The ADAMs family of proteases as targets for the treatment of cancer

New insights into the function and pathophysiology of the ectodomain sheddase A Disintegrin And Metalloproteinase 10 (ADAM10)

The 'A Disintegrin And Metalloproteinase 10' (ADAM10) has gained considerable attention due to its discovery as an 'α-secretase' involved in the nonamyloidogenic processing of the amyloid precursor protein, thereby possibly preventing the excessive generation of the amyloid beta peptide, which is associated with the pathogenesis of Alzheimer's disease. ADAM10 was found to exert many additional functions, cleaving about 100 different membrane proteins. ADAM10 is involved in many pathophysiological conditions, ranging from cancer and autoimmune disorders to neurodegeneration and inflammation. ADAM10 cleaves its substrates close to the plasma membrane, a process referred to as ectodomain shedding. This is a central step in the modulation of the functions of cell adhesion proteins and cell surface receptors. ADAM10 activity is controlled by transcriptional and post-translational events. The interaction of ADAM10 with tetraspanins and the way they functionally and structurally depend on each other is another topic of interest. In this review, we will summarize findings on how ADAM10 is regulated and what is known about the biology of the protease. We will focus on novel aspects of the molecular biology and pathophysiology of ADAM10 that were previously poorly covered, such as the role of ADAM10 on extracellular vesicles, its contribution to virus entry, and its involvement in cardiac disease, cancer, inflammation, and immune regulation. ADAM10 has emerged as a regulator controlling cell surface proteins during development and in adult life. Its involvement in disease states suggests that ADAM10 may be exploited as a therapeutic target to treat conditions associated with a dysfunctional proteolytic activity.

The multifaceted role of proteases and modern analytical methods for investigation of their catalytic activity

We discuss the diverse functions of proteases in the context of their biotechnological and medical significance, as well as analytical approaches used to determine the functional activity of these enzymes. An insight into modern approaches to studying the kinetics and specificity of proteases, based on spectral (absorption, fluorescence), mass spectrometric, immunological, calorimetric, and electrochemical methods of analysis is given. We also examine in detail electrochemical systems for determining the activity and specificity of proteases. Particular attention is given to exploring innovative electrochemical systems based on the detection of the electrochemical oxidation signal of amino acid residues, thereby eliminating the need for extra redox labels in the process of peptide synthesis. In the review, we highlight the main prospects for the further development of electrochemical systems for the study of biotechnologically and medically significant proteases, which will enable the miniaturization of the analytical process for determining the catalytic activity of these enzymes.

A Disintegrin and metalloproteinase carves T cell abnormalities and pathogenesis in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder impacting various organs, notably prevalent in women of reproductive age. This review explores the involvement of a disintegrin and metalloproteinases (ADAMs) in SLE pathogenesis. Despite advancements in understanding SLE through genome and transcriptome studies, the role of ADAMs in post-translational regulations remains insufficiently explored. ADAMs, transmembrane proteins with diverse functions, impact cell adhesion, migration, and inflammation by shedding cell surface proteins, growth factors, and receptors. Notably, ADAM9 is implicated in Th17 cell differentiation, which is crucial in SLE pathology. ADAM10 and ADAM17 play pivotal roles in T-cell biology, influencing immune cell development and differentiation. Elevated soluble ADAM substrates in SLE patients serve as potential biomarkers correlating with disease activity. Targeting ADAMs or their substrates offers promising therapeutic avenues for SLE management and treatment enhancement.

Soluble receptors in cancer: mechanisms, clinical significance, and therapeutic strategies

Soluble receptors are soluble forms of receptors found in the extracellular space. They have emerged as pivotal regulators of cellular signaling and disease pathogenesis. This review emphasizes their significance in cancer as diagnostic/prognostic markers and potential therapeutic targets. We provide an overview of the mechanisms by which soluble receptors are generated along with their functions. By exploring their involvement in cancer progression, metastasis, and immune evasion, we highlight the importance of soluble receptors, particularly soluble cytokine receptors and immune checkpoints, in the tumor microenvironment. Although current research has illustrated the emerging clinical relevance of soluble receptors, their therapeutic applications remain underexplored. As the landscape of cancer treatment evolves, understanding and targeting soluble receptors might pave the way for novel strategies for cancer diagnosis, prognosis, and therapy.

Neutrophil-like pH-responsive pro-efferocytic nanoparticles improve neurological recovery by promoting erythrophagocytosis after intracerebral hemorrhage

Rationale: Intracerebral hemorrhage (ICH) is a devastating cerebrovascular disease resulting from blood extravasating into the brain parenchyma. Escalation of erythrophagocytosis (a form of efferocytosis), avoiding the consequent release of the detrimental erythrocyte lysates, may be a promising target of ICH management. The ADAM17 inhibitor and liver X receptor (LXR) agonist could promote efficient efferocytosis and injury repair. Nevertheless, the poor bioavailability and restriction of the blood-brain barrier (BBB) hinder their application. Therefore, it is needed that biocompatible and smart nanoplatforms were designed and synthesized to realize effective therapy targeting erythrophagocytosis. Methods: We first assessed the synergistic effect of therapeutic GW280264X (an ADAM17 inhibitor) and desmosterol (an LXR agonist) on erythrophagocytosis in vitro. Then a pH-responsive neutrophil membrane-based nanoplatform (NPEOz) served as a carrier to accurately deliver therapeutic GW280264X and desmosterol to the damaged brain was prepared via co-extrusion. Afterwards, their pH-responsive performance was valued in vitro and targeting ability was assessed through fluorescence image in vivo. Finally, the pro-erythrophagocytic and anti-neuroinflammatory ability of the nanomedicine and related mechanisms were investigated. Results: After the synergistical effect of the above two drugs on erythrophagocytosis was confirmed, we successfully developed neutrophil-disguised pH-responsive nanoparticles to efficiently co-deliver them. The nanoparticles could responsively release therapeutic agents under acidic environments, and elicit favorable biocompatibility and ability of targeting injury sites. D&G@NPEOz nanoparticles enhanced erythrophagocytosis through inhibiting shedding of the efferocytotic receptors MERTK/AXL mediated by ADAM17 and accelerating ABCA-1/ABCG-1-mediated cholesterol efflux regulated by LXR respectively. In addition, the nano-formulation was able to modulate the inflammatory microenvironment by transforming efferocytes towards a therapeutic phenotype with reducing the release of proinflammatory cytokines while increasing the secretion of anti-inflammatory factors, and improve neurological function. Conclusions: This biomimetic nanomedicine is envisaged to offer an encouraging strategy to effectively promote hematoma and inflammation resolution, consequently alleviate ICH progression.

Using siRNA Silencing to Analyze ADAM17 in Macrophages

Silencing expression with short interfering RNA (siRNA) is a rapid and cost-effective way to analyze the involvement of target genes in a range of biological processes. Here we describe isolation of primary human monocytes from peripheral blood and their in vitro differentiation to macrophages, followed by electroporation with siRNA to silence expression of a disintegrin and metalloproteinase 17 (ADAM17). This enables evaluation of ADAM17's role in cleaving transmembrane proteins, such as its prototypic substrate tumor necrosis factor (TNF), by enzyme-linked immunosorbent assay (ELISA), flow cytometry, or immunoblotting.

Insights into the Tumor Microenvironment-Components, Functions and Therapeutics

Similarly to our healthy organs, the tumor tissue also constitutes an ecosystem. This implies that stromal cells acquire an altered phenotype in tandem with tumor cells, thereby promoting tumor survival. Cancer cells are fueled by abnormal blood vessels, allowing them to develop and proliferate. Tumor-associated fibroblasts adapt their cytokine and chemokine production to the needs of tumor cells and alter the peritumoral stroma by generating more collagen, thereby stiffening the matrix; these processes promote epithelial-mesenchymal transition and tumor cell invasion. Chronic inflammation and the mobilization of pro-tumorigenic inflammatory cells further facilitate tumor expansion. All of these events can impede the effective administration of tumor treatment; so, the successful inhibition of tumorous matrix remodeling could further enhance the success of antitumor therapy. Over the last decade, significant progress has been made with the introduction of novel immunotherapy that targets the inhibitory mechanisms of T cell activation. However, extensive research is also being conducted on the stromal components and other cell types of the tumor microenvironment (TME) that may serve as potential therapeutic targets.

New tricks for an old pathway: emerging Notch-based biotechnologies and therapeutics

The Notch pathway regulates a diverse array of cell fate decisions, making it an enticing target in cancer therapy and regenerative medicine. During the early stages of Notch drug development, off-target toxicity precluded the approval of Notch inhibitors for the treatment of cancer. However, recent advances in our understanding of Notch structure and signaling have led to the development of several innovative Notch-based biotechnologies. In addition to new classes of inhibitors, pharmacological Notch activators have been shown to enhance osteogenesis and various aspects of T cell function. Furthermore, the mechanosensitive negative regulatory region (NRR) of the Notch receptor has been converted into synthetic Notch (synNotch) receptors with fully customizable signaling circuits. We review emergent Notch-based compounds, biologics, and cell therapies while highlighting the challenges and opportunities they face on the path to clinical development.

Initial study of the detection of ADAM 10 in the urine of type-2 diabetic patients

Diabetes mellitus (DM) is a disease of civilization. If left untreated, it can cause serious complications and significantly shortens the life time. DM is one of the leading causes of end-stage renal disease (uremia) worldwide. Early diagnosis is a prerequisite for successful treatment, preferably before the first symptoms appear. In this paper, we describe the optimization and synthesis of the internally quenched fluorescent substrate disintegrin and metalloproteinase 10 (ADAM10). Using combinatorial chemistry methods with iterative deconvolution, the substrate specificity of the enzyme in non-primed and primed positions was determined. We used the ABZ-Lys-Ile-Ile-Asn-Leu-Lys-Arg-Tyr(3-NO2)-NH2 peptide to study ADAM10 activity in urine samples collected from patients diagnosed with type 2 diabetes, compared to urine samples from healthy volunteers. The proteolytically active enzyme was present in diabetes samples, while in the case of healthy people we did not observe any activity. In conclusion, our study provides a possible basis for further research into the potential role of ADAM10 in the diagnosis of type 2 diabetes.

Combined proteomics and CRISPR‒Cas9 screens in PDX identify ADAM10 as essential for leukemia in vivo

BACKGROUND

Acute leukemias represent deadly malignancies that require better treatment. As a challenge, treatment is counteracted by a microenvironment protecting dormant leukemia stem cells.

METHODS

To identify responsible surface proteins, we performed deep proteome profiling on minute numbers of dormant patient-derived xenograft (PDX) leukemia stem cells isolated from mice. Candidates were functionally screened by establishing a comprehensive CRISPR‒Cas9 pipeline in PDX models in vivo.

RESULTS

A disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) was identified as an essential vulnerability required for the survival and growth of different types of acute leukemias in vivo, and reconstitution assays in PDX models confirmed the relevance of its sheddase activity. Of translational importance, molecular or pharmacological targeting of ADAM10 reduced PDX leukemia burden, cell homing to the murine bone marrow and stem cell frequency, and increased leukemia response to conventional chemotherapy in vivo.

CONCLUSIONS

These findings identify ADAM10 as an attractive therapeutic target for the future treatment of acute leukemias.

Evaluation of Cisplatin-Induced Acute Renal Failure Amelioration Using Fondaparinux and Alteplase

Acute renal failure (ARF) is a deleterious condition with increased mortality or healthcare costs or dialysis-dependent end-stage renal disease. The study aims to compare prophylaxis with fondaparinux (Fund) vs. treatment with alteplase (Alt) in ameliorating cisplatin (Cis)-induced ARF. Sixty male mice were equally divided randomly into six groups of control, Cis, Alt, and Cis + Alt groups receiving normal saline for 10 days. All four groups except for the control received Cis (30 mg/kg, i.p.) on day 7, and 6 h later, both the Alt groups received Alt (0.9 mg/kg, i.v.). The animal groups Fund and Fund + Cis received Fund (5 mg/kg, i.p.) for 10 days, and the Fund + Cis group on day 7 received Cis. All the animal groups were euthanized 72 h after the Cis dose. The Fund + Cis group showed significantly increased expression levels of platelet count, retinoid X receptor alpha (RXR-α) and phosphorylated Akt (p-Akt) in addition to decreased levels of urea, blood urea nitrogen (BUN), uric acid, white blood cells (WBCs), red blood cells (RBCs), relative kidney body weight, kidney injury score, glucose, prothrombin (PT), A Disintegrin And Metalloproteinases-10 (ADAM10), extracellular matrix deposition, protease-activated receptor 2 (PAR-2), and fibrinogen expression when compared to the Cis-only group. Meanwhile, the Cis + Alt group showed increased caspase-3 expression in addition to decreased levels of urea, BUN, uric acid, WBCs, RBCs, glucose, platelet count and PT expression with a marked decrease in PAR-2 protein expression compared to the Cis group. The creatinine levels for both the Fund + Cis and Cis + Alt groups were found to be comparable to those of the Cis-only group. The results demonstrate that the coagulation system's activation through the stimulation of PAR-2 and fibrinogen due to Cis-induced ADAM10 protein expression mediated the apoptotic pathway, as indicated by caspase-3 expression through the p-Akt pathway. This is normally accompanied by the loss of RXR-α distal and proximal tubules as lipid droplets. When the animals were pre-treated with the anticoagulant, Fund, the previous deleterious effect was halted while the fibrinolytic agent, Alt, most of the time failed to treat Cis-induced toxicity.

Pan-cancer analysis of ADAMs: A promising biomarker for prognosis and response to chemotherapy and immunotherapy

Background: Members of a disintegrin and metalloproteinase (ADAM) family play a vital role in cancer development. However, a comprehensive analysis of the landscape of the ADAM family in pan-cancer remains to be performed.

Methods: The correlation of the expression level and prognostic value with ADAMs in a pan-cancer cohort and the relationship between ADAMs and the stemness score, tumour microenvironment (TME), chemotherapy-related drug sensitivity, immune subtype, and immunotherapy outcome were investigated.

Results: ADAMs were differentially expressed between tumour and para-carcinoma tissues in the pan-cancer cohort, and the expression of ADAMs was significantly correlated with patient prognosis. Furthermore, ADAMs were significantly correlated with the stromal score and immune score based on the TME analysis. Additionally, ADAMs were also correlated with DNAss and RNAss in the pan-cancer cohort. On investigating the CellMiner database, ADAMs were revealed to be significantly correlated with the sensitivity of various drugs, including raloxifene and tamoxifen. Moreover, in the IMvigor210 and GSE78220 cohorts, ADAMs were correlated with immunotherapy response and immune activation genes. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) were utilised to determine the differential level of ADAM9 in cancer and para-carcinoma tissues in patients’ samples.

Conclusion: This study elucidates the importance of ADAMs in cancer progression and lays a foundation for further exploration of ADAMs as potential pan-cancer targets.

The versatile roles of ADAM8 in cancer cell migration, mechanics, and extracellular matrix remodeling

The posttranslational proteolytic cleavage is a unique and irreversible process that governs the function and half-life of numerous proteins. Thereby the role of the family of A disintegrin and metalloproteases (ADAMs) plays a leading part. A member of this family, ADAM8, has gained attention in regulating disorders, such as neurogenerative diseases, immune function and cancer, by attenuating the function of proteins nearby the extracellular membrane leaflet. This process of "ectodomain shedding" can alter the turnover rate of a number of transmembrane proteins that function in cell adhesion and receptor signal transduction. In the past, the major focus of research about ADAMs have been on neurogenerative diseases, such as Alzheimer, however, there seems to be evidence for a connection between ADAM8 and cancer. The role of ADAMs in the field of cancer research has gained recent attention, but it has been not yet been extensively addressed. Thus, this review article highlights the various roles of ADAM8 with particular emphasis on pathological conditions, such as cancer and malignant cancer progression. Here, the shedding function, direct and indirect matrix degradation, effects on cancer cell mobility and transmigration, and the interplay of ADAM8 with matrix-embedded neighboring cells are presented and discussed. Moreover, the most probable mechanical impact of ADAM8 on cancer cells and their matrix environment is addressed and debated. In summary, this review presents recent advances in substrates/ligands and functions of ADAM8 in its new role in cancer and its potential link to cell mechanical properties and discusses matrix mechanics modifying properties. A deeper comprehension of the regulatory mechanisms governing the expression, subcellular localization, and activity of ADAM8 is expected to reveal appropriate drug targets that will permit a more tailored and fine-tuned modification of its proteolytic activity in cancer development and metastasis.

The immunological role of ADAMs in the field of gastroenterological chronic inflammatory diseases and cancers: a review

Metalloproteinases cleave transmembrane proteins that play critical roles in inflammation and cancers. Metalloproteinases include a disintegrin and metalloprotease (ADAM), which we previously examined using a fluorescence assay system, and described their association with resistance to systemic therapy in cancer patients. There are also many reports on the relation between ADAM expression and the prognosis of patients with gastroenterological chronic inflammatory diseases and cancers. Inhibiting their immunomodulating activity in chronic inflammation restores innate immunity and potentially prevents the development of various cancers. Among the numerous critical immune system-related molecules, we focus on major histocompatibility complex class I polypeptide-related sequence A (MICA), MICB, intracellular adhesion molecule (ICAM)-1, TNF-α, IL-6 receptor (IL-6R), and Notch. This review summarizes our current understanding of the role of ADAMs in gastroenterological diseases with regard to the immune system. Several Food and Drug Administration (FDA)-approved inhibitors of ADAMs have been identified, and potential therapies for targeting ADAMs in the treatment of chronic inflammatory diseases and cancers are discussed. Some ongoing clinical trials for cancers targeting ADAMs are also introduced.

In-silico evidence of ADAM metalloproteinase pathology in cancer signaling networks

Lack of effective targeted therapies often contributes to poor clinical outcomes of aggressive malignancies associated with drug resistance, angiogenesis and metastasis. Literature mining portrays the major role of ADAM17 in cancer and inflammatory diseases. However, it is quite challenging to design a candidate drug for targeting ADAM17 due to its structural similarity with the catalytic domain of the matrix metalloproteases (MMPs). The present study reports the protein-protein interaction analysis of ADAM17, along with the molecular docking and MD simulation studies for the screened compounds. Our analysis confirms the association of ADAM17 with numerous oncogenes that facilitates cancer progression and inflammation, especially the members of the Notch, receptor tyrosine kinase (RTK) and TNFα pathways. The outcome provides evidence that the prevalent protease ADAM17 could attribute to cancer signaling regulation though the shedding of various inflammatory and oncogenic molecules. We have also exploited the analogues of the existing inhibitors, with an aim at discovering a potent molecule, which could be repurposed as a drug against ADAM17 inflicted cancer progression. Upon stringent screening, we delineated our choice into two specific compounds (I6 and I9; analogues of IK862, a type of y-lactam hydroxamates), possessing the lowest binding energy (-9.1 Kcal/mol), stable MD-simulation studies and superior pharmacodynamic properties. The current information illustrates the avenue to persuade further research on targeting ADAM17 with small molecular compounds (I6 and I9) in cancer therapeutics.Communicated by Ramaswamy H. Sarma.

ADAM10 mediates shedding of carbonic anhydrase IX ectodomain non‑redundantly to ADAM17

Carbonic anhydrase IX (CA IX) is a transmembrane enzyme participating in adaptive responses of tumors to hypoxia and acidosis. CA IX regulates pH, facilitates metabolic reprogramming, and supports migration, invasion and metastasis of cancer cells. Extracellular domain (ECD) of CA IX can be shed to medium and body fluids by a disintegrin and metalloproteinase (ADAM) 17. Here we show for the first time that CA IX ECD shedding can be also executed by ADAM10, a close relative of ADAM17, via an overlapping cleavage site in the stalk region of CA IX connecting its exofacial catalytic site with the transmembrane region. This finding is supported by biochemical evidence using recombinant human ADAM10 protein, colocalization of ADAM10 with CA IX, ectopic expression of a dominant‑negative mutant of ADAM10 and RNA interference‑mediated suppression of ADAM10. Induction of the CA IX ECD cleavage with ADAM17 and/or ADAM10 activators revealed their additive effect. Similarly, additive effect was observed with an ADAM17‑inhibiting antibody and an ADAM10‑preferential inhibitor GI254023X. These data indicated that ADAM10 is a CA IX sheddase acting on CA IX non‑redundantly to ADAM17.

Role of metalloproteases in the CD95 signaling pathways

CD95L (also known as FasL or CD178) is a member of the tumor necrosis family (TNF) superfamily. Although this transmembrane ligand has been mainly considered as a potent apoptotic inducer in CD95 (Fas)-expressing cells, more recent studies pointed out its role in the implementation of non-apoptotic signals. Accordingly, this ligand has been associated with the aggravation of inflammation in different auto-immune disorders and in the metastatic occurrence in different cancers. Although it remains to decipher all key factors involved in the ambivalent role of this ligand, accumulating clues suggest that while the membrane bound CD95L triggers apoptosis, its soluble counterpart generated by metalloprotease-driven cleavage is responsible for its non-apoptotic functions. Nonetheless, the metalloproteases (MMPs and ADAMs) involved in the CD95L shedding, the cleavage sites and the different stoichiometries and functions of the soluble CD95L remain to be elucidated. To better understand how soluble CD95L triggers signaling pathways from apoptosis to inflammation or cell migration, we propose herein to summarize the different metalloproteases that have been described to be able to shed CD95L, their cleavage sites and the biological functions associated with the released ligands. Based on these new findings, the development of CD95/CD95L-targeting therapeutics is also discussed.

Therapeutic Potential of Targeting Regulated Intramembrane Proteolysis Mechanisms of Voltage-Gated Ion Channel Subunits and Cell Adhesion Molecules

Several integral membrane proteins undergo regulated intramembrane proteolysis (RIP), a tightly controlled process through which cells transmit information across and between intracellular compartments. RIP generates biologically active peptides by a series of proteolytic cleavage events carried out by two primary groups of enzymes: sheddases and intramembrane-cleaving proteases (iCLiPs). Following RIP, fragments of both pore-forming and non-pore-forming ion channel subunits, as well as immunoglobulin super family (IgSF) members, have been shown to translocate to the nucleus to function in transcriptional regulation. As an example, the voltage-gated sodium channel β1 subunit, which is also an IgSF-cell adhesion molecule (CAM), is a substrate for RIP. β1 RIP results in generation of a soluble intracellular domain, which can regulate gene expression in the nucleus. In this review, we discuss the proposed RIP mechanisms of voltage-gated sodium, potassium, and calcium channel subunits as well as the roles of their generated proteolytic products in the nucleus. We also discuss other RIP substrates that are cleaved by similar sheddases and iCLiPs, such as IgSF macromolecules, including CAMs, whose proteolytically generated fragments function in the nucleus. Importantly, dysfunctional RIP mechanisms are linked to human disease. Thus, we will also review how understanding RIP events and subsequent signaling processes involving ion channel subunits and IgSF proteins may lead to the discovery of novel therapeutic targets. SIGNIFICANCE STATEMENT: Several ion channel subunits and immunoglobulin superfamily molecules have been identified as substrates of regulated intramembrane proteolysis (RIP). This signal transduction mechanism, which generates polypeptide fragments that translocate to the nucleus, is an important regulator of gene transcription. RIP may impact diseases of excitability, including epilepsy, cardiac arrhythmia, and sudden death syndromes. A thorough understanding of the role of RIP in gene regulation is critical as it may reveal novel therapeutic strategies for the treatment of previously intractable diseases.

Oncogenic Role of ADAM32 in Hepatoblastoma: A Potential Molecular Target for Therapy

Outcomes of pediatric hepatoblastoma (HBL) have improved, but refractory cases still occur. More effective and safer drugs are needed that are based on molecular mechanisms. A disintegrin and metalloproteases (ADAMs) are expressed with high frequency in various human carcinomas and play an important role in cancer progression. In this study, we analyzed expression of ADAMs in HBL with a cDNA microarray dataset and found that the expression level of ADAM32 is particularly high. To investigate the role of ADAM32 in cancer, forced expression or knockdown experiments were conducted with HepG2 and HBL primary cells. Colony formation, cell migration and invasion, and cell viability were increased in HepG2 expressing ADAM32, whereas knockdown of ADAM32 induced a decrease in these cellular functions. Quantitative RT-PCR demonstrated an association between ADAM32 expression and the expression of genes related to cancer stem cells and epithelial–mesenchymal transition (EMT), suggesting a role of ADAM32 in cancer stemness and EMT. Furthermore, knockdown of ADAM32 increased cisplatin-induced apoptosis, and this effect was attenuated by a caspase-8 inhibitor, suggesting that ADAM32 plays a role in extrinsic apoptosis signaling. We conclude that ADAM32 plays a crucial role in progression of HBL, so it might be a promising molecular target in anticancer therapy.

ADAMDEC1 accelerates GBM progression via activation of the MMP2-related pathway

The ADAM (a disintegrin and metalloprotease) gene-related family including ADAM, ADAMTS, and ADAM-like decysin-1 has been reported to play an important role in the pathogenesis of multiple diseases, including cancers (lung cancer, gliomas, colorectal cancer, and gastrointestinal cancer). However, its biological role in gliomas remains largely unknown. Here, we aimed to investigate the biological functions and potential mechanism of ADAMDEC1 in gliomas. The mRNA and protein expression levels of ADAMDEC1 were upregulated in glioma tissues and cell lines. ADAMDEC1 showed a phenomenon of “abundance and disappear” expression in gliomas and normal tissues in that the higher the expression of ADAMDEC1 presented, the higher the malignancy of gliomas and the worse the prognosis. High expression of ADAMDEC1 was associated with immune response. Knockdown of ADAMDEC1 could decrease the proliferation and colony-forming ability of LN229 cells, whereas ADAMDEC1 overexpression has opposite effects in LN229 cells in vitro. Furthermore, we identified that ADAMDEC1 accelerates GBM progression via the activation of the MMP2 pathway. In the present study, we found that the expression levels of ADAMDEC1 were significantly elevated compared with other ADAMs by analyzing the expression levels of ADAM family proteins in gliomas. This suggests that ADAMDEC1 has potential as a glioma clinical marker and immunotherapy target.

The emerging role of furin in neurodegenerative and neuropsychiatric diseases

Furin is an important mammalian proprotein convertase that catalyzes the proteolytic maturation of a variety of prohormones and proproteins in the secretory pathway. In the brain, the substrates of furin include the proproteins of growth factors, receptors and enzymes. Emerging evidence, such as reduced FURIN mRNA expression in the brains of Alzheimer's disease patients or schizophrenia patients, has implicated a crucial role of furin in the pathophysiology of neurodegenerative and neuropsychiatric diseases. Currently, compared to cancer and infectious diseases, the aberrant expression of furin and its pharmaceutical potentials in neurological diseases remain poorly understood. In this article, we provide an overview on the physiological roles of furin and its substrates in the brain, summarize the deregulation of furin expression and its effects in neurodegenerative and neuropsychiatric disorders, and discuss the implications and current approaches that target furin for therapeutic interventions. This review may expedite future studies to clarify the molecular mechanisms of furin deregulation and involvement in the pathogenesis of neurodegenerative and neuropsychiatric diseases, and to develop new diagnosis and treatment strategies for these diseases.

Proteolysis dysfunction in the process of aging and age-related diseases

In this review, we discuss in detail the most relevant proteolytic systems that together with chaperones contribute to creating the proteostasis network that is kept in dynamic balance to maintain overall functionality of cellular proteomes. Data accumulated over decades demonstrate that the effectiveness of elements of the proteostasis network declines with age. In this scenario, failure to degrade misfolded or faulty proteins increases the risk of protein aggregation, chronic inflammation, and the development of age-related diseases. This is especially important in the context of aging-related modification of functions of the immune system.

MALAT1 in colorectal cancer: Its implication as a diagnostic, prognostic, and predictive biomarker

Metastasis Associated Lung Adenocarcinoma Transcript 1 (MALAT1), originally described as a prognostic biomarker remarkably linked with metastasis potential in lung cancer, has been identified as contributing to many diseases, including colorectal cancer (CRC). This long non-coding RNA (lncRNA) has come to the forefront of lncRNA research for its implications in cancer-related processes, such as cell proliferation and migration. In general, lncRNAs are recognized as enhancers, scaffolds, or decoys for a variety of oncogenes and tumor suppressors, although our understanding of lncRNA functions and mechanisms of action is still limited. Nowadays, cancer research is attracted to lncRNAs' ability to improve the early diagnosis of cancer, determine patients' prognosis, or predict therapy outcomes. In this review, we aimed to evaluate recent publications trying to uncover the cellular mechanisms of MALAT1-mediated regulation, and its potential exploitation in the management of CRC. The conclusions of this review provide robust support for the essential role of MALAT1 in CRC development and future personalized therapy.

Evaluation of Expression Of ADAM 10 as a Predictor of Lymph Node Metastasis in Oral Squamous Cell Carcinoma-An Immunohistochemical Study

BACKGROUND

Lymph node metastasis (LNM) is a well-known prognostic factor in Oral Squamous Cell Carcinoma(OSCC). A biological marker that predicts the Lymph Node Metastasis (LNM) in OSCC cases is the need of the hour. A Disintegrin And Metalloproteinases (ADAMs), a family of proteins that exhibit a metalloproteinase domain play a pivotal role in the pathogenesis of tumor growth and metastasis. This study aims to evaluate whether ADAM 10 can be used as a predictor of lymph node metastasis in OSCC using immunohistochemistry.

METHOD

A total of 90 samples that were categorized into 3 groups were included in the present study. Group I consisted of 30 samples of the normal oral mucosa, and Group II consisted of 30 samples of OSCC without lymph node metastasis. Group III consisted of 30 samples of OSCC with lymph node metastasis. Esophageal Squamous Cell Carcinoma was used as external positive control. Immunohistochemical expression of ADAM10 in their corresponding stained sections was assessed and staining intensity was calculated.

RESULTS

ADAM10 immunoreactivity was considered positive when located in cytoplasm or membrane or both. This method is similar to that used by Bamane et al. for OSCC cases. The mean value of the Staining Index score "AxB" was highest in Group III (7.90), followed by Group II (3.13) and least in Group I (0.27). These values were statistically significant.

CONCLUSION

Considering the findings of a higher percentage of ADAM10 positive cells, higher staining intensity, and higher staining index, the overexpression of ADAM10 can be used as an independent marker for OSCC patients to predict the lymph node metastasis.

Baseline soluble MICA levels act as a predictive biomarker for the efficacy of regorafenib treatment in colorectal cancer

Background

To evaluate the effect of regorafenib on soluble MHC class I polypeptide-related sequence A (MICA) (sMICA) level in vitro. In addition, we clinically examined whether its plasma levels were associated with regorafenib activity in terms of progression-free survival (PFS) in patients with CRC.

Methods

Human CRC cell line HCT116 and HT29 cells were treated with regorafenib and its pharmacologically active metabolites, M2 or M5 at the same concentrations as those in sera of patients. We also examined the sMICA levels and the area under the plasma concentration–time curve of regorafenib, M2 and M5.

Results

Regorafenib, M2, and M5 significantly suppressed shedding of MICA in human CRC cells without toxicity. This resulted in the reduced production of sMICA. In the clinical examination, patients with CRC who showed long median PFS (3.7 months) had significantly lower sMICA levels than those with shorter median PFS (1.2 months) (p = 0.045).

Conclusions

MICA is an attractive agent for manipulating the immunological control of CRC and baseline sMICA levels could be a predictive biomarker for the efficacy of regorafenib treatment.

Ars moriendi: Proteases as sculptors of cellular suicide

The Ars moriendi, which translates to "The Art of Dying," encompasses two Latin texts that gave advice on how to die well and without fear according to the Christian precepts of the late Middle Ages. Given that ten to hundred billion cells die in our bodies every day, it is obvious that the concept of a well and orderly ("regulated") death is also paramount at the cellular level. In apoptosis, as the most well-studied form of regulated cell death, proteases of the caspase family are the central mediators. However, caspases are not the only proteases that act as sculptors of cellular suicide, and therefore, we here provide an overview of the impact of proteases in apoptosis and other forms of regulated cell death.

Hybrid/Atypical Forms of Circulating Tumor Cells: Current State of the Art

Cancer is one of the most common diseases worldwide, and its treatment is associated with many challenges such as drug and radioresistance and formation of metastases. These difficulties are due to tumor heterogeneity, which has many causes. One may be the cell fusion, a process that is relevant to both physiological (e.g., wound healing) and pathophysiological (cancer and viral infection) processes. This literature review aimed to summarize the existing data on the hybrid/atypical forms of circulating cancer cells and their role in tumor progression. For that, the bioinformatics search in universal databases, such as PubMed, NCBI, and Google Scholar was conducted by using the keywords “hybrid cancer cells”, “cancer cell fusion”, etc. In this review the latest information related to the hybrid tumor cells, theories of their genesis, characteristics of different variants with data from our own researches are presented. Many aspects of the hybrid cell research are still in their infancy. However, with the level of knowledge already accumulated, circulating hybrids such as CAML and CHC could be considered as promising biomarkers of cancerous tumors, and even more as a new approach to cancer treatment.

MicroRNAs and Corresponding Targets in Esophageal Cancer as Shown In Vitro and In Vivo in Preclinical Models

Squamous cell carcinoma of the esophagus is associated with a dismal prognosis. Therefore, identification of new targets and implementation of new treatment modalities are issues of paramount importance. Based on a survey of the literature, we identified microRNAs conferring antitumoral activity in preclinical in vivo experiments. In the category of miRs targeting secreted factors and transmembrane receptors, four miRs were up-regulated and 10 were down-regulated compared with five out of nine in the category transcription factors, and six miRs were down-regulated in the category enzymes, including metabolic enzymes. The down-regulated miRs have targets which can be inhibited by small molecules or antibody-related entities, or re-expressed by reconstitution therapy. Up-regulated miRs have targets which can be reconstituted with small molecules or inhibited with antagomirs.

Validating Cell Surface Proteases as Drug Targets for Cancer Therapy: What Do We Know, and Where Do We Go?

Simple Summary

Cell surface proteases (so-called ectoproteases) are associated with cancer, and their targeting may confer valuable options for the improvement of cancer treatment outcome. Over the past 20 years, the permanent development of a multitude of inhibitors against several ectoproteases (including DPP4, FAP, APN, ADAM17, MMP2, and MMP9) has made it into clinical evaluation in haematological and solid tumours. Among them, a few show some efficacy, albeit limited, to cure cancer in the near future. This Review summarizes the efforts thus far undertaken in the development of ectoprotease inhibitors and highlights new directions for targeting ectoproteases as an additional weapon in the fight against cancer.

Abstract

Cell surface proteases (also known as ectoproteases) are transmembrane and membrane-bound enzymes involved in various physiological and pathological processes. Several members, most notably dipeptidyl peptidase 4 (DPP4/CD26) and its related family member fibroblast activation protein (FAP), aminopeptidase N (APN/CD13), a disintegrin and metalloprotease 17 (ADAM17/TACE), and matrix metalloproteinases (MMPs) MMP2 and MMP9, are often overexpressed in cancers and have been associated with tumour dysfunction. With multifaceted actions, these ectoproteases have been validated as therapeutic targets for cancer. Numerous inhibitors have been developed to target these enzymes, attempting to control their enzymatic activity. Even though clinical trials with these compounds did not show the expected results in most cases, the field of ectoprotease inhibitors is growing. This review summarizes the current knowledge on this subject and highlights the recent development of more effective and selective drugs targeting ectoproteases among which small molecular weight inhibitors, peptide conjugates, prodrugs, or monoclonal antibodies (mAbs) and derivatives. These promising avenues have the potential to deliver novel therapeutic strategies in the treatment of cancers.

Muscular Metastasis of Hepatocellular Carcinoma: Case Report and Literature Review

There are few case reports of hepatocellular carcinoma (HCC) metastasis to the skeletal muscle. A 78-year-old man developed a mass in the right shoulder. Washout of contrast medium during contrast-enhanced ultrasonography (CEUS) in both the primary HCC and the metastatic site was detected. Several nodules were scattered throughout the liver on an autopsy. In addition, the moderately differentiated HCC had metastasized to the right teres major muscle. Rare muscular metastasis should be considered if a hepatic tumor is moderately or poorly differentiated HCC. Early washout during CEUS is consistent with a pathological diagnosis of moderately or poorly differentiated HCC.

The expression of ADAMTS14 is regulated by promoter DNA methylation and is associated with poor prognosis in colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant tumors of digestive system, and its main cause of death is tumor metastasis. The occurrence of CRC is a polygenic and multi-step complex process involving genetic and epigenetic alterations. It has been demonstrated that ADAMTS14 (A disintegrin and metalloproteinase with thrombospondin motifs 14) was hypermethylated in esophageal cancer using whole-genome methylation microarray in our previous report. The present study revealed that ADAMTS14 was highly methylated accompanied with low expression in CRC. In addition, demethylation agent 5-Aza-dC could demethylate ADAMTS14 promoter region and reactivate ADAMTS14 expression effectively in vitro. Therefore, promoter hypermethylation was probably contributed to ADAMTS14 epigenetic silencing in CRC. Furthermore, ADAMTS14 protein expression was higher at invasive tumor front than at the tumor center or other areas of tumor. Kaplan-meier survival analysis indicated that the high ADAMTS14 expression was correlated with poor prognosis in CRC patients, suggesting the possibility that ADAMTS14 is a promising indicator in the evaluation of CRC prognosis.

Discovery of Dimeric Arylsulfonamides as Potent ADAM8 Inhibitors

The metalloproteinase ADAM8 is upregulated in several cancers but has a dispensable function under physiological conditions. In tumor cells, ADAM8 is involved in invasion, migration, and angiogenesis. The use of bivalent inhibitors could impair migration and invasion through the double binding to a homodimeric form of ADAM8 located on the cell surface of tumor cells. Herein we report the rational design and synthesis of the first dimeric ADAM8 inhibitors selective over ADAM10 and matrix metalloproteinases. Bivalent derivatives have been obtained by dimerizing the structure of a previously described ADAM17 inhibitor, JG26. In particular, derivative 2 was shown to inhibit ADAM8 proteolytic activity in vitro and in cell-based assays at nanomolar concentration. Moreover, it was more effective than the parent monomeric compound in blocking invasiveness in the breast cancer MDA-MB-231 cell line, thus supporting our hypothesis about the importance of inhibiting the active homodimer of ADAM8.

Neuroprotective effect and potential of cellular prion protein and its cleavage products for treatment of neurodegenerative disorders part II: strategies for therapeutics development

Introduction: The cellular prion protein (PrP^C), some of its derivatives (especially PrP N-terminal N1 peptide and shed PrP), and PrP^C-containing exosomes have strong neuroprotective activities, which have been reviewed in the companion article (Part I) and are briefly summarized here.Areas covered: We propose that elevating the extracellular levels of a protective PrP form using gene therapy and other approaches is a very promising novel avenue for prophylactic and therapeutic treatments against prion disease, Alzheimer's disease, and several other neurodegenerative diseases. We will dissect the pros and cons of various potential PrP-based treatment options and propose a few strategies that are more likely to succeed. The cited references were obtained from extensive PubMed searches of recent literature, including peer-reviewed original articles and review articles.Expert opinion: Concurrent knockdown of celllular PrP expression and elevation of the extracellular levels of a neuroprotective PrP N-terminal peptide via optimized gene therapy vectors is a highly promising broad-spectrum prophylactic and therapeutic strategy against several neurodegenerative diseases, including prion diseases, Alzheimer's disease and Parkinson's disease.

Multi-Antigen Imaging Reveals Inflammatory DC, ADAM17 and Neprilysin as Effectors in Keloid Formation

Keloid is an aberrant scarring process of the skin, characterized by excessive extracellular matrix synthesis and deposition. The pathogenesis of this prevalent cutaneous disorder is not fully understood; however, a persistent inflammatory process is observed. To obtain more insight into this process, we analyzed lesional, perilesional and healthy tissue using multi-antigen-analysis (MAA) in conjunction with a data mining approach. Here, we demonstrate that monocyte-derived inflammatory dendritic cells (CD1a+, CD11c+, CD14+) and activated CD4+ T lymphocytes (CD45 RO+) dominated the immune infiltration in keloids while associating with fibroblasts. In perilesional tissue, precursor immune cells were dominant in the perivascular area, suggesting that they were attracted by an immune process, potentially in the lesional area. Supporting this hypothesis, only in keloid lesions, high levels of ADAM10/17 and Neprilysin (CD10) were observed in both fibroblasts and leukocytes. The spatial proximity of these two cell types, which could be confirmed by image analysis only in lesional tissue, could be a potential factor leading to the activation of fibroblasts. Our findings provide new insight into the pathogenesis of keloid formation and reveal metalloproteinases as a target for therapeutical intervention.

An Integrative Systems Biology Approach Identifies Molecular Signatures Associated with Gallbladder Cancer Pathogenesis

Gallbladder cancer (GBC) has a lower incidence rate among the population relative to other cancer types but is a major contributor to the total number of biliary tract system cancer cases. GBC is distinguished from other malignancies by its high mortality, marked geographical variation and poor prognosis. To date no systemic targeted therapy is available for GBC. The main objective of this study is to determine the molecular signatures correlated with GBC development using integrative systems level approaches. We performed analysis of publicly available transcriptomic data to identify differentially regulated genes and pathways. Differential co-expression network analysis and transcriptional regulatory network analysis was performed to identify hub genes and hub transcription factors (TFs) associated with GBC pathogenesis and progression. Subsequently, we assessed the epithelial-mesenchymal transition (EMT) status of the hub genes using a combination of three scoring methods. The identified hub genes including, CDC6, MAPK15, CCNB2, BIRC7, L3MBTL1 were found to be regulators of cell cycle components which suggested their potential role in GBC pathogenesis and progression.

Proteases Regulate Cancer Stem Cell Properties and Remodel Their Microenvironment

Proteolytic activity is perturbed in tumors and their microenvironment, and proteases also affect cancer stem cells (CSCs). CSCs are the therapy-resistant subpopulation of cancer cells with tumor-initiating capacity that reside in specialized tumor microenvironment niches. In this review, we briefly summarize the significance of proteases in regulating CSC activities with a focus on brain tumor glioblastoma. A plethora of proteases and their inhibitors participate in CSC invasiveness and affect intercellular interactions, enhancing CSC immune, irradiation, and chemotherapy resilience. Apart from their role in degrading the extracellular matrix enabling CSC migration in and out of their niches, we review the ability of proteases to modulate CSC properties, which prevents their elimination. When designing protease-oriented therapies, the multifaceted roles of proteases should be thoroughly investigated.

Reduced RECK levels accelerate skeletal muscle differentiation, improve muscle regeneration, and decrease fibrosis

The muscle regeneration process requires a properly assembled extracellular matrix (ECM). Its homeostasis depends on the activity of different matrix-metalloproteinases (MMPs). The reversion-inducing-cysteine-rich protein with kazal motifs (RECK) is a membrane-anchored protein that negatively regulates the activity of different MMPs. However, the role of RECK in the process of skeletal muscle differentiation, regeneration, and fibrosis has not been elucidated. Here, we show that during skeletal muscle differentiation of C2C12 myoblasts and in satellite cells on isolated muscle fibers, RECK is transiently up regulated. C2C12 myoblasts with reduced RECK levels are more prone to enter the differentiation program, showing an accelerated differentiation process. Notch-1 signaling was reduced, while p38 and AKT signaling were augmented in myoblasts with decreased RECK levels. Overexpression of RECK restores the normal differentiation process but diminished the ability to form myotubes. Transient up-regulation of RECK occurs during skeletal muscle regeneration, which was accelerated in RECK-deficient mice (Reck±). RECK, MMPs and ECM proteins augmented in chronically damaged WT muscle, a model of muscle fibrosis. In this model, RECK ± mice showed diminished fibrosis compared to WT. These results strongly suggest that RECK is acting as a potential myogenic repressor during muscle formation and regeneration, emerging as a new player in these processes, and as a potential target to treat individuals with the muscle-wasting disease.

CXCR6-CXCL16 Axis Promotes Breast Cancer by Inducing Oncogenic Signaling

Simple Summary

Breast cancer (BrCa) is the second leading cause of cancer-related deaths in American women, and its incidence is on the rise. Insufficient understanding of the mechanisms leading to BrCa limits the effectiveness of the treatment. In this article, we show the importance of a chemokine axis-CXCR6/CXCL16 in supporting BrCa progression. We have delineated BrCa-promoting mechanisms induced by this chemokine axis at the molecular level. This work projects the therapeutic significance of CXCR6/CXCL16 signaling for the treatment of BrCa.

Abstract

Precise mechanisms underlying breast cancer (BrCa) metastasis are undefined, which becomes a challenge for effective treatments. Chemokine signaling instigates the trafficking of cancer cells in addition to leukocytes. This study aimed to ascertain the clinical and biological significance of the CXCR6/CXCL16 signaling axis in the pathobiology of BrCa. Our data show a higher expression of CXCR6 in BrCa cell lines and tissues. Stage-III BrCa tissues express significantly higher CXCR6 compared to stage-II tissues. The ligand, CXCL16, could remain tethered to the cell surface, and, after proteolytic shedding of the ectodomain, the N-terminal fragment is released, converting it to its oncogenic, soluble form. Like CXCR6, N-terminal CXCL16 and ADAM-10 were significantly higher in stage-III than stage-II, but no significant difference was observed in the C-terminal fragment of CXCL16. Further, stimulation of the CXCR6/CXCL16 axis activated Src, FAK, ERK1/2, and PI3K signaling pathways, as per antibody microarray analysis, which also underlie CXCL16-induced F-actin polymerization. The CXCR6/CXCL16 axis induces cytoskeleton rearrangement facilitating migration and invasion and supports BrCa cell survival by activating the PI3K/Akt pathway. This study highlights the significance of the CXCR6/CXCL16 axis and ADAM10 as potential therapeutic targets for advanced-stage BrCa.

Methylation status of ADAM12 promoter are associated with its expression levels in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a kind of malignant tumor of digestive system severely affecting human health. The occurrence of CRC is a polygenic and multi-step complex process involving genetic and epigenetic alterations. ADAM12 (a disintegrin and metalloproteases 12), is a gene that was commonly hypermethylated in esophageal cancer using whole-genome methylation microarray in our previous study.

METHODS

We detected the methylation frequencies of the CpG island in ADAM12 promoter using bisulfite-pyrosequencing in CRC cell lines and tissue samples. The expression of ADAM12 was detected by quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC). A systematic and comprehensive analysis of relationship of DNA hypermethylation and ADAM12 expression in CRC was performed in our samples and TCGA database.

RESULTS

The expression of ADAM12 in hypermethylated cell lines was significantly lower than that in hypomethylated cell lines, and demethylation agent 5-Aza-dC could demethylate ADAM12 promoter region and reactivate ADAM12 expression effectively. In 74 pairs of colorectal cancer and normal tissues, bisulfite-pyrosequencing results showed significantly hypermethylation of ADAM12 in CRC compared with adjacent normal mucosa, accompanied with lower expression of ADAM12 in CRC tissues compared to that of the normal tissues. In addition, there was a statistically significant negative correlation between ADAM12 protein expression and methylation levels (rho =-0.28, p = 0.015).

CONCLUSION

Promoter hypermethylation was probably a mechanism of ADAM12 epigenetic silencing in CRC.

ADAM and ADAMTS Proteins, New Players in the Regulation of Hepatocellular Carcinoma Microenvironment

Simple Summary

Members of the adamalysin family are multi-domain proteins involved in many cancer-related functions. In this review, we will examine the literature on the involvement of adamalysins in hepatocellular carcinoma progression and their importance in the tumor microenvironment where they regulate the inflammatory response and the epithelial–mesenchymal transition. We complete this review with an analysis of adamalysin expression in a large cohort of patients with hepatocellular carcinoma from The Cancer Genome Atlas (TCGA) database. These original results give a new insight into the involvement of all adamalysins in the primary liver cancer.

Abstract

The tumor microenvironment plays a major role in tumor growth, invasion and resistance to chemotherapy, however understanding how all actors from microenvironment interact together remains a complex issue. The tumor microenvironment is classically represented as three closely connected components including the stromal cells such as immune cells, fibroblasts, adipocytes and endothelial cells, the extracellular matrix (ECM) and the cytokine/growth factors. Within this space, proteins of the adamalysin family (ADAM for a disintegrin and metalloproteinase; ADAMTS for ADAM with thrombospondin motifs; ADAMTSL for ADAMTS-like) play critical roles by modulating cell–cell and cell–ECM communication. During last decade, the implication of adamalysins in the development of hepatocellular carcinoma (HCC) has been supported by numerous studies however the functional characterization of most of them remain unsettled. In the present review we propose both an overview of the literature and a meta-analysis of adamalysins expression in HCC using data generated by The Cancer Genome Atlas (TCGA) Research Network.

Mechanistic insights of snake venom disintegrins in cancer treatment

Snake venoms are a potential source of various enzymatic and non-enzymatic compounds with a defensive role for the host. Various peptides with significant medicinal properties have been isolated and characterized from these venoms. Few of these are FDA approved. They inhibit tumor cells adhesion, migration, angiogenesis and metastasis by inhibiting integrins on transmembrane cellular surfaces. This plays important role in delaying tumor growth, neovascularization and development. Tumor targeting and smaller size make them ideal candidates as novel therapeutic agents for cancer treatment. This review is based on sources of these disintegrins, their targeting modality, classification and underlying anti-cancer potential.

The Tumor Proteolytic Landscape: A Challenging Frontier in Cancer Diagnosis and Therapy

In recent decades, dysregulation of proteases and atypical proteolysis have become increasingly recognized as important hallmarks of cancer, driving community-wide efforts to explore the proteolytic landscape of oncologic disease. With more than 100 proteases currently associated with different aspects of cancer development and progression, there is a clear impetus to harness their potential in the context of oncology. Advances in the protease field have yielded technologies enabling sensitive protease detection in various settings, paving the way towards diagnostic profiling of disease-related protease activity patterns. Methods including activity-based probes and substrates, antibodies, and various nanosystems that generate reporter signals, i.e., for PET or MRI, after interaction with the target protease have shown potential for clinical translation. Nevertheless, these technologies are costly, not easily multiplexed, and require advanced imaging technologies. While the current clinical applications of protease-responsive technologies in oncologic settings are still limited, emerging technologies and protease sensors are poised to enable comprehensive exploration of the tumor proteolytic landscape as a diagnostic and therapeutic frontier. This review aims to give an overview of the most relevant classes of proteases as indicators for tumor diagnosis, current approaches to detect and monitor their activity in vivo, and associated therapeutic applications.

Analysis of ADAM12-Mediated Ephrin-A1 Cleavage and Its Biological Functions

Accumulating evidence indicates that an elevated ephrin-A1 expression is positively correlated with a worse prognosis in some cancers such as colon and liver cancer. The detailed mechanism of an elevated ephrin-A1 expression in a worse prognosis still remains to be fully elucidated. We previously reported that ADAM12-cleaved ephrin-A1 enhanced lung vascular permeability and thereby induced lung metastasis. However, it is still unclear whether or not cleaved forms of ephrin-A1 are derived from primary tumors and have biological activities. We identified the ADAM12-mediated cleavage site of ephrin-A1 by a Matrix-assisted laser desorption ionization mass spectrometry and checked levels of ephrin-A1 in the serum and the urine derived from the primary tumors by using a mouse model. We found elevated levels of tumor-derived ephrin-A1 in the serum and the urine in the tumor-bearing mice. Moreover, inhibition of ADAM-mediated cleavage of ephrin-A1 or antagonization of the EphA receptors resulted in a significant reduction of lung metastasis. The results suggest that tumor-derived ephrin-A1 is not only a potential biomarker to predict lung metastasis from the primary tumor highly expressing ephrin-A1 but also a therapeutic target of lung metastasis.

Transmembrane protein ADAM29 facilitates cell proliferation, invasion and migration in clear cell renal cell carcinoma

Abnormal expression of ADAM29 has been frequently reported in several cancers, however, its role in clear cell renal cell carcinoma (ccRCC) has not evaluated in detail. Herein, we attempt to determine the biological role and the action mechanism of ADAM29 in ccRCC. Bioinformatics analysis based on the ccRCC RNA-Seq dataset from TCGA database revealed that ADAM29 was up-expressed in ccRCC tissues by comparison with normal tissues. And a significant increase of ADAM29 expression was also observed in 3 ccRCC cell lines (UT33A, Caki-1, and786-O) in comparison with normal cell line. Besides, high level of ADAM29 was found to be connected with the poor prognosis and could be considered as an independent prognosticator for patients with ccRCC. Furthermore, functional experiments in vitro demonstrated that ADAM29 promoted the growth, invasion and migration of ccRCC cells. Moreover, Western blot assays indicated that ADAM29 was positively correlated with the level of proliferation-related proteins Cyclin D1 and PCNA and motion-related proteins MMP9 and Snail. Our data indicate that ADAM29 acts as an oncogene that increases tumour cells proliferation, invasion and migration partly by regulating the expression of Cyclin D1/PCNA/MMP9/Snail, suggesting that ADAM29 may become a prognosticator and therapeutic candidate for ccRCC.

An Overview of ADAM9: Structure, Activation, and Regulation in Human Diseases

ADAM9 (A disintegrin and a metalloprotease 9) is a membrane-anchored protein that participates in a variety of physiological functions, primarily through the disintegrin domain for adhesion and the metalloprotease domain for ectodomain shedding of a wide variety of cell surface proteins. ADAM9 influences the developmental process, inflammation, and degenerative diseases. Recently, increasing evidence has shown that ADAM9 plays an important role in tumor biology. Overexpression of ADAM9 has been found in several cancer types and is correlated with tumor aggressiveness and poor prognosis. In addition, through either proteolytic or non-proteolytic pathways, ADAM9 promotes tumor progression, therapeutic resistance, and metastasis of cancers. Therefore, comprehensively understanding the mechanism of ADAM9 is crucial for the development of therapeutic anti-cancer strategies. In this review, we summarize the current understanding of ADAM9 in biological function, pathophysiological diseases, and various cancers. Recent advances in therapeutic strategies using ADAM9-related pathways are presented as well.

The Role of Extracellular Proteases in Tumor Progression and the Development of Innovative Metal Ion Chelators that Inhibit their Activity

The crucial role of extracellular proteases in cancer progression is well-known, especially in relation to the promotion of cell invasion through extracellular matrix remodeling. This also occurs by the ability of extracellular proteases to induce the shedding of transmembrane proteins at the plasma membrane surface or within extracellular vesicles. This process results in the regulation of key signaling pathways by the modulation of kinases, e.g., the epidermal growth factor receptor (EGFR). Considering their regulatory roles in cancer, therapeutics targeting various extracellular proteases have been discovered. These include the metal-binding agents di-2-pyridylketone 4,4-dimethyl-3-thiosemicarbazone (Dp44mT) and di-2-pyridylketone-4-cyclohexyl-4-methyl-3-thiosemicarbazone (DpC), which increase c-MET degradation by multiple mechanisms. Both the direct and indirect inhibition of protease expression and activity can be achieved through metal ion depletion. Considering direct mechanisms, chelators can bind zinc(II) that plays a catalytic role in enzyme activity. In terms of indirect mechanisms, Dp44mT and DpC potently suppress the expression of the kallikrein-related peptidase-a prostate-specific antigen-in prostate cancer cells. The mechanism of this activity involves promotion of the degradation of the androgen receptor. Additional suppressive mechanisms of Dp44mT and DpC on matrix metalloproteases (MMPs) relate to their ability to up-regulate the metastasis suppressors N-myc downstream regulated gene-1 (NDRG1) and NDRG2, which down-regulate MMPs that are crucial for cancer cell invasion.

ADAM28: Another ambivalent protease in cancer

Emergence of novel therapeutic options in a perspective of personalized therapy of cancer relies on the discovery of precise molecular mechanisms involved in the switch from a localized tumor to invasive metastasis spread. Pro-tumor functions have been mostly ascribed to proteolytic enzymes from the metalloproteinase family including A Disintegrin And Metalloproteinases (ADAMs). Particularly, when expressed by cancer cells, ADAM28 protease supports cancer cell proliferation, survival and migration as well as metastatic progression. In sharp contrast, ADAM28 derived from the tumor microenvironment has shown to exert strong protective effects against deleterious metastasis dissemination. Indeed, depletion of host-derived ADAM28 (ADAM28 KO mice) accelerates colonization lung tissues, increases tumor foci implantation, and impairs T cell immune response. In this review, we outline specific ADAM28 functions when specifically expressed by carcinoma cells or by tumor microenvironment. Finally, we discuss about future research strategies that could be pursued to highlight new functions of this protease in cancer.

LncRNA LINC00689 Promotes the Progression of Gastric Cancer Through Upregulation of ADAM9 by Sponging miR-526b-3p

Introduction

Increasing studies have demonstrated that noncoding RNAs, including miRNAs and lncRNAs, have vital roles in mediating cancer progression. However, the expression features and biological functions of LINC00689 in gastric cancer (GC) remain largely unknown. This study was designed to investigate the functions of LINC00689, miR-526b-3p and ADAM9 as well as their interactions in GC.

Methods

Real time PCR(RT-PCR) was used to detect the expression of LINC0068, miR-526b-3p and ADAM9 in both GC tissues or cell lines. Gain- and loss- of functions of assays were conducted to verify the role of LINC0068, miR-526b-3p and ADAM9 in GC development. Cell proliferation were determined by CCK8 assay and transwell assay and scratch wound-healing assay were used to test cell invasion and migration. Further, the relationships between LINC00689 and miR-526b-3p, miR-526b-3p and ADAM9 were predicted by bioinformatics analysis and then proved by Luciferase reporter assay and RNA Immunoprecipitation(RIP) assay.

Results

We found that LINC00689 was upregulated in GC tissues and positively correlated with advanced tumor stage and tumor size, while miR-526b-3p was downregulated. Furthermore, gain- and loss-of-function experiments revealed that LINC00689 promoted the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of GC cells, while miR-526b-3p had the opposite effects. The underlying mechanisms indicated that LINC00689 functioned as a competing endogenous RNA (ceRNA) by sponging miR-526b-3p in GC cells. Further investigations confirmed that ADAM9 was a direct target of miR-526b-3p and positively modulated the progression of GC.

Conclusion

Our study suggests that LINC00689 functions as a novel oncogenic lncRNA in the development of GC by promoting ADAM9 expression through suppression of miR-526b-3p.

Combination of pembrolizumab and 125I attenuates the aggressiveness of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-associated mortality. Therapies targeting programmed cell death 1 ligand 1 (PD1L1) have promising effects on NSCLC. However, resistance to targeted therapy has become the main problem and the underling molecular mechanism remains unclear. In the present study, the expression of PD1L1 in NSCLC was determined and the association with clinicopathological characteristics was analyzed. A combination therapy was also constructed, including pembrolizumab (Pem) and iodine-125 (¹²⁵I), which represented an efficient strategy for the treatment of NSCLC. The expression of PD1L1 was upregulated in NSCLC tissues and positively correlated with the Ki-67 index, pathological subtypes and risk stages. A higher level of PD1L1 expression was associated with poorer survival in patients with NSCLC, which could be used as a prognostic indicator. When NSCLC cells were cultured in the presence of Pem and ¹²⁵I seeds, the combination treatment significantly abrogated the tumor proliferation and aggressiveness through the inhibition of matrix metalloproteinase-2 and -9 secretion. Flow cytometry analysis revealed pembrolizumab combined with ¹²⁵I contributed to a higher rate of apoptosis and cell cycle arrest, indicating that the combination treatment improved the resistance to immunotherapy. Furthermore, the associated molecular mechanism was the dysregulation of ADAM metallopeptidase domain 17. The findings from the present study revealed that PD1L1 could be used as a predictive biomarker, and the application of combination treatment of pembrolizumab and ¹²⁵I showed promising effects on NSCLC.