Modifications of Plasma Membrane Organization in Cancer Cells for Targeted Therapy

Identification of modules and key genes associated with breast cancer subtypes through network analysis

Breast cancer is the most common malignancy in women around the world. Intratumor and intertumoral heterogeneity persist in mammary tumors. Therefore, the identification of biomarkers is essential for the treatment of this malignancy. This study analyzed 28,143 genes expressed in 49 breast cancer cell lines using a Weighted Gene Co-expression Network Analysis to determine specific target proteins for Basal A, Basal B, Luminal A, Luminal B, and HER2 ampl breast cancer subtypes. Sixty-five modules were identified, of which five were characterized as having a high correlation with breast cancer subtypes. Genes overexpressed in the tumor were found to participate in the following mechanisms: regulation of the apoptotic process, transcriptional regulation, angiogenesis, signaling, and cellular survival. In particular, we identified the following genes, considered as hubs: IFIT3, an inhibitor of viral and cellular processes; ETS1, a transcription factor involved in cell death and tumorigenesis; ENSG00000259723 lncRNA, expressed in cancers; AL033519.3, a hypothetical gene; and TMEM86A, important for regulating keratinocyte membrane properties, considered as a key in Basal A, Basal B, Luminal A, Luminal B, and HER2 ampl breast cancer subtypes, respectively. The modules and genes identified in this work can be used to identify possible biomarkers or therapeutic targets in different breast cancer subtypes.

Transcriptomic analysis revealed potential regulatory biomarkers and repurposable drugs for breast cancer treatment

Breast cancer (BC) is the most widespread cancer worldwide. Over 2 million new cases of BC were identified in 2020 alone. Despite previous studies, the lack of specific biomarkers and signaling pathways implicated in BC impedes the development of potential therapeutic strategies. We employed several RNAseq datasets to extract differentially expressed genes (DEGs) based on the intersection of all datasets, followed by protein-protein interaction network construction. Using the shared DEGs, we also identified significant gene ontology (GO) and KEGG pathways to understand the signaling pathways involved in BC development. A molecular docking simulation was performed to explore potential interactions between proteins and drugs. The intersection of the four datasets resulted in 146 DEGs common, including AURKB, PLK1, TTK, UBE2C, CDCA8, KIF15, and CDC45 that are significant hub-proteins associated with breastcancer development. These genes are crucial in complement activation, mitotic cytokinesis, aging, and cancer development. We identified key microRNAs (i.e., hsa-miR-16-5p, hsa-miR-1-3p, hsa-miR-147a, hsa-miR-195-5p, and hsa-miR-155-5p) that are associated with aggressive tumor behavior and poor clinical outcomes in BC. Notable transcription factors (TFs) were FOXC1, GATA2, FOXL1, ZNF24 and NR2F6. These biomarkers are involved in regulating cancer cell proliferation, invasion, and migration. Finally, molecular docking suggested Hesperidin, 2-amino-isoxazolopyridines, and NMS-P715 as potential lead compounds against BC progression. We believe that these findings will provide important insight into the BC progression as well as potential biomarkers and drug candidates for therapeutic development.

Data-driven energy landscape reveals critical genes in cancer progression

The evolution of cancer is a complex process characterized by stable states and transitions among them. Studying the dynamic evolution of cancer and revealing the mechanisms of cancer progression based on experimental data is an important topic. In this study, we aim to employ a data-driven energy landscape approach to analyze the dynamic evolution of cancer. We take Kidney renal clear cell carcinoma (KIRC) as an example. From the energy landscape, we introduce two quantitative indicators (transition probability and barrier height) to study critical shifts in KIRC cancer evolution, including cancer onset and progression, and identify critical genes involved in these transitions. Our results successfully identify crucial genes that either promote or inhibit these transition processes in KIRC. We also conduct a comprehensive biological function analysis on these genes, validating the accuracy and reliability of our predictions. This work has implications for discovering new biomarkers, drug targets, and cancer treatment strategies in KIRC.

Tension-induced adhesion mode switching: the interplay between focal adhesions and clathrin-containing adhesion complexes

Integrin-based adhesion complexes are crucial in various cellular processes, including proliferation, differentiation, and motility. While the dynamics of canonical focal adhesion complexes (FAs) have been extensively studied, the regulation and physiological implications of the recently identified clathrin-containing adhesion complexes (CCACs) are still not well understood. In this study, we investigated the spatiotemporal mechanoregulations of FAs and CCACs in a breast cancer model. Employing single-molecule force spectroscopy coupled with live-cell fluorescence microscopy, we discovered that FAs and CCACs are mutually exclusive and inversely regulated complexes. This regulation is orchestrated through the modulation of plasma membrane tension, in combination with distinct modes of actomyosin contractility that can either synergize with or counteract this modulation. Our findings indicate that increased membrane tension promotes the association of CCACs at integrin αVβ5 adhesion sites, leading to decreased cancer cell proliferation, spreading, and migration. Conversely, lower membrane tension promotes the formation of FAs, which correlates with the softer membranes observed in cancer cells, thus potentially facilitating cancer progression. Our research provides novel insights into the biomechanical regulation of CCACs and FAs, revealing their critical and contrasting roles in modulating cancer cell progression.

Comparative membrane lipidomics of hepatocellular carcinoma cells reveals diacylglycerol and ceramide as key regulators of Wnt/β-catenin signaling and tumor growth

Hepatocellular carcinoma (HCC) is largely associated with aberrant activation of Wnt/β-catenin signaling. Nevertheless, how membrane lipid composition is altered in HCC cells with abnormal Wnt signaling remains elusive. Here, by exploiting comprehensive lipidome profiling, we unravel the membrane lipid composition of six different HCC cell lines with mutations in components of Wnt/β-catenin signaling, leading to differences in their endogenous signaling activity. Among the differentially regulated lipids are diacylglycerol (DAG) and ceramide, which were downregulated at the membrane of HCC cells after Wnt3a treatment. DAG and ceramide enhanced Wnt/β-catenin signaling by inducing caveolin-mediated endocytosis of the canonical Wnt-receptor complex, while their depletion suppressed the signaling activity along with a reduction of caveolin-mediated endocytosis in SNU475 and HepG2 cells. Moreover, depletion of DAG and ceramide significantly impeded the proliferation, tumor growth, and in vivo migration capacity of SNU475 and HepG2 cells. This study, by pioneering plasma membrane lipidome profiling in HCC cells, exhibits the remarkable potential of lipids to correct dysregulated signaling pathways in cancer and stop abnormal tumor growth.

Progress in controllable bioorthogonal catalysis for prodrug activation

Bioorthogonal catalysis, a class of catalytic reactions that are mediated by abiotic metals and proceed in biological environments without interfering with native biochemical reactions, has gained ever-increasing momentum in prodrug delivery over the past few decades. Albeit great progress has been attained in developing new bioorthogonal catalytic reactions and optimizing the catalytic performance of transition metal catalysts (TMCs), the use of TMCs to activate chemotherapeutics at the site of interest in vivo remains a challenging endeavor. To translate the bioorthogonal catalysis-mediated prodrug activation paradigm from flasks to animals, TMCs with targeting capability and stimulus-responsive behavior have been well-designed to perform chemical transformations in a controlled manner within highly complex biochemical systems, rendering on-demand drug activation to mitigate off-target toxicity. Here, we review the recent advances in the development of controllable bioorthogonal catalysis systems, with an emphasis on different strategies for engineering TMCs to achieve precise control over prodrug activation. Furthermore, we outline the envisaged challenges and discuss future directions of controllable bioorthogonal catalysis for disease therapy.

Enhanced Cell Viability and Migration of Primary Bovine Annular Fibrosus Fibroblast-like Cells Induced by Microsecond Pulsed Electric Field Exposure

This study is the first to report the enhancement of cell migration and proliferation induced by in vitro microsecond pulsed electric field (μsPEF) exposure of primary bovine annulus fibrosus (AF) fibroblast-like cells. AF primary cells isolated from fresh bovine intervertebral disks (IVDs) are exposed to 10 and 100 μsPEFs with different numbers of pulses and applied electric field strengths. The results indicate that 10 μs-duration pulses induce reversible electroporation, while 100 μs pulses induce irreversible electroporation of the cells. Additionally, μsPEF exposure increased AF cell proliferation up to 150% while increasing the average migration speed by 0.08 μm/min over 24 h. The findings suggest that the effects of PEF exposure on cells are multifactorial-depending on the duration, intensity, and number of pulses used in the stimulation. This highlights the importance of optimizing the μsPEF parameters for specific cell types and applications. For instance, if the goal is to induce cell death for cancer treatment, then high numbers of pulses can be used to maximize the lethal effects. On the other hand, if the goal is to enhance cell proliferation, a combination of the number of pulses and the applied electric field strength can be tuned to achieve the desired outcome. The information gleaned from this study can be applied in the future to in vitro cell culture expansion and tissue regeneration.

CrMP-Sol database: classification, bioinformatic analyses and comparison of cancer-related membrane proteins and their water-soluble variant designs

Membrane proteins are critical mediators for tumor progression and present enormous therapeutic potentials. Although gene profiling can identify their cancer-specific signatures, systematic correlations between protein functions and tumor-related mechanisms are still unclear. We present here the CrMP-Sol database ( https://bio-gateway.aigene.org.cn/g/CrMP ), which aims to breach the gap between the two. Machine learning was used to extract key functional descriptions for protein visualization in the 3D-space, where spatial distributions provide function-based predictive connections between proteins and cancer types. CrMP-Sol also presents QTY-enabled water-soluble designs to facilitate native membrane protein studies despite natural hydrophobicity. Five examples with varying transmembrane helices in different categories were used to demonstrate the feasibility. Native and redesigned proteins exhibited highly similar characteristics, predicted structures and binding pockets, and slightly different docking poses against known ligands, although task-specific designs are still required for proteins more susceptible to internal hydrogen bond formations. The database can accelerate therapeutic developments and biotechnological applications of cancer-related membrane proteins.

Perturbing plasma membrane lipid: a new paradigm for tumor nanotherapeutics

Cancer is generally considered a result of genetic mutations that cause epigenetic changes, leading to anomalous cellular behavior. Since 1970s, an increasing understanding of the plasma membrane and specifically the lipid alterations in tumor cells have provided novel insights for cancer therapy. Moreover, the advances in nanotechnology offer a potential opportunity to target the tumor plasma membrane while minimizing side effects on normal cells. To further develop membrane lipid perturbing tumor therapy, the first section of this review demonstrates the association between plasma membrane physicochemical properties and tumor signaling, metastasis, and drug resistance. The second section highlights existing nanotherapeutic strategies for membrane disruption, including lipid peroxide accumulation, cholesterol regulation, membrane structure disruption, lipid raft immobilization, and energy-mediated plasma membrane perturbation. Finally, the third section evaluates the prospects and challenges of plasma membrane lipid perturbing therapy as a therapeutic strategy for cancers. The reviewed membrane lipid perturbing tumor therapy strategies are expected to bring about necessary changes in tumor therapy in the coming decades.

Antimicrobial, cytotoxic, and insulin-releasing activities of the amphibian host-defense peptide ocellatin-3N and its L-lysine-substituted analogs

The host-defense peptide ocellatin-3N (GIFDVLKNLAKGVITSLAS.NH₂ ), first isolated from the Caribbean frog Leptodactylus nesiotus, inhibited growth of clinically relevant Gram-positive and Gram-negative bacteria as well as a strain of the major emerging yeast pathogen Candida parapsilosis. Increasing cationicity while maintaining amphipathicity by the substitution Asp⁴ →Lys increased potency against the microorganisms by between 4- and 16-fold (MIC ≤3 μM) compared with the naturally occurring peptide. The substitution Ala¹⁸ →Lys and the double substitution Asp⁴ →Lys and Ala¹⁸ →Lys had less effects on potency. The [D4K] analog also showed 2.5- to 4-fold greater cytotoxic potency against non-small-cell lung adenocarcinoma A549 cells, breast adenocarcinoma MDA-MB-231 cells, and colorectal adenocarcinoma HT-29 cells (LC₅₀ values in the range of 12-20 μM) compared with ocellatin-3N but was less hemolytic to mouse erythrocytes. However, the peptide showed no selectivity for tumor-derived cells [LC₅₀  = 20 μM for human umbilical vein endothelial cells (HUVECs)]. Ocellatin-3N and [D4K]ocellatin-3N stimulated the release of insulin from BRIN-BD11 clonal β-cells at concentrations ≥1 nM, and [A18K]ocellatin-3N, at concentrations ≥0.1 nM. No peptide stimulated the release of lactate dehydrogenase at concentrations up to 3 μM, indicating that plasma membrane integrity had been preserved. The three peptides produced an increase in intracellular [Ca²⁺ ] in BRIN-BD11 cells when incubated at a concentration of 1 μM. In view of its high insulinotropic potency and relatively low hemolytic activity, the [A18K] ocellatin analog may represent a template for the design of agents with therapeutic potential for the treatment of patients with type 2 diabetes.

The Anti-Inflammatory Activity of Viscum album

The therapeutic story of European mistletoe (Viscum album L.) presents a seesawing profile. In ancient times, this hemiparasitic plant was considered a panacea and even to be endowed with exceptional beneficial properties. In more recent times, despite its multiple uses in traditional medicines, some parts of the plant, in particular the berries, were considered poisonous and dangerous, including concerns of cytotoxicity, which spread serious suspicion on its medicinal utility. However, since the last century, medical interest in mistletoe has come back in force due to its utilization in clinical cancer treatments, based on its selective action on tumor cells. In Central Europe, the hydro-alcoholic extracts of European mistletoe register a relevant and continuous utilization in anthroposophic medicine, which is a holistic system that includes the utilization of phytomedicinal substances. In Switzerland and Germany, most physicians and patients use these products as complementary therapy in oncological treatments. However, despite its increasing use in this field, the results of mistletoe's use are not always convincing, and other aspects have appeared. Nowadays, products that contain mistletoe are utilized in several fields, including diet, phytotherapy, veterinary medicine and homeopathy, but in particular in cancer therapies as coadjuvant factors, in consideration of several positive effects including effects in the improvement of quality-of-life conditions and reinforcement of the immune system. In this review, based on the understanding of the association between cancer and inflammation, we propose a relationship between these recent uses of mistletoe, based on its antioxidant properties, which are supported by phytochemical and pharmacological data. The unicity of mistletoe metabolism, which is a direct consequence of its hemiparasitism, is utilized as a key interpretation element to explain its biological properties and steer its consequent therapeutic uses.

Aggregation-Induced Emission Luminogens for Enhanced Photodynamic Therapy: From Organelle Targeting to Tumor Targeting

Photodynamic therapy (PDT) has attracted much attention in the field of anticancer treatment. However, PDT has to face challenges, such as aggregation caused by quenching of reactive oxygen species (ROS), and short ¹O₂ lifetime, which lead to unsatisfactory therapeutic effect. Aggregation-induced emission luminogen (AIEgens)-based photosensitizers (PSs) showed enhanced ROS generation upon aggregation, which showed great potential for hypoxic tumor treatment with enhanced PDT effect. In this review, we summarized the design strategies and applications of AIEgen-based PSs with improved PDT efficacy since 2019. Firstly, we introduce the research background and some basic knowledge in the related field. Secondly, the recent approaches of AIEgen-based PSs for enhanced PDT are summarized in two categories: (1) organelle-targeting PSs that could cause direct damage to organelles to enhance PDT effects, and (2) PSs with tumor-targeting abilities to selectively suppress tumor growth and reduce side effects. Finally, current challenges and future opportunities are discussed. We hope this review can offer new insights and inspirations for the development of AIEgen-based PSs for better PDT effect.

Evidence of Metallic and Polyether Ionophores as Potent Therapeutic Drug Candidate in Cancer Management

Cancer remains one of the most crucial human malignancies with a higher mortality rate globally, and is predicted to escalate soon. Dysregulated ion homeostasis in cancerous cells prompted the researchers to investigate further ion homeostasis impeding agents as potent anticancerous agents. Reutilization of FDA-approved non-cancerous drugs has emerged as a practical approach to developing potent, cost-effective drugs for cancer treatment. Across the globe, most nations are incapable of fulfilling the medical demands of cancer patients due to costlier cancerous drugs. Therefore, we have inclined our review towards emphasizing recent advancements in cancer therapies involving ionophores utilization in exploring potent anticancer drugs. Numerous research reports have established the significant anticancerous potential of ionophores in several pre-clinical reports via modulating aberrant cell signaling pathways and enhancing antitumor immunity in immune cells. This review has mainly summarized the most significant ion homeostasis impeding agents, including copper, zinc, calcium, and polyether, that presented remarkable potential in cancer therapeutics via enhanced antitumor immunity and apoptosis induction. Altogether, this study could provide a robust future perspective for developing cost-effective anticancerous drugs rapidly and cost-effectively, thereby combating the limitations of currently available drugs used in cancer treatment.

RCCS Bioreactor-Based Modeled Microgravity Affects Gastric Cancer Cells and Improves the Chemotherapeutic Effect

(1) Background: The main purpose of the study was to determine whether altered gravity might alter cell viability, improve drug delivery and modulate the expression of drug resistance-related genes. (2) Methods: This study investigated the intracellular mechanisms activated by microgravity in human resistant and sensitive gastric cancer cells (EPG85-257 RDB) and (EPG85-257 P). We used a rotary cell culture system (RCCS) developed by NASA to expose cells to altered gravity. The antitumor potential of microgravity was simulated by the RCCS bioreactor, and its effectiveness was evaluated in sensitive cell lines compared to chemotherapy-resistant cells concerning drug-sensitive cancer cells. Microgravity with chemotherapy was estimated by the viability assay, cytoskeleton imaging, MDR (multidrug resistance) gene expression analysis, MTCO-1 (mitochondrially encoded cytochrome C oxidase I), and 8-OHdG immunocytochemical analysis. (3) Results: We found that altered gravity combined with doxorubicin was cytotoxic to cancer cells. Cells following simulated microgravity revealed decreased expression of genes related to drug resistance and increased DNA/RNA damage marker expression. Cytoskeleton evaluation demonstrated significant reorganization of F-actin fibers after exposure to changed gravity conditions. (4) Conclusions: Intracellular alterations caused by simulated microgravity can increase gastric cancer cells’ sensitivity to chemotherapy. We have obtained satisfactory results showing the correlation between altered gravity and MDR phenomena which seems promising in future therapeutic applications.

Micro- and Nanosecond Pulses Used in Doxorubicin Electrochemotherapy in Human Breast and Colon Cancer Cells with Drug Resistance

(1) Background: Pulsed electric field (PEF) techniques are commonly used to support the delivery of various molecules. A PEF seems a promising method for low permeability drugs or when cells demonstrate therapy resistance and the cell membrane becomes an impermeable barrier. (2) Methods: In this study, we have used doxorubicin-resistant and sensitive models of human breast cancer (MCF-7/DX, MCF-7/WT) and colon cancer cells (LoVo, LoVoDX). The study aimed to investigate the susceptibility of the cells to doxorubicin (DOX) and electric fields in the 20–900 ns pulse duration range. The viability assay was utilized to evaluate the PEF protocols’ efficacy. Cell confluency and reduced glutathione were measured after PEF protocols. (3) Results: The obtained results showed that PEFs significantly supported doxorubicin delivery and cytotoxicity after 48 and 72 h. The 60 kV/cm ultrashort pulses × 20 ns × 400 had the most significant cytotoxic anticancer effect. The increase in DOX concentration provokes a decrease in cell viability, affected cell confluency, and reduced GSSH when combined with the ESOPE (European Standard Operating Procedures of Electrochemotherapy) protocol. Additionally, reactive oxygen species after PEF and PEF-DOX were detected. (4) Conclusions: Ultrashort electric pulses with low DOX content or ESOPE with higher DOX content seem the most promising in colon and breast cancer treatment.

Human β-Defensin 2 (HBD-2) Displays Oncolytic Activity but Does Not Affect Tumour Cell Migration

Defensins form an integral part of the cationic host defence peptide (HDP) family, a key component of innate immunity. Apart from their antimicrobial and immunomodulatory activities, many HDPs exert multifaceted effects on tumour cells, notably direct oncolysis and/or inhibition of tumour cell migration. Therefore, HDPs have been explored as promising anticancer therapeutics. Human β-defensin 2 (HBD-2) represents a prominent member of human HDPs, being well-characterised for its potent pathogen-killing, wound-healing, cytokine-inducing and leukocyte-chemoattracting functions. However, its anticancer effects remain largely unknown. Recently, we demonstrated that HBD-2 binds strongly to phosphatidylinositol-4,5-bisphosphate (PI(4,5)P₂), a key mediator of defensin-induced cell death and an instructional messenger during cell migration. Hence, in this study, we sought to investigate the lytic and anti-migratory effects of HBD-2 on tumour cells. Using various cell biological assays and confocal microscopy, we showed that HBD-2 killed tumour cells via acute lytic cell death rather than apoptosis. In addition, our data suggested that, despite the reported PI(4,5)P₂ interaction, HBD-2 does not affect cytoskeletal-dependent tumour cell migration. Together, our findings provide further insights into defensin biology and informs future defensin-based drug development.

Ultrasound-Enabled Therapeutic Delivery and Regenerative Medicine: Physical and Biological Perspectives

The role of ultrasound in medicine and biological sciences is expanding rapidly beyond its use in conventional diagnostic imaging. Numerous studies have reported the effects of ultrasound on cellular and tissue physiology. Advances in instrumentation and electronics have enabled successful in vivo applications of therapeutic ultrasound. Despite path breaking advances in understanding the biophysical and biological mechanisms at both microscopic and macroscopic scales, there remain substantial gaps. With the progression of research in this area, it is important to take stock of the current understanding of the field and to highlight important areas for future work. We present herein key developments in the biological applications of ultrasound especially in the context of nanoparticle delivery, drug delivery, and regenerative medicine. We conclude with a brief perspective on the current promise, limitations, and future directions for interfacing ultrasound technology with biological systems, which could provide guidance for future investigations in this interdisciplinary area.

The Impact of Extracellular Ca2+ and Nanosecond Electric Pulses on Sensitive and Drug-Resistant Human Breast and Colon Cancer Cells

Simple Summary

The drug resistance phenomenon in cancer constantly induces problems in therapeutic protocols. Pulsed electric fields (PEFs) seem to be a promising method in drug molecule delivery. Here we have proved that electroporation supported by calcium ions can alternate the activity of drug resistance proteins. Our results indicated that MDR1 expression is not significantly modified by nanosecond electroporation in multidrug-resistant cells. However, PEF significantly inhibited MDR1 activity and cell viability when combined with calcium ions.

Abstract

(1) Background: Calcium electroporation (CaEP) is based on the application of electrical pulses to permeabilize cells (electroporation) and allow cytotoxic doses of calcium to enter the cell. (2) Methods: In this work, we have used doxorubicin-resistant (DX) and non-resistant models of human breast cancer (MCF-7/DX, MCF-7/WT) and colon cancer cells (LoVo, LoVo/DX), and investigated the susceptibility of the cells to extracellular Ca²⁺ and electric fields in the 20 ns–900 ns pulse duration range. (3) Results: We have observed that colon cancer cells were less susceptible to PEF than breast cancer cells. An extracellular Ca²⁺ (2 mM) with PEF was more disruptive for DX-resistant cells. The expression of glycoprotein P (MDR1, P-gp) as a drug resistance marker was detected by the immunofluorescent (CLSM) method and rhodamine-123 efflux as an MDR1 activity. MDR1 expression was not significantly modified by nanosecond electroporation in multidrug-resistant cells, but a combination with calcium ions significantly inhibited MDR1 activity and cell viability. (4) Conclusions: We believe that PEF with calcium ions can reduce drug resistance by inhibiting drug efflux activity. This phenomenon of MDR mechanism disruption seems promising in anticancer protocols.