Nectin family of cell-adhesion molecules: structural and molecular aspects of function and specificity

Nectin-4-directed antibody-drug conjugates (ADCs): Spotlight on preclinical and clinical evidence

Nectin-4 (Nectin cell adhesion molecule 4), a type I transmembrane cell adhesion protein, was demonstrated to be overexpressed in a variety of tumors, making it an attractive antigen for targeted therapies such as antibody-drug conjugates (ADCs). Of great note, the US Food and Drug Administration (FDA)-approval of the first Nectin-4-directed ADC, enfortumab vedotin (EV), in urothelial cancer (UC) not only introduced Nectin-4 as a clinically validated and reliable target antigen but also confirmed the evolving role of Nectin-4-directed ADCs as novel and promising cancer therapeutics. In addition to EV, there have been or are currently being seven and eleven Nectin-4-directed ADCs, respectively, in various stages of clinical trials and preclinical development, offering a promising future for the treatment of Nectin-4-positive cancer patients. This study reviewed clinical- and preclinical-stage Nectin-4-directed ADCs.

Biomaterials with cancer cell-specific cytotoxicity: challenges and perspectives

Significant advances have been made in materials for biomedical applications, including tissue engineering, bioimaging, cancer treatment, etc. In the past few decades, nanostructure-mediated therapeutic strategies have been developed to improve drug delivery, targeted therapy, and diagnosis, maximizing therapeutic effectiveness while reducing systemic toxicity and side effects by exploiting the complicated interactions between the materials and the cell and tissue microenvironments. This review briefly introduces the differences between the cells and tissues of tumour or normal cells. We summarize recent advances in tumour microenvironment-mediated therapeutic strategies using nanostructured materials. We then comprehensively discuss strategies for fabricating nanostructures with cancer cell-specific cytotoxicity by precisely controlling their composition, particle size, shape, structure, surface functionalization, and external energy stimulation. Finally, we present perspectives on the challenges and future opportunities of nanotechnology-based toxicity strategies in tumour therapy.

A new era for bladder cancer: Enfortumab vedotin and pembrolizumab milestone approval

Cisplatin-based combos have become first-line treatment regimens in standard of care because of their high overall survival improvement. Despite being the first-line therapy, due to its side effects, roughly half of all patients suffering from Metastatic urothelial cancer are ineligible for it. To address this issue, scientists have been developing highly specific antibody-drug conjugates to address this issue. For locally advanced or metastatic bladder cancer, a combination of Padcev (enfortumab vedotin-ejfv) with pembrolizumab (Keytruda) has been authorized by the FDA as a first-line treatment and has shown promising outcomes in patients with metastatic urothelial carcinoma who are ineligible for cisplatin-based combinations.

Antibody-drug conjugates in cancer therapy: mechanisms and clinical studies

Antibody-drug conjugates (ADCs) consist of monoclonal antibodies that target tumor cells and cytotoxic drugs linked through linkers. By leveraging antibodies' targeting properties, ADCs deliver cytotoxic drugs into tumor cells via endocytosis after identifying the tumor antigen. This precise method aims to kill tumor cells selectively while minimizing harm to normal cells, offering safe and effective therapeutic benefits. Recent years have seen significant progress in antitumor treatment with ADC development, providing patients with new and potent treatment options. With over 300 ADCs explored for various tumor indications and some already approved for clinical use, challenges such as resistance due to factors like antigen expression, ADC processing, and payload have emerged. This review aims to outline the history of ADC development, their structure, mechanism of action, recent composition advancements, target selection, completed and ongoing clinical trials, resistance mechanisms, and intervention strategies. Additionally, it will delve into the potential of ADCs with novel markers, linkers, payloads, and innovative action mechanisms to enhance cancer treatment options. The evolution of ADCs has also led to the emergence of combination therapy as a new therapeutic approach to improve drug efficacy.

Opportunities and Challenges in the Development of Antibody-Drug Conjugate for Triple-Negative Breast Cancer: The Diverse Choices and Changing Needs

Triple-negative breast cancer (TNBC) is a highly heterogeneous breast cancer subtype, which is also characterized by the aggressive phenotype, high recurrence rate, and poor prognosis. Antibody-drug conjugate (ADC) is a monoclonal antibody with a cytotoxic payload connected by a linker. ADC is gaining more and more attention as a targeted anti-cancer agent. Clinical studies of emerging ADC drugs such as sacituzumab govitecan and trastuzumab deruxtecan in patients with metastatic breast cancer (including TNBC) are progressing rapidly. In view of its excellent clinical efficacy and good tolerability, Sacituzumab govitecan gained accelerated approval by the FDA for the treatment of advanced metastatic TNBC in 2020. This review discusses the treatment status and challenges in TNBC, with an emphasis on the current status of ADC development and clinical trials in TNBC and metastatic breast cancer. We also summarize the clinical experience and future exploration directions of ADC development for TNBC patients.

Molecular Crosstalk Between Adherens Junction Proteins, E-cadherin and Nectin-4

Cell-cell junctions formed by the association of cell adhesion molecules facilitate physiological events necessary for growth and development of multicellular organisms. Among them, cadherins and nectins organize and assemble to form adherens junction, which thereby mechanically couples interacting cells. A detailed understanding of the crosstalk involving these cell adhesion molecules is fundamental to the study of the various developmental processes. Although, cadherins and nectins can recruit each other in the adherens junction through an interplay of cytoplasmic adaptor molecules, here, we report a direct interaction between N-terminal extracellular domains of E-cadherin and nectin-4 as demonstrated by surface plasmon resonance (SPR) and Atomic Force Microscopy (AFM)-based single molecule force spectroscopy (SMFS). Kinetic studies using SPR demonstrate the binding between the ectodomains of E-cadherin and nectin-4 with a KD of 3.7 ± 0.7 µM and KD of 5.4 ± 0.2 µM (reciprocal experiment). AFM-based SMFS experiments also support interaction between the ectodomains of E-cadherin and nectin-4 with the koff value of 31.48 ± 1.53 s-1 and the lifetime of the complex of 0.036 ± 0.0026 s. We thus propose a cell adhesion mechanism mediated by E-cadherin and nectin-4, which can have functional significance in early embryogenesis as evident from the expression pattern of both the proteins during early development.

Anti-HSV activity of nectin-1-derived peptides targeting HSV gD: an in-silico and in-vitro approach

Herpes simplex virus (HSV) infections affect a wide range of the global population. The emergence of resistance to the existing anti-HSV therapy highlights the necessity for an innovative strategy. The interaction of HSV gD with its main host receptor nectin-1 is a potential target for new antiviral drugs. The aim of this study was to develop a peptide derived from nectin-1 targeting HSV gD using the in-silico method and evaluate them for anti-HSV activity. Residues 59-133 of the Nectin-1 V-domain constitute the interaction interface with HSV gD. Bioinformatic tools viz., PEP-FOLD3, ClusPro 2.0, HawkDock and Desmond were used to model the peptide and confirm its binding specificity with HSV gD protein. The peptides with potential interactions were custom synthesized and anti-HSV activity was evaluated in vitro against HSV-1 and HSV-2 by CPE inhibition assay. Five peptide sequences were identified as exhibiting good interaction with HSV-gD proteins. Among them, peptide N1 (residues 76-90) offered maximum protection against HSV-1 (66.57%) and HSV-2 (71.12%) infections. Modification of the identified peptide through peptidomimetic approaches may further enhance the activity and stability of the identified peptide.Communicated by Ramaswamy H. Sarma.

CD56/NCAM mediates cell migration of human NK cells by promoting integrin-mediated adhesion turnover

Natural killer (NK) cells patrol tissue to mediate lysis of virally infected and tumorigenic cells. Human NK cells are typically identified by their expression of neural cell adhesion molecule (NCAM, CD56), yet despite its ubiquitous expression on NK cells, CD56 remains a poorly understood protein on immune cells. CD56 has been previously demonstrated to play roles in NK cell cytotoxic function and cell migration. Specifically, CD56-deficient NK cells have impaired cell migration on stromal cells and CD56 is localized to the uropod of NK cells migrating on stroma. Here, we show that CD56 is required for NK cell migration on ICAM-1 and is required for the establishment of persistent cell polarity and unidirectional actin flow. The intracellular domain of CD56 (NCAM-140) is required for its function and the loss of CD56 leads to enlarged actin foci and sequestration of phosphorylated Pyk2 accompanied by increased size and frequency of activated LFA-1 clusters. Together, these data identify a role for CD56 in regulating human NK cell migration through modulation of actin dynamics and integrin turnover.

Downregulation of endogenous nectin1 in human keratinocytes by herpes simplex virus 1 glycoprotein D excludes superinfection but does not affect NK cell function

Many viruses downregulate their cognate receptors, facilitating virus replication and pathogenesis via processes that are not yet fully understood. In the case of herpes simplex virus 1 (HSV1), the receptor binding protein glycoprotein D (gD) has been implicated in downregulation of its receptor nectin1, but current understanding of the process is limited. Some studies suggest that gD on the incoming virion is sufficient to achieve nectin1 downregulation, but the virus-encoded E3 ubiquitin ligase ICP0 has also been implicated. Here we have used the physiologically relevant nTERT human keratinocyte cell type - which we have previously shown to express readily detectable levels of endogenous nectin1 - to conduct a detailed investigation of nectin1 expression during HSV1 infection. In these cells, nectin1, but not nectin2 or the transferrin receptor, disappeared from the cell surface in a process that required virus protein synthesis rather than incoming virus, but did not involve virus-induced host shutoff. Furthermore, gD was not only required but was sufficient for nectin1 depletion, indicating that no other virus proteins are essential. NK cells were shown to be activated in the presence of keratinocytes, a process that was greatly inhibited in cells infected with wild-type virus. However, degranulation of NK cells was also inhibited in ΔgD-infected cells, indicating that blocking of NK cell activation was independent of gD downregulation of nectin1. By contrast, a superinfection time-course revealed that the ability of HSV1 infection to block subsequent infection of a GFP-expressing HSV1 was dependent on gD and occurred in line with the timing of nectin1 downregulation. Thus, the role of gD-dependent nectin1 impairment during HSV infection is important for virus infection, but not immune evasion, which is achieved by other mechanisms.

NECTIN4-targeted antibody-drug conjugate is a potential therapeutic option for extramammary Paget disease

Extramammary Paget disease (EMPD) is a rare skin cancer mainly found in areas rich in apocrine sweat glands. Since the effective treatments for advanced and/or metastasized EMPD are limited, there is an urgent need to develop novel therapeutic approaches. Nectin cell adhesion molecule 4 (NECTIN4) is highly expressed in cancers and considered to be a promising therapeutic target. NECTIN4 is also expressed in EMPD, but its role and the efficacy of NECTIN4-targeted therapy in EMPD remain unclear. This study investigated the potential of NECTIN4 as a novel therapeutic target for EMPD. NECTIN4 expression was immunohistochemically analysed in EMPD patients' primary (118 samples) and metastatic (21 samples) lesions. Using an EMPD cell line, KS-EMPD-1, the effects of NECTIN4 inhibition on cell proliferation and migration were investigated. NECTIN4 was expressed in primary and metastatic EMPD lesions, and the H-score of NECTIN4 staining was significantly higher in metastatic lesions than in primary ones. Knockdown of NECTIN4 significantly inhibited cell proliferation and affected cell migration. The cytotoxic effects of NECTIN4-targeted antibody-drug conjugate (ADC) were further evaluated, revealing a significant decrease in EMPD cell viability. In conclusion, NECTIN4 is a potential therapeutic target and NECTIN4-targeted ADC is promising as a therapeutic option for EMPD.

Interferon-stimulated gene PVRL4 broadly suppresses viral entry by inhibiting viral-cellular membrane fusion

BACKGROUND

Viral infection elicits the type I interferon (IFN-I) response in host cells and subsequently inhibits viral infection through inducing hundreds of IFN-stimulated genes (ISGs) that counteract many steps in the virus life cycle. However, most of ISGs have unclear functions and mechanisms in viral infection. Thus, more work is required to elucidate the role and mechanisms of individual ISGs against different types of viruses.

RESULTS

Herein, we demonstrate that poliovirus receptor-like protein4 (PVRL4) is an ISG strongly induced by IFN-I stimulation and various viral infections. Overexpression of PVRL4 protein broadly restricts growth of enveloped RNA and DNA viruses, including vesicular stomatitis virus (VSV), herpes simplex virus 1 (HSV-1), influenza A virus (IAV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) whereas deletion of PVRL4 in host cells increases viral infections. Mechanistically, it suppresses viral entry by blocking viral-cellular membrane fusion through inhibiting endosomal acidification. The vivo studies demonstrate that Pvrl4-deficient mice were more susceptible to the infection of VSV and IAV.

CONCLUSION

Overall, our studies not only identify PVRL4 as an intrinsic broad-spectrum antiviral ISG, but also provide a candidate host-directed target for antiviral therapy against various viruses including SARS-CoV-2 and its variants in the future.

An iodine‑labelled Antibody-drug conjugate PET probe for noninvasive monitoring of Nectin-4 expression in urothelial carcinoma

BACKGROUND AND PURPOSE

Some kinds of antibody-drug conjugate (ADC) with high affinity to Nectin-4 have demonstrated breakthrough progress in the third-line setting for bladder cancer. However, many patients are still difficult to benefit from treatment based on the heterogeneity of tumour. As the most advanced auxiliary treatment technology, treatment visualization can most intuitively predict the effectiveness of drug treatment, and timely detect the occurrence of drug resistance. Among them, nuclear medicine molecular probes play an important role in this field.

METHODS

124/125I-EV was prepared by labelling Enfortumad Vedetin (EV), an ADC drugs widely used in clinic targeted Nectin-4, with Na124/125I using N-bromine succinimide as oxidant. The radiochemical purity was analyzed via radio-TLC and bioactivity was measured by enzyme-linked immunosorbent assay. Cell uptake assay and small-animal PET imaging were performed to verified the specificity and targeting.

KEY RESULTS

124/125I-EV was prepared with high labeling yield and radiochemical purity. ELISA assays demonstrated that 124I-EV maintained the same high bioactivity as EV with significantly higher uptake in SW780 cells (Nectin-4 positive, 4.05 ± 0.32 %IA/5 × 105 cells at 8 h) than that in T24 cells (Nectin-4 negative, 1.34 ± 0.18 %IA/5 × 105 cells, p < 0.001). In PET imaging, 124I-EV had a significantly higher accumulation in SW780 tumour than that in T24 tumour and the uptake in SW780 tumour could be specifically blocked when co-injected with cold EV. The signal-to-noise ratio at the tumour site gradually increased with time, and peaked at 72 h.

CONCLUSION AND IMPLICATIONS

124I-EV was successfully prepared with high specificity and binding affinity of Nectin-4. This radioactive probe completely simulates the internal circulation of ADC drugs and tumour uptake and retention, which will greatly improve the clinical application of ADC therapy.

Structural basis of molecular recognition among classical cadherins mediating cell adhesion

Cadherins are type-I membrane glycoproteins that primarily participate in calcium-dependent cell adhesion and homotypic cell sorting in various stages of embryonic development. Besides their crucial role in cellular and physiological processes, increasing studies highlight their involvement in pathophysiological functions ranging from cancer progression and metastasis to being entry receptors for pathogens. Cadherins mediate these cellular processes through homophilic, as well as heterophilic interactions (within and outside the superfamily) by their membrane distal ectodomains. This review provides an in-depth structural perspective of molecular recognition among type-I and type-II classical cadherins. Furthermore, this review offers structural insights into different dimeric assemblies like the 'strand-swap dimer' and 'X-dimer' as well as mechanisms relating these dimer forms like 'two-step adhesion' and 'encounter complex'. Alongside providing structural details, this review connects structural studies to bond mechanics merging crystallographic and single-molecule force spectroscopic findings. Finally, the review discusses the recent discoveries on dimeric intermediates that uncover prospects of further research beyond two-step adhesion.

Nectin-4 has emerged as a compelling target for breast cancer

The incidence of breast cancer in women has increased year by year, becoming one of the most common malignant tumors in females worldwide. Most patients can be treated with surgery and endocrine drugs, but there are still some patients who lack effective treatment, such as triple-negative breast cancer (TNBC). Nectin-4, a protein encoded by poliovirus receptor-associated protein 4, is a Ca2+-independent immunoglobulin-like protein. It is mainly involved in the adhesion between cells. In recent years, studies have found that Nectin-4 is overexpressed in breast cancer and several other malignancies. Otherwise, several monoclonal antibodies and inhibitors targeting Nectin-4 have shown prosperous outcomes, so Nectin-4 has great potential to be a therapeutic target for breast cancer. The present review systematically describes the significance of Nectin-4 in each aspect of breast cancer, as well as the molecular mechanisms of these aspects mediated by Nectin-4. We further highlight ongoing or proposed therapeutic strategies for breast cancer specific to Nectin-4.

Diabetic Ketoacidosis and Acute Kidney Injury Associated With Enfortumab Vedotin for Urothelial Carcinoma: A Case Report

Enfortumab vedotin is a novel breakthrough therapy that received accelerated US Food and Drug Administration approval in 2019 for the treatment of metastatic urothelial carcinoma in patients who have failed other lines of treatment. The characteristics of its adverse effects are not well understood. Diabetic ketoacidosis has been reported in 2 postmarketing reports presented as abstracts at the 2020 American Thoracic Society Conference and the 2021 American Society of Nephrology Conference. Both cases progressed rapidly and expired in <3 days. We present a similar case of a man in his late 50s with no history of diabetes who was diagnosed with urothelial carcinoma 2 years prior. Despite several lines of treatment, including platinum-based chemotherapy and immune checkpoint inhibitors, he developed metastasis and was started on enfortumab vedotin. After his second dose of enfortumab vedotin, he was admitted to the intensive care unit for diabetic ketoacidosis with an initial A1C level of 7.7%. He was intubated for airway protection, started on pressors, and developed oliguric acute kidney injury requiring continuous venovenous hemodialysis. Despite aggressive treatment, the patient died on hospital day 2. The lethality of this aggressive diabetic ketoacidosis despite therapy suggests some other effect of enfortumab vedotin on glucose metabolism in addition to insulin resistance and the need for prior diabetes screening.

Impact of sampling location and aging on the Longissimus thoracis et lumborum muscle proteome of dry-aged beef

This study aimed to explore the differences in the proteome and molecular pathways between two sampling locations (external, internal) of bovine Longissimus thoracis et lumborum (LTL) muscles at 0, 21, and 28 days of dry-aging (i.e. 3, 24, and 31 days post-mortem). It further assessed the impact of post-mortem aging on the meat proteome changes and the biological processes at interplay. Proteins related to defence response to bacterium and regulation of viral entry into host cell were identified to be more abundant on the external location before dry-aging, which may be associated to the oxidative conditions and microbial activity to which post-mortem muscle is exposed during dressing, chilling, and/or quartering of the carcasses. This highlights the relevance of sampling from interior tissues when searching for meat quality biomarkers. As dry-aging progressed, the meat proteome and related biological processes changed differently between sampling locations; proteins related to cell-cell adhesion and ATP metabolic processes pathways were revealed in the external location at 21 and 28 days, respectively. On the other hand, the impact of aging on the proteome of the interior meat samples, evidenced that muscle contraction and structure together with energy metabolism were the major pathways driving dry-aging. Additionally, aging impacted other pathways in the interior tissues, such as regulation of calcium import, neutrophil activation, and regeneration. Overall, the differences in the proteome allowed discriminating the three dry-aging times, regardless of the sampling location. Several proteins were proposed for validation as robust biomarkers to monitor the aging process (tenderization) of dry-aged beef: TTN, GRM4, EEF1A1, LDB3, CILP2, TNNT3, GAPDH, SERPINI1, and OMD.

Molecular and structural basis of TIGIT: Nectin-4 interaction, a recently discovered pathway crucial for cancer immunotherapy

TIGIT (T cell immunoglobulin and ITIM domain) is an inhibitory receptor expressed on T and NK cells that interact with cell surface glycoprotein belonging to the nectin and nectin-like family of cell adhesion molecules, particularly nectin-2 and nectin-like 5 (PVR). Nectin-4 has been recently identified as a novel ligand for TIGIT and the interaction among them inhibits NK cell cytotoxicity. In this study, biophysical experiments were conducted to decipher the mechanism of this novel interaction, followed by structure-guided mutagenesis studies to map the nectin-4 binding interface on TIGIT. Using surface plasmon resonance, we deduced that TIGIT recognizes the membrane distal ectodomain of nectin-4 and the interaction is weaker than the well-characterized TIGIT: nectin-2 interaction. Deciphering the molecular basis of this newly identified interaction between TIGIT and nectin-4 will provide us important insight into the manipulation of this inhibitory signaling pathway, especially targeting cancer cells overexpressing nectin-4 that evade the immune surveillance of the body.

RNA-Sequencing Analysis Indicates That N-Cadherin Promotes Prostate Cancer Progression by the Epigenetic Modification of Key Genes

N-cadherin (cadherin-2 [CDH2]) is widely known as the promoter of prostate cancer (PCa) invasion and castration resistance. However, the biological mechanism of N-cadherin in PCa progression is unclear. In this study, we overexpressed N-cadherin in LNCaP cells and downregulated N-cadherin in PC3 cells by lentiviral transduction. Then, differentially expressed genes (DEGs) and dysregulated biological functions were investigated through RNA sequencing (RNA-seq) analyses. We found 13 long noncoding RNA (lncRNA) transcripts, 72 messenger RNA (mRNA) transcripts, and 3 integrated genes were dysregulated by N-cadherin. In the disease enrichment, bone cancer, and neurodegenerative and nervous system diseases were associated with N-cadherin in the circular RNA (circRNA; PC3 versus [vs.,/] LNCaP [PC3/LNCaP] comparison) and DEG analysis (LNCaP_oe_CDH2 vs. LNCaP_oe_NC [LNCaP_oe_CDH2/NC] comparison). Epigenetic reprogramming, such as nucleic acid binding, and chromatin and histone modifications, was enriched in Gene Ontology (GO) analysis (DEGs in LNCaP_oe_CDH2/NC and PC3_sh_NC/CDH2, and host genes of circRNA in PC3/LNCaP). Transcriptional misregulation in cancer, post-translational protein modification, gene expression, and generic transcription pathways were dysregulated in the pathway enrichment analysis (host genes of circRNA in PC3/LNCaP, and DEGs in LNCaP_oe_CDH2/NC and PC3_sh_NC/CDH2). Verifying DEGs through TCGA-PRAD dataset revealed six oncogenes (ARHGEF1, GRAMD1A, GTF2H4, MAPK8IP3, POLD1, and PTBP1) that were commonly upregulated by N-cadherin and in advanced PCa stages. In summary, we identified several oncogenes and biological functions associated with N-cadherin expression in PCa cells. N-cadherin may trigger epigenetic reprogramming in PCa cells to promote tumor progression.

Clinical Significance of Nectins in HCC and Other Solid Malignant Tumors: Implications for Prognosis and New Treatment Opportunities-A Systematic Review

The nectin family comprises four proteins, nectin-1 to -4, which act as cell adhesion molecules. Nectins have various regulatory functions in the immune system and can be upregulated or decreased in different tumors. The literature research was conducted manually by the authors using the PubMed database by searching articles published before 2023 with the combination of several nectin-related keywords. A total of 43 studies were included in the main section of the review. Nectins-1-3 have different expressions in tumors. Both the loss of expression and overexpression could be negative prognostic factors. Nectin-4 is the best characterized and the most consistently overexpressed in various tumors, which generally correlates with a worse prognosis. New treatments based on targeting nectin-4 are currently being developed. Enfortumab vedotin is a potent antibody-drug conjugate approved for use in therapy against urothelial carcinoma. Few reports focus on hepatocellular carcinoma, which leaves room for further studies comparing the utility of nectins with commonly used markers.

Nectins and Nectin-like molecules drive vascular development and barrier function

Angiogenesis, barriergenesis, and immune cell migration are all key physiological events that are dependent on the functional characteristics of the vascular endothelium. The protein family of Nectins and Nectin-like molecules (Necls) is a group of cell adhesion molecules that are widely expressed by different endothelial cell types. The family includes four Nectins (Nectin-1 to -4) and five Necls (Necl-1 to -5) that either interact with each other by forming homo- and heterotypical interactions or bind to ligands expressed within the immune system. Nectin and Necl proteins are mainly described to play a role in cancer immunology and in the development of the nervous system. However, Nectins and Necls are underestimated players in the formation of blood vessels, their barrier properties, and in guiding transendothelial migration of leukocytes. This review summarizes their role in supporting the endothelial barrier through their function in angiogenesis, cell-cell junction formation, and immune cell migration. In addition, this review provides a detailed overview of the expression patterns of Nectins and Necls in the vascular endothelium.

Communication between bone marrow mesenchymal stem cells and multiple myeloma cells: Impact on disease progression

Multiple myeloma (MM) is a hematological malignancy characterized by the accumulation of immunoglobulin-secreting clonal plasma cells at the bone marrow (BM). The interaction between MM cells and the BM microenvironment, and specifically BM mesenchymal stem cells (BM-MSCs), has a key role in the pathophysiology of this disease. Multiple data support the idea that BM-MSCs not only enhance the proliferation and survival of MM cells but are also involved in the resistance of MM cells to certain drugs, aiding the progression of this hematological tumor. The relation of MM cells with the resident BM-MSCs is a two-way interaction. MM modulate the behavior of BM-MSCs altering their expression profile, proliferation rate, osteogenic potential, and expression of senescence markers. In turn, modified BM-MSCs can produce a set of cytokines that would modulate the BM microenvironment to favor disease progression. The interaction between MM cells and BM-MSCs can be mediated by the secretion of a variety of soluble factors and extracellular vesicles carrying microRNAs, long non-coding RNAs or other molecules. However, the communication between these two types of cells could also involve a direct physical interaction through adhesion molecules or tunneling nanotubes. Thus, understanding the way this communication works and developing strategies to interfere in the process, would preclude the expansion of the MM cells and might offer alternative treatments for this incurable disease.

Genome-wide identification and skin expression of immunoglobulin superfamily in discus fish (Symphysodon aequifasciatus) reveal common genes associated with vertebrate lactation

Discus Symphysodon spp. employs an unusual parental care behavior where fry feed on parental skin mucus after hatching. Studies on discus immunoglobulin superfamily (IgSF) especially during parental care are scarce. Here, a total of 518 IgSF members were identified based on discus genome and clustered into 12 groups, unevenly distributing on 30 linkage groups. A total of 92 pairs of tandem duplication and 40 pairs of segmental duplication that underwent purifying selection were identified. IgSF genes expressed differentially in discus skin during different care stages and between male and female parents. Specifically, the transcription of btn1a1, similar with mammalian lactation, increased after spawning, reached a peak when fry started biting on parents' skin mucus, and then decreased. The expression of btn2a1 and other immune members, e.g., nect4, fcl5 and cd22, were up-regulated when fry stopped biting on mucus. These results suggest the expression differentiation of IgSF genes in skin of discus fish during parental care.

Antibody-drug conjugates and predictive biomarkers in advanced urothelial carcinoma

The use of antibody-drug conjugates (ADCs) is expanding in several malignancies, including urothelial carcinoma where two of these medications have been approved for use and several others remain under study. ADCs act by binding to specific cell surface proteins, delivering anticancer agents directly to the target cells. Preclinical studies suggest that loss of these surface proteins alters sensitivity to therapy and expression of target proteins vary significantly based on the tumor subtype, prior therapies and other characteristics. However, use of biomarkers to predict treatment response have not been regularly included in clinical trials and clinician practice. In this review we summarize what is known about potential predictive biomarkers for ADCs in UC and discuss potential areas where use of biomarkers may improve patient care.

Mechanism and function of miR-140 in human cancers: A review and in silico study

MicroRNA-140 (miR-140) acts as a tumor suppressor and plays a vital role in cell biological functions such as cell proliferation, apoptosis, and DNA repair. The expression of this miRNA has been shown to be considerably decreased in cancer tissues and cell lines compared with normal adjacent tissues. Consequently, aberrant expression of some miR-140 target genes can lead to the initiation and progression of various human cancers, such as breast cancer, gastrointestinal cancers, lung cancer, and prostate cancer. The dysregulation of the miR-140 network also affects cell proliferation, invasion, metastasis, and apoptosis of cancer cells by affecting various signaling pathways. Besides, up-regulation of miR-140 could enhance the efficacy of chemotherapeutic agents in different cancer. We aimed to cover most aspects of miR-140 function in cancer development and address its importance in different stages of cancer progression.

Nectins and Nectin-like Molecules in Colorectal Cancer: Role in Diagnostics, Prognostic Values, and Emerging Treatment Options: A Literature Review

In 2020, colorectal cancer was the third most common type of cancer worldwide with a clearly visible increase in the number of cases each year. With relatively high mortality rates and an uncertain prognosis, colorectal cancer is a serious health problem. There is an urgent need to investigate its specific mechanism of carcinogenesis and progression in order to develop new strategies of action against this cancer. Nectins and Nectin-like molecules are cell adhesion molecules that take part in a plethora of essential processes in healthy tissues as well as mediating substantial actions for tumor initiation and evolution. Our understanding of their role and a viable application of this in anti-cancer therapy has rapidly improved in recent years. This review summarizes the current data on the role nectins and Nectin-like molecules play in colorectal cancer.

Nectin4 is a potential therapeutic target for asthma

BACKGROUND

Nectins comprise a family of cellular adhesion molecules involved in Ca2+-independent cellular adhesion. Neither the biological significance nor clinical potential of Nectin4 for asthma has been investigated.

OBJECTIVES

The aims of this study were to elucidate the role of Nectin4 in airway inflammation and to determine the relationship between Nectin4 and clinical variables in patients with asthma.

METHODS

The relationship between Nectin4 levels in the blood of asthmatic patients and clinical variables was examined. Dermatophagoides pteronyssinus 1 (Der p1)-exposed normal human bronchial epithelial (NHBE) cells, and Nectin4-deficient (Nectin4-/-) and wild-type (WT) mice sensitized/challenged with ovalbumin (OVA), were used to investigate the involvement of Nectin4 in the pathogenesis of bronchial asthma via the Src/Rac1 pathway.

RESULTS

Plasma Nectin4 levels were significantly higher in asthmatic patients than controls and correlated with specific IgE D1, D2, lung function. The ROC curves for Nectin4 levels differed between asthma patients and controls. Nectin4/Afadin and Src/Rac1 levels were significantly increased in NHBE cells exposed to Der p1, but decreased in NHBE cells treated with Nectin4 siRNA. Airway obstruction and inflammation, as well as the levels of Th2 cytokines, Nectin4, and Src/Rac1, were increased in WT OVA/OVA mice compared with WT sham mice. Nectin4 knockdown resulted in lower levels of Afadin and Src/Rac1 in Nectin4-/-OVA/OVA than WT OVA/OVA mice.

CONCLUSION

These results suggest that Nectin4 is involved in airway inflammation and may be a therapeutic target in patients with asthma.

Comprehensive Relationship Analysis of the Long Noncoding RNAs (lncRNAs) and the Target mRNAs in Response to the Infection of Edwardsiella anguillarum in European eel (Anguilla anguilla) Inoculated with Freund's Adjuvant

Freund's complete adjuvant (FCA) and incomplete adjuvant (FIA), generally applied in subunit fishery vaccine, have not been explored on the molecular mechanism of the non-specific immune enhancement. As long noncoding RNAs (lncRNAs) play vital regulating roles in various biological activities, in this study, we examined the genome-wide expression of transcripts in the liver of European eel (Anguilla anguilla, Aa) inoculated with FCA and FIA (FCIA) to elucidate the regulators of lncRNAs in the process of Edwardsiella anguillarum (Ea) infection and Aa anti-Ea infection using strand-specific RNA-seq. After eels were challenged by Ea at 28 days post the first inoculation (dpi), compared to the control uninfected eels (Li group), the control infected eels (Con_Li group) showed severe bleeding, hepatocyte atrophy, and thrombi formed in the hepatic vessels of the liver, although eels inoculated with FCIA (FCIA_Li group) also formed slight thrombi in the hepatic vessels. Compared to the FCIA_Li group, there was about 10 times colony-forming unit (cfu) in the Con_Li group per 100 μg liver tissue, and the relative percent survival (RPS) of eels was 50% in FCIA_Li vs Con_Li. Using high-throughput transcriptomics, differential expressed genes (DEGs) and transcripts were identified and the results were verified using fluorescence real-time polymerase chain reaction (qRT-PCR). Interactions between the differential expressed lncRNAs (DE-lncRNAs) and the target DEGs were explored using Cytoscape according to their co-expression and co-location relationship. We found 13,499 lncRNAs (10,176 annotated and 3423 novel lncRNAs) between 3 comparisons of Con_Li vs Li, FCIA_Li vs Li, and FCIA_Li vs Con_Li, of which 111, 110, and 129 DE-lncRNAs were ascertained. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of DEGs targeted by DE-lncRNAs revealed these DEGs mainly involved in single-organism cellular process in BP, membrane in CC and binding in MF, and KEGG pathways showed that the target DEGs in co-expression and co-location enriched in cell adhesion molecules. Finally, 118 DE-lncRNAs target 1161 DEGs were involved in an interaction network of 8474 co-expression and 333 co-location-related links, of which 16 DE-lncRNAs play vital roles in anti-Ea infection. Taken together, the interaction networks revealed that DE-lncRNAs underlies the process of Ea infection and Aa anti-Ea infection.

Mechanotransduction through adhesion molecules: Emerging roles in regulating the stem cell niche

Stem cells have been shown to play an important role in regenerative medicine due to their proliferative and differentiation potential. The challenge, however, lies in regulating and controlling their potential for this purpose. Stem cells are regulated by growth factors as well as an array of biochemical and mechanical signals. While the role of biochemical signals and growth factors in regulating stem cell homeostasis is well explored, the role of mechanical signals has only just started to be investigated. Stem cells interact with their niche or to other stem cells via adhesion molecules that eventually transduce mechanical cues to maintain their homeostatic function. Here, we present a comprehensive review on our current understanding of the influence of the forces perceived by cell adhesion molecules on the regulation of stem cells. Additionally, we provide insights on how this deeper understanding of mechanobiology of stem cells has translated toward therapeutics.

Bioselectivity of silk protein-based materials and their bio-inspired applications

Adhesion to material surfaces is crucial for almost all organisms regarding subsequent biological responses. Mammalian cell attachment to a surrounding biological matrix is essential for maintaining their survival and function concerning tissue formation. Conversely, the adhesion and presence of microbes interferes with important multicellular processes of tissue development. Therefore, tailoring bioselective, biologically active, and multifunctional materials for biomedical applications is a modern focus of biomaterial research. Engineering biomaterials that stimulate and interact with cell receptors to support binding and subsequent physiological responses of multicellular systems attracted much interest in the last years. Further to this, the increasing threat of multidrug resistance of pathogens against antibiotics to human health urgently requires new material concepts for preventing microbial infestation and biofilm formation. Thus, materials exhibiting microbial repellence or antimicrobial behaviour to reduce inflammation, while selectively enhancing regeneration in host tissues are of utmost interest. In this context, protein-based materials are interesting candidates due to their natural origin, biological activity, and structural properties. Silk materials, in particular those made of spider silk proteins and their recombinant counterparts, are characterized by extraordinary properties including excellent biocompatibility, slow biodegradation, low immunogenicity, and non-toxicity, making them ideally suited for tissue engineering and biomedical applications. Furthermore, recombinant production technologies allow for application-specific modification to develop adjustable, bioactive materials. The present review focusses on biological processes and surface interactions involved in the bioselective adhesion of mammalian cells and repellence of microbes on protein-based material surfaces. In addition, it highlights the importance of materials made of recombinant spider silk proteins, focussing on the progress regarding bioselectivity.

CGX, a standardized herbal syrup, inhibits colon-liver metastasis by regulating the hepatic microenvironments in a splenic injection mouse model

Background: Colon-liver metastasis is observed in approximately 50% of patients with colorectal cancer and is a critical risk factor for a low survival rate. Several clinical studies have reported that colon-liver metastasis is accelerated by pathological hepatic microenvironments such as hepatic steatosis or fibrosis. Chunggan syrup (CGX), a standardized 13-herbal mixture, has been prescribed to patients with chronic liver diseases, including fatty liver, inflammation and fibrotic change, based on preclinical and clinical evidence.

Aim of the study: In the present study, we investigated anti-liver metastatic the effects of CGX in a murine colon carcinoma (MC38)-splenic injection mouse model.

Materials and methods: C57BL/6N mice were administered with CGX (100, 200 or 400 mg/kg) for 14 days before or after MC38-splenic injection under normal and high-fat diet (HFD) fed conditions. Also, above experiment was repeated without MC38-splenic injection to explore underlying mechanism.

Results: The number of tumor nodules and liver weight with tumors were sup-pressed by preadministration of CGX in both normal and HFD fed mice. Regarding its mechanisms, we found that CGX administration significantly activated epithelial-cadherin (E-cadherin), but decreased vascular endothelial-cadherin (VE-cadherin) in hepatic tissues under MC38-free conditions. In addition, CGX administration significantly reduced hepatic steatosis, via modulation of lipolytic and lipogenic molecules, including activated adenosine monophosphate activated protein kinase (AMPK) and peroxisome proliferator activated receptor-alpha (PPARα).

Conclusion: The present data indicate that CGX exerts an anti-colon-liver metastatic property via modulation of hepatic lipid related microenvironments.

An update on antibody-drug conjugates in urothelial carcinoma: state of the art strategies and what comes next

In recent years, considerable progress has been made in increasing the knowledge of tumour biology and drug resistance mechanisms in urothelial cancer. Therapeutic strategies have significantly advanced with the introduction of novel approaches such as immune checkpoint inhibitors and Fibroblast Growth Factor Receptor inhibitors. However, despite these novel agents, advanced urothelial cancer is often still progressive in spite of treatment and correlates with a poor prognosis. The introduction of antibody–drug conjugates consisting of a target-specific monoclonal antibody covalently linked to a payload (cytotoxic agent) is a novel and promising therapeutic strategy. In December 2019, the US Food and Drug Administration (FDA) granted accelerated approval to the nectin-4-targeting antibody–drug conjugate, enfortumab vedotin, for the treatment of advanced or metastatic urothelial carcinomas that are refractory to both immune checkpoint inhibitors and platinum-based treatment. Heavily pre-treated urothelial cancer patients reported a significant, 40% response to enfortumab vedotin while other antibody–drug conjugates are currently still under investigation in several clinical trials. We have comprehensively reviewed the available treatment strategies for advanced urothelial carcinoma and outlined the mechanism of action of antibody–drug conjugate agents, their clinical applications, resistance mechanisms and future strategies for urothelial cancer.

Nectin-4 promotes osteosarcoma progression and metastasis through activating PI3K/AKT/NF-κB signaling by down-regulation of miR-520c-3p

Purpose

Nectin-4 is specifically up-regulated in various tumors, exert crucial effects on tumor occurrence and development. Nevertheless, the role and molecular mechanism of Nectin-4 in osteosarcoma (OS) are rarely studied.

Methods

The expression of Nectin-4 and its relationship with clinical characteristics of OS were investigated using OS clinical tissues, tissue microarrays, TCGA, and GEO databases. Moreover, the effect of Nectin-4 on cell growth and mobility was detected by CCK-8, colony formation, transwell, and wound-healing assays. The RT-qPCR, Western blotting, and luciferase reporter assays were performed to explore molecular mechanisms through which Nectin-4 mediates the expression of miR-520c-3p, thus modulating PI3K/AKT/NF-κB signaling. In vivo mice models constructed by subcutaneous transplantation and tail vein injection were used to validate the functional roles of Nectin-4 and miR-520c-3p.

Results

Nectin-4 displayed a higher expression in OS tumor tissues compared with normal tissues, and its overexpression was positively associated with tumor stage and metastasis in OS patients. Functionally, Nectin-4 enhanced OS cells growth and mobility in vitro. Mechanistically, Nectin-4 down-regulated the levels of miR-520c-3p that directly targeted AKT-1 and P65, thus leading to the stimulation of PI3K/AKT/NF-κB signaling. In addition, the expression of miR-520c-3p was apparently lower in OS tissues than in normal tissues, and its low expression was significantly related to tumor metastasis. Furthermore, ectopic expression of miR-520c-3p markedly blocked the effect of Nectin-4 on OS cell growth and mobility. Knockdown of Nectin-4 could suppress the tumorigenesis and metastasis in vivo, which could be remarkably reversed by miR-520c-3p silencing.

Conclusions

Nectin-4 as an oncogene can promote OS progression and metastasis by activating PI3K/AKT/NF-κB signaling via down-regulation of miR-520c-3p, which could represent a novel avenue for identifying a potential therapeutic target for improving patient outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02669-w.

Heterophilic recognition between E-cadherin and N-cadherin relies on same canonical binding interface as required for E-cadherin homodimerization

Cadherins are a family of cell surface glycoproteins that mediate Ca²⁺-dependent cell to cell adhesion. They organize to form large macromolecular assemblies at the junctions of cells in order to form and maintain the integrity of tissue structures, thereby playing an indispensable role in the multicellular organization. Notably, a large body of research on E- and N-cadherin, the two most widely studied members of the cadherin superfamily, suggest for homophilic associations among them to drive cell adhesion. Interestingly, latest studies also highlight for direct crosstalk among these two classical cadherins to form heterotypic connections in physiological as well as in disease environment. However, the molecular details for the heterophilic association of E-cadherin and N-cadherin has not been investigated yet, which we aimed to address in this work. Using surface plasmon resonance and flow cytometry based biophysical studies we observed heterophilic interaction between E- and N-cadherin mediated through the membrane distal ectodomains. Further, the heterodimeric interface of E-cadherin and N-cadherin was mapped using structure-guided mutational studies followed by complementary biophysical analyses to identify the important interface residues involved in the interaction. The results obtained imply significant resemblance in the interface residues of E-cadherin that are crucial for homophilic recognition of E-cadherin and heterophilic recognition of N-cadherin as well.

A novel strategy for treatment of bladder cancer: Antibody-drug conjugates

In the past, there was no second-line chemotherapeutic agent suitable for use when urothelial carcinoma (UC) progressed to platinum-resistant UC. However, recently, several new treatment options, such as immune checkpoint inhibitors or targeted therapy have shifted the treatment paradigm regarding second-line therapeutic modalities. A novel class of therapeutic agents includes an antibody-drug conjugate (ADC). ADCs consist of three characteristics: a monoclonal antibody, linker, and payload. The specificity of the monoclonal antibody facilitates the delivery of a linked cytotoxic drug directly into the target tumor cell. Although various ADCs have been developed and approved for use in treating several solid tumors, almost all ADCs for the treatment of UC are still in the testing phase. Here, we review the key points about ADCs and summarize the novel ADCs that are approved or are involved in ongoing studies in UC.

Ancient Origins of Cytoskeletal Crosstalk: Spectraplakin-like Proteins Precede the Emergence of Cortical Microtubule Stabilization Complexes as Crosslinkers

Adhesion between cells and the extracellular matrix (ECM) is one of the prerequisites for multicellularity, motility, and tissue specialization. Focal adhesions (FAs) are defined as protein complexes that mediate signals from the ECM to major components of the cytoskeleton (microtubules, actin, and intermediate filaments), and their mutual communication determines a variety of cellular processes. In this study, human cytoskeletal crosstalk proteins were identified by comparing datasets with experimentally determined cytoskeletal proteins. The spectraplakin dystonin was the only protein found in all datasets. Other proteins (FAK, RAC1, septin 9, MISP, and ezrin) were detected at the intersections of FAs, microtubules, and actin cytoskeleton. Homology searches for human crosstalk proteins as queries were performed against a predefined dataset of proteomes. This analysis highlighted the importance of FA communication with the actin and microtubule cytoskeleton, as these crosstalk proteins exhibit the highest degree of evolutionary conservation. Finally, phylogenetic analyses elucidated the early evolutionary history of spectraplakins and cortical microtubule stabilization complexes (CMSCs) as model representatives of the human cytoskeletal crosstalk. While spectraplakins probably arose at the onset of opisthokont evolution, the crosstalk between FAs and microtubules is associated with the emergence of metazoans. The multiprotein complexes contributing to cytoskeletal crosstalk in animals gradually gained in complexity from the onset of metazoan evolution.

Head-to-Head Comparison of the Expression Differences of NECTIN-4, TROP-2, and HER2 in Urothelial Carcinoma and Its Histologic Variants

Background

Antibody–drug conjugates (ADC), such as enfortumab vedotin (EV), sacituzumab govitecan (SG), and RC-48, have shown outstanding response rates to local advanced or metastatic urothelial carcinoma (UC). However, their corresponding target expression characteristics in UC and its histologic variants were unknown.

Methods

We detected the expression of NECTIN-4, TROP-2, and HER2, which are the corresponding targets of ADCs EV, SG, and RC-48 in muscle-invasive UC through immunohistochemistry.

Results

161 consecutive samples from 2017 to 2021 of muscle-invasive UC and its histologic variants were obtained in Peking University First Hospital. Variant histology types included 72UC, 10 squamous carcinomas, 23 glandular carcinomas, 19 small cell carcinomas, 19 micropapillary variants, and 18 nested variants. NECTIN-4 expression was found to be 57/72 (79.2%), 10/10 (100%), 15/23 (65.2%), 4/19 (21.1%), 15/19 (78.9%), and 16/18 (88.9%) in conventional UC, squamous carcinoma, glandular carcinoma, small cell carcinoma, micropapillary, and nested variant, respectively, compared with 65/72 (90.3%), 8/10 (80.0%), 13/23 (56.5%), 3/19 (15.8%), 16/19 (84.2%), and 15/18 (83.3%) of TROP-2, and 26/72 (36.1%), 0, 5/23 (21.7%), 6/19 (31.6%), 5/19 (26.3%), and 7/18 (38.9%) of HER2.

Clinical development of antibody-drug conjugates in triple negative breast cancer: Can we jump higher?

INTRODUCTION

Triple negative breast cancer (TNBC) is an aggressive BC subtype, associated with higher rates of relapse in the primary disease setting and shorter overall survival upon metastatic relapse. The advent of antibody-drug conjugates (ADC), able to deliver selectively potent chemotherapeutic agents, has demonstrated promising clinical activity, with the first approval of an ADC, i.e. Sacituzumab Govitecan, in the metastatic setting. The main scope of this paper is to provide the most recent data indicating the promise of this novel class of drugs, as potential tools to improve clinical outcomes of patients diagnosed with TNBC.

AREAS COVERED

In this article, upon review of the main characteristics of TNBC, and those of ADCs, an overview of the data from clinical trials assessing ADCs in TNBC will be provided, including those that led to the first approval of such a drug for patients with metastatic disease; furthermore, several other ADCs targeting different proteins (over)expressed by TNBC undergo clinical development. Combinations of ADCs with other targeted agents are discussed; the most pertinent considerations for improving the chances of successful clinical development of ADCs in TNBC are provided.

EXPERT OPINION

ADCs are a potent class of targeted anticancer assets, with demonstrated efficacy against metastatic TNBC. Such assets could further improve clinical outcomes of patients with TNBC, and successful development depends upon: i) successful triaging of patients with the right ADC, ii) technical optimization of ADCs to maximize the efficacy, while reducing toxicity, and iii) assess rationally chosen combinations with synergistic antitumor activity and acceptable safety profile.

Nectin-4: a Novel Therapeutic Target for Skin Cancers

OPINION STATEMENT

Nectin-4 is a tumor-associated antigen that is highly expressed on various cancer cells, and it has been further proposed to have roles in tumor development and propagation ranging from cellular proliferation to motility and invasion. Nectin-4 blockade reduces tumor proliferation and induces apoptosis in several malignancies. Nectin-4 has been used as a potential target in antibody-drug conjugate (ADC) development. Enfortumab vedotin, an ADC against Nectin-4, has demonstrated efficacy against solid tumor malignancies. Enfortumab vedotin has received US Food and Drug Administration approval for treating urothelial cancer. Furthermore, the efficacy of ADCs against Nectin-4 against solid tumors other than urothelial cancer has been demonstrated in preclinical studies, and clinical trials examining the effects of enfortumab vedotin are ongoing. Recently, Nectin-4 was reported to be highly expressed in several skin cancers, including malignant melanoma, cutaneous squamous cell carcinoma, and extramammary Paget's disease, and involved in tumor progression and survival in retrospective studies. Nectin-4-targeted therapies and ADCs against Nectin-4 could therefore be novel therapeutic options for skin cancers. This review highlights current knowledge on Nectin-4 in malignant tumors, the efficacy of enfortumab vedotin in clinical trials, and the prospects of Nectin-4-targeted agents against skin cancers.

Nectin-1 and Non-muscle Myosin Heavy Chain-IIB: Major Mediators of Herpes Simplex Virus-1 Entry Into Corneal Nerves

Herpes Simplex Virus 1 (HSV-1) invades corneal nerves upon its infection of the cornea and then establishes latency in the trigeminal ganglion (TG). The latent virus in TG is often reactivated and travels back to the cornea, causing recurrent herpes simplex keratitis (HSK). The entry of HSV-1 into the corneal nerve is considered the initial step of infection resulting in HSV-1 latency and HSK recurrence. Several gD and gB receptors have been identified, including nectin-1, herpes virus entry medium (HVEM) and 3-O-sulfated heparan sulfate (3-OS-HS) as gD receptors, and non-muscle myosin heavy chain IIA (NMHC-IIA), NMHC-IIB and myelin-associated glycoprotein (MAG) as gB receptors. However, which receptors contribute to the entry of HSV-1 into corneal nerves are yet to be determined. This study observed that receptors nectin-1, HVEM, 3-OS-HS, NMHC-IIA, and NMHC-IIB, not MAG, were expressed in healthy corneal nerves. Further, we cultured TG neurons extracted from mice in vitro to screen for functional gD/gB receptors. Both in vitro siRNA knockdown and in vivo antibody blocking of either nectin-1 or NMHC-IIB reduced the entry and the replication of HSV-1 as shown by qPCR analysis and immunofluorescence measure, respectively. Also, we observed that the re-localization and the upregulation expression of NMHC-IIB after HSV-1 exposure were inhibited when gD receptor nectin-1 was knocked down. These data suggest that nectin-1 was the main gD receptor and NMHC-IIB was the main gB receptor in mediating HSV-1 entry and hold promise as therapeutic targets for resolving HSV-1 latency and HSK recurrence.

Cadherin‑16 inhibits thyroid carcinoma cell proliferation and invasion

Cadherin-16 (CDH16), a member of the cadherin family of adhesion molecules, serves an important role in the formation and maintenance of the thyroid follicular lumen. Decreased expression of CDH16 has been reported to be associated with tumor stage in papillary thyroid cancer (PTC); however, previous analyses have been limited and the biological role of CDH16 in different subtypes of TC is unknown. To investigate the role of CDH16 in the occurrence and development of TC, bioinformatic analysis of three TC subtypes (PTC, follicular cell-derived TC and anaplastic TC) was performed using an extended data set from the Gene Expression Omnibus database, with additional confirmation using data from The Cancer Genome Atlas, as well as biopsies from 35 patients with PTC and TC or follicular cell lines. According to the dataset analysis, CDH16 was downregulated in PTC and follicular cell-derived and anaplastic TC; the downregulation in PTC was independent of DNA copy number variation. Furthermore, low expression levels of CDH16 were significantly correlated with tumor size, lymph node metastasis status and disease stage in 35 patients with PTC. Gene Set Enrichment Analysis suggested that CDH16 participated in DNA replication and cell adhesion pathways. To evaluate CDH16 activity, CDH16 was overexpressed in TC-derived BCPAP cells. CDH16 overexpression inhibited cell proliferation, migration and invasion and induced apoptosis by downregulating proteins associated with DNA replication and cell adhesion. These results support the identification of CDH16 as a valuable target for TC prognosis and therapy and, to the best of our knowledge, represent the first direct demonstration of its mechanistic role in TC.

Nectin cell adhesion molecule 4 regulates angiogenesis through Src signaling and serves as a novel therapeutic target in angiosarcoma

Angiosarcoma is a rare, life-threatening soft tissue sarcoma with malignant endothelial cells that is mainly found in the skin. Multidisciplinary approaches are used to treat patients with unresectable metastasized lesions; considering the cellular origin of angiosarcoma, anti-angiogenic therapy has also been used recently. However, these treatments have limited efficacy, and the survival rate remains low. Thus, more effective treatments need to be developed. Nectin cell adhesion molecule 4 (NECTIN4) is highly expressed in malignant tumors and promotes tumor progression. Thus, NECTIN4 is expected to be a novel therapeutic target for cancer. However, the significance of NECTIN4 in angiosarcoma remains unknown. Using immunohistochemistry, we investigated NECTIN4 expression in 74 tissue samples from angiosarcoma patients, finding variable NECTIN4 expression. In addition, we investigated NECTIN4 expression and function in human angiosarcoma cell lines. NECTIN4 expression was higher in angiosarcoma cells than normal endothelial cells, and angiosarcoma cells were sensitive to monomethyl auristatin E, the cytotoxic part of a NECTIN4-targetting antibody-drug conjugate. NECTIN4 knockdown inhibited the proliferation and angiogenesis of angiosarcoma cells, and Src kinase signaling was shown to be involved in NECTIN4 function, at least in part. NECTIN4-targeted therapy has the potential to be a novel treatment strategy for angiosarcoma.

The Anti-Nectin 4: A Promising Tumor Cells Target. A Systematic Review

The nectin cell adhesion protein 4 (Nectin-4) is overexpressed in multiple human malignancies. Such aberrant expression is correlated with cancer progression and poor prognostic. Nectin-4 has emerged as a potential biomarker and promising targeted therapy. This review aimed to gather the current state of the literature about Nectin-4 relevance in preclinical tumor models and to summarize its clinical relevance regarding cancer. A systematic assessment of literature articles was performed by searching in PUBMED (MEDLINE) from the database inception to May 2021, following PRISMA guidelines. Preclinical models unanimously demonstrated membrane and cytoplasmic location of the Nectin-4. Furthermore, Nectin-4 was overexpressed whatever the location of the solid tumors. Interestingly, a heterogeneity of Nectin-4 expression has been highlighted in bladder urothelial carcinoma. High serum Nectin-4 level was correlated with treatment efficiency and disease progression. Finally, generated Anti-drug-Conjugated targeting Nectin-4 induced cell death in multiple tumor cell lines. Nectin-4 emerge as a promising target for anti-cancer drugs development because of its central role in tumorigenesis, and lymphangiogenesis. Enfortumab vedotin targeting Nectin-4 demonstrated encouraging results and should be extended to other types of solid tumors.

Eph/Ephrin-Based Protein Complexes: The Importance of cis Interactions in Guiding Cellular Processes

Although intracellular signal transduction is generally represented as a linear process that transmits stimuli from the exterior of a cell to the interior via a transmembrane receptor, interactions with additional membrane-associated proteins are often critical to its success. These molecules play a pivotal role in mediating signaling via the formation of complexes in cis (within the same membrane) with primary effectors, particularly in the context of tumorigenesis. Such secondary effectors may act to promote successful signaling by mediating receptor-ligand binding, recruitment of molecular partners for the formation of multiprotein complexes, or differential signaling outcomes. One signaling family whose contact-mediated activity is frequently modulated by lateral interactions at the cell surface is Eph/ephrin (EphA and EphB receptor tyrosine kinases and their ligands ephrin-As and ephrin-Bs). Through heterotypic interactions in cis, these molecules can promote a diverse range of cellular activities, including some that are mutually exclusive (cell proliferation and cell differentiation, or adhesion and migration). Due to their broad expression in most tissues and their promiscuous binding within and across classes, the cellular response to Eph:ephrin interaction is highly variable between cell types and is dependent on the cellular context in which binding occurs. In this review, we will discuss interactions between molecules in cis at the cell membrane, with emphasis on their role in modulating Eph/ephrin signaling.

Computational Systems Biology of Morphogenesis

Extracting mechanistic knowledge from the spatial and temporal phenotypes of morphogenesis is a current challenge due to the complexity of biological regulation and their feedback loops. Furthermore, these regulatory interactions are also linked to the biophysical forces that shape a developing tissue, creating complex interactions responsible for emergent patterns and forms. Here we show how a computational systems biology approach can aid in the understanding of morphogenesis from a mechanistic perspective. This methodology integrates the modeling of tissues and whole-embryos with dynamical systems, the reverse engineering of parameters or even whole equations with machine learning, and the generation of precise computational predictions that can be tested at the bench. To implement and perform the computational steps in the methodology, we present user-friendly tools, computer code, and guidelines. The principles of this methodology are general and can be adapted to other model organisms to extract mechanistic knowledge of their morphogenesis.

The Systematic Landscape of Nectin Family and Nectin-Like Molecules: Functions and Prognostic Value in Low Grade Glioma

Objective: Nectin and nectin-like molecules (Necls) are molecules that are involved in cell–cell adhesion and other vital cellular processes. This study aimed to determine the expression and prognostic value of nectin and Necls in low grade glioma (LGG).

Materials and Methods: Differentially expressed nectin and Necls in LGG samples and the relationship of nectin family and Necls expression with prognosis, clinicopathological parameters, and survival were explored using The Cancer Genome Atlas (TCGA), the Chinese Glioma Genome Atlas (CGGA), and Repository of Molecular Brain Neoplasia Data (REMBRANDT) databases. Univariate and multivariate Cox analysis models were performed to construct the prognosis-related gene signature. Kaplan-Meier curves and time-dependent receiver operating characteristic (ROC) curves and multivariate Cox regression analysis, were utilized to evaluate the prognostic capacity of the four-gene signature. Gene ontology (GO)enrichment analysis and Gene Set Enrichment Analyses (GSEA) were performed to further understand the underlying molecular mechanisms. The Tumor Immune Estimation Resource (TIMER) was used to explore the relationship between the four-gene signature and tumor immune infiltration.

Results: Several nectin and Necls were differentially expressed in LGG. Kaplan–Meier survival analyses and Univariate Cox regression showed patients with high expression of NECTIN2 and PVR and low expression of CADM2 and NECTIN1 had worse prognosis among TCGA, CGGA, and REMBRANDT database. Then, a novel four-gene signature was built for LGG prognosis prediction. ROC curves, KM survival analyses, and multivariate COX regression indicated the new signature was an independent prognostic indicator for overall survival. Finally, GSEA and GO enrichment analyses revealed that immune-related pathways participate in the molecular mechanisms. The risk score had a strong negative correlation with tumor purity and data of TIMER showed different immune cell proportions (macrophage and myeloid dendritic cell) between high- and low-risk groups. Additionally, signature scores were positively related to multiple immune-related biomarkers (IL 2, IL8 and IFNγ).

Conclusion: Our results offer an extensive analysis of nectin and Necls levels and a four-gene model for prognostic prediction in LGG, providing insights for further investigation of CADM2, NECTIN1/2, and PVR as potential clinical and immune targets in LGG.

Nectin cell adhesion molecule-4 (NECTIN-4): A potential target for cancer therapy

NECTIN-4 [a poliovirus receptor-related-4 (pvrl-4) encoded protein] is a Ca2+ independent immunoglobulin-like protein. Along with other Nectins (Nectin-1, -2 and -3), it is primarily involved in cell-cell adhesion. In contrast to other Nectins, Nectin-4 is specifically enriched in the embryonic and placental tissues but its expression significantly declines in adult life. In recent years, it has been found that Nectin-4 is especially overexpressed and served as a tumor associated inducer in various malignant tumors including breast, lung, colorectal, pancreatic, ovarian cancers etc. Over-expression of Nectin-4 is associated with various aspects of tumor progression like proliferation, angiogenesis, epithelial to mesenchymal transition, metastasis, DNA repair, tumor relapse, poor prognosis in several types of cancer. This review systematically highlights the implications of Nectin-4 in every possible aspect of cancer and the molecular mechanism of Nectin-4 mediated cancer progression. We have further emphasized on the therapeutic strategies that are being proposed to specifically target Nectin-4.

BT7480, a novel fully synthetic Bicycle tumor-targeted immune cell agonist™ (Bicycle TICA™) induces tumor localized CD137 agonism

Background

CD137 (4-1BB) is an immune costimulatory receptor with high therapeutic potential in cancer. We are creating tumor target-dependent CD137 agonists using a novel chemical approach based on fully synthetic constrained bicyclic peptide (Bicycle®) technology. Nectin-4 is overexpressed in multiple human cancers that may benefit from CD137 agonism. To this end, we have developed BT7480, a novel, first-in-class, Nectin-4/CD137 Bicycle tumor-targeted immune cell agonist™ (Bicycle TICA™).

Methods

Nectin-4 and CD137 co-expression analyses in primary human cancer samples was performed. Chemical conjugation of two CD137 Bicycles to a Nectin-4 Bicycle led to BT7480, which was then evaluated using a suite of in vitro and in vivo assays to characterize its pharmacology and mechanism of action.

Results

Transcriptional profiling revealed that Nectin-4 and CD137 were co-expressed in a variety of human cancers with high unmet need and spatial proteomic imaging found CD137-expressing immune cells were deeply penetrant within the tumor near Nectin-4-expressing cancer cells. BT7480 binds potently, specifically, and simultaneously to Nectin-4 and CD137. In co-cultures of human peripheral blood mononuclear cells and tumor cells, this co-ligation causes robust Nectin-4-dependent CD137 agonism that is more potent than an anti-CD137 antibody agonist. Treatment of immunocompetent mice bearing Nectin-4-expressing tumors with BT7480 elicited a profound reprogramming of the tumor immune microenvironment including an early and rapid myeloid cell activation that precedes T cell infiltration and upregulation of cytotoxicity-related genes. BT7480 induces complete tumor regressions and resistance to tumor re-challenge. Importantly, antitumor activity is not dependent on continuous high drug levels in the plasma since a once weekly dosing cycle provides maximum antitumor activity despite minimal drug remaining in the plasma after day 2. BT7480 appears well tolerated in both rats and non-human primates at doses far greater than those expected to be clinically relevant, including absence of the hepatic toxicity observed with non-targeted CD137 agonists.

Conclusion

BT7480 is a highly potent Nectin-4-dependent CD137 agonist that produces complete regressions and antitumor immunity with only intermittent drug exposure in syngeneic mouse tumor models and is well tolerated in preclinical safety species. This work supports the clinical investigation of BT7480 for the treatment of cancer in humans.