A comprehensive review on nanocomposite biomaterials based on gelatin for bone tissue engineering

The creation of a suitable scaffold is a crucial step in the process of bone tissue engineering (BTE). The scaffold, acting as an artificial extracellular matrix, plays a significant role in determining the fate of cells by affecting their proliferation and differentiation in BTE. Therefore, careful consideration should be given to the fabrication approach and materials used for scaffold preparation. Natural polypeptides such as gelatin and collagen have been widely used for this purpose. The unique properties of nanoparticles, which vary depending on their size, charge, and physicochemical properties, have demonstrated potential in solving various challenges encountered in BTE. Therefore, nanocomposite biomaterials consisting of polymers and nanoparticles have been extensively used for BTE. Gelatin has also been utilized in combination with other nanomaterials to apply for this purpose. Composites of gelatin with various types of nanoparticles are particularly promising for creating scaffolds with superior biological and physicochemical properties. This review explores the use of nanocomposite biomaterials based on gelatin and various types of nanoparticles together for applications in bone tissue engineering.

Adipose Tissue-Mesenchymal Stem Cells Caused to Change the Methylation Status of hTERT Gene Promoter CpG Islands of Molt-4 Leukemia Cells as Cell-based Therapy

BACKGROUND

DNA methylation was considered as prognostic information in some hematological malignancies. Previous studies have reported the in vitro and in vivo biology role of mesenchymal stem cells (MSCs) on leukemic cells. The aim of this study was to investigate the effect of MSCs on the promoter methylation status of hTERT as a catalytic subunit of telomerase enzyme.

METHODS

In the experimental study, the Molt-4 leukemic cells were co-cultured with MSCs for 7 days. At the end of the co-culture period, the Molt-4 cells were collected, DNA and protein were extracted. Then methylation specific-PCR and western blotting were done for evaluating the hTERT gene promoter methylation status and cyclin D1 and hTERT protein expression, respectively. In the following, the flow cytometry was done for cell cycle distribution assay.

RESULTS

It was found that MSCs resulted in a significant decrease in the cyclin D1 and hTERT protein expression levels. Also, MSCs caused changes in the methylation status of the CpG islands in the hTERT gene promoter region. The following results showed that MSCs caused a significant increase in the number of cells at G0/G1 phase and arrest the G0/G1 phase as well as decrease in the cell proliferation of Molt-4 cells.

CONCLUSION

It is concluded that co-culture of MSCs with Molt-4 cells could be involved in changing the methylation status of hTERT gene promoter, cell cycle and hTERT protein expression; it could be potentially beneficial for further investigations regarding the cell transplantation and cell-based therapy.

L-Carnitine Reduced Cellular Aging of Bone Marrow Resident C-Kit+ Hematopoietic Progenitor Cells Through Telomere Dependent Pathways

BACKGROUND

Increased oxygen species levels can induce mitochondrial DNA damage and chromosomal aberrations and cause defective stem cell differentiation, leading finally to senescence of stem cells. In recent years, several studies have reported that antioxidants can improve stem cell survival and subsequently affect the potency and differentiation of these cells. Finding factors, which reduce the senescence tendency of stem cells upon expansion, has great potential for cellular therapy in regenerative medicine. This study aimed to evaluate the effects of L-carnitine (LC) on the aging of C-kit+ hematopoietic progenitor cells (HPCs) via examining the expression of some signaling pathway components.

METHODS

For this purpose, bone marrow resident C-kit+ HPCs were enriched by the magnetic-activated cell sorting (MACS) method and were characterized using flow cytometry as well as immunocytochemistry. Cells were treated with LC, and at the end of the treatment period, the cells were subjected to the realtime PCR technique along with a western blotting assay for measurement of the telomere length and assessment of protein expression, respectively.

RESULTS

The results showed that 0.2 mM LC caused the elongation of the telomere length and increased the TERT protein expression. In addition, a significant increase was observed in the protein expression of p38, p53, BCL2, and p16 as key components of the telomere-dependent pathway.

CONCLUSION

It can be concluded that LC can increase the telomere length as an effective factor in increasing the cell survival and maintenance of the C-kit+ HPCs via these signaling pathway components.

Recent advances in the production, reprogramming, and application of CAR-T cells for treating hematological malignancies

As genetically engineered cells, chimeric antigen receptor (CAR)-T cells express specific receptors on their surface to target and eliminate malignant cells. CAR proteins are equipped with elements that enhance the activity and survival of T cells. Once injected, CAR-T cells act as a "living drug" against tumor cells in the body. Up to now, CAR-T cell therapy has been demonstrated as a robust adoptive cell transfer (ACT) immunotherapeutic modality for eliminating tumor cells in refractory hematological malignancies. CAR-T cell therapy modality involves several steps, including the collecting of the blood from patients, the isolation of peripheral blood mononuclear cells (PBMCs), the enrichment of CD4⁺/CD8⁺ T cell, the genetic reprogramming, the expansion of modified T cells, and the injection of genetically engineered T cells. The production of CAR-T cells is a multi-step procedure, which needs precise and safety management systems, including good manufacturing practice (GMP), and in-line quality control and assurance. The current study describes the structure of CARs and concentrates on the next generations of CARs that are engaged in enhancing the anti-tumor responses and safety of the engineered T cells. This paper also highlights the important concerns in quality control and nonclinical research of CAR-T cells, as well as general insights into the manufacture, reprogramming, and application of CAR-T cells based on new and enhanced techniques for treating hematological malignancies. Besides, the application of the CRISPR-Cas9 genome editing technology and nanocarrier-based delivery systems containing CAR coding sequences to overcome the limitations of CAR-T cell therapy has also been explained.

The effects of L-carnitine-loaded solid lipid nanoparticles on performance, antioxidant parameters, and expression of genes associated with cholesterol metabolism in laying hens

The purpose of this study was to investigate the production performance, antioxidant parameters, egg yolk cholesterol content, and expression of genes related to cholesterol metabolism in laying hens fed L-carnitine (LC) and L-carnitine-loaded solid lipid nanoparticles (LC-SLNs). A total of 350 Hy-Line (w-36) laying hens at 50 wk of age (1520.0 ± 0.7 g) were randomly assigned to 35 units (5 replicates and 50 hens in each treatment) with seven dietary treatments as a completely randomized design. The dietary treatments were corn-soybean meal-based diets, including 1) Control (basal diet); 2) Basal diet +50 mg/kg LC (50LC); 3) Basal diet +100 mg/kg LC (100LC); 4) Basal diet +150 mg/kg LC (150LC); 5) Basal diet +50 mg/kg LC-SLNs (50LC-SLNs); 6) Basal diet +100 mg/kg LC-SLNs (100LC-SLNs) and 7) Basal diet +150 mg/kg LC-SLNs (150LC-SLNs). Results showed that the 50LC-SLNs had the least feed conversion ratio (FCR) in all groups (P < 0.05). The dietary supplementation of 100LC-SLNs decreased (P < 0.01) the egg yolk cholesterol concentration from 14.71 to 11.76 mg/g yolk (25%). The 50LC-SLNs group produced the most total antioxidant capacity with a difference of 58.44% compared to the control group (P < 0.01). The greatest amount of total superoxide dismutase was found for 50LC-SLNs (P < 0.05), while the glutathione peroxidase was not affected by the experimental treatments (P > 0.05). Serum malondialdehyde levels were reduced by 50.52% in laying hens fed 50LC-SLNs compared to the control group (P < 0.05). The transcript level of 3-hydroxy-3-methylglutaryl coenzyme A reductase was significantly decreased (P < 0.01) in the LC and LC-SLNs groups. The expression of cholesterol 7α-hydroxylase was significantly increased (P < 0.01) in the plain LC (∼83%) and LC-SLNs (∼91%) groups. The inclusion of LC-SLNs in the diet increased (P < 0.05) the villus height and decreased villus width in all three parts of the small intestine. Dietary inclusion of LC was found to reduce egg yolk and serum cholesterol content by improving the production performance and antioxidant status. The LC-SLNs groups were more affected than the plain LC groups, which may be attributed to the increased bioavailability of LC.

Hematopoietic stem cells characteristics: from isolation to transplantation

Abstract:

Hematopoietic stem cells (HSCs) have a self-renewal as well as pluripotency properties and are responsible to produce all types of blood cells. These cells are generated during embryonic development and transit through various anatomical niches (bone marrow microenvironment). Today, they are easily enriched from some sources including peripheral blood, bone marrow, and umbilical cord blood (UCB). HSCs have been used for many years to treat a variety of cancers and blood disorders such as various types of leukemia, lymphoma, myelodysplastic, myeloproliferative syndromes etc. Although almost 50 years have passed since the discovery of stem cells and many investigations have been done on cell therapy and regenerative medicine, further studies need to be conducted in this regard. This manuscript review the history, location, evolution, isolation, and therapeutic approaches of HSCs.

Mesenchymal stem cells promote caspase-3 expression of SH-SY5Y neuroblastoma cells via reducing telomerase activity and telomere length

Objective(s):

The use of mesenchymal stem cells in malignancies has attracted much attention due to their ability to deliver anticancer agents to tumors, including cytokines, chemokines, etc. This study aimed to investigate the effect of MSCs on the neuroblastoma SH-SY5Y cells through proliferation/apoptosis, senescence assessment, telomere length, and telomerase activity in vitro. BAX and BCL2 were also examined as potential signaling pathways in this process.

Materials and Methods:

For this reason, two cell populations (MSCs and SH-SY5Y cells) were co-cultured on trans-well plates for 7 days. In a subsequent step, SH-SY5Y cells were harvested from both control and experimental groups and subjected to flow cytometry, ELISA, real-time PCR, PCR-ELISA TRAP assay, and Western blotting assay for Ki67/Caspase3 investigation, β-Galactosidase assessment, telomere length, and telomerase activity assay. Also, expression of genes and proteins through real-time PCR and Western blotting demonstrated the involvement of the aforementioned signaling pathways in this process.

Results:

It was found that MSCs contributed significantly to decrease and increase of Ki-67 and Caspase-3, respectively. Also, MSCs dramatically reduced the length of telomere and telomerase activity and increased the β-Galactosidase activity in a significant manner. In addition, significant increase and decrease were also seen in BAX and BCL2 gene and protein expressions, respectively.

Conclusion:

These findings revealed that close interaction between MSCs and neuroblastoma cells causes inhibition of the SH-SY5Y cell proliferation and promotes cell senescence via BAX and caspase-3 cascade pathways.

Fabrication of a dual stimuli-responsive magnetic nanohydrogel for delivery of anticancer drugs

A dual stimuli-responsive magnetic nanohydrogel was fabricated as a potent drug delivery system (DDS) for 'smart' treatment of cancer by chemo/hyperthermia approach. For this objective, Fe₃O₄ nanoparticles (NPs) were produced via a co-precipitation approach and then modified by 3-(trimethoxysilyl) propylmethacrylate (MPS) moiety. The modified NPs were copolymerized with N,N'-(dimethylamino)ethyl methacrylate (DMAEMA), and maleic anhydride (MA) monomers by a free radical polymerization approach to afford a Fe₃O₄@P(DMAEMA-co-MA) core-shell NPs. Afterward, the NPs were shell crosslinked by the reaction of anhydride unites with neutralized cystamine (Cys). The fabricated pH- and reduction-responsive magnetic nanohydrogel was physically loaded with methotrexate (MTX), as an anticancer drug, and its drug loading efficiency (LE) was calculated as 64 ± 2.7%. The developed nanohydrogel/MTX exhibited proper stimuli-triggered drug release behavior that qualified it as an efficient DDS according to the abnormal micro-environment of cancerous tumors. The anticancer activity investigation using chemo/hyperthermia therapy approach by MTT-assay revealed that the nanohydrogel/MTX might show better clinical outcomes than those of the free MTX.

Acriflavine-loaded solid lipid nanoparticles: preparation, physicochemical characterization, and anti-proliferative properties

Acriflavine (ACF) is an antiseptic compound with the potential antitumor activity which is used for the fluorescent staining of RNA due to its dominant fluorescent emission at ∼515 nm. Here, solid lipid nanoparticles (SLNs) containing ACF (ACF-SLNs) were prepared and their physicochemical properties, potential geno/cytotoxicity, as well as the fluorescent properties were investigated. FITC-annexin V/PI staining and cell cycle assays were carried out to find the type of cellular death caused. Particle size analysis and SEM images revealed that spherical ACF-SLNs had a homogeneous dispersion with a mean diameter of 106 ± 5.7 nm. Drug loading (DL) of 31.25 ± 4.21 mg/mL and high encapsulation efficiency (EE%) (89.75 ± 5.44) were found. ACF-SLNs physically were relatively stable in terms of dispersion, size, and EE. The uptake study demonstrated the potential use of fluorescent ACF-SLNs in bio-distribution studies. MTT assay showed that plain ACF could induce growth inhibition of A549 cells with IC50 of 8.5, 6, and 4.5 μMol after 24, 48, and 72 hours, respectively, while ACF-SLNs had stable cytotoxic effects after 48 hours. ACF-SLNs induced remarkable apoptosis and even necrosis after 48 h. Conclusively, ACF-SLNs with acceptable physicochemical features showed increased bioimpacts after 48 h compared to plain ACF.

Sclareol Inhibits Hypoxia-Inducible Factor-1α Accumulation and Induces Apoptosis in Hypoxic Cancer Cells

Purpose: The hypoxia in solid tumors is associated with the resistance to chemo/radiotherapy. Hypoxia-inducible factor-1 (HIF-1) plays a key role in cell remodeling to hypoxia. Therefore, the inhibition of HIF-1 accumulation is considered a hopeful strategy for the treatment of cancer. Here, we aimed to evaluate the geno- and cytotoxicity properties of sclareol, a natural bicyclic diterpene alcohol, on A549 cells in CoCl₂-induced hypoxia.

Methods: The cytotoxicity and apoptosis-inducing properties of sclareol on the A549 cell were evaluated using MTT assay and Annexin V/PI staining, respectively in hypoxia. DAPI staining, DNA ladder, and comet assay were used to evaluate the genotoxicity. Further, the qPCR technique was employed to assess the expression of HIF-1α, HIF-1β, and downstream target genes (GluT1, and Eno1). Finally, the level of HIF-1α protein was evaluated through Western blotting in sclareol-treated cells in hypoxia.

Results: The inhibitory concentration (IC₅₀) of sclareol against A549 cells was 8 μg/mL at 48 hours in hypoxia. The genotoxicity of sclareol was confirmed in the cells treated with sclareol in hypoxia. Sclareol induced ~46% apoptosis and also necrosis in the hypoxic condition. The qPCR analyses showed an enhanced suppression of HIF-1α, HIF-1β, GluT1, and Eno1 due to the sclareol treatment in the hypoxia. Moreover, protein quantification analysis showed dose-dependently degradation of HIF-1α in hypoxia upon treatment with sclareol.

Conclusion: The results obtained here indicate that sclareol possesses dose-dependent cytotoxicity effects against A549 cells in hypoxia through inhibition of HIF-1α protein accumulation, increasing cell sensitivity to intracellular oxygen levels, and disruption of cell adaptation to hypoxia.

Natural polypeptides-based electrically conductive biomaterials for tissue engineering

Fabrication of an appropriate scaffold is the key fundamental step required for a successful tissue engineering (TE). The artificial scaffold as extracellular matrix in TE has noticeable role in the fate of cells in terms of their attachment, proliferation, differentiation, orientation and movement. In addition, chemical and electrical stimulations affect various behaviors of cells such as polarity and functionality. Therefore, the fabrication approach and materials used for the preparation of scaffold should be more considered. Various synthetic and natural polymers have been used extensively for the preparation of scaffolds. The electrically conductive polymers (ECPs), moreover, have been used in combination with other polymers to apply electric fields (EF) during TE. In this context, composites of natural polypeptides and ECPs can be taken into account as context for the preparation of suitable scaffolds with superior biological and physicochemical features. In this review, we overviewed the simultaneous usage of natural polypeptides and ECPs for the fabrication of scaffolds in TE.

Antisense LNA-loaded nanoparticles of star-shaped glucose-core PCL-PEG copolymer for enhanced inhibition of oncomiR-214 and nucleolin-mediated therapy of cisplatin-resistant ovarian cancer cells

We aimed to inhibit overexpressed oncomiR-214 in cisplatin (CIS)-resistant ovarian cancer (OC) and perform targeted therapy of sensitized cells using a novel polymeric drug delivery system (DDS). A system of nanoparticles (NPs) of star-shaped glucose-core polycaprolactone-polyethylene glycol (Glu-PCL-PEG) block copolymer containing cisplatin (CIS-PCL NPs) and locked nucleic acid (LNA) anti-miR-214 (LNA-PCL NPs) were prepared and anti-nucleolin aptamer was conjugated to the surface of prepared NPs to prepare Ap-CIS-PCL NPs and Ap-LNA-PCL NPs, respectively. The cancer-targeting ability of the NPs was confirmed and the CIS-resistant A2780 (A2780 R) cells were transfected with Ap-LNA-PCL NPs to inhibit oncomiR-214 and sensitize the cells to CIS. Next, the miR-214-inhibited cells were exposed to the Ap-CIS-NPs and the deracination efficiency of targeted DDS was evaluated. The oncomiR-214 in A2780 R cells were harnessed by Ap-LNA-PCL NPs, and nucleolin-mediated endocytosis of targeted polymeric DDSs containing CIS into miR-214-inhibited A2780 R cells caused enhanced apoptosis, which was further confirmed by apoptosis detection and evaluation of downstream genes expression. Targeted inhibition of miR-214 using the developed NPs containing LNA can decrease drug-resistant properties of cancer cells and may enhance the efficiency of targeted DDSs.

Aptamedicine: a new treatment modality in personalized cancer therapy

Aptamers ( Aps ) are short single-strand nucleic acids exhibiting unique 3D structure which facilitate their targeting potential against various cancer molecular markers ( CMMs ). Such features of Aps not only make them as suitable homing agents in targeted drug delivery systems (DDSs) but also candidate them as macromolecules that inhibit the interaction of the target ligand with other proteins. On the other hand, the conjugation of Aps with another therapeutic molecule such as antisense oligonucleotides (ASOs), siRNAs/miRNAs, Aps , toxins, chemotherapeutic agents, DNAzymes/Ribozymes provides hopeful strategy to eradicate the malignancies and overcome the off-target unwanted side effects. Such prominent features of Aps make them a promising treatment modality to overcome the tumor complexity and heterogeneity, which can be consequently applied for personalized therapy of cancer by using bispecific Ap-based therapeutics.

Triterpenoid corosolic acid attenuates HIF-1 stabilization upon cobalt (II) chloride-induced hypoxia in A549 human lung epithelial cancer cells

Hypoxia-inducible factor-1 is a target for the management of cancer. Here, the anti-proliferation properties of corosolic acid (CA) against A549 human lung epithelial cancer cells in CoCl₂-induced hypoxia is reported. CA was isolated from the roots of Salvia syriaca based on a bioassay-guided isolation platform and identified by 1D and 2D NMR experiments. Several cytotoxicies and genotoxicity analyses were performed using MTT, DAPI, cell cycle, DNA ladder, and annexin V/PI detection. Cobalt chloride (CoCl₂) was used to stimulate hypoxia. The adaptation of A549 cells to a stimulated hypoxic condition in the presence of CA was evaluated. CA decreased the growth of A549 cells with an IC₅₀ of 12 μg/mL at 48 h. Also, chromatin condensation and DNA fragmentation were detected as signs of apoptosis occurrence. CA induced ~85% apoptosis and even 1% necrosis. The expression of hypoxia-inducible factor-1 α (HIF-1α), HIF-1β and downstream genes was strongly suppressed in the presence of CA in CoCl₂-stimulated hypoxia condition. Results indicated that CA has remarkable cytotoxicity against the cancerous cell in hypoxia condition and may be regarded for preparation of new formulations for possible uses as supplement and medicine in cancer therapy.

AS1411 aptamer-decorated cisplatin-loaded poly(lactic-co-glycolic acid) nanoparticles for targeted therapy of miR-21-inhibited ovarian cancer cells

AIM

The overexpression of miRNA-21 correlates with the cisplatin (CIS) resistance in the ovarian cancers.

METHODS

AS1411 antinucleolin aptamer-decorated PEGylated poly(lactic-co-glycolic acid) nanoparticles containing CIS (Ap-CIS-NPs) and anti-miR-21 (Ap-anti-miR-21-NPs) were prepared, physicochemically investigated and their cancer-targeting ability was confirmed. CIS-resistant A2780 cells (A2780 R) were infected with anti-miR-21 using Ap-anti-miR-21-NPs to decrease the drug resistance and sensitize the cells to CIS. Afterward, miR-21-inhibited cells were exposed to the Ap-CIS-NPs.

RESULTS

Ap-anti-miR-21-NPs could infect the A2780 R cells mainly through nucleolin-mediated endocytosis and inhibit the endogenous miR-21. Targeted delivery of CIS using Ap-CIS-NPs into the miR-21-inhibited cells caused an enhanced mortality.

CONCLUSION

The targeted delivery of chemotherapeutics to the oncomiR-inhibited cells may find a robust application in cancer chemo/gene therapy.

Bispecific therapeutic aptamers for targeted therapy of cancer: a review on cellular perspective

Aptamers (Aps), as short single-strand nucleic acids, can bind to their corresponding molecular targets with the high affinity and specificity. In comparison with the monoclonal antibodies (mAbs) and peptides, unique physicochemical and biological characteristics of Aps make them excellent targeting agents for different types of cancer molecular markers (CMMs). Much attention has been paid to the Ap-based multifunctional chimeric and therapeutic systems, which provide promising outcomes in the targeted therapy of various formidable diseases, including malignancies. In the Ap-based chimeric systems, a targeting Ap is conjugated to another therapeutic molecule (e.g., siRNA/miRNA, Ap, toxins, chemotherapeutic agents, DNAzyme/ribozymes) with a capability of binding to a specific cell surface receptor at the desired target site. Having been engineered as multifunctional nanosystems (NSs), Ap-based hybrid scaffolds can be used to concurrently target multiple markers/pathways in cancerous cells, causing drastic inhibitory effects on the growth and the progression of tumor cells. Multi/bispecific Aps composed of two/more Aps provide a versatile tool for the optimal and active targeting of cell surface receptor(s) with markedly high affinity and avidity. Targeting the optimum activity of key receptors and dominant signaling pathways in the activation of immunity, the multi/bispecific Ap-based therapeutics can also be used to enhance the antitumor activity of the immune system. Further, the bispecific systems can be designed to induce cytotoxicity in a heterogeneous population of cancer cells with different CMMs. In this review, we provide some important insights into the construction and applications of the Ap-based chimeric NSs and discuss the multifunctional Ap chimera and their effects on the signaling pathways in cancer.

Recent advances in aptamer-armed multimodal theranostic nanosystems for imaging and targeted therapy of cancer

The side effects of chemotherapeutics during the course of cancer treatment limit their clinical outcomes. The most important mission of the modern cancer therapy modalities is the delivery of anticancer drugs specifically to the target cells/tissue in order to avoid/reduce any inadvertent non-specific impacts on the healthy normal cells. Nanocarriers decorated with a designated targeting ligand such as aptamers (Aps) and antibodies (Abs) are able to deliver cargo molecules to the target cells/tissue without affecting other neighboring cells, resulting in an improved treatment of cancer. For targeted therapy of cancer, different ligands (e.g., protein, peptide, Abs, Aps and small molecules) have widely been used in the development of different targeting drug delivery systems (DDSs). Of these homing agents, nucleic acid Aps show unique targeting potential with high binding affinity to a variety of biological targets (e.g., genes, peptides, proteins, and even cells and organs). Aps have widely been used as the targeting agent, in large part due to their unique 3D structure, simplicity in synthesis and functionalization, high chemical flexibility, low immunogenicity and toxicity, and cell/tissue penetration capability in some cases. Here, in this review, we provide important insights on Ap-decorated multimodal nanosystems (NSs) and discuss their applications in targeted therapy and imaging of cancer.

Survivin-deltaEx3: a novel biomarker for diagnosis of papillary thyroid carcinoma

CONTEXT

The most important problem in the case of thyroid nodules is the lack of suitable criteria for detecting malignant thyroid tumors from other nodules in the early stage. Variable expressions level of survivin, an inhibitory protein in apoptotic pathway, and its splice variants in malignant carcinoma versus well-differentiated normal tissues candidate them as reliable biomarkers in cancers.

AIM

To semi-quantitative detection of survivin and its splice variant, survivin-deltaEx3, in thyroid nodules.

SETTING AND DESIGN

We evaluated the expression level of mentioned biomarkers in thyroid nodules including carcinoma.

MATERIALS AND METHODS

Samples were collected from 61 thyroid nodules including malignant, adenoma, non-tumoral (goiter and thyroidities) as well as non-neoplastic normal tissues. Transcriptional levels were measured using semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and the results were normalized to β2microglubin (β2m) gene.

STATISTICAL ANALYSIS USED

Independent sample t-test was used to assess the significant variation of expression between different groups.

RESULT

Our data for a first time revealed that survivin-deltaEx3 is significantly up-regulated from normal to malignant thyroid carcinoma tissues (approximately ten fold).

CONCLUSION

High expression level of survivin and survivin-deltaEx3 in malignant papillary thyroid carcinoma suggested survivin gene expression and its splice variant, survivin-deltaEx3, can be potential new markers in diagnosis of human papillary thyroid carcinoma.

Comet assay: a method to evaluate genotoxicity of nano-drug delivery system

INTRODUCTION

Drug delivery systems could induce cellular toxicity as side effect of nanomaterials. The mechanism of toxicity usually involves DNA damage. The comet assay or single cell gel electrophoresis (SCGE) is a sensitive method for detecting strand damages in the DNA of a cell with applications in genotoxicity testing and molecular epidemiology as well as fundamental research in DNA damage and repair.

METHODS

In the current study, we reviewed recent drug delivery researches related to SCGE.

RESULTS

We found that one preference for choosing the assay is that comet images may result from apoptosis-mediated nuclear fragmentation. This method has been widely used over the last decade in several different areas. Overall cells, such as cultured cells are embedded in agarose on a microscope slide, lysed with detergent, and treated with high salt. Nucleoids are supercoiled DNA form. When the slide is faced to alkaline electrophoresis any breakages present in the DNA cause the supercoiling to relax locally and loops of DNA extend toward the anode as a ''comet tail''.

CONCLUSION

This article provides a relatively comprehensive review upon potentiality of the comet assay for assessment of DNA damage and accordingly it can be used as an informative platform in genotoxicity studies of drug delivery systems.

ASSESSMENT OF MC1R AND α-MSH GENE SEQUENCES IN IRANIAN VITILIGO PATIENTS

Background:

Vitiligo is an acquired pigmentary disorder of the skin that is caused by unknown factors and is characterized by white and depigmented patches that enlarge and become more numerous with time. Genetic factors, oxidative stress, autoimmunity, and neurochemical agents, such as catecholamines might also contribute to vitiligo. Cutaneous pigmentation is determined by the amounts of eumelanin and pheomelanin synthesized by the epidermal melanocytes and interference of melanocortin-1 receptor (MC1R), a G-protein coupled receptor, its normal agonist, alpha-melanocyte stimulating hormone (α-MSH), and key enzymes, such as tyrosinase, to protect against sun-induced DNA damage. The MC1R, a 7 pass trans-membrane G-protein coupled receptor, is a key control point in melanogenesis. Loss-of-function mutations at the MC1R are associated with a switch from eumelanin to pheomelanin production, resulting in a red or yellow coat color.

Aim:

In this research, we aim to examine the genetic variety of MC1R and α-MSH gene in 20 Iranian vitiligo patients and 20 healthy controls.

Materials and Methods:

Analysis of the MC1R coding gene was performed with direct sequencing.

Results:

We found the following 9 MC1R coding region variants: Arg163Gl (G488A), Arg227Leu (G680A), Val 97Phe (G289T), Asp184Asn (G550A), Arg227Lys (G680A), Arg142His (G425A), Val60Leu (G178T), Val247Met (C739A), and Val174Ile (G520A). We also found 2 frameshift changes: one of them was the Insertion of C (frameshift in Pro136, stop at Trp148) and the other, Insertion of G (frameshift in Pro256, stop at Trp 333). Of all the changes, the most common was Val60Leu at 5% in patients vs 20% in controls, Val247Met at 15% in patients vs 0% in controls and Val174Ile at 15% in controls and 0% in patients. The other variants showed a frequency <5% in both patients and controls. Also in this study, we have examined the frequency of single nucleotide polymorphisms within the α-MSH genes with direct sequencing in 20 patients and 20 healthy subjects but found no changes along this gene.

Conclusion:

We could not find any relationship between MC1R and α-MSH genes and their effect on the disease in Iranian vitiligo patients.