ON/OFF based synergetic plasmonic photothermal drug release approach through core-satellite like mussel-inspired polydopamine nanoparticles

One of the studies on new drug delivery and release systems that has increased in recent years is the study using plasmonic nanoparticles. In this study, polydopamine nanoparticles (PDOP NPs), which contribute to photothermal drug release by near infrared radiation (NIR), were decorated with gold nanoparticles (AuNPs) to utilize their plasmonic properties, and a core-satellite-like system was formed. With this approach, epirubicin (EPI)-loaded PDOP NPs were prepared by utilizing the plasmonic properties of AuNPs. Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD) methods were used to evaluate the structural properties of these particles. The release behavior of the prepared structures in acidic (pH 5.0) and neutral (pH 7.4) environments based on the ON/OFF approach was also examined. The biocompatibility properties of the particles were evaluated on mouse fibroblast (L929) and anticancer activities on neuroblastoma (SH-SY5Y) cells. The effects of prepared EPI-loaded particles and laser-controlled drug release on ROS production, genotoxicity, and apoptosis were also investigated in SH-SY5Y cells. With the calculated combination index (CI) value, it was shown that the activity of EPI-loaded AuNP@PDOP NPs increased synergistically with the ON/OFF-based approach. The developed combination approach is considered to be remarkable and promising for further evaluation before clinical use.

Development of Gemcitabine Loaded PLGA/Lecithin Nanoparticles for Non-Small Cell Lung Cancer Therapy

BACKGROUND

Compared to polymeric nanoparticles prepared using non-lipid surfactants, lecithin addition forms larger nanoparticles and exhibits higher drug loading and the stability of nanoparticles can be conferred by adding Vitamin E Polyethylene Glycol Succinate (TPGS) into the formulation.

AIM

The aim of this study is to prepare Gemcitabine (Gem) loaded lecithin/PLGA nanoparticles. Moreover, the effect of TPGS and sodium cholate (SK) on the preparation of lecithin/PLGA nanoparticles was compared.

METHODS

It was found that while PC addition into PLGATPGS nanoparticles formed larger particles (251.3± 6.0 nm for Gem-PLGATPGS NPs and 516,9 ± 3.9 nm for Gem-PLGA-PCTPGS NPs), the particle size of PLGASK nanoparticles was not affected by lecithin addition (p>0.05;).

RESULTS

In cytotoxicity studies, it was found that the SK-MES-1 cell inhibition rates of Gem-PLGATPGS NPs, Gem-PLGA-PCTPGS NPs, Gem-PLGASK NPs, Gem-PLGA-PCSK NPs were similar with free Gem (p>0.05;). In cytotoxicity studies, it was found that the encapsulation into nanoparticles did not change the cytotoxicity of the drug. However, higher cellular uptake has been observed when the lecithin was used in the preparation of PLGA nanoparticles.

CONCLUSION

Compared with free Gem, the Gem-loaded nanoparticles enhanced the uptake of the drug by SK-MES-1 cells which can increase the effect of gemcitabine for non-small cell lung cancer therapy.

History repeats itself: Horse originated Hyperimmune sera production against SARS CoV-2

BACKGROUND/AIM

SARS-CoV-2 disease was announced as a pandemic by The World Health Organization on early 2020. It is still threatening the world population. Here, we aimed to produce hyperimmune sera that contain immunoglobulin G and F(ab')2 fragments sourced from horse antibodies as an urgent response to the pandemic.

MATERIALS AND METHODS

SARS-CoV-2 was produced and inactivated with three different methods [formaldehyde (FA), formaldehyde and binary ethylene amine (FA+BEI), and heat treatment]. After in vitro inactivation control, immunogens were mixed with Freund?s adjuvant, thereafter horses (n: 2 for FA, 4 for FA + BEI, 2 for Heat inactivation) and New Zealand rabbits (n: 6 for FA, 6 for FA + BEI, 6 for Heat inactivation) were immunized four times. Neutralizing antibody levels of the sera were measured at the 4th, 6th and 8th weeks. When the antibodies were detected at the peak level, plasma was collected from horses and hyperimmune sera procured after the purification process.

RESULTS

Horses and rabbits produced highly neutralizing antibodies against the SARS-CoV-2 in FA and FA + BEI inactivation groups, foreign proteins were removed effectively after purification.

CONCLUSION

This study presents a profitable practice to develop horse specific antisera against SARS-CoV-2 for emergency and low-cost response. In further studies, new purification methods can be used to increase the efficiency of the final product.

Evaluation of cytotoxic and genotoxic effects of paclitaxel-loaded PLGA nanoparticles in neuroblastoma cells

Neuroblastoma, a neoplasm of the sympathetic nervous system, is the second most common extracranial malignant tumor of childhood and the most common solid tumor of infancy. Paclitaxel (taxol), a diterpenoid pseudoalkaloid isolated from the shells of Taxus brevifolia, is the first taxane derivative used in the clinic for cancer treatment. Poly (lactic-co-glycolic acid) (PLGA) is one of the most successfully used biodegradable polymers for drug delivery which has a minimum systemic toxicity. This study aimed to evaluate the cytotoxicity and genotoxicity of paclitaxel nanoencapsulated with PLGA. Cytotoxic effects were determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method and genotoxic effects were determined by single cell gel electrophoresis (Comet) method in human neuroblastoma cells (SH-SY5Y). According to our results, the viability of cells treated with concentrations higher than 10 nM of free paclitaxel and paclitaxel loaded PLGA nanoparticles for 48 and 72 h was found lower than 50%. Additionally, DNA damage increased with the increase of nanoparticle dose when the cells exposed to paclitaxel loaded PLGA nanoparticles for 24, 48 and 72 h. It can be concluded that PLGA nanoparticles can be considered as a biocompatible carrier system for drug delivery and might be promising agent against neuroblastoma.

In vitro evaluation of two different types of obidoxime-loaded nanoparticles for cytotoxicity and blood-brain barrier transport

Nerve agents (NA) are chemical warfare munitions and their exposure causes a progressive inhibition of acetylcholinesterase (AChE). This inhibition causes NA-induced brain damage in central nervous system (CNS). Oximes reactivate AChE in both the peripheral nervous system and the CNS. Transport of the oxime across the blood-brain barrier (BBB) in the existed therapeutic concentrations at the brain parenchyma determines the effectiveness of antidote therapy on respiratory depression and NA-induced brain damage. However, oximes could not cross the BBB in therapeutic concentrations. The aim of this study was to load AChE reactivator obidoxime chloride to PLGA and PEG-b-PLGA nanoparticles and to improve the BBB transport of the molecule. Brain microvascular endothelial cells were used as the BBB model. 79.3 ± 4.2% of obidoxime was released from PLGA nanoparticles and 88.2 ± 4.4% of obidoxime was released from PEG-b-PLGA nanoparticles within 24 h. It was found that PEG-b-PLGA nanoparticles were ideal drug carrier because of its low tissue toxicity, few side effects, and controllable drug release profile. Transport efficiency of obidoxime across the BBB is a major challenge in the prevention of the CNS, the effectiveness of NA poisoning and new strategies like using obidoxime-loaded PEG-b-PLGA nanoparticles could overcome this challenge for the management of NA-induced brain damage.

Effect simultaneous delivery with P-glycoprotein inhibitor and nanoparticle administration of doxorubicin on cellular uptake and in vitro anticancer activity

Multidrug resistance (MDR) is the most common problem of inadequate therapeutic response in tumor cells. Many trials has been developed to overcome drug efflux by P-glycoprotein (P-gp). For instance, co-administration of a number of drugs called chemosensitizers or MDR modulators with a chemotherapeutic agent to inhibit drug efflux. But for optimal synergy, the drug and inhibitor combination may need to be temporally colocalized in the tumor cells. In this study, we encapsulated the Ver and Dox in PLGA nanoparticles to inhibit the P-gp drug efflux in breast cancer. Moreover, the effect of either Dox solution (Dox_S), Dox nanoparticles (Dox_NP), Dox_S + Ver_S, Dox_NP + Ver_S, Dox_NP + Ver_NP or Dox-Ver_NP was evaluated. It was found that co administration of Dox_NP with Ver_NP (70.76%) showed similar cellular uptake of Dox to Dox/Ver combination solution (70.62%). However it is observed that Dox_NP + Ver_NP has the highest apoptotic activity (early apoptotic 13.52 ± 0.06%, late apoptotic 53.94 ± 0.15%) on human breast adenocarcinoma (MCF 7) cells. Hence, it is suggested that Dox_NP + Ver_NP is a promising administration for tumor therapy.

Microarray analysis of the gene expression profile in triethylene glycol dimethacrylate-treated human dental pulp cells

OBJECTIVE

Triethylene glycol dimethacrylate (TEGDMA) is an important resin monomer commonly used in the structure of dental restorative materials. Recent studies have shown that unpolymerized resin monomers may be released into the oral environment and cause harmful biological effects. We investigated changes in the gene expression profiles of TEGDMA-treated human dental pulp cells (hDPCs) following short- (1-day) and long-term (7-days) exposure.

MATERIALS AND METHODS

HDPCs were exposed to a noncytotoxic concentration of TEGDMA, and gene expression profiles were evaluated by microarray analysis. The results were confirmed by quantitative reverse-transcriptase PCR (qRT PCR).

RESULTS

In total, 1282 and 1319 genes (up- or down-regulated) were differentially expressed compared with control group after the 1- and 7-day incubation periods, respectively. Biological ontology-based analyses revealed that metabolic, cellular, and developmental processes constituted the largest groups of biological functional processes. qRT-PCR analysis on bone morphogenetic protein-2 (BMP-2), BMP-4, secreted protein, acidic, cysteine-rich, collagen type I alpha 1, oxidative stress-induced growth inhibitor 1, MMP3, interleukin-6, and heme oxygenase-1 genes confirmed the changes in expression observed in the microarray analysis.

CONCLUSIONS

Our results suggest that TEGDMA can change the many functions of hDPCs through large changes in gene expression levels and complex interactions with different signaling pathways.

Gene expression changes in bioceramic paste-treated human dental pulp cells

We evaluated the gene expression profiles of human dental pulp cells exposed to iRoot BP using microarray after 24 and 72 h. The results were verified using quantitative reverse transcriptase PCR analysis. Of the 36,000 transcripts arrayed, 21 were up-regulated and 15 were down-regulated by more than two fold. The largest group of up-regulated genes included those involved in nucleobase-containing compound metabolic processes, cell communication, protein metabolic processes, developmental processes, and biological regulation. The largest groups of down-regulated genes were those involved in cell communication, development, and biological regulation processes. In conclusion, iRoot BP affects the expression of genes involved in different biological processes in human dental pulp cells. (J Oral Sci 58, 307-315, 2016).

Hypoxia inhibits mineralization ability of human dental pulp cells treated with TEGDMA but increases cell survival in accordance with the culture time

OBJECTIVE

To evaluate the cytotoxicity and mineralization effects of TEGDMA in human dental pulp cells (hDPCs) under hypoxic and normoxic culture conditions.

DESIGN

Cell viability was evaluated using XTT assay after incubation periods of 24, 48, or 72h. The expression of mineralization-related genes (osteonectin, osteopontin, dentin sialophosphoprotein, collagen type 1) and heme oxygenase 1 (HO-1) was assessed by quantitative real-time polymerase chain reaction at 24 and 72h.

RESULTS

In XTT assay, viability was higher in 0.3, 1, 2, 4, and 5mM groups in the presence of 21% O₂ after 24h (p<0.05). Additionally, while 0.3, 1, 2mM groups had higher cell viability in the presence of 21% O₂ after 48h (p<0.05), in 3mM groups cell viability was higher under 3% O₂ than 21% O₂ after both 24 and 48h (p<0.05). 1-3mM groups had higher cell viability under 3% O₂ after 72h (p<0.05). There was no difference between 4 and 5mM groups with regards to cell viability after 48 or 72h (p>0.05). In the gene expression study, TEGDMA-treated hDPCs showed lower mineralization potential in the presence of 3% than with 21% O₂ (p<0.05). hDPCs revealed higher HO 1 expression in 0.3 and 1mM groups under hypoxic than under normoxic conditions after a 72-h time period (p<0.001).

CONCLUSIONS

Hypoxic conditions increased cell survival in accordance with the culture period but inhibited the odontoblastic differentiation of hDPCs treated with TEGDMA.

Improvement of a liposomal formulation with a native molecule: calcitriol

Calcitriol and doxorubicin co-loaded liposomes created improved cytotoxicity on Namalwa cells compared to doxorubicin loaded liposomes or free drug treatments.

In vitro anti-oxidant, cytotoxic and pro-apoptotic effects of Achillea teretifolia Willd extracts on human prostate cancer cell lines

BACKGROUND

The majority of Achillea species are the most important native economic plants of Anatolia. They include highly bioactive compounds, so they have therapeutic applications.

OBJECTIVE

In the present study, the aim was to investigate in vitro anti-oxidant, cytotoxic and pro-apoptotic effects of Achillea teretifolia Willd extracts (Turkish name: Beyaz civanperÇemi).

MATERIALS AND METHODS

The anti-oxidant potential of the extracts was analyzed by the free radical 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and total phenolic content methods. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to detect cytotoxicity of the extracts onhuman prostate cancer cell lines (DU145 and PC-3) and human gingival fibroblast (HGF) cells. mRNA expression levels of pro-apoptotic (bax, caspase-3) and anti-apoptotic (bcl-2) genes were measured by quantitative real-time polymerase chain reaction.

RESULTS

The results showed that extracts exhibited a remarkable DPPH scavenging activity, and total phenolic content of the methanol extract was higher than that of the water extract. As time and concentration were increased, the methanol extract exhibited a more powerful cytotoxic effect on prostate cancer cells. In prostate cancer cells, the levels of mRNA expression of the bax and caspase-3 genes were significantly up-regulated (P < 0.05), whereas the expression of bcl-2 was down-regulated (P < 0.05). In HGF cells, there were no cytotoxic effect and apoptosis induction triggered by the extracts.

CONCLUSION

The methanol extract had more powerful anti-oxidant, cytotoxic and pro-apoptotic effects than the water extract. The extracts could be good anti-oxidant sources, and they might include anti-cancer compounds triggering the cytotoxicity and the apoptosis on prostate cancer cells.

Antimicrobial activity against periodontopathogenic bacteria, antioxidant and cytotoxic effects of various extracts from endemic Thermopsis turcica

OBJECTIVE

To investigate the in vitro antimicrobial potential of Thermopsis turcica Kit Tan, Vural & Küçüködük against periodontopathogenic bacteria, its antioxidant activity and cytotoxic effect on various cancer cell lines.

METHODS

In vitro antimicrobial activities of ethanol, methanol, ethyl acetate (EtAc), n-hexane and water extracts of Thermopsis turcica herb against periodontopathogenic bacteria, Aggregatibacter actinomycetemcomitans ATCC 29523 and Porphyromonas gingivalis ATCC 33277 were tested by agar well diffusion, minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Antioxidant properties of the extracts were evaluated by 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity and β-carotene bleaching methods. Amounts of phenolic contents of the extracts were also analysed by using the Folin-Ciocalteu reagent. Additionally, cytotoxic activity of the extracts on androgen-insensitive prostate cancer, androgen-sensitive prostate cancer, chronic myelogenous leukemia and acute promyelocytic leukemia human cancer cell lines were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Human gingival fibroblast cells were used as a control.

RESULTS

Our data showed that EtAc extract had the highest antimicrobial effect on Aggregatibacter actinomycetemcomitans (MIC: 1.562 mg/mL, MBC: 3.124 mg/mL) and Porphyromonas gingivalis (MIC: 0.781 mg/mL, MBC: 1.562 mg/mL). In antioxidant assays, EtAc extract exhibited also the highest radical scavenging activity [IC50=(30.0±0.3) µg/mL] and the highest inhibition [(74.35±0.30)%] against lineloic acide oxidation. The amount of phenolic content of it was also the highest [(162.5±1.2) µg/mg gallic acid]. In cytotoxic assay, only ethanol [IC50=(80.00±1.21) µg/mL] and EtAc extract [IC50=(70.0±0.9) µg/mL] were toxic on acute promyelocytic leukemia cells at 20-100 µg/mL (P<0.05). However, no toxic effect was observed on human gingival fibroblast cells.

CONCLUSIONS

According to our findings, owing to its antioxidant and cytotoxic potential, EtAc extract might include anticancer agents for acute promyelocytic leukemia.

The -137G/C Polymorphism in Interleukin-18 Gene Promoter Contributes to Chronic Lymphocytic and Chronic Myelogenous Leukemia Risk in Turkish Patients

Objective:

Interleukin-18 (IL-18) is a cytokine that belongs to the IL-1 superfamily and is secreted by various immune and nonimmune cells. Evidence has shown that IL-18 has both anticancer and procancer effects. The aim of this study was to evaluate the relationship between IL-18 gene polymorphisms and susceptibility to chronic lymphocytic leukemias (CLL) and chronic myelogenous leukemias (CML) in Turkish patients.

Materials and Methods:

The frequencies of polymorphisms (rs61667799(G/T), rs5744227(C/G), rs5744228(A/G), and rs187238(G/C)) were studied in 20 CLL patients, 30 CML patients, and 30 healthy individuals. The genotyping was performed by polymerase chain reaction and DNA sequencing analysis.

Results:

Significant associations were detected between the IL-18 rs187238(G/C) polymorphism and chronic leukemia. A higher prevalence of the C allele was found in CML cases with respect to controls. The GC heterozygous and CC homozygous genotypes were associated with risk of CML when compared with controls. However, prevalence of the C allele was not significantly high in CLL cases with respect to controls. There was only a significant difference between the homozygous CC genotype of CLL patients and the control group; thus, it can be concluded that the CC genotype may be associated with the risk of CLL. Based on our data, there were no significant associations between the IL-18 rs61667799(G/T), rs5744227(C/G), or rs5744228(A/G) polymorphisms and CLL or CML.

Conclusions:

IL-18 gene promoter rs187238(G/C) polymorphism is associated with chronic leukemia in the Turkish population. However, due to the limited number of studied patients, these are preliminary results that show the association between -137G/C polymorphism and patients (CLL and CML). Further large-scale studies combined with haplotype and expression analysis are required to validate the current findings.

Abstract P4-19-05: Breast cancer campaign tissue bank human cell culture programme: Generating new biomaterials for breast research

Background:

In-vitro model systems provide an important tool in breast cancer research and, over recent years, there have been considerable advances in their construction. However, despite these advances, the majority of models still employ a narrow range of established cell lines, which frequently are not appropriate for the in-vivo cell type they are representing1.

Method:

As part of the Breast Cancer Campaign Tissue Bank, we have developed a cell culture programme which feeds into the main tissue collection and involves the systematic generation of materials from normal, high-risk, cancer-containing and malignant breast tissue in order to make available a breadth of material to the research community.

Following informed patient consent, fresh tissue is retrieved and, using tissue digestion and magnetic bead technology2, purified cell populations are isolated, characterized and frozen down, or further processed for DNA and RNA isolation.

Results:

We have isolated purified populations of luminal epithelial, myoepithelial and fibroblast cells from normal breast, risk-reduction (BRCA1 and BRCA2 mutated) breast and from morphologically normal breast tissue surrounding breast cancer. We have generated matched surround and tumour-associated fibroblasts, as well as matched tumour epithelial and tumour-associated fibroblast cell isolates.

These cells have been incorporated into 2- and 3-D culture models and we have demonstrated successful genetic manipulation, with siRNA gene knockdown and gene over-expression through retroviral transduction. Immortalisation of selected cell populations is currently underway.

Intact organoids and tissue explants have also been generated for in-vitro experimentation. Matched frozen and FFPE samples are available, together with full clinicopathological data. The research community can access these biomaterials via a web-based search portal, with full user support.

Conclusion:

Through this cell culture programme we aim to make available a wider and more appropriate range of materials for breast research, which should allow more clinically relevant model systems to be developed and add value to breast cancer biobanking.

References:

1. Thompson A., et al. Evaluation of the current knowledge limitations in breast cancer research: a gap analysis. Breast Cancer Research 2008; 10: R26.

2. Gomm J.J. et al. Isolation of pure populations of epithelial and myoepithelial cells from the normal human mammary gland using immunomagnetic separation with Dynabeads. Analytical Biochemistry 1995; 226: 91-99.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-19-05.

Optimization of transfection of green fluorescent protein in pursuing mesenchymal stem cells in vivo

OBJECTIVE

Green Fluorescent Protein (GFP) has been used as a marker of gene expression and a single cell marker in living organisms in cell biology studies. The important areas that GFP is used are expression levels of different genes in different organisms by inserting GFP in these genes and as a marker in living cells. In this study, we tried to optimize transfection of mesenchymal stem cells, (MSCs) used for regeneration of damaged tissues in animals, by GFP containing plasmid vector by which MSCs can be followed in vivo.

METHODS

To this aim, phM-GFP plasmid vector carrying GFP gene and effectene transfection reagent were used.

RESULTS

The data revealed that twice transfection of MSCs resulted in higher expression of GFP for longer times as compared to once transfected MSCs. On the other hand, leaving the chemical transfection agents in the medium induced apoptosis after a while.

CONCLUSION

As a conclusion we suggest the transfection of MSCs twice with 48 hours interval and removal of transfection agents after 8 hours which removed toxic and apoptotic effects of the chemicals.

Red grape seed extract and its compound resveratrol exert cytotoxic effect to various human cancer lines

Modern medicinal agents currently available for treatment of cancers are very expensive, toxic, and less effective in treating some of the disease. Thus, one must investigate further in detail the agents derived from natural sources, such as grape seed, for the prevention and treatment of cancer and disease. In recent years interest of researchers has focused on grape seed and nowadays scientists have used extracts of grape seed to treat different health problems including cancer. We examined the cytotoxic effect of red grape seed extract (GSE) and its main compound resveratrol (RES) on different human cancer cell lines representing various solid tumors and hematological malignancies at the same time. Red GSE was prepared by using 1, 1, 1, 2- Tetrafluoroethane extraction method. Cytotoxicity of the extract and RES was evaluated by using trypan blue dye exclusion method and MTT assay. The results of our study show that GSE and RES have cytotoxic activities in varying degree in several cancer cell lines. There has not been any study evaluating the GES and RES in the same cell lines and in the same conditions. But, it is still needed to have more pre-clinical and laboratory studies to validate the usefulness of these agents either alone or in combination with existing therapy.