Acute intoxication with diazinon (DZN) as a pesticide causes mortality and morbidity annually. This study shows the impact of sub-acute toxicity of DZN 20 mg/kg and the protective activities of chrysin (CH) as a flavone under the flavonoids family (12.5, 25 and 50 mg/kg) were assessed on BALB/c mouse immune system. The changes in morphological and functional properties of the immune system on thymus, spleen and liver histopathology, sub-populations of T lymphocytes, cytokines levels, transcription factors, complement function, phagocytosis, specific and total antibody productions were considered. The histopathological effects of DZN on the spleen and thymus were not significant, but the liver was damaged remarkably. In the presence of CH, the toxic effect of DZN is suppressed. DZN significantly decreased the number of whole blood TCD4+, TCD8+ and NK cells and suppressed the phagocytosis, delayed-type hypersensitivity (DTH) responses to sheep red blood cell (SRBC). Furthermore, it suppressed specific anti-SRBC-Ab, total IgG and IgM production, T-bet expression, and IFN-γ production. In contrast, DZN did not significantly affect complement function and the number of NK cells, TCD4+ and TCD8+ splenocytes. However, it potentiated the expression of GATA-3, ROR-γt and FOXP3 gene expression and consequently produced IL-4, IL-10, IL-17 and TGF-ß in whole blood. CH not only significantly increased the variables mentioned above at 12.5, 25 and 50 mg/kg but also could overcome the toxic effects of DZN on whole blood lymphocyte sub-populations and specific and total Ab production in 25 and 50 mg/kg concentrations, phagocytosis and DTH responses in 50 mg/kg, and modulation of the transcription factors and cytokine production, mainly in 25 and 50 mg/kg. In conclusion, DZN in sub-acute doses could remarkably deteriorate immune responses. However, CH can overcome the toxic effects of DZN on the immune components and functions of the immune system.

Combinatorial in silico and in vivo evaluation of immune response elicitation by the affibody ZHER2.

Due to the high affinity for binding to target molecules and also other unique attributes, affibodies have a great potential to be used in immunotherapeutic and diagnostic approaches. However, the possibility of undesirable immune response is still a great concern. In the current study, we investigated the possible antigenicity, allergenicity and cytotoxicity of the HER2-targeting affibody ZHER2. The binding affinity of potential epitopes of the affibody to murine major histocompatibility complex (MHC) molecules was investigated by immunoinformatics tools and docking approaches. The possible interaction of ZHER2 with human leukocyte antigens HLA-DP, HLA-DM, HLA-DQ and HLA-DR was also studied by protein-protein docking. Additionally, the synthesized affibody gene was expressed and the protein was purified for boosted immunization of Balb/c mice. Induced secretion of IFN-γ, IL-2, IL-4 and IL-10, and total serum IgG were assessed in the immunized mice. Furthermore, MTT cell viability test was performed to evaluate the cytotoxicity of ZHER2 in splenocytes of the treated mice. In silico analyses showed the possible induction of the immune response by ZHER2. While the affibody could elicit the secretion of cellular immune cytokines, it could not induce a significant humoral response in the treated mice and did not show any cytotoxic effects on the exposed splenocytes. These findings explain the practicability of ZHER2 for therapeutic and in vivo diagnostic usages, though its ubiquitous application may need more studies.

Evaluation of TNF Family Gene Expression under the Influence of Single-Walled and Multi-Walled Carboxylated Carbon Nanotubes in Jurkat Cell Line and Rat.

BACKGROUND: Nanomaterials, e.g.carbon nanotubes (CNTs), have broad usage in medicine for diagnosis, treatment, and drug delivery. Prior to the widespread use of CNTs, any potential toxicity issues must be considered. Apoptosis is an important issue in toxicological studies, and tumor necrosis factor (TNF) family members execute crucial roles in apoptosis and inflammation. We examined the survival of Jurkat cells under the influence of single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) as well as their impacts on the mRNA levels of TNF family transcripts in Jurkat cells and rats. OBJECTIVE: To evaluate the toxicity or safety of a specific concentration and form of CNT on the expression of one of the gene families of the apoptotic pathway. MATERIALS AND METHODS: Jurkat cells were exposed to SWCNTs and MWCNTs in carboxylated form (SWCNTS-COOH and MWCNTs-COOH). MTT assay assessed the cell survival, and using qRT-PCR, the expression levels of TNF, CD40LG, TNFSF10, TNFSF8, CD40, TNFRSF10A, TNFRSF10B, TNFRSF11B, TNFRSF1A, TNFRSF21, TNFRSF25, and TNFRSF9 were examined. The housekeeping genes ß-actin and glyceraldehyde 3-phosphate dehydrogenase was utilized for normalization. We also evaluated the expression levels of TNF and TNFRSF10A in rats in vivo 30 and 60 days after being injected with CNTs. RESULTS: After 72 h of carboxylated CNTs at 100 µg. mL-1, no significant change was observed in the survival rate of treated Jurkat cells. The expression of two genes (TNF and TNFRSF10A) changed significantly. Examining the expression profiles of these two genes in rats demonstrated an insignificant change in the expression of any of these genes after 30 and 60 days. The qRT-PCR analysis exhibited the elevated levels of TNF and TNFRSF10A mRNA in the CNT-treated cells, while expression of other TNF family members did not significantly differ from control (untreated) Jurkat cells. There was also no significant change in the gene expression levels of TNF and TNFRSF10A in CNT-treated rats after 30 and 60 days. CONCLUSIONS: Administration of SWCNTs-COOH and MWCNTs-COOH could result in the up-regulation of TNF and TNFRSF10A but did not initiate apoptosis in Jurkat cells. Carboxylated SWCNTs showed more potent activity than MWCNTs in activating TNF gene expression and probably trigger cell death through external apoptotic pathways.

3D structure prediction, dynamic investigation and rational construction of an epitope-masked thermostable bovine hyaluronidase.

Hyaluronidase (HAase) from bovine testes (BTH) has long been used in broad pharmaceutical areas, while it is associated with drawbacks in aspects of solubility, immunogenicity and pharmacokinetics. These issues can be addressed by gaining structural insights and designing rational modifications to the enzyme structure, as proposed in this study. A 3D structural model was built for HAase and underwent 40 ns of molecular dynamic simulation to examine its thermostability under normal, melting, and extreme conditions. The enzyme activity of BTH was measured against temperature and pH by kinetic assays. The interaction of bovine HAase with HA and chondroitin was defined by molecular docking. Furthermore, immunogenic properties of the enzyme were explored by immunoinformatics. Thermal effects on bovine HAase structural model and the HAase interactions with its substrates were described. We identified some B- and T-cell epitopes and showed that the protein could be recognized by human immune receptor molecules. Epitope masking by adding polyethylene glycol (PEG) to amine groups of residues presenting on the surface of the protein structure was adopted as a surface modification to enhance pharmacological properties of BTH. Assays showed that PEGylated BTH had higher thermostability and similar activity compared to the native enzyme.

Comparative evaluation of the protective effects of oral administration of auraptene and umbelliprenin against CFA-induced chronic inflammation with polyarthritis in rats.

This study aimed to evaluate the anti-inflammatory effect of Auraptene (AUR) and Umbelliprenin (UMB) in a rat model of rheumatoid arthritis (RA) induced by using complete Freund's adjuvant (CFA). Paw swelling of adjuvant arthritis rats measured at various times after CFA injection. Over 15 days of RA induction, mediator/cytokine-mediated processes involved in managing the regulation and resolving RA's inflammation were also quantified with ELISA. Histopathological changes were also assessed under a microscope 15 days after the CFA injection. AUR at all doses and UMB administration only at a 16 mM /kg administration dose significantly reduced CFA-induced paw edema level compared to the control group. UMB (64 and 32 mM) and AUR (64, 32, and 16 mM) could reduce the PGE2 (p < .0001-.01) and NO (p < .0001-.05) levels in the treatment groups compared to the negative control group. However, these compounds showed no significant effect on the TNF-α, IFN-γ, TGF-ß, IL-4, and IL-10 levels than the control group (p > .05). Unlike indomethacin and prednisolone, treatment of rats with AUR (16, 32, and 64 mM/kg) and UMB (16 and 32 mM/kg) reduced the level of IL-2 (p < .0001). In all treatment groups, the serum level of IL-17 was significantly reduced compared to the CFA group (p < .001-0.05). We suggested AUR and UMB could diminish inflammation by reducing the serum level of IL-17 and could be considered a proper alternative in the treatment of IL-17 related inflammatory diseases such as rheumatoid arthritis. Given that AUR and UMB apply their anti-inflammatory effects by changing distinct cytokine release/inhibition patterns, their potential application in diverse inflammatory diseases seems different.

Improvement of Targeted Chemotherapy of HER2-positive Ovarian Malignant Cell Line by ZHER2-Idarubicin Conjugate: An in vitro Study.

BACKGROUND & OBJECTIVE: Overexpression of human epidermal growth factor receptor 2 (HER2) causes cell transformation and development of various types of malignancies. Idarubicin is an effective anti-neoplastic drug but its specific delivery to the targeted cells is still a great challenge. Affibody as a cost-effective peptide molecule with low molecular weight has a high affinity for HER2 receptors. Breast and ovarian cancers as wide speared types of malignancies are associated with high expression of HER2. In the current study, we assessed the cytotoxic effects of idarubicin-ZHER2 affibody conjugate on the positive-HER2 cancer cell lines. METHODS: The cytotoxic effects of constructed idarubicin-ZHER2 affibody conjugate on the SK-BR-3, SK-OV-3, and MCF-7 cells with various levels of HER2 expression were evaluated by MTT assay following 48 hours of incubation. RESULTS: Idarubicin showed a potent and dose-dependent cytotoxic effect against all treated cell lines while the SK-OV-3 cells were significantly more sensitive. The dimeric form of the ZHER2 affibody molecule showed a mild effect on the cell viability of all treated cells at its optimum concentration. The constructed Idarubicin-ZHER2 affibody conjugate decreased the viability of SK-OV-3 cells at its optimal concentration, more efficiently and specifically than other treated cells. CONCLUSION: The ZHER2-affibody conjugate of idarubicin has a more specific cytotoxic effect compared with idarubicin alone against HER2-overexpressing ovarian cancerous cells. It appears the ZHER2-affibody conjugate of idarubicin has great potential to be implicated as an innovative anti-cancer agent in future clinical trials in patients with HER2-overexpressing ovarian cancer.

Induction of caspase-2 gene expression in carboxyl-functionalized carbon nanotube-treated human T-cell leukemia (Jurkat) cell line.

Carbon nanotubes (CNTs) have great potential as novel diagnostic or therapeutic tools in biomedicine but, cellular toxicity must be well considered before widespread application of CNTs. Many chemical agents exert their toxicity through apoptotic pathways by induction of caspase biomolecules. In the current study, effects of carboxyl-functionalized single-walled (SW) and multi-walled (MW) CNTs at a single dose of 100 µg ml-1 on the survival of Jurkat cells were examined using MTT assay. Additionally, the impacts of carboxylated CNTs on the gene expression levels of selected caspases were investigated. Jurkat cells were exposed to CNTs (100 µg ml-1 for 72 h) and then expression levels of selected caspase genes (Cas) were evaluated by qRT-PCR analysis. Housekeeping genes, ß-actin, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH), were used as normalization controls. The results showed only a mild decrease in the viability of Jurkat cells treated with carboxylated MWCNT. The results of qRT-PCR analysis revealed the elevated level of Cas2 mRNA in the cells treated with carboxylated MWCNT (6.08-fold) and carboxylated SWCNT (1.20-fold). The expression levels of Cas4, Cas6, Cas8, and Cas10 genes were increased not significantly compared to the control untreated cells. Our findings suggested that exposure to carboxyl-functionalized CNTs could be resulted in up-regulation of the Cas2 gene and not initiator Cas8 and Cas10 genes. In addition, it seems that carboxylated MWCNT was more potent than SWCNT in activation of Cas2 gene expression and triggering cell death signal in a manner different from intrinsic or extrinsic apoptosis pathways.

Cytotoxicity evaluation of curcumin-loaded affibody-decorated liposomes against breast cancerous cell lines.

Curcumin is known as an effective anticancer herbal medicine but unfortunately, its bioavailability is poor which necessitate efforts for developing more efficient and specific delivery systems. Human epidermal growth factor receptor 2 (HER 2) due to its overexpression in various types of cancers, is demonstrated to be a good candidate as a target for anticancer therapy. In this study, cytotoxicity of curcumin encapsulated in ZHER2:342 Affibody-decorated liposome was investigated against SKBR3 and MCF-7 cancerous cell lines. Curcumin-containing liposomes were prepared from soybeans lecetin and cholesterol by thin-film hydration method. Affibody ZHER2:342 molecules via C-terminal cysteine residue were conjugated covalently to the prepared liposomes. Particle size analysis was performed using atomic force microscopy (AFM) and dynamic light scattering (DLS). Curcumin loading was measured using UV-Vis spectrophotometry and cytotoxic activity of curcumin formulations against cancerous cell lines was investigated by MTT assay. Induction of apoptosis was investigated using flow cytometry through Annexin V staining. Particle analysis showed the formation of spherical liposomes with a mean diameter of about 150 nm. Cytotoxic activity of curcumin was improved by its encapsulation in both liposomes and affibody-decorated liposomes. The Annexin V staining indicated the induction of apoptosis by affibody-decorated liposomes in both MCF-7 and SKBR3 cells. Decoration of curcumin-loaded liposomes with affibody ZHER2:342 may improve curcumin apoptotic function independently of HER2 expression level.

Specific targeting of HER2-positive human breast carcinoma SK-BR-3 cells by amygdaline-ZHER2 affibody conjugate.

Amygdalin induces apoptotic death in several carcinoma cells. Affibody is an engineered protein with a high affinity for human epidermal receptor 2 (HER2). We assessed the cytotoxic effects of the amygdalin-ZHER2 affibody conjugate on two breast carcinoma cell lines. The ZHER2 affibody gene was synthesized and transferred into E. coli BL21 as an expression host. After purification, the ZHER2 affibody was conjugated to amygdalin. The cytotoxic effects of amygdalin and its ZHER2 affibody conjugate on the SK-BR-3, with overexpression of HER2, and MCF-7 cells were evaluated by MTT assay. The effects of amygdalin and its conjugate on apoptotic death and expression of pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins were measured. Amygdalin individually showed a potent cytotoxic effect against both MCF-7 (IC50 = 14.2 mg ml-1) and SK-BR-3 cells (IC50 = 13.7 mg ml-1). However, the amygdalin-ZHER2 affibody conjugate had a more cytotoxic effect on SK-BR-3 (IC50 = 8.27 mg ml-1) than MCF-7 cells (IC50 = 19.8 mg ml-1). Amygdalin had a significant apoptotic effect on both cell lines and the effect of its conjugate on SK-BR-3 cells was significantly more potent than MCF-7 cells. Amygdalin increased Bax and decreased Bcl-2 expression in both cell lines. However, the effect of its conjugate on the Bax and Bcl-2 expression in SK-BR-3 was more potent than MCF-7 cells. In conclusion, the amygdalin-ZHER2 affibody conjugate may be considered as a valuable candidate for specific treatment of breast cancer patients with overexpression of HER2. However, further in vivo studies are required to explain the antitumoral effects of constructed amygdalin-ZHER2 affibody conjugate.

In vitro and in silico anticancer activity of amygdalin on the SK-BR-3 human breast cancer cell line.

In spite of several studies that have shown the cytotoxic effects of amygdalin on the different cancer cell lines, however, the chemopreventive potential of amygdalin on the breast cancer cell line is not completely understood. We investigated the effect of amygdalin on the cell death and the level of pro-apoptotic Bax protein and anti-apoptotic Bcl-2 protein in SK-BR-3 human breast cancer cell line. The cell viability of SK-BR-3 cells was evaluated by MTT assay in different concentration of amygdalin. The level of Bax and Bcl-2 in SK-BR-3 cells were measured by western blot analysis. For statistical analysis, One-way ANOVA was used for the comparison of Bax and Bcl-2 protein level and percent of cell viability between groups. The molecular docking studies of amygdalin within the Bcl-2 (PDB ID: 4LVT) and HER2 (PDB ID: 3RCD) active site, were performed using AutoDock 4.2.5. Amygdalin induced a significant reduction of cell viability in SK-BR-3 after 24-h treatment in a dose-dependent manner. Also, amygdalin causes an increase in pro-apoptotic Bax protein and a decrease in anti-apoptotic Bcl-2 protein expression in the SK-BR-3 cells. Molecular docking studies showed that amygdalin interacts with the active site amino acids of Bcl-2 and HER2 through hydrogen bonding and some hydrophobic interactions. Amygdalin can induce apoptotic death in SK-BR-3 cells by increasing pro-apoptotic Bax protein and decreasing anti-apoptotic Bcl-2 protein expression. The results suggest that amygdalin may be a valuable candidate for the treatment of breast cancer, especially in HER2 positive cells.

Immunoregulatory and anti-inflammatory properties of Crocus sativus (Saffron) and its main active constituents: A review.

The medicinal uses of saffron, the dried stigmas of Crocus sativus L., have very long history in food coloring agent, and flavoring agent as well as traditional medicine for the treatment of several diseases. Crocus sativus is rich in carotenoids that affect immunity. This review summarizes the putative immunoregulatory effects of saffron and its active its derivatives including crocin, crocetin and safranal. In modern studies, its active constituents including protective effects, anti-inflammatory activities and molecular mechanisms of saffron on thimmune system have been demonstrated. Furthermore, the beneficial effects of saffron on inhibition of serum levels nuclear transcription factor κB (NF-κB) p65 unit, tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ) and some interleukin (IL) such as IL-1ß, IL-6, IL-12, IL-17A were reported. Furthermore, saffron has been known as the antagonist of NF-κB and the agonist of peroxisome proliferator-activated receptor gamma (PPAR-γ). In addition, saffron down-regulates the key pro-inflammatory enzymes such as myeloperoxidase (MPO), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), phospholipase A2, and prostanoids. This review summarizes the protective roles of C. sativus and its constituents against the pathogenesis of immune diseases and understanding a better management of these problems. Taken together, the main bioactive constituents of saffron may have health-promoting with important benefits in immune-related disorders. Finally, our study indicates that these bioactive constituents can affect both cellular and humoral immunity functions.

Mechanisms behind the atherothrombotic effects of acrolein, a review.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. The majority of cardiovascular complications are secondary to atherosclerosis. Extensive evidence has showed that environmental pollutants such as cigarette smoke and automobile exhaust increase the risk of developing atherosclerosis. Acrolein, a highly reactive unsaturated aldehyde, is found as a contaminant in air, food and water. Investigations during the last decades have shown that acrolein via various mechanisms such as oxidative stress, enhancement of inflammatory processes and the activation of matrix metalloproteases can initiate and accelerate atherosclerotic lesions formation. Furthermore, exposure to acrolein has been suggested to induce or exacerbate systemic dyslipidemia, an important risk factor for the development of atherosclerosis. Finally, there are reports which indicate acrolein can increase platelet activation and stimulation of the coagulation cascade which subsequently leads to thrombosis. Even a modest reduction of pollutants such as acrolein can have substantial effects on population health. Public health efforts to reduce acrolein exposures from known sources may lower the prevalence of vascular disease. This review focuses on the potential pathways and mechanisms behind the acrolein-induced atherothrombotic effects.

Immunological Responses against HER2-targeted Idarubicin-ZHER2 Conjugate in BALB/c Mice.

Targeting of cancerous cells with a high level of human epidermal growth factor receptor 2 (HER2) expressions by drug immunoconjugates is a new approach for specific delivery of chemotherapeutic agents. Our previous work indicated that idarubicin-ZHER2 affibody conjugate has a great potential for the treatment of HER2-overexpressing malignant cell lines but possible induced immune response against constructed conjugate was not addressed. In the current study, the possibility of induction of humoral and cellular immune responses against idarubicin-ZHER2 affibody conjugate in BALB/c mice was investigated. For assessment of the induced immune response, prepared and qualified idarubicin-ZHER2 affibody conjugate was administrated intravenously to BALB/c mice and the induced cellular immune response was evaluated by measuring secretion levels of interferon gamma (IFN-γ) and interleukin 10 (IL-10) cytokines by the splenocytes. Humoral response of treated mice was also assessed by measuring total immunoglobulin G (IgG) titer in mice sera. The obtained results showed that idarubicin-ZHER2 affibody conjugate at any examined concentrations could not induce secretion of IFN-γ as a pro-inflammatory cytokine. A mild increase in the level of regulatory IL-10 cytokine was seen in the treated mice although no dose dependency in the level of IL-10 production was observed. Furthermore, results showed that idarubicin-ZHER2 conjugate could not induce IgG production in the treated mice. Based on these findings, the idarubicin-ZHER2 conjugate can be considered as a candidate for the development of new therapeutics against HER2-overexpressing cancers although further in vivo studies are needed.

Specific Targeting of HER2-Positive Head and Neck Squamous Cell Carcinoma Line HN5 by Idarubicin-ZHER2 Affibody Conjugate.

BACKGROUND: Expression of human epidermal growth factor receptor type 2 (HER2) in head and neck squamous cell carcinoma (HNSCC) cell line HN5 can be employed with great opportunities of success for specific targeting of anti-cancer chemotherapeutic agents. OBJECTIVE: In the current study, HER2-specific affibody molecule, ZHER2:342 (an engineered protein with great affinity for HER2 receptors) was selected for conjugation to idarubicin (an anti-neoplastic antibiotic). METHOD: ZHER2:342 affibody gene with one added cysteine code at the its 5' end was synthesized de novo and then inserted into pET302 plasmid and transferred to E. Coli BL21 hosting system. After induction of protein expression, the recombinant ZHER2 affibody molecules were purified using Ni- NTA resin and purity was analyzed through SDS-PAGE. Affinity-purified affibody molecules were conjugated to idarubicin through a heterobifunctional crosslinker, sulfosuccinimidyl 4-(Nmaleimidomethyl) cyclohexane-1-carboxylate (Sulfo-SMCC). Specific toxicity of idarubicin-ZHER2 affibody conjugate against two HER2-positive cells, HN5 and MCF-7 was assessed through MTT assay after an exposure time of 48 hours with different concentrations of conjugate. RESULTS: Idarubicin in the non-conjugated form showed potent toxic effects against both cell lines, while HN5 cells were significantly more sensitive compared to MCF-7 cells. Dimeric ZHER2 affibody showed a mild decreasing effect on growth of both HN5 and MCF-7 cells at optimum concentration. Idarubicin-ZHER2 affibody conjugate at an optimum concentration reduced viability of HN5 cell line more efficiently compared to MCF-7 cell line. CONCLUSION: In conclusion, idarubicin-ZHER2 affibody conjugate in optimum concentrations can be used for specific targeting and killing of HN5 cells.

Computer-aided Drug Design and Drug Pharmacokinetic Prediction: A Mini-review.

Prediction of pharmacokinetics and drug targeting is a challenge in drug design. There are different types of software that can help to predict the pharmacokinetic profile of a drug. Quantitative structure-activity relationship (QSAR) modeling is used for drug design with less cost. Drug-excipient interactions are predicted by docking tools. Computerized drug target prediction and docking programs offer additional options to predict potential effects and adverse reactions of a given candidate as well as the best orientation of the compound on the receptor active site. Information on the absorption, distribution, metabolism and excretion of the drug in the body can enhance prediction of drug release and distribution in the blood and central nervous system (CNS). Computer- aided drug design and delivery can help to save the time and cost in the process of rational drug development.

Protective effects of chrysin on sub-acute diazinon-induced biochemical, hematological, histopathological alterations, and genotoxicity indices in male BALB/c mice.

Chrysin (CH) is a natural flavone which possesses antioxidant, anti-cancer, and anti-inflammatory properties. The aim of the present study was to investigate the effects of CH on biochemical parameters, histopathological changes, and genotoxicity and hematological indices in diazinon (DZN)-induced toxicity in BALB/c mice. We induced sub-acute toxicity in mice using DZN (20 mg/kg/day) and treated them with CH at the 12.5, 25, and 50 mg/kg/day five times/week in 28 days. In our study, DZN increased lipid profile and liver function tests (LFTs) and creatinine (Cr) but decreased the red blood cell acetylcholinesterase (RBC-AChE) activity and glucose level. Also, CH when co-treated with DZN changed the LFTs, lipid profile, creatine phosphokinase (CPK), lactate dehydrogenase (LDH) and bilirubin total (Bili-T). Moreover, a significant decrease in RBCs, hemoglobin (Hgb), hematocrit (HCT) level, and platelet counts were seen in DZN group but WBCs, lymphocytes, and neutrophils count increased. CH 25 and 50 mg/kg significantly improved alterations of WBCs, RBCs, Hgb, HCT, lymphocytes, neutrophils, and reticulocytes count when co-treated with DZN. Moreover, the co-administration of CH plus DZN recovered histopathological alterations in liver and kidney, as well as, improved the absolute and relative weight of kidney and liver. DZN induced the formation of bone marrow micronuclei (MN) but CH 50 mg/kg decreased the MN formation when co-treated with DZN. These results suggest that CH not only restores renal and hepatic markers, and histopathological alterations but also improves hematological and genotoxicity indices induced by DZN in mice.

An overview on immunoregulatory and anti-inflammatory properties of chrysin and flavonoids substances.

Inflammation and the pro-inflammatory cytokines are associated with numerous chronic diseases. Studies suggest that flavonoids, plant polyphenolic compound derivatives from natural origin, have a wide range of putative biological activities. Similar to other flavonoids, chrysin (CH) by its anti-oxidative and anti-inflammatory effects is a potential prophylactic agent in immunopathological and physicochemical injuries. This is an overview on putative immunomodulatory activities of flavonoids and beneficial health effects of these substances particularly, CH in the immune system. CH possesses potent immune-protective effects and suppresses inflammation in innate immune system which results to avoid damages induced by neutrophils and macrophages and suppresses immuno-inflammatory responses. Furthermore, beneficial effects of chrysin on inhibition of serum levels nuclear transcription factor κB (NF-κB) p65 unit, tumor necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß), IL-6, IL-12, IL-17A, interferon gamma (IFN-γ) was reported. Moreover, CH has been known as the antagonist of NF-kB and the agonist of peroxisome proliferator-activated receptor gamma (PPAR-γ) which in down regulation of the key pro-inflammatory enzymes such as myeloperoxidase (MPO), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), phospholipase A2, and prostanoids. Therefore, CH can improve immune system and neurodegenerative diseases. In recent years, there has been an increasing interest in compound derivatives from natural origin. Taken together, evidences show that flavonoids may have health-promoting and disease-preventing dietary compounds with important benefits in modern life styles.