Advances in targeting epidermal growth factor receptor signaling pathway in mammary cancer

Estrogen Receptor-α Exacerbates EGF-Inducing Airway Remodeling and Mucus Production in Bronchial Epithelium of Asthmatics

PURPOSE

Although estrogen receptors (ERs) signal pathways are involved in the pathogenesis and development of asthma, their expressions and effects remain controversial. This study aimed to investigate the expressions of ERα and ERβ as well as their mechanisms in airway remodeling and mucus production in asthma.

METHODS

The expressions of ERα and ERβ in the airway epithelial cells of bronchial biopsies and induced sputum cells were examined by immunohistochemistry. The associations of ERs expressions with airway inflammation and remodeling were evaluated in asthmatic patients. In vitro, the regulations of ERs expressions in human bronchial epithelial cell lines were examined using western blot analysis. The epidermal growth factor (EGF)-mediated ligand-independent activation of ERα and its effect on epithelial-mesenchymal transitions (EMTs) were investigated in asthmatic epithelial cells by western blot, immunofluorescent staining, and quantitative real-time polymerase chain reaction.

RESULTS

ERα and ERβ were expressed on both bronchial epithelial cells and induced sputum cells, and the expressions showed no sex difference. Compared to controls, male asthmatic patients had higher levels of ERα on the bronchial epithelium, and there were cell-specific expressions of ERα and ERβ in induced sputum. The expression of ERα in the airway epithelium was inversely correlated to forced expiratory volume in 1 second (FEV1) % and FEV1/forced vital capacity. Severe asthmatic patients had significantly greater levels of ERα in the airway epithelium than mild-moderate patients. ERα level was positively correlated with the thickness of the subepithelial basement membrane and airway epithelium. In vitro, co-stimulation of interleukin (IL)-4 and EGF increased the expression of ERα and promoted its nuclear translocation. EGF activated the phosphorylation of ERα via extracellular signal-regulated kinase and c-Jun N-terminal kinase pathways. ERα knockdown alleviated EGF-mediated EMTs and mucus production in airway epithelial cells of asthma.

CONCLUSIONS

ERα contributes to asthmatic airway remodeling and mucus production through the EGF-mediated ligand-independent pathway.

Design, synthesis, anticancer evaluation, and in silico studies of some thieno[2,3-d]pyrimidine derivatives as EGFR inhibitors

New series of 20 thieno[2,3-d]pyrimidine derivatives have been synthesized. The National Cancer Institute evaluated all the newly synthesized compounds for their antiproliferative activity against a panel of 60 cancer cell lines. Compound 7b exhibited a remarkable antineoplastic activity at 10 µM dose and was therefore tested at five dose concentrations. The significant and broad-spectrum antineoplastic action of compound 7b was observed against 37 of the tested cancer cell lines with a dose that inhibits 50% of the growth compared to control values in the micromolar range of 1.95-9.6 µM. The dose which inhibits the growth completely in the cytostatic range of 3.99-100 µM was also observed. Compound 7b effectively inhibited epidermal growth factor receptor (EGFR) with 50% inhibition concentration value (IC50 ) = 0.096 ± 0.004 compared to erlotinib with IC50  = 0.037 ± 0.002. Moreover, compound 7b revealed a powerful downregulation effect on total EGFR concentration and its phosphorylation. In addition, compound 7b inhibited phosphatidylinositol 3-kinase, protein kinase B, and the mammalian target of rapamycin pathway phosphorylation. Furthermore, compound 7b raised total apoptosis by 21.93-fold in the ovarian cancer cell line (OVCAR-4) and caused an arrest in the cell cycle in the G1/S phase. It also raised the level of caspase-3 by 4.72-fold. Furthermore, to determine the binding manner of the most effective derivatives and validate their capacity to comply with the pharmacophoric properties necessary for EGFR inhibition, they were docked into the active site of the EGFR.

Effects of saponins from Chinese herbal medicines on signal transduction pathways in cancer: A review

Cancer poses a serious threat to human health, and the search for safe and effective drugs for its treatment has aroused interest and become a long-term goal. Traditional Chinese herbal medicine (TCM), an ancient science with unique anti-cancer advantages, has achieved outstanding results in long-term clinical practice. Accumulating evidence shows that saponins are key bioactive components in TCM and have great research and development applications for their significant role in the treatment of cancer. Saponins are a class of glycosides comprising nonpolar triterpenes or sterols attached to hydrophilic oligosaccharide groups that exert antitumor effects by targeting the NF-κB, PI3Ks-Akt-mTOR, MAPK, Wnt-β-catenin, JAK-STAT3, APMK, p53, and EGFR signaling pathways. Presently, few advances have been made in physiological and pathological studies on the effect of saponins on signal transduction pathways involved in cancer treatment. This paper reviews the phytochemistry and extraction methods of saponins of TCM and their effects on signal transduction pathways in cancer. It aims to provide theoretical support for in-depth studies on the anticancer effects of saponins.

Biological Activity of Oleanolic Acid Derivatives HIMOXOL and Br-HIMOLID in Breast Cancer Cells Is Mediated by ER and EGFR

Breast cancer is one of the most frequently observed malignancies worldwide and represents a heterogeneous group of cancers. For this reason, it is crucial to properly diagnose every single case so a specific and efficient therapy can be adjusted. One of the most critical diagnostic parameters evaluated in cancer tissue is the status of the estrogen receptor (ER) and epidermal growth factor receptor (EGFR). Interestingly, the expression of the indicated receptors may be used in a personalized therapy approach. Importantly, the promising role of phytochemicals in the modulation of pathways controlled by ER and EGFR was also demonstrated in several types of cancer. One such biologically active compound is oleanolic acid, but due to poor water solubility and cell membrane permeability that limits its use, alternative derivative compounds were developed. These are HIMOXOL and Br-HIMOLID, which were demonstrated to be capable of inducing apoptosis and autophagy or diminishing the migratory and invasive potential of breast cancer cells in vitro. In our study, we revealed that proliferation, cell cycle, apoptosis, autophagy, and also the migratory potential of HIMOXOL and Br-HIMOLID in breast cancer cells are mediated by ER (MCF7) and EGFR (MDA-MB-231) receptors. These observations make the studied compounds interesting in the context of anticancer strategies.

Synergistic therapeutic potential of alpelisib in cancers (excluding breast cancer): Preclinical and clinical evidences

The phosphoinositide 3-kinase (PI3K) signaling pathway is well-known for its important role in cancer growth, proliferation and migration. The activation of PI3K pathway is always connected with endocrine resistance and poor prognosis in cancers. Alpelisib, a selective inhibitor of PI3K, has been demonstrated to be effective in combination with endocrine therapy in HR+ PIK3CA-mutated advanced breast cancer in preclinical and clinical trials. Recently, the synergistic effects of alpelisib combined with targeted agents have been widely reported in PIK3CA-mutated cancer cells, such as breast, head and neck squamous cell carcinoma (HNSCC), cervical, liver, pancreatic and lung cancer. However, previous reviews mainly focused on the pharmacological activities of alpelisib in breast cancer. The synergistic therapeutic potential of alpelisib in other cancers has not yet been well reviewed. In this review, an extensive study of related literatures (published until December 20, 2022) regarding the anti-cancer functions and synergistic effects of alpelisib was carried out through the databases. Useful information was extracted. We summarized the preclinical and clinical studies of alpelisib in combination with targeted anti-cancer agents in cancer treatment (excluding breast cancer). The combinations of alpelisib and other targeted agents significantly improved the therapeutic efficacy both in preclinical and clinical studies. Unfortunately, synergistic therapies still could not effectively avoid the possible toxicities and adverse events during treatment. Finally, some prospects for the combination studies in cancer treatment were provided in the paper. Taken together, this review provided valuable information for alpelisib in preclinical and clinical applications.

Trends in extracellular matrix biology

Extracellular matrixes (ECMs) are intricate 3-dimensional macromolecular networks of unique architectures with regulatory roles in cell morphology and functionality. As a dynamic native biomaterial, ECM undergoes constant but tightly controlled remodeling that is crucial for the maintenance of normal cellular behavior. Under pathological conditions like cancer, ECM remodeling ceases to be subjected to control resulting in disease initiation and progression. ECM is comprised of a staggering number of molecules that interact not only with one another, but also with neighboring cells via cell surface receptors. Such interactions, too many to tally, are of paramount importance for the identification of novel disease biomarkers and more personalized therapeutic intervention. Recent advances in big data analytics have allowed the development of online databases where researchers can take advantage of a stochastic evaluation of all the possible interactions and narrow them down to only those of interest for their study, respectively. This novel approach addresses the limitations that currently exist in studies, expands our understanding on ECM interactions, and has the potential to advance the development of targeted therapies. In this article we present the current trends in ECM biology research and highlight its importance in tissue integrity, the main interaction networks, ECM-mediated cell functional properties and issues related to pharmacological targeting.

LY2874455 and Abemaciclib Reverse FGF3/4/19/CCND1 Amplification Mediated Gefitinib Resistance in NSCLC

Non-small cell lung carcinoma (NSCLC) patients who initially received tyrosine kinase inhibitor (TKI) therapy often acquired resistance via multiple complex mechanisms. The amplification of FGF3/4/19/CCND1 on chromosome 11q13 was found in many cancers with TKI resistance. However, the role of these amplifications in TKI-resistant NSCLC remains uncovered. Here, we generated the FGF3/4/19/CCND1 amplification model in the NSCLC cell lines PC-9 and HCC827. Upregulation of FGF3/4/19/CCND1 strongly promoted cell proliferation and gefitinib resistance in NSCLC cells. To find out the potential therapeutic strategies, we screened the combination of inhibitors against the FGF/FGFR signaling pathway and the CCND1/CDK4 complex and revealed that gefitinib combined with LY2874455 and abemaciclib exhibited the most effective inhibition of resistance in vitro and in vivo. Mechanistically, FGFs/CCND1 activated the MAPK pathway, which was abolished by the combination drugs. Our study provides a rationale for clinical testing of dual targeting FGFR and CCND1 with LY2874455 and abemaciclib in NSCLC patients who harbored FGF3/4/19/CCND1 amplification.

ESR2 Drives Mesenchymal-to-Epithelial Transition in Triple-Negative Breast Cancer and Tumorigenesis In Vivo

Estrogen receptors (ERs) have pivotal roles in the development and progression of triple-negative breast cancer (TNBC). Interactions among cancer cells and tumor microenvironment are orchestrated by the extracellular matrix that is rapidly emerging as prominent contributor of fundamental processes of breast cancer progression. Early studies have correlated ERβ expression in tumor sites with a more aggressive clinical outcome, however ERβ exact role in the progression of TNBC remains to be elucidated. Herein, we introduce the functional role of ERβ suppression following isolation of monoclonal cell populations of MDA-MB-231 breast cancer cells transfected with shRNA against human ESR2 that permanently resulted in 90% reduction of ERβ mRNA and protein levels. Further, we demonstrate that clone selection results in strongly reduced levels of the aggressive functional properties of MDA-MB-231 cells, by transforming their morphological characteristics, eliminating the mesenchymal-like traits of triple-negative breast cancer cells. Monoclonal populations of shERβ MDA-MB-231 cells undergo universal matrix reorganization and pass on a mesenchymal-to-epithelial transition state. These striking changes are encompassed by the total prevention of tumorigenesis in vivo following ERβ maximum suppression and isolation of monoclonal cell populations in TNBC cells. We propose that these novel findings highlight the promising role of ERβ targeting in future pharmaceutical approaches for managing the metastatic dynamics of TNBC breast cancer.

Endocytosis at the Crossroad of Polarity and Signaling Regulation: Learning from Drosophila melanogaster and Beyond

Cellular trafficking through the endosomal–lysosomal system is essential for the transport of cargo proteins, receptors and lipids from the plasma membrane inside the cells and across membranous organelles. By acting as sorting stations, vesicle compartments direct the fate of their content for degradation, recycling to the membrane or transport to the trans-Golgi network. To effectively communicate with their neighbors, cells need to regulate their compartmentation and guide their signaling machineries to cortical membranes underlying these contact sites. Endosomal trafficking is indispensable for the polarized distribution of fate determinants, adaptors and junctional proteins. Conversely, endocytic machineries cooperate with polarity and scaffolding components to internalize receptors and target them to discrete membrane domains. Depending on the cell and tissue context, receptor endocytosis can terminate signaling responses but can also activate them within endosomes that act as signaling platforms. Therefore, cell homeostasis and responses to environmental cues rely on the dynamic cooperation of endosomal–lysosomal machineries with polarity and signaling cues. This review aims to address advances and emerging concepts on the cooperative regulation of endocytosis, polarity and signaling, primarily in Drosophila melanogaster and discuss some of the open questions across the different cell and tissue types that have not yet been fully explored.

miR9 inhibits 6-mer HA-induced cytokine production and apoptosis in human chondrocytes by reducing NF-kB activation

The present study aimed to investigate the expression of miR9 and its correlation with cytokines, proteolytic enzymes and apoptosis in an experimental model of 6-mer HA induced inflammation in human chondrocytes. Human articular chondrocytes, transfected with a miR-9 mimic and miR-9 inhibitor, were stimulated with 6-mer HA in presence/absence of a specific NF-kB inhibitor. 6-mer HA induced a significant increase of TLR-4, CD44, IL-8, IL-18, MMP-9, ADAMTS-5, BAX and BCL-2 mRNAs expression and the related proteins, as well as NF-kB activation, associated with a significant up regulation of miR-9. In chondrocytes transfected with the miR-9 mimic before 6-mer HA treatment we found a decrease of such inflammatory cytokines, metalloproteases and pro-apoptotic molecules, while we found them increased in chondrocytes transfected with the miR9 inhibitor before 6-mer HA stimulation. The activities of TLR-4 and CD44, up regulated by 6-mer HA, were not modified by miR9 mimic/inhibitor, while the NF-kB activation was significantly affected. We suggested that the up regulation of miR9, induced by 6-mer HA, could be a cellular attempt to limit cell damage during inflammation.

F. Soliman A, Moatasim Y, El Taweel A, Abdelhameed MF, Bekheit MS, Ali MA, Girgis AS. Synthesis of aspirin-curcumin mimic conjugates of potential antitumor and anti-SARS-CoV-2 properties

Series of piperidone-salicylate conjugates were synthesized through the reaction of 3E,5E-bis(arylidene)-4-piperidones with the appropriate acid chloride of acetylsalicylate in the presence of triethylamine. All the synthesized conjugates reveal antiproliferative properties against A431 (squamous skin) cancer cell line with potency higher than that of 5-fluorouracil. Many of the synthesized agents also exhibit promising antiproliferative properties against HCT116 (colon) cancer cell line, of which 5o and 5c are the most effective with 12.9, 9.8 folds potency compared with Sunitinib. Promising activity is also shown against MCF7 (breast) cancer cell line with 1.19, 1.12 folds relative to 5-fluorouracil. PI-flow cytometry of compound 5c supports the arrest of cell cycle at G1-phase. However, compound 5o and Sunitinib arrest the cell cycle at S-phase. The synthesized conjugates can be considered as multi-targeted tyrosine kinase inhibitors due to the promising properties against VEGFR-2 and EGFR in MCF7 and HCT116. CDOCKER studies support the EGFR inhibitory properties. Compounds 5p and 5i possessing thienylidene heterocycle are anti-SARS-CoV-2 with high therapeutic indices. Many of the synthesized agents show enhanced COX-1/2 properties than aspirin with better selectivity index towards COX-2 relative to COX-1. The possible applicability of the potent candidates discovered as antitumor and anti-SARS-CoV-2 is supported by the safe profile against normal (non-cancer, RPE1 and VERO-E6) cells.

EGFR is a pivotal player of the E2/ERβ - mediated functional properties, aggressiveness, and stemness in triple-negative breast cancer cells

Triple-negative breast cancer (TNBC) is defined by aggressive behavior, limited response to chemotherapy and lower overall survival rates. The increased metastatic potential of TNBC is a combined result of extensive extracellular matrix (ECM) remodeling that leads to cytoskeleton rearrangement and activation of epithelial-to-mesenchymal transition (EMT). The overexpression of epidermal growth factor receptor (EGFR) in TNBC tumors has been linked to induced expression of EMT-related molecules. EMT activation has often been associated with increased metastasis and stemness. Recently, we described the crucial role of EGFR/estrogen receptor beta (ERβ) interplay in the regulation of invasion and cell-matrix interactions. In this study, we report on the EGFR-ERβ functional relationship in connection to the aggressiveness and cancer stem cell (CSC)-like characteristics of TNBC cells. ERβ-suppressed and MDA-MB-231 cells were subjected to downstream EGFR inhibition and/or estradiol stimulation to assess alterations in functional parameters as well as in morphological characteristics, studied by scanning electron, atomic force, and immunofluorescence microscopies. Moreover, the expression and localization of key EMT and CSC-related markers were also evaluated by real-time qPCR, immunofluorescence microscopy, and flow cytometry. EGFR inhibition resulted in an overall suppression of aggressive functional characteristics, which occurred in an ERβ-mediated manner. These changes could be attributed to a reduction, at the molecular level, of EMT and stemness-linked markers, most notably reduced expression of Notch signaling constituents and the cell surface proteoglycan, syndecan-1. Collectively, our study highlights the importance of EGFR signaling as a key effector of aggressiveness, EMT, and stemness in an ERβ-dependent way in TNBC.

Faciogenital Dysplasia 5 supports cancer stem cell traits in basal-like breast cancer by enhancing EGFR stability

Most basal-like breast cancers (BLBCs) are triple-negative breast cancers (TNBCs), which have the worst prognosis and distant metastasis-free survival among breast cancer subtypes. Now, no targeted therapies are available for patients with BLBC due to the lack of reliable and effective molecular targets. Here, we performed the BLBC tissue microarray-based immunohistochemical analysis and showed that Faciogenital Dysplasia 5 (FGD5) abundance is associated with poor prognosis in BLBCs. FGD5 deletion decreased the proliferation, invasion, and tumorsphere formation capacity of BLBC cells. Furthermore, genetic inhibition of Fgd5 in mouse mammary epithelial cells attenuated BLBC initiation and progression by reducing the self-renewal ability of tumor-initiating cells. In addition, FGD5 abundance was positively correlated with the abundance of epidermal growth factor receptor (EGFR) in BLBCs. FGD5 ablation decreased EGFR abundance by reducing EGFR stability in TNBC cells in 2D and 3D culture conditions. Mechanistically, FGD5 binds to EGFR and interferes with basal EGFR ubiquitination and degradation induced by the E3 ligase ITCH. Impaired EGFR degradation caused BLBC cell proliferation and promoted invasive properties and self-renewal. To verify the role of the FGD5-EGFR interaction in the regulation of EGFR stability, we screened a cell-penetrating α-helical peptide PER3 binding with FGD5 to disrupt the interaction. Treatment of BLBC patient-derived xenograft-bearing mice with the peptide PER3 disrupting the FGD5-EGFR interaction either with or without chemotherapy reduced BLBC progression. Our study identified FGD5 as a positive modulator of tumor-initiating cells and suggests a potential therapeutic option for the BLBC subtype of breast cancer.

Pyrimidine-based EGFR TK inhibitors in targeted cancer therapy

Despite significant improvements of new treatment options, cancer continues to represent as one of the most common and fatal disease. The EGFR signaling pathway is considered as a significant approach in targeted therapy of cancers. Blocking the EGFR-driven pathway by inhibiting the intracellular tyrosine kinase domain of EGFR have shown considerable improvement in cancer therapy. In an effort to identify EGFR tyrosine kinase inhibitors (TKI), several small molecules especially pyrimidine containing derivatives have been designed by applying molecular simulation and evaluated the emergence of epigenetic mutation and resistance problems restricted the long-term effectiveness of such medication and explained the need for further investigations in this field. In recent years, the studies have been focused on genetic alterations on EGFR tyrosine kinase domain, which led to the design and synthesis of more selective and effective inhibitors. Herein, we give an overview of the importance and status of EGFR inhibitors in cancer therapy. In addition, we provide an update of the recent advances in design, discovery and development of novel pyrimidine containing compounds as promising selective EGFR TK inhibitors.

Design, Synthesis, In Silico and In Vitro Evaluation of Novel Pyrimidine Derivatives as EGFR Inhibitors

BACKGROUND

The abnormal signaling from tyrosine kinase causes many types of cancers, including breast cancer, non-small cell lung cancer, and chronic myeloid leukemia. This research reports the in silico, synthesis, and in vitro study of novel pyrimidine derivatives as EGFR inhibitors.

OBJECTIVE

The objective of the research study is to discover more promising lead compounds using the drug discovery process, in which a rational drug design is achieved by molecular docking and virtual pharmacokinetic studies.

METHODS

The molecular docking studies were carried out using discovery studio 3.5-version software. The molecules with good docking and binding energy score were synthesized, and their structures were confirmed by FT-IR, NMR, Mass and elemental analysis. Subsequently, molecules were evaluated for their anti-cancer activity using MDA-MB-231, MCF-7, and A431 breast cancer cell lines by MTT and tyrosine kinase assay methodology.

RESULTS

Pyrimidine derivatives displayed anti-cancer activity. Particularly, compound R8 showed significant cytotoxicity against MDA-MB-231 with an IC50 value of 18.5±0.6μM. Molecular docking studies proved that the compound R8 has good binding fitting by forming hydrogen bonds with amino acid residues at ATP binding sites of EGFR.

CONCLUSION

Eight pyrimidine derivatives were designed, synthesized, and evaluated against breast cancer cell lines. Compound R8 significantly inhibited the growth of MDA-MB-231 and MCF-7. Molecular docking studies revealed that compound R8 has good fitting by forming different Hydrogen bonding interactions with amino acids at the ATP binding site of epidermal growth factor receptor target. Compound R8 was a promising lead molecule that showed better results as compared to other compounds in in vitro studies.

EGFR targeting for cancer therapy: Pharmacology and immunoconjugates with drugs and nanoparticles

The epidermal growth factor receptor (EGFR) belongs to the tyrosine kinase receptors family and is present in the epithelial cell membrane. Its endogenous activation occurs through the binding of different endogenous ligands, including the epidermal growth factor (EGF), leading to signaling cascades able to maintain normal cellular functions. Although involved in the development and maintenance of tissues in normal conditions, when EGFR is overexpressed, it stimulates the growth and progression of tumors, resulting in angiogenesis, invasion and metastasis, through some main cascades such as Ras/Raf/MAPK, PIK-3/AKT, PLC-PKC and STAT. Besides, considering the limitations of conventional chemotherapy that result in high toxicity and low tumor specificity, EGFR is currently considered an important target. As a result, several monoclonal antibodies are currently approved for use in cancer treatment, such as cetuximab (CTX), panitumumab, nimotuzumab, necitumumab and others are in clinical trials. Aiming to combine the chemotherapeutic agent toxicity and specific targeting to EGFR overexpressing tumor tissues, two main strategies will be discussed in this review: antibody-drug conjugates (ADCs) and antibody-nanoparticle conjugates (ANCs). Briefly, ADCs consist of antibodies covalently linked through a spacer to the cytotoxic drug. Upon administration, binding to EGFR and endocytosis, ADCs suffer chemical and enzymatic reactions leading to the release and accumulation of the drug. Instead, ANCs consist of nanotechnology-based formulations, such as lipid, polymeric and inorganic nanoparticles able to protect the drug against inactivation, allowing controlled release and also passive accumulation in tumor tissues by the enhanced permeability and retention effect (EPR). Furthermore, ANCs undergo active targeting through EGFR receptor-mediated endocytosis, leading to the formation of lysosomes and drug release into the cytosol. Herein, we will present and discuss some important aspects regarding EGFR structure, its role on internal signaling pathways and downregulation aspects. Then, considering that EGFR is a potential therapeutic target for cancer therapy, the monoclonal antibodies able to target this receptor will be presented and discussed. Finally, ADCs and ANCs state of the art will be reviewed and recent studies and clinical progresses will be highlighted. To the best of our knowledge, this is the first review paper to address specifically the EGFR target and its application on ADCs and ANCs.

In vivo drug delivery applications of nanogels: a review

In recent years, nanogels have emerged as promising drug delivery vehicles; their ability in holding active molecules, macromolecules and drugs, together with the capability to respond to external stimuli, makes them a suitable tool for a wide range of applications. These features allow nanogels to be exploited against many challenges of nanomedicine associated with different kinds of pathologies which require the use of specific drug delivery systems. In this review our aim is to give the reader an overview of the diseases that can be treated with nanogels as drug delivery systems, such as cancer, CNS disorders, cardiovascular diseases, wound healing and other diseases of human body. For all of these pathologies, biological in vivo assays can be found in the literature and in this work. We focus on the peculiarities of these nanogels, highlighting their features and their advantages in respect to conventional treatments.

ΕGFR/ERβ-Mediated Cell Morphology and Invasion Capacity Are Associated with Matrix Culture Substrates in Breast Cancer

Breast cancer accounts for almost one in four cancer diagnoses in women. Studies in breast cancer patients have identified several molecular markers, indicators of aggressiveness, which help toward more individual therapeutic approaches. In triple-negative breast cancer (TNBC), epidermal growth factor receptor (EGFR) overexpression is associated with increased metastatic potential and worst survival rates. Specifically, abnormal EGFR activation leads to altered matrix metalloproteinases' (MMPs) expression and, hence, extracellular matrix (ECM) degradation, resulting in induced migration and invasion. The use of matrix substrates for cell culture gives the opportunity to mimic the natural growth conditions of the cells and their microenvironment, as well as cell-cell and cell-matrix interactions. The aim of this study was to evaluate the impact of EGFR inhibition, estrogen receptor beta (ERβ) and different matrix substrates [type I collagen and fibronectin (FN)] on the functional properties, expression of MMPs and cell morphology of ERβ-positive TNBC cells and shERβ ones. Our results highlight EGFR as a crucial regulator of the expression and activity levels of MMPs, while ERβ emerges as a mediator of MMP7 and MT1-MMP expression. In addition, the EGFR/ERβ axis impacts the adhesion and invasion potential of breast cancer cells on collagen type I. Images obtained by scanning electron microscope (SEM) from cultures on the different matrix substrates revealed novel observations regarding various structures of breast cancer cells (filopodia, extravesicles, tunneling nanotubes, etc.). Moreover, the significant contribution of EGFR and ERβ in the morphological characteristics of these cells is also demonstrated, hence highlighting the possibility of dual pharmacological targeting.

Proteoglycans in the Pathogenesis of Hormone-Dependent Cancers: Mediators and Effectors

Hormone-dependent cancers exhibit high morbidity and mortality. In spite of advances in therapy, the treatment of hormone-dependent cancers remains an unmet health need. The tumor microenvironment (TME) exhibits unique characteristics that differ among various tumor types. It is composed of cancerous, non-cancerous, stromal, and immune cells that are surrounded and supported by components of the extracellular matrix (ECM). Therefore, the interactions among cancer cells, stromal cells, and components of the ECM determine cancer progression and response to therapy. Proteoglycans (PGs), hybrid molecules consisting of a protein core to which sulfated glycosaminoglycan chains are bound, are significant components of the ECM that are implicated in all phases of tumorigenesis. These molecules, secreted by both the stroma and cancer cells, are crucial signaling mediators that modulate the vital cellular pathways implicated in gene expression, phenotypic versatility, and response to therapy in specific tumor types. A plethora of deregulated signaling pathways contributes to the growth, dissemination, and angiogenesis of hormone-dependent cancers. Specific inputs from the endocrine and immune systems are some of the characteristics of hormone-dependent cancer pathogenesis. Importantly, the mechanisms involved in various aspects of cancer progression are executed in the ECM niche of the TME, and the PG components crucially mediate these processes. Here, we comprehensively discuss the mechanisms through which PGs affect the multifaceted aspects of hormone-dependent cancer development and progression, including cancer metastasis, angiogenesis, immunobiology, autophagy, and response to therapy.

Natural tyrosine kinase inhibitors acting on the epidermal growth factor receptor: Their relevance for cancer therapy

Epidermal growth factor receptor (EGFR), also known as ErbB-1/HER-1, plays a key role in the regulation of the cell proliferation, migration, differentiation, and survival. Since the constitutive activation or overexpression of EGFR is nearly found in various cancers, the applications focused on EGFR are the most widely used in the clinical level, including the therapeutic drugs of targeting EGFR, monoclonal antibodies (mAbs) and tyrosine kinase inhibitors (TKIs).Over the past decades, the compounds from natural sources have been a productive source of novel drugs, especially in both discovery and development of anti-tumor drugs by targeting the EGFR pathways as the TKIs. This work presents a review of the compounds from natural sources as potential EGFR-TKIs involved in the regulation of cancer. Moreover, high-throughput drug screening of EGFR-TKIs from the natural compounds has also been summarized.

Oncogenic Potential of Bisphenol A and Common Environmental Contaminants in Human Mammary Epithelial Cells

There is an ample epidemiological evidence to support the role of environmental contaminants such as bisphenol A (BPA) in breast cancer development but the molecular mechanisms of their action are still not fully understood. Therefore, we sought to analyze the effects of three common contaminants (BPA; 4-tert-octylphenol, OP; hexabromocyclododecane, HBCD) on mammary epithelial cell (HME1) and MCF7 breast cancer cell line. We also supplied some data on methoxychlor, MXC; 4-nonylphenol, NP; and 2-amino-1-methyl-6-phenylimidazo [4–b] pyridine, PhIP. We focused on testing the prolonged (two months) exposure to low nano-molar concentrations (0.0015–0.0048 nM) presumed to be oncogenic and found that they induced DNA damage (evidenced by upregulation of pH2A.X, pCHK1, pCHK2, p-P53) and disrupted the cell cycle. Some agents induced epigenetic (methylation) changes of tumor suppressor genes TIMP3, CHFR, ESR1, IGSF4, CDH13, and GSTP1. Obviously, the accumulation of these molecular alterations is an essential base for cancer development. Consistent with this, we observed that these agents increased cellular invasiveness through collagen. Cellular abilities to form colonies in soft agar were increased for MCF7. Toxic agents induced phosphorylation of protein kinase such as EGFR, CREB, STAT6, c-Jun, STAT3, HSP6, HSP27, AMPKα1, FAK, p53, GSK-3α/β, and P70S6 in HME1. Most of these proteins are involved in potential oncogenic pathways. Overall, these data clarify the molecular alterations that can be induced by some common environmental contaminants in mammary epithelial cells which could be a foundation to understand environmental carcinogenesis.

1‑Palmitoyl‑2‑linoleoyl‑3‑acetyl‑rac‑glycerol ameliorates EGF‑induced MMP‑9 expression by promoting receptor desensitization in MDA‑MB‑231 cells

Activated epidermal growth factor receptors (EGFRs) are crucial for inducing metastasis in cancer cells by promoting matrix metalloproteinase (MMP) expression. The present study was designed to investigate the effects of 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) on MMP expression in epidermal growth factor (EGF)-stimulated breast cancer cells in vitro. EGF stimulation induced internalization of its cognate receptor, EGFR, for stimulus-desensitization. These internalized receptors, complexed with the ubiquitin ligase c-Cbl and EGFR pathway substrate 15 (EPS15) (for degradation), were evaluated by confocal microscopy at 5–90 min time intervals. During intracellular trafficking of EGFRs, EGF-induced signaling cascades were analyzed by examining EGFR and SHC phosphorylation. Modulation of MMP expression was assessed by evaluating the activity of transcription factor AP-1 using a luciferase assay. PLAG accelerated the assembly of EGFRs with c-Cbl and EPS15 and promoted receptor degradation. This faster intracellular EGFR degradation reduced AP-1-mediated MMP expression. PLAG stimulation upregulated thioredoxin-interacting protein (TXNIP) expression, and this mediated the accelerated receptor internalization. This PLAG-induced increase in EGFR trafficking was blocked in TXNIP-silenced cells. By downregulating MMP expression, PLAG effectively attenuated EGF-induced mobility and invasiveness in these cancer cells. These data suggest that PLAG may be a potential therapeutic agent for blocking metastasis.

Long filopodia and tunneling nanotubes define new phenotypes of breast cancer cells in 3D cultures

Cancer cell invasion into the surrounding extracellular matrix (ECM) takes place when cell-cell junctions are disrupted upon epithelial-to-mesenchymal transition (EMT). Both cancer cell-stroma and cell-cell crosstalk are essential to support the continuous tumor invasion. Cancer cells release microvesicles and exosomes containing bioactive molecules and signal peptides, which are recruited by neighboring cells or carried to distant sites, thus supporting intercellular communication and cargo transfer. Besides this indirect communication mode, cancer cells can develop cytoplasmic intercellular protrusions or tunneling nanotubes (TNTs), which allow the direct communication and molecular exchange between connected distinct cells. Using scanning electron microscopy (SEM) we show for the first time that MDA-MB-231 (high metastatic potential) and shERβ MDA-MB-231 (low metastatic potential) breast cancer cells cultured on fibronectin and collagen type I or 17β-estradiol (E2) develop TNTs and very long flexible filopodia. Interestingly, the less aggressive shERβ MDA-MB-231 cells treated with E2 in 3D collagen matrix showed the highest development of TNTs and filopodia. TNTs were often associated to adhering exosomes and microvesicles surfing from one cell to another, but no filopodia exhibited vesicle-like cytoplasmic structures on their surface. Moreover, E2 affected the expression of matrix macromolecules and cell effectors mostly in the presence of ERβ. Our novel data highlights the significance of matrix substrates and the presence of E2 and ERβ in the formation of cellular protrusion and the production of surface structures, defining novel phenotypes that unravel nodal reports for breast cancer progression.

Coating and Functionalization Strategies for Nanogels and Nanoparticles for Selective Drug Delivery

Drug delivery is a fascinating research field with several development opportunities. Great attention is now focused on colloidal systems, nanoparticles, and nanogels and on the possibility of modifying them in order to obtain precise targeted drug delivery systems. The aim of this review is to give an overview of the main available surface functionalization and coating strategies that can be adopted in order to modify the selectivity of the nanoparticles in the delivery process and obtain a final system with great targeted drug delivery ability. We also highlight the most important fields of application of these kinds of delivery systems and we propose a comparison between the advantages and disadvantages of the described functionalization strategies.

EGF receptor stimulation shifts breast cancer cell glucose metabolism toward glycolytic flux through PI3 kinase signaling

Breast cancers that express epidermal growth factor (EGF) receptors (EGFRs) are associated with poor prognosis. Our group recently showed in breast cancer patients that EGFR expression is strongly correlated with high tumor uptake of the glucose analogue, ¹⁸F-fluorodeoxyglucose (FDG). Here, we explored the cellular mechanism and signaling pathways that can explain the relation between EGFR and breast cancer cell glucose metabolism. FDG uptake, lactate production and hexokinase (HK) activity were measured, and proliferation assays and western blots were performed. EGF stimulated an increase of FDG uptake in EGFR-positive T47D and MDA-MB-468 cells, but not in MCF-7 cells. In T47D cells, the effect was dose-dependent and was accompanied by increased lactate production, indicating a shift toward glycolytic flux. This metabolic response occurred through enhanced HK activity and upregulated glucose transporter 1 (GLUT1) expression. EGFR stimulation also increased T47D cell proliferation. Blocking EGFR activation with BIBX1382 or gefitinib completely abolished both FDG uptake and proliferation effects. EGFR stimulation induced MAP kinase (MAPK) and PI3 kinase (PI3K) activation. Increased cell proliferation by EGFR stimulation was completely abolished by MAPK inhibition with PD98059 or by PI3K inhibition with LY294002. Increased FDG uptake was also completely abrogated by PI3K inhibition but was uninfluenced by MAPK inhibition. These findings suggest that the association between breast tumor EGFR expression and high FDG uptake might be contributed by stimulation of the PI3K pathway downstream of EGFR activation. This was in contrast to EGFR-mediated cell proliferation that required MAPK as well as PI3K signaling.

MicroRNA-6077 enhances the sensitivity of patients-derived lung adenocarcinoma cells to anlotinib by repressing the activation of glucose transporter 1 pathway

Anlotinib is a novel molecular targeted agent targeting the vascular endothelial growth factor receptor, which differs from the other currently available non-small cell lung cancer (NSCLC) molecular targeted drugs targeting this receptor. Although the application of anlotinib may bring new hope for patients with advanced NSCLC, the cost of treatment is high. The results of this study showed that microRNA-6077 (miR-6077) represses the expression of GLUT1 (glucose transporter 1) and enhances the sensitivity of patient-derived lung adenocarcinoma (AC) cells to anlotinib. The miR-6077, which potentially binds to the 3'untranslated region of GLUT1, was identified and screened by miRDB, an online tool; sequences of miR-6077 were prepared as lentivirus particles. A549 cells (a lung adenocarcinoma cell line) and five patient-derived AC cell lines were infected with control miRNA or miR-6077, and subsequently treated with the indicated concentration of anlotinib. The expression of proteins, such as GLUT1, was determined by western blotting. The antitumor effect of anlotinib was identified through in-vitro (e.g., MTT) or in-vivo methods (e.g., subcutaneous tumor model). Overexpression of miR-6077 repressed the expression of GLUT1 and decreased the glucose uptake, lactate production, or ATP generation in AC cells. In addition, MiR-6077 may enhance the antitumor effect of anlotinib on A549 or patient-derived AC cell lines. Therefore, our results indicated that miR-6077 represses the expression of GLUT1 and enhances the sensitivity of patients-derived lung AC cells to anlotinib.

MicroRNA-3662 targets ZEB1 and attenuates the invasion of the highly aggressive melanoma cell line A375

Background

Cutaneous melanoma is the most aggressive form of skin cancer. It accounts for approximately 5% of all cutaneous malignancies and is currently responsible for the majority of skin cancer-related deaths. However, the exact mechanisms responsible for the occurrence of melanoma, in particular the invasive growth in normal skin or muscle tissue, remain unknown.

Materials and methods

miR-3662, a microRNA is a potential tumor suppressor targeting zinc finger E-box binding homeobox 1 (ZEB1), which functions as a key regulator of the epithelial-mesenchymal transition (EMT) process. This microRNA was identified using an online database (miRDB) and expression was confirmed by Western blot analysis. Quantitative polymerase chain reaction (qPCR) was used to examine whether miR-3662 inhibits the EMT process in the aggressive melanoma cell line, A375, through the modification of the expression of invasion-related genes in A375 cells. The effects of miR-3662 on the in vivo growth of A375 cells were examined in a nude mouse model.

Results

Using virtual screening of the miRDB database, miR-3662 was shown to target the 3ʹ untranslated region (UTR) of the ZEB1 gene. Expression of miR-3662 via a lentivirus vector significantly decreased protein levels of ZEB1 and inhibited the growth of A375 cells in vitro and in vivo. The reduction in ZEB1 expression induced by miR-3662 resulted in EMT inhibition in A375 cells and decreased the relative expression of metastasis genes.

Conclusion

Down-regulation of ZEB1’s expression via miR-3662 lentivirus vectors significantly decreased the in vitro and in vivo growth of the highly aggressive melanoma cell line A375.

N-Glycosylation in progression of skin cancer

Skin cancer can be classified as cutaneous malignant melanoma, basal cell carcinoma, and squamous cell carcinoma. Due to the high level of morbidity and mortality, skin cancer has become a global public health issue worldwide while the pathogenesis of skin cancer is still unclear. It is necessary to further identify the pathogenesis of skin cancer and find candidate targets to diagnose and treat skin cancer. A variety of factors are known to be associated with skin cancer including N-glycosylation, which partly explained the malignant behaviors of skin cancer. In this review, we retrieved databases such as PubMed and Web of Science to elucidate its relationship between glycosylation and skin cancer. We summarized some key glycosyltransferases and proteins during the process of N-glycosylation related to skin cancer, which was helpful to unmask the additional mechanism of skin cancer and find some novel targets of skin cancer.

Mechanism of Rapid Nuclear Factor-E2-Related Factor 2 (Nrf2) Activation via Membrane-Associated Estrogen Receptors: Roles of NADPH Oxidase 1, Neutral Sphingomyelinase 2 and Epidermal Growth Factor Receptor (EGFR)

Membrane-associated estrogen receptors (ER)-α36 and G protein-coupled estrogen receptor (GPER) play important roles in the estrogen’s rapid non-genomic actions including stimulation of cell proliferation. Estrogen via these receptors induces rapid activation of transcription factor nuclear factor-E2-related factor 2 (Nrf2), a master regulator of detoxification and antioxidant systems, playing a key role in the metabolic reprogramming to support cell proliferation. This review highlights the possible mechanism underlying rapid Nrf2 activation via membrane-associated estrogen receptors by estrogen and phytoestrogens. Stimulation of ER-α36-GPER signaling complex rapidly induces Src-mediated transactivation of epidermal growth factor receptor (EGFR) leading to a kinase-mediated signaling cascade. We propose a novel hypothesis that ER-α36-GPER signaling initially induces rapid and temporal activation of NADPH oxidase 1 to generate superoxide, which subsequently activates redox-sensitive neutral sphingomyelinase 2 generating the lipid signaling mediator ceramide. Generation of ceramide is required for Ras activation and ceramide-protein kinase C ζ-casein kinase 2 (CK2) signaling. Notably, CK2 enhances chaperone activity of the Cdc37-Hsp90 complex supporting activation of various signaling kinases including Src, Raf and Akt (protein kinase B). Activation of Nrf2 may be induced by cooperation of two signaling pathways, (i) Nrf2 stabilization by direct phosphorylation by CK2 and (ii) EGFR-Ras-PI 3 kinase (PI3K)-Akt axis which inhibits glycogen synthase kinase 3β leading to enhanced nuclear transport and stability of Nrf2.

The LXR-623-induced long non-coding RNA LINC01125 suppresses the proliferation of breast cancer cells via PTEN/AKT/p53 signaling pathway

LXR-623 (WAY-252623), a liver X receptor agonist, reduces atherosclerotic plaque progression and remarkably inhibits the proliferation of glioblastoma cells, owing to its brain-penetrant ability. However, the role of LXR-623 against the proliferation of other cancer cells and the underlying mechanism remain unknown. Long non-coding RNAs (lncRNAs) serve as novel and crucial regulators that participate in cancer tumorigenesis and diverse biological processes. Here, we report a previously uncharacterized mechanism underlying lncRNA-mediated exocytosis of LXR-623 via the phosphatase and tensin homolog (PTEN)/protein kinase B (AKT)/p53 axis to suppress the proliferation of cancer cells in vitro. We found that LXR-623 significantly inhibited the proliferation and induced apoptosis and cell cycle arrest at S phase in breast cancer cells in a concentration- and time-dependent manner. Experiments using a xenograft mouse model revealed the inhibitory effects of LXR-623 on tumor growth. We used lncRNA microarray to investigate the potential genes regulated by LXR-623. As a result, LINC01125 was found to be significantly upregulated in the cells treated with LXR-623. Gain- and loss-of-function assays were conducted to investigate the anti-proliferation role of LINC01125. LINC01125 knockdown resulted in the inhibition of the cytotoxic effect of LXR-623; in contrast, LINC01125 overexpression significantly enhanced the effect of LXR-623. LXR-623 and LINC01125-mediated anti-growth regulation is, at least in part, associated with the participation of the PTEN/AKT/mouse double minute 2 homolog (MDM2)/p53 pathway. In addition, SF1670, a specific PTEN inhibitor with prolonged intracellular retention, may strongly block the anti-proliferation effect induced by LXR-623 and LINC01125 overexpression. Chromatin immunoprecipitation (ChIP) assay results suggest that p53 binds to the promoter of LINC01125 to strengthen the expression of the PTEN/AKT pathway. Taken together, our findings suggest that LXR-623 possesses significant antitumor activity in breast cancer cells that is partly mediated through the upregulation in LINC01125 expression and enhancement in apoptosis via the PTEN/AKT/MDM2/p53 pathway.

Hyaluronan: molecular size-dependent signaling and biological functions in inflammation and cancer

Hyaluronan (HA) is a linear nonsulfated glycosaminoglycan of the extracellular matrix that plays a pivotal role in a variety of biological processes. High-molecular weight HA exhibits different biological properties than oligomers and low-molecular weight HA. Depending on their molecular size, HA fragments can influence cellular behavior in a different mode of action. This phenomenon is attributed to the different manner of interaction with the HA receptors, especially CD44 and RHAMM. Both receptors can trigger signaling cascades that regulate cell functional properties, such as proliferation migration, angiogenesis, and wound healing. HA fragments are able to enhance or attenuate the HA receptor-mediated signaling pathways, as they compete with the endogenous HA for binding to the receptors. The modulation of these pathways could be crucial for the development of pathological conditions, such as inflammation and cancer. The primary goal of this review is to critically present the importance of HA molecular size on cellular signaling, functional cell properties, and morphology in normal and pathological conditions, including inflammation and cancer. A deeper understanding of these mechanisms could contribute to the development of novel therapeutic strategies.

Understanding the evolutionary trend of intrinsically structural disorders in cancer relevant proteins as probed by Shannon entropy scoring and structure network analysis

BACKGROUND

Malignant diseases have become a threat for health care system. A panoply of biological processes is involved as the cause of these diseases. In order to unveil the mechanistic details of these diseased states, we analyzed protein families relevant to these diseases.

RESULTS

Our present study pivots around four apparently unrelated cancer types among which two are commonly occurring viz. Prostate Cancer, Breast Cancer and two relatively less frequent viz. Acute Lymphoblastic Leukemia and Lymphoma. Eight protein families were found to have implications for these cancer types. Our results strikingly reveal that some of the proteins with implications in the cancerous cellular states were showing the structural organization disparate from the signature of the family it constitutes. The sequences were further mapped onto respective structures and compared with the entropic profile. The structures reveal that entropic scores were able to reveal the inherent structural bias of these proteins with quantitative precision, otherwise unseen from other analysis. Subsequently, the betweenness centrality scoring of each residue from the structure network models was resorted to explore the changes in dependencies on residue owing to structural disorder.

CONCLUSION

These observations help to obtain the mechanistic changes resulting from the structural orchestration of protein structures. Finally, the hydropathy indexes were obtained to validate the sequence space observations using Shannon entropy and in-turn establishing the compatibility.