Metabolic Rate and Oxidative Stress as a Risk Factors in the Development of Colorectal Cancer.

There is growing evidence that the body's energy expenditures constitute a significant risk factor for the development of most deadly diseases, including cancer. Our aim was to investigate the impact of basal metabolic rate (BMR) on the growth and progression of colorectal cancer (CRC). To do so, we used a unique model consisting of three lines of laboratory mice (Mus musculus) artificially selected for high (HBMR) and low (LBMR) basal metabolic rate and randomly bred individuals (non-selected, NSBMR). The experimental individuals were implanted with human colorectal cancer cells DLD-1. The variation in BMR between the lines allowed for testing the impact of whole-body metabolism on oxidative and antioxidant parameters in the liver throughout the cancerogenesis process. We investigated the dependence between metabolic values, reactive oxygen species (ROS) levels, and Kelch-like ECH-associated protein 1-based E3 ligase complexes (Keap1) gene activity in these animals. We found that the HBMR strain had a higher concentration of oxidative enzymes compared to the LBMR and NSBMR. Furthermore, the growth rate of CRC tumors was associated with alterations in the levels of oxidative stress enzymes and Keap1 expression in animals with a high metabolic rate. Our results indicate that a faster growth and development of CRC line DLD-1 is associated with enzymatic redox imbalance in animals with a high BMR.

Tumor-Homing Peptides as Crucial Component of Magnetic-Based Delivery Systems: Recent Developments and Pharmacoeconomical Perspective.

According to data from the World Health Organization (WHO), cancer is considered to be one of the leading causes of death worldwide, and new therapeutic approaches, especially improved novel cancer treatment regimens, are in high demand. Considering that many chemotherapeutic drugs tend to have poor pharmacokinetic profiles, including rapid clearance and limited on-site accumulation, a combined approach with tumor-homing peptide (THP)-functionalized magnetic nanoparticles could lead to remarkable improvements. This is confirmed by an increasing number of papers in this field, showing that the on-target peptide functionalization of magnetic nanoparticles improves their penetration properties and ensures tumor-specific binding, which results in an increased clinical response. This review aims to highlight the potential applications of THPs in combination with magnetic carriers across various fields, including a pharmacoeconomic perspective.

Membrane-Active Thermoresponsive Block Copolymers Containing a Diacylglycerol-Based Segment: RAFT Synthesis, Doxorubicin Encapsulation, and Evaluation of Cytotoxicity against Breast Cancer Cells.

Herein, we report the formation of drug delivery systems from original thermoresponsive block copolymers containing lipid-based segments. Two acrylate monomers derived from palmitic- or oleic-acid-based diacylglycerols (DAGs) were synthesized and polymerized by the reversible addition-fragmentation chain transfer (RAFT) method. Well-defined DAG-based polymers with targeted molar masses and narrow molar mass distributions were next used as macro-chain transfer agents (macro-CTAs) for the polymerization of N-isopropylacrylamide (NIPAAm) or N-vinylcaprolactam (NVCL). The obtained amphiphilic block copolymers were formed into polymeric nanoparticles (PNPs) with and without encapsulated doxorubicin and characterized. Their biological assessment indicated appropriate cytocompatibility with the representatives of normal cells. Furthermore, compared to the free drug, increased cytotoxicity and apoptosis or necrosis induction in breast cancer cells was documented, including a highly aggressive and invasive triple-negative MDA-MB-231 cell line.

Tamoxifen Modulates the Immune Landscape of the Tumour Microenvironment: The Paired Siglec-5/14 Checkpoint in Anti-Tumour Immunity in an In Vitro Model of Breast Cancer.

Since the role of sialome-Siglec axis has been described as a regulatory checkpoint of immune homeostasis, the promotion of stimulatory or inhibitory Siglec-related mechanisms is crucial in cancer progression and therapy. Here, we investigated the effect of tamoxifen on the sialic acid-Siglec interplay and its significance in immune conversion in breast cancer. To mimic the tumour microenvironment, we used oestrogen-dependent or oestrogen-independent breast cancer cells/THP-1 monocytes transwell co-cultures exposed to tamoxifen and/or ß-estradiol. We found changes in the cytokine profiles accompanied by immune phenotype switching, as measured by the expression of arginase-1. The immunomodulatory effects of tamoxifen in THP-1 cells occurred with the altered SIGLEC5 and SIGLEC14 genes and the expression of their products, as confirmed by RT-PCR and flow cytometry. Additionally, exposure to tamoxifen increased the binding of Siglec-5 and Siglec-14 fusion proteins to breast cancer cells; however, these effects appeared to be unassociated with oestrogen dependency. Our results suggest that tamoxifen-induced alterations in the immune activity of breast cancer reflect a crosstalk between the Siglec-expressing cells and the tumour's sialome. Given the distribution of Siglec-5/14, the expression profile of inhibitory and activatory Siglecs in breast cancer patients may be useful in the verification of therapeutic strategies and predicting the tumour's behaviour and the patient's overall survival.

Statins-From Fungi to Pharmacy.

Statins have been used in the treatment of hyperlipidemia, both as monotherapy and in combination therapy. Natural fermentation processes of fungi such as Monascus spp., Penicillium spp., Aspergillus terreus, and Pleurotus ostreatus have given rise to natural statins. Compactin (mevastatin), the original naturally occurring statin, is the primary biotransformation substrate in the manufacturing process of marketed drugs. Statins are classified into natural, semi-synthetic derivatives of natural statins, and synthetic ones. Synthetic statins differ from natural statins in their structural composition, with the only common feature being the HMG-CoA-like moiety responsible for suppressing HMG-CoA reductase. Statins do not differ significantly regarding their pleiotropic and adverse effects, but their characteristics depend on their pharmacokinetic parameters and chemical properties. This paper focuses on describing the processes of obtaining natural statins, detailing the pharmacokinetics of available statins, divided into natural and synthetic, and indicating their pleiotropic effects.

Folic-Acid-Conjugated Thermoresponsive Polymeric Particles for Targeted Delivery of 5-Fluorouracil to CRC Cells.

Colorectal cancer is the fourth most common cancer worldwide and the third most frequently diagnosed form of cancer associated with high mortality rates. Recently, targeted drug delivery systems have been under increasing attention owing to advantages such as high therapeutic effectiveness with a significant depletion in adverse events. In this report, we describe the biocompatible and thermoresponsive FA-conjugated PHEA-b-PNIPAAm copolymers as nanocarriers for the delivery of 5-FU. The block copolymers were obtained using RAFT (Reversible Addition-Fragmentation chain Transfer) polymerization and were characterized by methods such as SEC (Size Exclusion Chromatography), NMR (Nuclear Magnetic Resonance), UV-Vis (Ultraviolet-Visible), FT-IR (Fourier Transform Infrared) spectroscopy, and TGA (Thermogravimetric Analysis). Nanoparticles were formed from polymers with and without the drug-5-fluorouracil, which was confirmed using DLS (Dynamic Light Scattering), zeta potential measurements, and TEM (Transmission Electron Microscopy) imaging. The cloud points of the polymers were found to be close to the temperature of the human body. Eventually, polymeric carriers were tested as drug delivery systems for the safety, compatibility, and targeting of colorectal cancer cells (CRC). The biological evaluation indicated high compatibility with the representative host cells. Furthermore, it showed that proposed nanosystems might have therapeutic potential as mitigators for 5-FU-induced monocytopenia, cardiotoxicity, and other chemotherapy-associated disorders. Moreover, results show increased cytotoxicity against cancer cells compared to the drug, including a line with a drug resistance phenotype. Additionally, the ability of synthesized carriers to induce apoptosis and necrosis in treated CRC cells has been confirmed. Undoubtedly, the presented aspects of colorectal cancer therapy promise future solutions to overcome the conventional limitations of current treatment regimens for this type of cancer and to improve the quality of life of the patients.

Beneficial Proapoptotic Effect of Heterobasidion Annosum Extract in Colorectal Cancer Xenograft Mouse Model.

Fungal extracts possess potential anticancer activity against many malignant neoplastic diseases. In this research, we focused on the evaluation of Heterobasidion annosum (HA) extract in colorectal cancer in an in vivo model. The mice with implanted DLD-1 human cancer cells were given HA extract, the referential drug-5-fluorouracil (5FU), or were treated with its combination. Thereafter, tumor volume was measured and apoptotic proteins such as caspase-8, caspase-3, p53, Bcl-2, and survivin were analyzed in mice serum with an ELISA assay. The Ki-67 protein was assessed in tumor cells by immunohistochemical examination. The biggest volumes of tumors were confirmed in the DLD-1 group, while the lowest were observed in the population treated with 5FU and/or HA extract. The assessment of apoptosis showed increased concentrations of caspase 8 and p53 protein after the combined administration of 5FU and HA extract. The levels of survivin and Bcl-2 were decreased in all tested groups compared to the DLD-1 group. Moreover, we observed a positive reaction for Ki-67 protein in all tested groups. Our findings confirm the apoptotic effect of extract given alone or with 5FU. The obtained results are innovative and provide a basis for further research concerning the antitumor activity of the HA extract, especially in the range of its interaction with an anticancer chemotherapeutic agent.

A head-to-head comparison review of biological and toxicological studies of isomaltulose, d-tagatose, and trehalose on glycemic control.

Diabetes mellitus is the most common metabolic disorder contributing to significant morbidity and mortality in humans. Different preventive and therapeutic agents, as well as various pharmacological strategies or non-pharmacological tools, improve the glycemic profile of diabetic patients. Isomaltulose, d-tagatose, and trehalose are naturally occurring, low glycemic sugars that are not synthesized by humans but widely used in food industries. Various studies have shown that these carbohydrates can regulate glucose metabolism and provide support in maintaining glucose homeostasis in patients with diabetes, but also can improve insulin response, subsequently leading to better control of hyperglycemia. In this review, we discussed the anti-hyperglycemic effects of isomaltulose, D-tagatose, and trehalose, comparing their properties with other known sweeteners, and highlighting their importance for the development of the pharmaceutical and food industries.

Establishment of In Vitro and In Vivo Anticolorectal Cancer Efficacy of Lithocholic Acid-Based Imidazolium Salts.

Imidazolium salts (IMSs) are the subject of many studies showing their anticancer activities. In this research, a series of novel imidazolium salts substituted with lithocholic acid (LCA) and alkyl chains of various lengths (S1-S10) were evaluated against colon cancer cells. A significant reduction in the viability and metabolic activity was obtained in vitro for DLD-1 and HT-29 cell lines when treated with tested salts. The results showed that the activities of tested agents are directly related to the alkyl chain length, where S6-S8 compounds were the most cytotoxic against the DLD-1 line and S4-S10 against HT-29. The research performed on the xenograft model of mice demonstrated a lower tendency of tumor growth in the group receiving compound S6, compared with the group receiving 5-fluorouracil (5-FU). Obtained results indicate the activity of S6 in the induction of apoptosis and necrosis in induced colorectal cancer. LCA-based imidazolium salts may be candidates for chemotherapeutic agents against colorectal cancer.

Dehydroepiandrosterone derived imidazolium salts and their antimicrobial efficacy.

Hybrid molecules consisting of steroid-imidazolium salts reveal interesting biological properties, especially regarding antimicrobial activities. Novel dehydroepiandrosterone derived imidazolium salts (11 salts) with side chains of different lengths were obtained in an efficient and straightforward synthetic route. Antimicrobial properties of new salts were examined by determining their minimum inhibitory concentrations (MICs). They were studied against several strains of bacteria, including clinical isolates of MRSA, and fungi. New compounds showed high activity against Gram-positive bacteria and Candida albicans as well as good compatibility with the representatives of the host cells when applied at concentrations corresponding to MIC value. The studies indicated high antimicrobial efficacy of imidazolium salts against the above-mentioned microorganisms with low hemolytic activity at a concentration that restricts the growth of the microorganisms. The interference of salts with the immune defense system, the influence on the biological activity of monocytes/macrophages measured by their viability and metabolic activity was also studied. The new compounds have shown immunoprotective properties.

Sialic Acid-Modified Nanoparticles-New Approaches in the Glioma Management-Perspective Review.

The cell surface is covered by a dense and complex network of glycans attached to the membrane proteins and lipids. In gliomas, the aberrant sialylation, as the final stage of glycosylation, is an important regulatory mechanism of malignant cell behavior and correlates with worse prognosis. Better understanding of the role of sialylation in cellular and molecular processes opens a new way in the development of therapeutic tools for human brain tumors. According to the recent clinical observation, the cellular heterogeneity, activity of brain cancer stem cells (BCSCs), immune evasion, and function of the blood-brain barrier (BBB) are attractive targets for new therapeutic strategies. In this review, we summarize the importance of sialic acid-modified nanoparticles in brain tumor progression.

The Paired Siglecs in Brain Tumours Therapy: The Immunomodulatory Effect of Dexamethasone and Temozolomide in Human Glioma In Vitro Model.

The paired sialic acid-binding immunoglobulin like lectins (Siglecs) are characterized by similar cellular distribution and ligand recognition but opposing signalling functions attributed to different intracellular sequences. Since sialic acid-Siglec axis are known to control immune homeostasis, the imbalance between activatory and inhibitory mechanisms of glycan-dependent immune control is considered to promote pathology. The role of sialylation in cancer is described, however, its importance in immune regulation in gliomas is not fully understood. The experimental and clinical observation suggest that dexamethasone (Dex) and temozolomide (TMZ), used in the glioma management, alter the immunity within the tumour microenvironment. Using glioma-microglia/monocytes transwell co-cultures, we investigated modulatory action of Dex/TMZ on paired Siglecs. Based on real-time PCR and flow cytometry, we found changes in SIGLEC genes and their products. These effects were accompanied by altered cytokine profile and immune cells phenotype switching measured by arginases expression. Additionally, the exposure to Dex or TMZ increased the binding of inhibitory Siglec-5 and Siglec-11 fusion proteins to glioma cells. Our study suggests that the therapy-induced modulation of the interplay between sialoglycans and paired Siglecs, dependently on patient's phenotype, is of particular signification in the immune surveillance in the glioma management and may be useful in glioma patient's therapy plan verification.

Steroid-Functionalized Imidazolium Salts with an Extended Spectrum of Antifungal and Antibacterial Activity.

It is established that high rates of morbidity and mortality caused by fungal infections are related to the current limited number of antifungal drugs and the toxicity of these agents. Imidazolium salts as azole derivatives can be successfully used in the treatment of fungal infections in humans. Steroid-functionalized imidazolium salts were synthesized using a new, more efficient method. As a result, 20 salts were obtained with high yields, 12 of which were synthesized and characterized for the first time. They were derivatives of lithocholic acid and 3-oxo-23,24-dinorchol-4-ene-22-al and were fully characterized by 1H and 13C nuclear magnetic resonance (NMR), infrared spectroscopy (IR), and high resolution mass spectrometry (HRMS). Due to the excellent activity against bacteria and Candida albicans, new research was extended to include tests on five species of pathogenic fungi and molds: Aspergillus niger ATCC 16888, Aspergillus fumigatus ATCC 204305, Trichophyton mentagrophytes ATCC 9533, Cryptococcus neoformans ATCC 14116, and Microsporum canis ATCC 11621. The results showed that the new salts are almost universal antifungal agents and have a broad spectrum of activity against other human pathogens. To initially assess the safety of the synthesized salts, hemocompatibility with host cells and cytotoxicity were also examined. No toxicity was observed at the concentration at which the compounds were active against pathogens.

Magnetic Particles with Polymeric Shells Bearing Cholesterol Moieties Sensitize Breast Cancer Cells to Low Doses of Doxorubicin.

One of the promising strategies for improvement of cancer treatment is application of a combination therapy. The aim of this study was to investigate the anticancer activity of nanoformulations containing doxorubicin and iron oxide particles covered with polymeric shells bearing cholesterol moieties. It was postulated that due to high affinity to cell membranes, particles comprising poly(cholesteryl acrylate) can sensitize cancer cells to doxorubicin chemotherapy. The performed analyses revealed that the developed systems are effective against the human breast cancer cell lines MCF-7 and MDA-MB-231 even at low doses of the active compound applied (0.5 µM). Additionally, high compatibility and lack of toxicity of the tested materials against human red blood cells, immune (monocytic THP-1) cells, and cardiomyocyte H9C2(2-1) cells was demonstrated. Synergistic effects observed upon administration of doxorubicin with polymer-iron oxide hybrids comprising poly(cholesteryl acrylate) may provide an opportunity to limit toxicity of the drug and to improve its therapeutic efficiency at the same time.

Botulinum toxin type-A preparations are not the same medications - basic science (Part 1).

Botulinum neurotoxin type A (BoNT/A) formulations are widely used in clinical practice. Although they share a common mechanism of action resulting in presynaptic block in acetylocholine release, their structure and pharmacological properties demonstrate some similarities and many differences. Bioequivalence has been discussed since the onset of the clinical use of BoNT/A. In this review, we provide an update on the studies and compare the molecular structure, mechanisms of action, diffusion and spread, as well as immunogenicity and dose equivalence of onabotulinumtoxinA, abobotulinumtoxinA and incobotulinumtoxinA.

Botulinum toxin type-A preparations are not the same medications - clinical studies (Part 2).

The growing number of Botulinum neurotoxin type A (BoNT/A) preparations on the market has resulted in a search for pharmacological, clinical and pharmacoeconomic differences. Patients are occasionally switched from one botulinum toxin formulation to another. The aim of this paper was to review studies that have made direct comparisons of the three major BoNT/A preparations presently on the market: ona-, abo- and incobotulinumtoxinA. We also review the single medication Class I pivotal and occasionally Class II-IV studies, as well as recommendations and guidelines to show how effective doses have been adopted in well-established indications such as blepharospasm, hemifacial spasm, cervical dystonia and adult spasticity. Neither direct head-to-head studies nor single medication studies between all preparations allow the formation of universal conversion ratios. All preparations should be treated as distinct medications with respect to their summary of product characteristics when used in everyday practice.

Sialic Acid-Siglec Axis as Molecular Checkpoints Targeting of Immune System: Smart Players in Pathology and Conventional Therapy.

The sialic acid-based molecular mimicry in pathogens and malignant cells is a regulatory mechanism that leads to cross-reactivity with host antigens resulting in suppression and tolerance in the immune system. The interplay between sialoglycans and immunoregulatory Siglec receptors promotes foreign antigens hiding and immunosurveillance impairment. Therefore, molecular targeting of immune checkpoints, including sialic acid-Siglec axis, is a promising new field of inflammatory disorders and cancer therapy. However, the conventional drugs used in regular management can interfere with glycome machinery and exert a divergent effect on immune controlling systems. Here, we focus on the known effects of standard therapies on the sialoglycan-Siglec checkpoint and their importance in diagnosis, prediction, and clinical outcomes.

Heterobasidion annosum Induces Apoptosis in DLD-1 Cells and Decreases Colon Cancer Growth in In Vivo Model.

Application of substances from medicinal mushrooms is one of the interesting approaches to improve cancer therapy. In this study, we commenced a new attempt in the field of Heterobasidion annosum (Fr.) Bref. sensu lato to further extend our knowledge on this basidiomycete fungus. For this purpose, analysis of the active substances of Heterobasidion annosum methanolic extract and also its influence on colorectal cancer in terms of in vitro and in vivo experiments were performed. In vivo studies on mice were conducted to verify its acute toxicity and to further affirm its anticancer potential. Results indicated that all the most common substances of best known medicinal mushrooms that are also responsible for their biological activity are present in tested extracts. In vitro tests showed a high hemocompatibility and a significant decrease in viability and proliferation of DLD-1 cells in a concentration-dependent manner of Heterobasidion annosum extract. The studies performed on xenograft model of mice showed lower tendency of tumor growth in the group of mice receiving Heterobasidion annosum extract as well as mild or moderate toxicity. Obtained results suggest beneficial potential of Heterobasidion annosum against colon cancer as cytotoxic agent or as adjuvant anticancer therapy.

Sialic acids as cellular markers of immunomodulatory action of dexamethasone on glioma cells of different immunogenicity.

Glucocorticosteroids, including dexamethasone (Dex), are commonly used to control tumor-induced edema in the brain tumor patients. There are increasing evidences that immunosuppressive action of Dex interferes with immune surveillance resulting in lower patients overall survival; however, the mechanisms underlying these actions remain unclear. Changes in the expression of sialic acids are critical features of many cancers that reduce their immunogenicity and increase viability. Sialoglycans can be recognized by CD33-related Siglecs that negatively regulate the immune response and thereby impair immune surveillance. In this study, we analysed the effect of Dex on cell surface sialylation pattern and recognition of these structures by Siglec-F receptor in poorly immunogenic GL261 and immunogenic SMA560 glioma cells. Relative amount of α2.3-, α2.6- and α2.8-linked sialic acids were detected by Western blot with MAA (Maackia amurensis) and SNA (Sambucus nigra) lectins, and flow cytometry using monoclonal antibody anti-PSA-NCAM. In response to Dex, α2.8 sialylation in both, GL261 and SMA560 was increased, whereas the level of α2.3-linked sialic acids remained unchanged. Moreover, we found the opposite effects of Dex on α2.6 sialylation in poorly immunogenic and immunogenic glioma cells. Furthermore, changes in sialylation pattern were accompanied by dose-dependent effects of Dex on Siglec-F binding to glioma cell membranes as well as decreased α-neuraminidase activity. These results suggest that glucocorticosteroid-induced alterations in cell surface sialylation and Siglecs recognition may dampen anti-tumor immunity, and participate in glioma-promoting process by immune cells. Our study gives new view on corticosteroid therapy in glioma patients.

Artificial Mucin-based Saliva Preparations - Physicochemical and Tribological Properties.

PURPOSE: To create and investigate artificial mucin-based saliva substitutes with properties similar to natural saliva. MATERIALS AND METHODS: Natural saliva and six saliva preparations were tested. Saliva substitutes were made using phosphate buffered saline (PBS) prepared in deionised water or plasma-treated water (PBSPT) with addition of porcine gastric mucin and guar gum or poloxamer 407. A wide range of properties were characterised: physicochemical (changes of pH, conductivity and surface tension over time: 1, 24, 96, 168 h after mixing ingredients), rheological (viscosity and viscoelasticity), tribological (coefficient of friction for titanium alloy Ti-6Al-7Nb kinematic couple) and corrosive (open circuit potential, corrosion potential, polarisation resistance). RESULTS: Saliva preparations based only on mucin had pH, viscosity, coefficient of friction and corrosion parameters similar to those of natural saliva. Guar gum increased the values of viscosity, viscoelasticity and the coefficient of friction. Similar results were obtained for poloxamer 407, whereas it decreased the surface tension of tested preparations. Plasma-treated PBS enhanced the corrosion resistance of saliva substitutes with guar gum and poloxamer 407. CONCLUSION: Among the tested compositions, saliva substitutes based only on mucin were found to have parameters similar to human whole saliva. Mucin saliva preparations may have wide applicability for patients with e.g. xerostomia or patients using a metal prosthesis.