Investigation of the potential effects of estrogen receptor modulators on immune checkpoint molecules.

Immune checkpoints regulate the immune system response. Recent studies suggest that flavonoids, known as phytoestrogens, may inhibit the PD-1/PD-L1 axis. We explored the potential of estrogens and 17 Selective Estrogen Receptor Modulators (SERMs) as inhibiting ligands for immune checkpoint proteins (CTLA-4, PD-L1, PD-1, and CD80). Our docking studies revealed strong binding energy values for quinestrol, quercetin, and bazedoxifene, indicating their potential to inhibit PD-1 and CTLA-4. Quercetin and bazedoxifene, known to modulate EGFR and IL-6R alongside estrogen receptors, can influence the immune checkpoint functionality. We discuss the impact of SERMs on PD-1 and CTLA-4, suggesting that these SERMs could have therapeutic effects through immune checkpoint inhibition. This study highlights the potential of SERMs as inhibitory ligands for immune checkpoint proteins, emphasizing the importance of considering PD-1 and CTLA-4 inhibition when evaluating SERMs as therapeutic agents. Our findings open new avenues for cancer immunotherapy by exploring the interaction between various SERMs and immune checkpoint pathways.

Protein cargo in extracellular vesicles as the key mediator in the progression of cancer.

Exosomes are small vesicles of endosomal origin that are released by almost all cell types, even those that are pathologically altered. Exosomes widely participate in cell-to-cell communication via transferring cargo, including nucleic acids, proteins, and other metabolites, into recipient cells. Tumour-derived exosomes (TDEs) participate in many important molecular pathways and affect various hallmarks of cancer, including fibroblasts activation, modification of the tumour microenvironment (TME), modulation of immune responses, angiogenesis promotion, setting the pre-metastatic niche, enhancing metastatic potential, and affecting therapy sensitivity and resistance. The unique exosome biogenesis, composition, nontoxicity, and ability to target specific tumour cells bring up their use as promising drug carriers and cancer biomarkers. In this review, we focus on the role of exosomes, with an emphasis on their protein cargo, in the key mechanisms promoting cancer progression. We also briefly summarise the mechanism of exosome biogenesis, its structure, protein composition, and potential as a signalling hub in both normal and pathological conditions. Video Abstract.

Short-term autophagy inhibition by autophinib or SAR405 does not alter the effect of cisplatin on ATP production in prostate cancer cells.

OBJECTIVES: Cisplatin is a widely used anticancer drug for the treatment of many solid cancers. DNA damage is thought to be the key mechanism of cisplatin's anticancer activity. However, cisplatin may also affect cellular metabolism. The aim of this study was to determine the effect of cisplatin on the types of ATP production (OXPHOS versus glycolysis) and their rate in prostate cancer cells and to determine the potentially protective effect of autophagy and amino acids during cisplatin treatment. We also wanted to investigate the potential synergy between the metabolic effects of cisplatin on ATP production and the inhibition of autophagy. METHODS: Cisplatin treatment can significantly affect the metabolism of cancer cells. Important metabolic pathways can be altered, leading to changes in energy production and nutrient utilization. Autophagy and amino acid pool modulations can serve as protective mechanisms significantly affecting tumor cell survival under metabolic stress caused by anticancer treatment. By enabling the recycling of amino acids, autophagy helps cancer cells maintain cellular homeostasis and overcome nutrient limitations. Thus, inhibition of autophagy could have a supportive effect on the metabolic effects of cisplatin. RESULTS: After cisplatin treatment, ATP production by way of OXPHOS was significantly decreased in 22Rv1 and PC-3 cells. On the other hand, ATP production by glycolysis was not significantly affected in 22Rv1 cells. DU145 cells with dysfunctional autophagy were the most sensitive to cisplatin treatment and showed the lowest ATP production. However, short-term autophagy inhibition (24h) by autophinib or SAR405 in 22Rv1 and PC-3 cells did not alter the effect of cisplatin on ATP production. Levels of some amino acids (arginine, methionine) significantly affected the fitness of cancer cells. CONCLUSION: Persistent defects of autophagy can affect the metabolic sensitivity of cancer cells due to interference with arginine metabolism. Amino acids contained in the culture medium had an impact on the overall effect of cisplatin (Fig. 3, Ref. 38).

TET protein inhibitors: Potential and limitations.

TET proteins (methylcytosine dioxygenases) play an important role in the regulation of gene expression. Dysregulation of their activity is associated with many serious pathogenic states such as oncological diseases. Regulation of their activity by specific inhibitors could represent a promising therapeutic strategy. Therefore, this review describes various types of TET protein inhibitors in terms of their inhibitory mechanism and possible applicability. The potential and possible limitations of this approach are thoroughly discussed in the context of TET protein functionality in living systems. Furthermore, possible therapeutic strategies based on the inhibition of TET proteins are presented and evaluated, especially in the field of oncological diseases.

Cancer-associated fibroblasts: Mediators of head and neck tumor microenvironment remodeling.

Cancer-associated fibroblasts (CAFs) are involved in critical aspects of head and neck squamous cell carcinoma (HNSCC) pathogenesis, such as the formation of a tumor-permissive extracellular matrix structure, angiogenesis, or immune and metabolic reprogramming of the tumor microenvironment (TME), with implications for metastasis and resistance to radiotherapy and chemotherapy. The pleiotropic effect of CAFs in TME is likely to reflect the heterogeneity and plasticity of their population, with context-dependent effects on carcinogenesis. The specific properties of CAFs provide many targetable molecules that could play an important role in the future therapy of HNSCC. In this review article, we will focus on the role of CAFs in the TME of HNSCC tumors. We will also discuss clinically relevant agents targeting CAFs, their signals, and signaling pathways, which are activated by CAFs in cancer cells, with the potential for repurposing for HNSCC therapy.

Autophagy modulators influence the content of important signalling molecules in PS-positive extracellular vesicles.

Extracellular vesicles (EVs) are important mediators of intercellular communication in the tumour microenvironment. Many studies suggest that cancer cells release higher amounts of EVs exposing phosphatidylserine (PS) at the surface. There are lots of interconnections between EVs biogenesis and autophagy machinery. Modulation of autophagy can probably affect not only the quantity of EVs but also their content, which can deeply influence the resulting pro-tumourigenic or anticancer effect of autophagy modulators. In this study, we found that autophagy modulators autophinib, CPD18, EACC, bafilomycin A1 (BAFA1), 3-hydroxychloroquine (HCQ), rapamycin, NVP-BEZ235, Torin1, and starvation significantly alter the composition of the protein content of phosphatidylserine-positive EVs (PS-EVs) produced by cancer cells. The greatest impact had HCQ, BAFA1, CPD18, and starvation. The most abundant proteins in PS-EVs were proteins typical for extracellular exosomes, cytosol, cytoplasm, and cell surface involved in cell adhesion and angiogenesis. PS-EVs protein content involved mitochondrial proteins and signalling molecules such as SQSTM1 and TGFß1 pro-protein. Interestingly, PS-EVs contained no commonly determined cytokines, such as IL-6, IL-8, GRO-α, MCP-1, RANTES, and GM-CSF, which indicates that secretion of these cytokines is not predominantly mediated through PS-EVs. Nevertheless, the altered protein content of PS-EVs can still participate in the modulation of the fibroblast metabolism and phenotype as p21 was accumulated in fibroblasts influenced by EVs derived from CPD18-treated FaDu cells. The altered protein content of PS-EVs (data are available via ProteomeXchange with identifier PXD037164) also provides information about the cellular compartments and processes that are affected by the applied autophagy modulators. Video Abstract.

Engine shutdown: migrastatic strategies and prevention of metastases.

Most cancer-related deaths among patients with solid tumors are caused by metastases. Migrastatic strategies represent a unique therapeutic approach to prevent all forms of cancer cell migration and invasion. Because the migration machinery has been shown to promote metastatic dissemination, successful migrastatic therapy may reduce the need for high-dose cytotoxic therapies that are currently used to prevent the risk of metastatic dissemination. In this review we focus on anti-invasive and antimetastatic strategies that hold promise for the treatment of solid tumors. The best targets for migrastatic therapy would be those that are required by all forms of motility, such as ATP availability, mitochondrial metabolism, and cytoskeletal dynamics and cell contractility.

Safety assessment and redox status in rats after chronic exposure to cannabidiol and cannabigerol.

Cannabidiol (CBD) and cannabigerol (CBG) are the two main non-psychotropic phytocannabinoids with high application potential in drug development. Both substances are redox-active and are intensively investigated for their cytoprotective and antioxidant action in vitro. In this study, we focused on an in vivo safety evaluation and the effect of CBD and CBG on the redox status in rats in a 90-d experiment. The substances were administered orogastrically in a dose of 0.66 mg synthetic CBD or 0.66 mg/1.33 mg CBG/kg/day. CBD produced no changes in the red or white blood count or biochemical blood parameters in comparison to the control. No deviations in the morphology or histology of the gastrointestinal tract and liver were observed. After 90 d of CBD exposure, a significant improvement in redox status was found in the blood plasma and liver. The concentration of malondialdehyde and carbonylated proteins was reduced compared to the control. In contrast to CBD, total oxidative stress was significantly increased and this was accompanied by an elevated level of malondialdehyde and carbonylated proteins in CBG-treated animals. Hepatotoxic (regressive changes) manifestations, disruption in white cell count, and alterations in the ALT activity, level of creatinine and ionized calcium were also found in CBG-treated animals. Based on liquid chromatography-mass spectrometry analysis, CBD/CBG accumulated in rat tissues (in the liver, brain, muscle, heart, kidney and skin) at a low ng level per gram. Both CBD and CBG molecular structures include a resorcinol moiety. In CBG, there is an extra dimethyloctadienyl structural pattern, which is most likely responsible for the disruption to the redox status and hepatic environment. The results are valuable to further investigation of the effects of CBD on redox status and should contribute towards opening up critical discussion on the applicability of other non-psychotropic cannabinoids.

Johann Gregor Mendel: the victory of statistics over human imagination.

In 2022, we celebrated 200 years since the birth of Johann Gregor Mendel. Although his contributions to science went unrecognized during his lifetime, Mendel not only described the principles of monogenic inheritance but also pioneered the modern way of doing science based on precise experimental data acquisition and evaluation. Novel statistical and algorithmic approaches are now at the center of scientific work, showing that work that is considered marginal in one era can become a mainstream research approach in the next era. The onset of data-driven science caused a shift from hypothesis-testing to hypothesis-generating approaches in science. Mendel is remembered here as a promoter of this approach, and the benefits of big data and statistical approaches are discussed.

Magnetically Driven Self-Degrading Zinc-Containing Cystine Microrobots for Treatment of Prostate Cancer.

Prostate cancer is the most commonly diagnosed tumor disease in men, and its treatment is still a big challenge in standard oncology therapy. Magnetically actuated microrobots represent the most promising technology in modern nanomedicine, offering the advantage of wireless guidance, effective cell penetration, and non-invasive actuation. Here, new biodegradable magnetically actuated zinc/cystine-based microrobots for in situ treatment of prostate cancer cells are reported. The microrobots are fabricated via metal-ion-mediated self-assembly of the amino acid cystine encapsulating superparamagnetic Fe3 O4 nanoparticles (NPs) during the synthesis, which allows their precise manipulation by a rotating magnetic field. Inside the cells, the typical enzymatic reducing environment favors the disassembly of the aminoacidic chemical structure due to the cleavage of cystine disulfide bonds and disruption of non-covalent interactions with the metal ions, as demonstrated by in vitro experiments with reduced nicotinamide adenine dinucleotide (NADH). In this way, the cystine microrobots served for site-specific delivery of Zn2+ ions responsible for tumor cell killing via a "Trojan horse effect". This work presents a new concept of cell internalization exploiting robotic systems' self-degradation, proposing a step forward in non-invasive cancer therapy.

Self-Propelled Magnetic Dendrite-Shaped Microrobots for Photodynamic Prostate Cancer Therapy.

Photocatalytic micromotors that exhibit wireless and controllable motion by light have been extensively explored for cancer treatment by photodynamic therapy (PDT). However, overexpressed glutathione (GSH) in the tumor microenvironment can down-regulate the reactive oxygen species (ROS) level for cancer therapy. Herein, we present dendrite-shaped light-powered hematite microrobots as an effective GSH depletion agent for PDT of prostate cancer cells. These hematite microrobots can display negative phototactic motion under light irradiation and flexible actuation in a defined path controlled by an external magnetic field. Non-contact transportation of micro-sized cells can be achieved by manipulating the microrobot's motion. In addition, the biocompatible microrobots induce GSH depletion and greatly enhance PDT performance. The proposed dendrite-shaped hematite microrobots contribute to developing dual light/magnetic field-powered micromachines for the biomedical field.

Pentamethinium salts suppress key metastatic processes by regulating mitochondrial function and inhibiting dihydroorotate dehydrogenase respiration.

Mitochondria generate energy and building blocks required for cellular growth and function. The notion that mitochondria are not involved in the cancer growth has been challenged in recent years together with the emerging idea of mitochondria as a promising therapeutic target for oncologic diseases. Pentamethinium salts, cyan dyes with positively charged nitrogen on the benzothiazole or indole part of the molecule, were originally designed as mitochondrial probes. In this study, we show that pentamethinium salts have a strong effect on mitochondria, suppressing cancer cell proliferation and migration. This is likely linked to the strong inhibitory effect of the salts on dihydroorotate dehydrogenase (DHODH)-dependent respiration that has a key role in the de novo pyrimidine synthesis pathway. We also show that pentamethinium salts cause oxidative stress, redistribution of mitochondria, and a decrease in mitochondria mass. In conclusion, pentamethinium salts present novel anti-cancer agents worthy of further studies.

New-Generation Heterocyclic Bis-Pentamethinium Salts as Potential Cytostatic Drugs with Dual IL-6R and Mitochondria-Targeting Activity.

IL-6 signaling is involved in the pathogenesis of a number of serious diseases, including chronic inflammation and cancer. Targeting of IL-6 receptor (IL-6R) by small molecules is therefore an intensively studied strategy in cancer treatment. We describe the design, synthesis, and characteristics of two new bis-pentamethinium salts 5 and 6 (meta and para) bearing indole moieties. Molecular docking studies showed that both compounds have the potential to bind IL-6R (free energy of binding -9.5 and -8.1 kcal/mol). The interaction with IL-6R was confirmed using microscale thermophoresis analyses, which revealed that both compounds had strong affinity for the IL-6R (experimentally determined dissociation constants 26.5 ± 2.5 nM and 304 ± 27.6 nM, respectively). In addition, both compounds were cytotoxic for a broad spectrum of cancer cell lines in micromolar concentrations, most likely due to their accumulation in mitochondria and inhibition of mitochondrial respiration. In summary, the structure motif of bis-pentamethinium salts represents a promising starting point for the design of novel multitargeting compounds with the potential to inhibit IL-6 signaling and simultaneously target mitochondrial metabolism in cancer cells.

mRNA Subtype of Cancer-Associated Fibroblasts Significantly Affects Key Characteristics of Head and Neck Cancer Cells.

Head and neck squamous cell carcinomas (HNSCC) belong among severe and highly complex malignant diseases showing a high level of heterogeneity and consequently also a variance in therapeutic response, regardless of clinical stage. Our study implies that the progression of HNSCC may be supported by cancer-associated fibroblasts (CAFs) in the tumour microenvironment (TME) and the heterogeneity of this disease may lie in the level of cooperation between CAFs and epithelial cancer cells, as communication between CAFs and epithelial cancer cells seems to be a key factor for the sustained growth of the tumour mass. In this study, we investigated how CAFs derived from tumours of different mRNA subtypes influence the proliferation of cancer cells and their metabolic and biomechanical reprogramming. We also investigated the clinicopathological significance of the expression of these metabolism-related genes in tissue samples of HNSCC patients to identify a possible gene signature typical for HNSCC progression. We found that the right kind of cooperation between cancer cells and CAFs is needed for tumour growth and progression, and only specific mRNA subtypes can support the growth of primary cancer cells or metastases. Specifically, during coculture, cancer cell colony supporting effect and effect of CAFs on cell stiffness of cancer cells are driven by the mRNA subtype of the tumour from which the CAFs are derived. The degree of colony-forming support is reflected in cancer cell glycolysis levels and lactate shuttle-related transporters.

Non-psychotropic cannabinoids as inhibitors of TET1 protein.

Non-psychotropic cannabinoids (e.g., cannabidiol, cannabinol and cannabigerol) are contained in numerous alimentary and medicinal products. Therefore, predicting and studying their possible side effects, such as changes in DNA methylation, is an important task for assessing the safety of these products. Interference with TET enzymes by chelating ferrous ions can contribute to the altered methylation pattern. All tested cannabinoids displayed a strong affinity for Fe(II) ions. Cannabidiol and cannabinol exhibited potent inhibitory activities (IC50 = 4.8 and 6.27 µM, respectively) towards the TET1 protein, whereas cannabigerol had no effect on the enzyme activity. An in silico molecular docking study revealed marked binding potential within the catalytic cavity for CBD/CBN, but some affinity was also found for CBG, thus the total lack of activity remains unexplained. These results imply that cannabinoids could affect the activity of the TET1 protein not only due to their affinity for Fe(II) but also due to other types of interactions (e.g., hydrophobic interactions and hydrogen bonding).

Cancer cell viscoelasticity measurement by quantitative phase and flow stress induction.

Cell viscoelastic properties are affected by the cell cycle, differentiation, and pathological processes such as malignant transformation. Therefore, evaluation of the mechanical properties of the cells proved to be an approach to obtaining information on the functional state of the cells. Most of the currently used methods for cell mechanophenotyping are limited by low robustness or the need for highly expert operation. In this paper, the system and method for viscoelasticity measurement using shear stress induction by fluid flow is described and tested. Quantitative phase imaging (QPI) is used for image acquisition because this technique enables one to quantify optical path length delays introduced by the sample, thus providing a label-free objective measure of morphology and dynamics. Viscosity and elasticity determination were refined using a new approach based on the linear system model and parametric deconvolution. The proposed method allows high-throughput measurements during live-cell experiments and even through a time lapse, whereby we demonstrated the possibility of simultaneous extraction of shear modulus, viscosity, cell morphology, and QPI-derived cell parameters such as circularity or cell mass. Additionally, the proposed method provides a simple approach to measure cell refractive index with the same setup, which is required for reliable cell height measurement with QPI, an essential parameter for viscoelasticity calculation. Reliability of the proposed viscoelasticity measurement system was tested in several experiments including cell types of different Young/shear modulus and treatment with cytochalasin D or docetaxel, and an agreement with atomic force microscopy was observed. The applicability of the proposed approach was also confirmed by a time-lapse experiment with cytochalasin D washout, whereby an increase of stiffness corresponded to actin repolymerization in time.

Advances in Cancer Metabolism and Tumour Microenvironment.

Cancer represents an extremely complicated ecosystem where cancer cells communicate with non-cancer cells present in the tumour niche through intercellular contacts, paracrine production of bioactive factors and extracellular vesicles, such as exosomes [...].

Metabolic tricks of cancer cells.

One of the characteristics of cancer cells important for tumorigenesis is their metabolic plasticity. Indeed, in various stress conditions, cancer cells can reshape their metabolic pathways to support the increased energy request due to continuous growth and rapid proliferation. Moreover, selective pressures in the tumor microenvironment, such as hypoxia, acidosis, and competition for resources, force cancer cells to adapt by complete reorganization of their metabolism. In this review, we highlight the characteristics of cancer metabolism and discuss its clinical significance, since overcoming metabolic plasticity of cancer cells is a key objective of modern cancer therapeutics and a better understanding of metabolic reprogramming may lead to the identification of possible targets for cancer therapy.