HER2-Specific Peptide (LTVSPWY) and Antibody (Herceptin) Targeted Core Cross-Linked Micelles for Breast Cancer: A Comparative Study.

This study aims to prepare a novel breast cancer-targeted micelle-based nanocarrier, which is stable in circulation, allowing intracellular drug release, and to investigate its cytotoxicity, apoptosis, and cytostatic effects, in vitro. The shell part of the micelle is composed of zwitterionic sulfobetaine ((N-3-sulfopropyl-N,N-dimethylamonium)ethyl methacrylate), while the core part is formed by another block, consisting of AEMA (2-aminoethyl methacrylamide), DEGMA (di(ethylene glycol) methyl ether methacrylate), and a vinyl-functionalized, acid-sensitive cross-linker. Following this, a targeting agent (peptide (LTVSPWY) and antibody (Herceptin®)), in varying amounts, were coupled to the micelles, and they were characterized by 1H NMR, FTIR (Fourier-transform infrared spectroscopy), Zetasizer, BCA protein assay, and fluorescence spectrophotometer. The cytotoxic, cytostatic, apoptotic, and genotoxic effects of doxorubicin-loaded micelles were investigated on SKBR-3 (human epidermal growth factor receptor 2 (HER2)-positive) and MCF10-A (HER2-negative). According to the results, peptide-carrying micelles showed a higher targeting efficiency and better cytostatic, apoptotic, and genotoxic activities than antibody-carrying and non-targeted micelles. Also, micelles masked the toxicity of naked DOX on healthy cells. In conclusion, this nanocarrier system has great potential to be used in different drug-targeting strategies, by changing targeting agents and drugs.

Therapeutic Potential of Luteolin on Cancer.

Cancer is a global concern, as the rate of incidence is increasing each year. The challenges related to the current chemotherapy drugs, such as the concerns related to toxicity, turn to cancer therapeutic research to discover alternative therapy strategies that are less toxic to normal cells. Among those studies, the use of flavonoids-natural compounds produced by plants as secondary metabolites for cancer therapy-has been a hot topic in cancer treatment. Luteolin, a flavonoid that has been present in many fruits, vegetables, and herbs, has been identified to exhibit numerous biological activities, including anti-inflammatory, antidiabetic, and anticancer properties. The anticancer property of Luteolin has been extensively researched in many cancer types and has been related to its ability to inhibit tumor growth by targeting cellular processes such as apoptosis, angiogenesis, migration, and cell cycle progression. It achieves this by interacting with various signaling pathways and proteins. In the current review, the molecular targets of Luteolin as it exerts its anticancer properties, the combination therapy that includes Luteolin with other flavonoids or chemotherapeutic drugs, and the nanodelivery strategies for Luteolin are described for several cancer types.

scMAGS: Marker gene selection from scRNA-seq data for spatial transcriptomics studies.

Single-Cell RNA sequencing (scRNA-seq) has provided unprecedented opportunities for exploring gene expression and thus uncovering regulatory relationships between genes at the single-cell level. However, scRNA-seq relies on isolating cells from tissues. Therefore, the spatial context of the regulatory processes is lost. A recent technological innovation, spatial transcriptomics, allows for the measurement of gene expression while preserving spatial information. An initial step in the spatial transcriptomic analysis is to identify the cell type, which requires a careful selection of cell-specific marker genes. For this purpose, currently, scRNA-seq data is used to select a limited number of marker genes from among all genes that distinguish cell types from each other. This study proposes scMAGS (single-cell MArker Gene Selection), a novel method for marker gene selection from scRNA-seq data for spatial transcriptomics studies. scMAGS uses a filtering step in which the candidate genes are identified before the marker gene selection step. For the selection of marker genes, cluster validity indices, the Silhouette index, or the Calinski-Harabasz index (for large datasets) are utilized. Experimental results showed that, in comparison to the existing methods, scMAGS is scalable, fast, and accurate. Even for large datasets with millions of cells, scMAGS could find the required number of marker genes in a reasonable amount of time with fewer memory requirements. scMAGS is made freely available at https://github.com/doganlab/scmags and can be downloaded from the Python Package Directory (PyPI) software repository with the command pip install scmags.

Biodiversity: the overlooked source of human health.

Biodiversity is the measure of the variation of lifeforms in a given ecological system. Biodiversity provides ecosystems with the robustness, stability, and resilience that sustains them. This is ultimately essential for our survival because we depend on the services that natural ecosystems provide (food, fresh water, air, climate, and medicine). Despite this, human activity is driving an unprecedented rate of biodiversity decline, which may jeopardize the life-support systems of the planet if no urgent action is taken. In this article we show why biodiversity is essential for human health. We raise our case and focus on the biomedicine services that are enabled by biodiversity, and we present known and novel approaches to promote biodiversity conservation.

MicroRNAs and Long Non-coding RNAs as Novel Targets in Anti-cancer Drug Development.

Non-coding RNAs comprise the majority of RNAs that have been transcribed from the human genome, and these non-coding RNAs have essential regulatory roles in the cellular processes. They have been discovered to influence the expression of the genes, including tumorsuppressive and oncogenes, that establish the non-coding RNAs as novel targets for anti-cancer drug development. Among non-coding RNAs, microRNAs have been extensively studied in terms of cancer biology, and some microRNA-based therapeutics have been reached in clinical studies. Even though most of the research regarding targeting non-coding RNAs for anti-cancer drug development focused on microRNAs, long non-coding RNAs have also started to gain importance as potential therapeutic targets for cancer therapy. In this chapter, the strategies and importance of targeting microRNAs and long non-coding RNAs will be described, along with the clinical studies that involve microRNA-based cancer therapeutics and preclinical studies that involve long noncoding RNA-based therapeutics. Finally, the delivery strategies that have great importance in the effective delivery of the non-coding RNA-based cancer therapeutics, hence the therapy's effectiveness, will be described.

Investigating the potential therapeutic role of targeting STAT3 for overcoming drug resistance by regulating energy metabolism in chronic myeloid leukemia cells.

Objectives: STATs are one of the initial targets of emerging anti-cancer agents due to their regulatory roles in survival, apoptosis, drug response, and cellular metabolism in CML. Aberrant STAT3 activity promotes malignancy, and acts as a metabolic switcher in cancer cell metabolism, contributing to resistance to TKI nilotinib. To investigate the possible therapeutic effects of targeting STAT3 to overcome nilotinib resistance by evaluating various cellular responses in both sensitive and nilotinib resistant CML cells and to test the hypothesis that energy metabolism modulation could be a mechanism for re-sensitization to nilotinib in resistant cells. Materials and Methods: By using RNAi-mediated STAT3 gene silencing, cell viability and proliferation assays, apoptotic analysis, expressional regulations of STAT mRNA transcripts, STAT3 total, pTyr705, pSer727 protein expression levels, and metabolic activity as energy metabolism was determined in CML model K562 cells, in vitro. Results: Targeting STAT3 sensitized both parental and especially nilotinib resistant cells by decreasing leukemic cell survival; inducing leukemic cell apoptosis, and decreasing STAT3 mRNA and protein expression levels. Besides, cell energy phenotype was modulated by switching energy metabolism from aerobic glycolysis to mitochondrial respiration in resistant cells. RNAi-mediated STAT3 silencing accelerated the sensitization of leukemia cells to nilotinib treatment, and STAT3-dependent energy metabolism regulation could be another underlying mechanism for regaining nilotinib response. Conclusion: Targeting STAT3 is an efficient strategy for improving the development of novel CML therapeutics for regaining nilotinib response, and re-sensitization of resistant cells could be mediated by induced apoptosis and regulation in energy metabolism.

The Role of MiRNA in Cancer: Pathogenesis, Diagnosis, and Treatment.

Cancer is also determined by the alterations of oncogenes and tumor suppressor genes. These gene expressions can be regulated by microRNAs (miRNA). At this point, researchers focus on addressing two main questions: "How are oncogenes and/or tumor suppressor genes regulated by miRNAs?" and "Which other mechanisms in cancer cells are regulated by miRNAs?" In this work we focus on gathering the publications answering these questions. The expression of miRNAs is affected by amplification, deletion or mutation. These processes are controlled by oncogenes and tumor suppressor genes, which regulate different mechanisms of cancer initiation and progression including cell proliferation, cell growth, apoptosis, DNA repair, invasion, angiogenesis, metastasis, drug resistance, metabolic regulation, and immune response regulation in cancer cells. In addition, profiling of miRNA is an important step in developing a new therapeutic approach for cancer.

HER2-Targeted, Degradable Core Cross-Linked Micelles for Specific and Dual pH-Sensitive DOX Release.

Here, a targeted, dual-pH responsive, and stable micelle nanocarrier is designed, which specifically selects an HER2 receptor on breast cancer cells. Intracellularly degradable and stabilized micelles are prepared by core cross-linking via reversible addition-fragmentation chain-transfer (RAFT) polymerization with an acid-sensitive cross-linker followed by the conjugation of maleimide-doxorubicin to the pyridyl disulfide-modified micelles. Multifunctional nanocarriers are obtained by coupling HER2-specific peptide. Formation of micelles, addition of peptide and doxorubicin (DOX) are confirmed structurally by spectroscopical techniques. Size and morphological characterization are performed by Zetasizer and transmission electron microscope (TEM). For the physicochemical verification of the synergistic acid-triggered degradation induced by acetal and hydrazone bond degradation, Infrared spectroscopy and particle size measurements are used. Drug release studies show that DOX release is accelerated at acidic pH. DOX-conjugated HER2-specific peptide-carrying nanocarriers significantly enhance cytotoxicity toward SKBR-3 cells. More importantly, no selectivity toward MCF-10A cells is observed compared to HER2(+) SKBR-3 cells. Formulations cause apoptosis depending on Bax and Caspase-3 and cell cycle arrest in G2 phase. This study shows a novel system for HER2-targeted therapy of breast cancer with a multifunctional nanocarrier, which has higher stability, dual pH-sensitivity, selectivity, and it can be an efficient way of targeted anticancer drug delivery.

Synergistic Apoptotic Effects of Bortezomib and Methylstat on Multiple Myeloma Cells.

BACKGROUND: In this study, we aimed to determine synergistic apoptotic and cytotoxic effects of methylstat and bortezomib on U266 and ARH77 multiple myeloma (MM) cells. METHODS: Cytotoxic effects of the drugs were demonstrated by MTT cell proliferation assay while apoptotic effects were examined by loss of mitochondrial membrane potential (MMP) by JC-1 MMP detection kit, changes in caspase-3 enzyme activity and Annexin-V apoptosis assay by flow cytometry. Expression levels of apoptotic and antiapoptotic genes were examined by qRT-PCR. RESULTS: Our results showed that combination of methylstat and bortezomib have synergistic antiproliferative effect on MM cells as compared to either agent alone. These results were also confirmed by showing synergistic apoptotic effects determined by increased loss of mitochondrial membrane potential and increased caspase-3 enzyme activity and relocation of phosphotidyleserine on the cell membrane by Annexin-V/PI double staining. Combination of bortezomib with methylstat arrested cells at the S phase of the cell cycle. Methylstat treatment caused upregulation of FASLG, NGFR, TNF, TNFRS10B and TNFRS1B apoptotic genes and downregulation of AKT1, AVEN, BAG1 BCL2L2 and RELA antiapoptotic genes in a dose and time dependent manner. CONCLUSION: In conclusion, our data suggested that bortezomib in combination with methylstat decreased cell proliferation and induced apoptosis significantly in U266 and ARH77 cells. When supported with in vivo analyses, methylstat might be considered as a potential new agent for the treatment of MM.

Therapeutic Potentials of Inhibition of Jumonji C Domain-containing Demethylases in Acute Myeloid Leukemia

Objective: Acute myeloid leukemia (AML) is a complex disease affected by both genetic and epigenetic factors. Histone methylation and demethylation are types of epigenetic modification in chromatin remodeling and gene expression. Abnormal expression of histone demethylases is indicated in many types of cancer including AML. Although many commercial drugs are available to treat AML, an absolute cure has not been discovered yet. However, inhibition of demethylases could be a potential cure for AML. Methylstat is a chemical agent that inhibits the Jumonji C domain-containing demethylases. Materials and Methods: The cytotoxic and apoptotic effects of methylstat and doxorubicin on HL-60 cells were detected by MTT cell viability assay, double staining of treated cells with annexin-V/propidium iodide, and caspase-3 activity assay. Mitochondrial activity was analyzed using JC-1 dye. The expression levels of the BCL2 and BCL2L1 anti-apoptotic genes in HL-60 cells were determined using real-time polymerase chain reaction (PCR). Lastly, the cytostatic effect was determined by cell cycle analysis. Results: In our research, cytotoxic, cytostatic, and apoptotic effects of methylstat on human HL-60 cells were investigated. Cytotoxic and cytostatic analyses revealed that methylstat decreased cell proliferation in a dose-dependent cytotoxic manner and arrested HL-60 cells in the G2/M and S phases. Methylstat also induced apoptosis through the loss of mitochondrial membrane potential and increases in caspase-3 enzyme activity. The expression levels of BCL2 and BCL2L1 were also decreased according to real-time PCR results. Finally, the combination of methylstat with doxorubicin resulted in synergistic cytotoxic effects on HL-60 cells. Conclusion: Taken together, these results demonstrate that methylstat may be a powerful candidate as a drug component of AML treatment protocols.

An answer to colon cancer treatment by mesenchymal stem cell originated from adipose tissue.

OBJECTIVES: Colon cancer is risen up with its complex mechanism that directly impacts on its treatment as well as its common prevalence. Mesenchymal stem cells (MSCs) have been considered as a therapeutic candidate for conventional disease including cancer. In this research, we have focused on apoptotic effects of adipose tissue-derived MSCs in colon cancer. MATERIALS AND METHODS: MSCs were obtained from adipose tissue and characterized by Flowcytometer using suitable antibodies. MSCs, HT-29, HCT-116, RKO and healthy cell line MRC5 were cultured by different seeding procedure. After cell viability assay, changes in caspase 3 enzyme activity and the level of phosphatidylserine were measured. RESULTS: For cell viability assay, a 48 hr incubation period was chosen to seed all cells together. There was a 1.36-fold decrease in caspase 3 enzyme activity by co-treatment of RKO and MSCs in addition to 2.02-fold decrease in HT-29 and MSCs co-treatment, and 1.103-fold increase in HCT-116 and MSCs. The results demonstrated that HCT-116 led to the highest rate of apoptotic cell death (7.5%) compared with other cells. CONCLUSION: We suggest that MSCs might remain a new treatment option for cancer by its differentiation and repair capacity.

A minimally invasive transfer method of mesenchymal stem cells to the intact periodontal ligament of rat teeth: a preliminary study.

The aim of this study was to introduce a minimally invasive procedure for mesenchymal stem cell (MSC) transfer into the intact periodontal ligament (PDL) of the molar teeth in rats. Ten 12-week-old Wistar albino rats were used for this preliminary study. MSCs were obtained from bones of two animals and were labeled with green fluorescent protein (GFP). Four animals were randomly selected for MSC injection, while 4 animals served as a control group. Samples were prepared for histological analysis, Cox-2 mRNA expression polymerase chain reaction analysis, and fluorescent microscopy evaluation. The number of total cells, number of osteoclastic cells, and Cox-2 mRNA expression levels of the periodontal tissue of teeth were calculated. The number of total cells was increased with MSC injections in PDL significantly (P < 0.001). The number of osteoclastic cells and Cox-2 mRNA expression were found to be similar for the two groups. GFP-labeled MSCs were observed with an expected luminescence on the smear samples of the PDL with transferred MSCs. The results of this preliminary study demonstrate successful evidence of transferring MSCs to intact PDL in a nonsurgical way and offer a minimally invasive procedure for transfer of MSCs to periodontal tissues.

Effect of Molecular Architecture on Cell Interactions and Stealth Properties of PEG.

PEGylation, covalent attachment of PEG to therapeutic biomolecules, in which suboptimal pharmacokinetic profiles limiting their therapeutic utility are of concern, is a widely applied technology. However, this technology has been challenged by reduced bioactivity of biomolecules upon PEGylation and immunogenicity of PEG triggering immune response and abrogating clinical efficacy, which collectively necessitate development of stealth polymer alternatives. Here we demonstrate that comb-shape poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA), a stealth polymer alternative, has a more compact structure than PEG and self-organize into nanoparticles in a molecular weight dependent manner. Most notably, we show that comb-shape POEGMA promotes significantly higher cellular uptake and exhibits less steric hindrance imposed on the conjugated biomolecule than PEG. Collectively, comb-shape POEGMA offers a versatile alternative to PEG for stealth polymer-biomolecule conjugation applications.

Effects of Intraperitoneal Injection of Allogeneic Bone Marrow-derived Mesenchymal Stem Cells on Bronchiolitis Obliterans in Mice Model.

Bone marrow-derived mesenchymal stem cells (BMSCs) can ameliorate a variety of lung diseases such as asthma, lung fibrosis, and acute lung injury by its anti-inflammatory and immunmodulatory effects. In this study, we developed a mouse model of bronchiolitis obliterans (BO) and evaluated the effects of the intraperitoneal administration of BMSCs on lung histopathology and cytokine levels. 25 BALB/c mice were divided into four groups; control group (Group I), BO developed and 1x106 BMSCs-injected group (Group II), non-BO, 1x106 BMSCs-injected group (Group III), and BO developed and saline-injected group (Group IV). Histological and immunohistochemical findings of the lung tissue and the migration of BMSCs to the lung were evaluated using light and confocal microscopy techniques. Confocal microscopy evaluations showed that there was no noteworthy amount of BMSCs in the lung tissue of group III while significant amount of BMSCs was detected in group II. Wall thicknesses of terminal bronchiole and periterminal bronchiolar collagen deposition were significantly lower in group II compared to the group IV (p<0.05). Furthermore, according to the immunohistochemical staining results, CD3, CD4, CD8, CD20, CD68 and neutrophil elastase positive immune cells of group II were stained more positive than group IV cells (p<0.05). IFN-γ IL-2 and TNF-α levels in bronchoalveolar lavage fluid (BALF) were significantly lower in group II compared to group IV (p<0.05). The findings of this study indicate that intraperitoneally administered BMSCs have potent effects on histopatological changes of the lung tissue and cytokine levels in the murine model of BO.

Flow cytometry: basic principles and applications.

Flow cytometry is a sophisticated instrument measuring multiple physical characteristics of a single cell such as size and granularity simultaneously as the cell flows in suspension through a measuring device. Its working depends on the light scattering features of the cells under investigation, which may be derived from dyes or monoclonal antibodies targeting either extracellular molecules located on the surface or intracellular molecules inside the cell. This approach makes flow cytometry a powerful tool for detailed analysis of complex populations in a short period of time. This review covers the general principles and selected applications of flow cytometry such as immunophenotyping of peripheral blood cells, analysis of apoptosis and detection of cytokines. Additionally, this report provides a basic understanding of flow cytometry technology essential for all users as well as the methods used to analyze and interpret the data. Moreover, recent progresses in flow cytometry have been discussed in order to give an opinion about the future importance of this technology.

Intraperitoneal mesenchymal stem cell administration ameliorates allergic rhinitis in the murine model.

Previous studies showed that bone marrow-derived mesenchymal stem cells (BMSCs) could ameliorate a variety of immune-mediated and inflammatory diseases due to their immunomodulatory and anti-inflammatory effects. In this study, we developed a mouse model of ovalbumin (OVA) induced allergic inflammation in the upper airways and evaluated the effects of the intraperitoneal administration of BMSCs on allergic inflammation. Twenty-five BALB/c mice were divided into five groups; group I (control group), group II (sensitized and challenged with OVA and treated with saline-placebo group), group III (sensitized and challenged with OVA and treated with 1 × 106 BMSCs), group IV (sensitized and challenged with OVA and treated with 2 × 106 BMSCs), and group V (sensitized and challenged with phosphate buffered saline (PBS) and treated with 1 × 106 BMSCs). Histopathological features (number of goblet cells, eosinophils and mast cells, basement membrane, epithelium thickness, and subepithelial smooth muscle thickness) of the upper and lower airways and BMSCs migration to nasal and lung tissue were evaluated using light and confocal microscopes. Levels of cytokines in the nasal lavage fluid and lung tissue supernatants were measured using enzyme-linked immunosorbent assay (ELISA). Confocal microscopic analysis showed that there was no significant amount of BMSCs in the nasal and lung tissues of group V. However, significant amount of BMSCs were observed in group III and IV. In OVA-induced AR groups (group II, III, and IV), histopathological findings of chronic asthma, such as elevated subepithelial smooth muscle thickness, epithelium thickness, and number of goblet and mast cells, were determined. Furthermore, the number of nasal goblet and eosinophil cells, histopathological findings of chronic asthma, and IL-4, IL-5, IL-13, and NO levels was significantly lower in both BMSCs-treated groups compared to the placebo group. Our findings indicated that histopathological findings of chronic asthma were also observed in mice upon AR induction. BMSCs migrated to the nasal and lung tissues following intraperitoneal delivery and ameliorated to the airway remodeling and airway inflammation both in the upper and lower airways via the inhibition of T helper (Th) 2 immune response in the murine model of AR.

Effects of cell-mediated osteoprotegerin gene transfer and mesenchymal stem cell applications on orthodontically induced root resorption of rat teeth.

Aim: The aim of this study is to evaluate and compare therapeutic effects of mesenchymal stem cell (MSCs) and osteoprotegerin (OPG) gene transfer applications on inhibition and/or repair of orthodontically induced inflammatory root resorption (OIIRR). Materials and methods: Thirty Wistar rats were divided into four groups as untreated group (negative control), treated with orthodontic appliance group (positive control), MSCs injection group, and OPG transfected MSCs [gene therapy (GT) group]. About 100g of orthodontic force was applied to upper first molar teeth of rats for 14 days. MSCs and transfected MSC injections were performed at 1st, 6th, and 11th days to the MSC and GT group rats. At the end of experiment, upper first molar teeth were prepared for genetical, scanning electron microscopy (SEM), fluorescent microscopy, and haematoxylin eosin-tartrate resistant acid phosphatase staining histological analyses. Number of total cells, number of osteoclastic cells, number of resorption lacunae, resorption area ratio, SEM resorption ratio, OPG, RANKL, Cox-2 gene expression levels at the periodontal ligament (PDL) were calculated. Paired t-test, Kruskal-Wallis, and chi-square tests were performed. Results: Transferred MSCs showed marked fluorescence in PDL. The results revealed that number of osteoclastic cells, resorption lacunae, resorption area ratio, RANKL, and Cox-2 were reduced after single MSC injections significantly (P < 0.05). GT group showed the lowest number of osteoclastic cells (P < 0.01), number of resorption lacunae, resorption area ratio, and highest OPG expression (P < 0.001). Conclusions: Taken together all these results, MSCs and GT showed marked inhibition and/or repair effects on OIIRR during orthodontic treatment on rats.

Cell Proliferation and Cytotoxicity Assays.

Cell viability is defined as the number of healthy cells in a sample and proliferation of cells is a vital indicator for understanding the mechanisms in action of certain genes, proteins and pathways involved cell survival or death after exposing to toxic agents. Generally, methods used to determine viability are also common for the detection of cell proliferation. Cell cytotoxicity and proliferation assays are generally used for drug screening to detect whether the test molecules have effects on cell proliferation or display direct cytotoxic effects. Regardless of the type of cell-based assay being used, it is important to know how many viable cells are remaining at the end of the experiment. There are a variety of assay methods based on various cell functions such as enzyme activity, cell membrane permeability, cell adherence, ATP production, co-enzyme production, and nucleotide uptake activity. These methods could be basically classified into different categories: (I) dye exclusion methods such as trypan blue dye exclusion assay, (II) methods based on metabolic activity, (III) ATP assay, (IV) sulforhodamine B assay, (V) protease viability marker assay, (VI) clonogenic cell survival assay, (VII) DNA synthesis cell proliferation assays and (V) raman micro-spectroscopy. In order to choose the optimal viability assay, the cell type, applied culture conditions, and the specific questions being asked should be considered in detail. This particular review aims to provide an overview of common cell proliferation and cytotoxicity assays together with their own advantages and disadvantages, their methodologies, comparisons and intended purposes.