Role of trypsin and protease-activated receptor-2 in ovarian cancer

Novel poly-deep eutectic solvent-functionalized magnetic graphene oxide nanomaterials for high-performance solid-phase extraction of trypsin

Three novel polymethacrylic acid-based deep eutectic solvent (DES)-functionalized magnetic graphene oxide composites were designed and successfully synthesized via the radical polymerization method. The aim was to achieve the selective solid-phase extraction of trypsin (Tryp). Among them, the magnetic extractant (MGO@PDES2) functionalized with a poly-deep eutectic solvent composed of tetraethylammonium chloride and methylpropionic acid at a molar ratio of 1 : 2 exhibited the highest extraction efficiency for Tryp. Owing to the high specific surface area of MGO and the abundant carboxyl functional groups in PDES2, the prepared MGO@PDES2 exhibited excellent selectivity and stability for Tryp extraction. Under optimal conditions, the extraction capacity of Tryp by MGO@PDES2 reached 708.85 mg g-1. The extraction driving forces between MGO@PDES2 and Tryp were hydrogen-bonding interactions and electrostatic interactions. Among the seven biomacromolecules, MGO@PDES2 displayed outstanding selectivity for Tryp. In addition, the results of cycling experiments indicated that MGO@PDES2 could be reused many times without a significant change in extraction capacity. Moreover, the proposed method was successfully applied to extract Tryp from the crude extract of bovine pancreas, yielding satisfactory results. All the results suggest that MGO@PDES2 is a promising magnetic extractant, which is expected to provide new ideas for the extraction and separation of proteins.

The application of snake venom in anticancer drug discovery: an overview of the latest developments

INTRODUCTION

Snake venom is a rich source of toxins with great potential for therapeutic applications. In addition to its efficacy in treating hypertension, acute coronary syndrome, and other heart conditions, research has shown that this potent enzymatic cocktail is capable of selectively targeting and destroying cancer cells in many cases while sparing healthy cells.

AREAS COVERED

The authors begin by acknowledging the emerging trends in snake-derived targeted therapies in battling cancer. An extensive literature review examining the effects of various snake venom toxins on cancer cell lines, highlighting the specific cancer hallmarks each toxin targets is presented. Furthermore, the authors emphasize the emerging potential of artificial intelligence in accelerating snake venom-based drug discovery for cancer treatment, showcasing several innovative software applications in this field.

EXPERT OPINION

Research on snake venom toxins indicates promising potential for cancer treatment as many of the discussed toxins can specifically target cancer cells. Nevertheless, variations in the composition of venoms, ethical issues, and delivery barriers limit their development into effective therapies. Thus, advances in biotechnology, molecular engineering, in silico methods are crucial for the refinement of venom-derived compounds, improving their specificity, and overcoming these challenges, ultimately enhancing their therapeutic potential in cancer therapy.

Non-classical neutrophil extracellular traps induced by PAR2-signaling proteases

Neutrophil extracellular traps (NETs) are associated with diseases linked to aberrant coagulation. The blood clotting cascade involves a series of proteases, some of which induce NET formation via a yet unknown mechanism. We hypothesized that this formation involves signaling via a factor Xa (FXa) activation of the protease-activated receptor 2 (PAR2). Our findings revealed that NETs can be triggered in vitro by enzymatically active proteases and PAR2 agonists. Intravital microscopy of the liver vasculature revealed that both FXa infusion and activation of endogenous FX promoted NET formation, effects that were prevented by the FXa inhibitor, apixaban. Unlike classical NETs, these protease-induced NETs lacked bactericidal activity and their proteomic signature indicates their role in inflammatory disorders, including autoimmune diseases and carcinogenesis. Our findings suggest a novel mechanism of NET formation under aseptic conditions, potentially contributing to a self-amplifying clotting and NET formation cycle. This mechanism may underlie the pathogenesis of disseminated intravascular coagulation and other aseptic conditions.

Bioinformatics and experimental insights into F2RL1 as a key biomarker in cervical cancer diagnosis and prognosis

Cervical cancer(CCa) remains a significant global public health concern, with early diagnosis and treatment being crucial. Moreover, the molecular mechanisms underlying its pathogenesis remain incompletely elucidated. F2RL1 is closely associated with various tumors. However, its relationship with CCa is poorly understood. We accessed data from 309 patients diagnosed with CCa from TCGA database. The Limma package facilitated differential expression analysis to identify differentially expressed mRNAs (DEmRNAs). Survival analysis and ROC analysis were conducted via the XIANTAO database. Immune-related genes were identified with F2RL1-related genes through ImmPort database analysis. Functional enrichment analysis was carried out using GO, KEGG, and GSEA. We gathered cervical cells and serum from participants to test for HPV and TCT, and then used qPCR to check the levels of F2RL1 mRNA expression. We also verified the expression of F2RL1 protein through WB and ELISA techniques. Our investigation has unveiled a fascinating discovery-the levels of F2RL1 expression in CCa tissues are notably elevated when compared to normal tissues, showcasing intriguing variations among various pathological types. Moreover, the presence of high F2RL1 expression is linked to reduce Overall Survival (OS), Progression Free Interval (PFI), Progression Free Survival (PFS). F2RL1 rocked the ROC analysis with an AUC of 0.996. Furthermore, F2RL1 expression levels significantly impact CCa in different N stages, pathological tissue types, treatment statuses, and racial groups, allowing us to develop a predictive model. Additionally, we identified 43 immune-related genes. Enrichment analysis highlighting their association with pathways related to cell movement and T cell activation. Through analysis, we discovered an inverse proportion between F2RL1 expression and the infiltration of most immune cells, particularly TFH and cytotoxic cells, suggesting a potential link to immune evasion in CCa. Molecular biology experiments also confirmed a significant increase in F2RL1 expression in cervical exfoliated cells and serum. Our research uncovers the predictive and early detection significance of F2RL1 in CCa and its correlation with immune infiltration for the first time. F2RL1 is strongly linked to the progression of CCa and could serve as a biomarker for the early diagnosis and prognosis of CCa patients.

The NF-κB-HE4 axis: A novel regulator of HE4 secretion in ovarian cancer

Ovarian cancer is the leading cause of death among gynecologic malignancies. Despite recent advancements in targeted therapies such as PARP inhibitors, recurrence is common and frequently resistant to existing therapies. A powerful diagnostic tool, coupled with a comprehensive understanding of its implications, is crucial. HE4, a clinical serum biomarker for ovarian cancer, has shown efficacy in monitoring malignant phenotypes, yet little is known about its biological role and regulatory mechanisms. Our research demonstrates that HE4 expression in ovarian cancer can be regulated by the NF-κB signaling pathway. We found that the activation of NF-κB signaling by tumor necrosis factor (TNF)-α, a cytokine found in ovarian cancer tumors and ascites, enhanced the secretion of HE4 while its inhibition suppressed HE4 levels. Nuclear translocation of the NF-κB component p65 was found to be critical for HE4 expression; induced NF-κB activation through p65 expression or constitutive IKK2 activity elevated HE4 expression, while p65 knockdown had the opposite effect. Furthermore, we observed that NF-κB mediated HE4 expression at the transcriptional level. Our data also suggests that there is a regulatory role for HE4 in the expression of α5-Integrin, a crucial adhesion molecule in ovarian cancer metastasis; HE4 knockdown corresponded with reduced α5-Integrin expression, cell migration and cell adhesion to fibronectin.

Enzymatic response of heparin-protamine complex: Spectroscopic investigation and application for lung adenocarcinoma cells detection

Though the heparin-protamine complex (HP complex) is a crucial system utilized in clinical settings, the metabolic pathways of this complex remain inadequately understood. Herein, the enzymatic degradation of the heparin-protamine complex by trypsin and its broader implications were investigated. By utilizing fluorescent gold nanoclusters liganded with the HP complex (AuNCs-HP complex), we observed significant morphological and spectral changes during enzymatic degradation. Experiments showed that AuNCs-HP complex could be degraded and cleaved into small fragments by trypsin. Moreover, the AuNCs-HP complex demonstrated its potential as a highly sensitive spectral sensing platform, enabling precise measurement of trypsin activity with an outstanding detection limit (0.34 ng mL-1). Additionally, we explored its utility for specific tumor cell detection, focusing on lung adenocarcinoma cells, and successfully identified their presence through distinctive fluorescence changes. These remarkable findings not only contribute valuable insights into targeted degradation systems but also offer promising opportunities for cancer biomarker detection. The AuNCs-HP complex serves as an innovative tool for real-time trypsin activity monitoring, paving the way for advanced biomedical applications.

New Target(s) for RNF43 Regulation: Implications for Therapeutic Strategies

Cancer cells depend on specific oncogenic pathways or present a genetic alteration that leads to a particular disturbance. Still, personalized and targeted biological therapy remains challenging, with current efforts generally yielding disappointing results. Carefully assessing onco-target molecular pathways can, however, potently assist with such efforts for the selection of patient populations that would best respond to a given drug treatment. RNF43, an E3 ubiquitin ligase that negatively regulates Wnt/frizzled (FZD) receptors by their ubiquitination, internalization, and degradation, controls a key pathway in cancer. Recently, additional target proteins of RNF43 were described, including p85 of the PI3K/AKT/mTOR signaling pathway and protease-activated receptor 2 (PAR2), a G-protein-coupled receptor that potently induces β-catenin stabilization, independent of Wnts. RNF43 mutations with impaired E3 ligase activity were found in several types of cancers (e.g., gastrointestinal system tumors and endometrial and ovarian cancer), pointing to a high dependency on FZD receptors and possibly PAR2 and the PI3K/AKT/mTOR signaling pathway. The development of drugs toward these targets is essential for improved treatment of cancer patients.

Recessively Inherited Deficiency of Secreted WFDC2 (HE4) Causes Nasal Polyposis and Bronchiectasis

Rationale: Bronchiectasis is a pathological dilatation of the bronchi in the respiratory airways associated with environmental or genetic causes (e.g., cystic fibrosis, primary ciliary dyskinesia, and primary immunodeficiency disorders), but most cases remain idiopathic. Objectives: To identify novel genetic defects in unsolved cases of bronchiectasis presenting with severe rhinosinusitis, nasal polyposis, and pulmonary Pseudomonas aeruginosa infection. Methods: DNA was analyzed by next-generation or targeted Sanger sequencing. RNA was analyzed by quantitative PCR and single-cell RNA sequencing. Patient-derived cells, cell cultures, and secretions (mucus, saliva, seminal fluid) were analyzed by Western blotting and immunofluorescence microscopy, and mucociliary activity was measured. Blood serum was analyzed by electrochemiluminescence immunoassay. Protein structure and proteomic analyses were used to assess the impact of a disease-causing founder variant. Measurements and Main Results: We identified biallelic pathogenic variants in WAP four-disulfide core domain 2 (WFDC2) in 11 individuals from 10 unrelated families originating from the United States, Europe, Asia, and Africa. Expression of WFDC2 was detected predominantly in secretory cells of control airway epithelium and also in submucosal glands. We demonstrate that WFDC2 is below the limit of detection in blood serum and hardly detectable in samples of saliva, seminal fluid, and airway surface liquid from WFDC2-deficient individuals. Computer simulations and deglycosylation assays indicate that the disease-causing founder variant p.Cys49Arg structurally hampers glycosylation and, thus, secretion of mature WFDC2. Conclusions: WFDC2 dysfunction defines a novel molecular etiology of bronchiectasis characterized by the deficiency of a secreted component of the airways. A commercially available blood test combined with genetic testing allows its diagnosis.

Involvement of Protease-Activated Receptor2 Pleckstrin Homology Binding Domain in Ovarian Cancer: Expression in Fallopian Tubes and Drug Design

Studying primordial events in cancer is pivotal for identifying predictive molecular indicators and for targeted intervention. While the involvement of G-protein-coupled receptors (GPCRs) in cancer is growing, GPCR-based therapies are yet rare. Here, we demonstrate the overexpression of protease-activated receptor 2 (PAR2), a GPCR member in the fallopian tubes (FTs) of high-risk BRCA carriers as compared to null in healthy tissues of FT. FTs, the origin of ovarian cancer, are known to express genes of serous tubal intraepithelial carcinoma (STICs), a precursor lesion of high-grade serous carcinoma (HGSC). PAR2 expression in FTs may serve as an early prediction sensor for ovarian cancer. We show now that knocking down Par2 inhibits ovarian cancer peritoneal dissemination in vivo, pointing to the central role of PAR2. Previously we identified pleckstrin homology (PH) binding domains within PAR1,2&4 as critical sites for cancer-growth. These motifs associate with PH-signal proteins via launching a discrete signaling network in cancer. Subsequently, we selected a compound from a library of backbone cyclic peptides generated toward the PAR PH binding motif, namely the lead compound, Pc(4-4). Pc(4-4) binds to the PAR PH binding domain and blocks the association of PH-signal proteins, such as Akt or Etk/Bmx with PAR2. It attenuates PAR2 oncogenic activity. The potent inhibitory function of Pc(4-4) is demonstrated via inhibition of ovarian cancer peritoneal spread in mice. While the detection of PAR2 may serve as a predictor for ovarian cancer, the novel Pc(4-4) compound may serve as a powerful medicament in STICs and ovarian cancer. This is the first demonstration of the involvement of PAR PH binding motif signaling in ovarian cancer and Pc(4-4) as a potential therapy treatment.

Serum tumor markers for response prediction and monitoring of advanced lung cancer: A review focusing on immunotherapy and targeted therapies

BACKGROUND

The value of serum tumor markers (STMs) in the current therapeutic landscape of lung cancer is unclear.

OBJECTIVE

This scoping review gathered evidence of the predictive, prognostic, and monitoring value of STMs for patients with advanced lung cancer receiving immunotherapy (IT) or targeted therapy (TT).

METHODS

Literature searches were conducted (cut-off: May 2022) using PubMed and Cochrane CENTRAL databases. Medical professionals advised on the search strategies.

RESULTS

Study heterogeneity limited the evidence and inferences from the 36 publications reviewed. While increased baseline levels of serum cytokeratin 19 fragment antigen (CYFRA21-1) and carcinoembryonic antigen (CEA) may predict IT response, results for TT were less clear. For monitoring IT-treated patients, STM panels (including CYFRA21-1, CEA, and neuron-specific enolase) may surpass the power of single analyses to predict non-response. CYFRA21-1 measurement could aid in monitoring TT-treated patients, but the value of CEA in this context requires further investigation. Overall, baseline and dynamic changes in individual or combined STM levels have potential utility to predict treatment outcome and for monitoring of patients with advanced lung cancer.

CONCLUSIONS

In advanced lung cancer, STMs provide additional relevant clinical information by predicting treatment outcome, but further standardization and validation is warranted.

Advances in screening, synthesis, modification, and biomedical applications of peptides and peptide aptamers

Peptides and peptide aptamers have emerged as promising molecules for a wide range of biomedical applications due to their unique properties and versatile functionalities. The screening strategies for identifying peptides and peptide aptamers with desired properties are discussed, including high-throughput screening, display screening technology, and in silico design approaches. The synthesis methods for the efficient production of peptides and peptide aptamers, such as solid-phase peptide synthesis and biosynthesis technology, are described, along with their advantages and limitations. Moreover, various modification techniques are explored to enhance the stability, specificity, and pharmacokinetic properties of peptides and peptide aptamers. This includes chemical modifications, enzymatic modifications, biomodifications, genetic engineering modifications, and physical modifications. Furthermore, the review highlights the diverse biomedical applications of peptides and peptide aptamers, including targeted drug delivery, diagnostics, and therapeutic. This review provides valuable insights into the advancements in screening, synthesis, modification, and biomedical applications of peptides and peptide aptamers. A comprehensive understanding of these aspects will aid researchers in the development of novel peptide-based therapeutics and diagnostic tools for various biomedical challenges.

Protease-activated receptor 2 attenuates doxorubicin-induced apoptosis in colon cancer cells

Drug resistance represents a major problem in cancer treatment. Doxorubicin (adriamycin) is an injectable DNA intercalating drug that halts cancer cell growth by inhibiting topoisomerase 2, but its long-term effectiveness is compromised by onset of resistance. This study demonstrates that expression of the PAR2 gene in human colon adenocarcinoma tissue samples was the highest among 32 different cancer types (n = 10,989), and higher in colon adenocarcinoma tissues (n = 331) than normal colon tissues (n = 308), revealing an association between PAR2 expression and human colon cancer. HT29 cells are a human colorectal adenocarcinoma cell line that is sensitive to the chemotherapeutic drug doxorubicin and also expresses PAR2. We find that PAR2 activation in HT29 cells, either by an endogenous protease agonist (trypsin) or an exogenous peptide agonist (2f-LIGRL-NH2), significantly reduces doxorubicin-induced cell death, reactive oxygen species production, caspase 3/7 activity and cleavage of caspase-8 and caspase-3. Moreover, PAR2-mediated MEK1/2-ERK1/2 pathway induced by 2f-LIGRL-NH2 leads to upregulated anti-apoptotic MCL-1 and Bcl-xL proteins that promote cellular survival. These findings suggest that activation of PAR2 compromises efficacy of doxorubicin in colon cancer. Further support for this conclusion came from experiments with human colon cancer HT29 cells, either with the PAR2 gene deleted or in the presence of a pharmacological antagonist of PAR2, which showed full restoration of all doxorubicin-mediated effects. Together, these findings reveal a strong link between PAR2 activation and signalling in human colon cancer cells and increased survival against doxorubicin-induced cell death. They support PAR2 antagonism as a possible new strategy for enhancing doxorubicin therapy.

Evaluation of He4 Use in the Diagnosis of Ovarian Cancer: First and Second Recurrence, and an Analysis of HE4 Concentration during Second- and Third-Line Chemotherapy

HE4 is a commonly used tumor marker for ovarian cancer (OC) diagnosis. In our study, we aimed to assess its use in the diagnosis of subsequent OC recurrences and to evaluate its changes during recurrence diagnosis and the subsequent lines of chemotherapy treatment. This retrospective single center study was conducted on 188 patients treated for ovarian cancer recurrence at the Department of Gynecological Surgery and Gynecological Oncology. The sensitivity and specificity of HE4 for patient survival prediction were analyzed using Receiver Operating Characteristics (ROC) and area under the curve (AUC) with 95% confidence intervals (95% CI). Survival times to reach one of the endpoints (OS, PFS, TFI, PFS2, TFI2) were analyzed using Kaplan-Meier curves. Elevated HE4 levels at the time of first relapse diagnosis, and after the third and the last course of second-line chemotherapy, significantly influences the time from OC diagnosis until first disease recurrence (PFS2) (p = 0.005, p = 0.015 and p = 0.002, respectively). Additionally, elevated serum HE4 concentration at the time of OC diagnosis (p = 0.012), and its later recurrence (first (p < 0.001), and second recurrent diagnosis (p = 0.143)) significantly influences patient OS. Increased HE4 concentration at the end of chemotherapeutic treatment negatively affects overall patient survival ((p = 0.006 for second line chemotherapy and (p = 0.022) for elevated HE4 concentration after the last course of third-line chemotherapy). Our preliminary results show an encouraging diagnostic and prognostic role of HE4 in recurrent ovarian cancer. HE4 measurements at different treatment time points during the second- and third-line chemotherapy treatment seem to correlate with patient survival.

Elevated expression of the membrane-anchored serine protease TMPRSS11E in NSCLC progression

TMPRSS11E was found to be upregulated in human nonsmall cell lung cancer samples (NSCLC) and cell lines, and high expression was associated with poor survival of NSCLC patients. The results of in vitro and in vivo experiments showed that overexpressing TMPRSS11E resulted in A549 cell proliferation and migration promotion, while the TMPRSS11E S372A mutant with the mutated catalytic domain lost the promoting function. In addition, in mouse xenograft models, silencing TMPRSS11E expression inhibited the growth of 95D cell-derived tumors. To explore the mechanism of marked upregulation of TMPRSS11E in NSCLC cells, promoter analysis, EMSA, and ChIP assays were performed. STAT3 was identified as the transcription factor responsible for TMPRSS11E transcription. Moreover, the purified recombinant TMPRSS11E catalytic domain exhibited enzymatic activity for the proteolytic cleavage of PAR2. Recombinant TMPRSS11E catalytic domain incubation further activated the PAR2-EGFR-STAT3 pathway. These findings established a mechanism of TMPRSS11E-PAR2-EGFR-STAT3 positive feedback, and the oncogenic role of TMPRSS11E as a PAR2 modulator in NSCLC was revealed.

A Label-Free Fluorescence Aptasensor Based on G-Quadruplex/Thioflavin T Complex for the Detection of Trypsin

A novel, label-free fluorescent assay has been developed for the detection of trypsin by using thioflavin T as a fluorescent probe. A specific DNA aptamer can be combined by adding cytochrome c. Trypsin hydrolyzes the cytochrome c into small peptide fragments, exposing the G-quadruplex part of DNA aptamer, which has a high affinity for thioflavin T, which then enhances the fluorescence intensity. In the absence of trypsin, the fluorescence intensity was inhibited as the combination of cytochrome c and the DNA aptamer impeded thioflavin T’s binding. Thus, the fluorescent biosensor showed a linear relationship from 0.2 to 60 μg/mL with a detection limit of 0.2 μg/mL. Furthermore, the proposed method was also successfully employed for determining trypsin in biological samples. This method is simple, rapid, cheap, and selective and possesses great potential for the detection of trypsin in bioanalytical and biological samples and medical diagnoses.

The Proteolytic Landscape of Ovarian Cancer: Applications in Nanomedicine

Ovarian cancer (OvCa) is one of the leading causes of mortality globally with an overall 5-year survival of 47%. The predominant subtype of OvCa is epithelial carcinoma, which can be highly aggressive. This review launches with a summary of the clinical features of OvCa, including staging and current techniques for diagnosis and therapy. Further, the important role of proteases in OvCa progression and dissemination is described. Proteases contribute to tumor angiogenesis, remodeling of extracellular matrix, migration and invasion, major processes in OvCa pathology. Multiple proteases, such as metalloproteinases, trypsin, cathepsin and others, are overexpressed in the tumor tissue. Presence of these catabolic enzymes in OvCa tissue can be exploited for improving early diagnosis and therapeutic options in advanced cases. Nanomedicine, being on the interface of molecular and cellular scales, can be designed to be activated by proteases in the OvCa microenvironment. Various types of protease-enabled nanomedicines are described and the studies that focus on their diagnostic, therapeutic and theranostic potential are reviewed.

Proteomic Profiles of Body Mass Index and Waist-to-Hip Ratio and Their Role in Incidence of Diabetes

CONTEXT

It is unclear to what extent the plasma proteome of abdominal fat distribution differs from that of body mass index, and whether the differences have clinical implications.

OBJECTIVE

To evaluate the difference between the plasma proteomic profiles of body mass index (BMI) and waist-to-hip ratio (WHR), and then examine the identified BMI- or WHR-specific proteins in relation to incidence of diabetes.

METHODS

Data were obtained from the Malmö Diet and Cancer-Cardiovascular Cohort study in the general community. Participants (n = 4203) with no previous diabetes (aged 57.2 ± 6.0 years, 37.8% men) were included. Plasma proteins (n = 136) were measured by the Proseek proximity extension method. BMI- and WHR-specific proteins were identified at baseline using a 2-step iterative resampling approach to optimize internal replicability followed by β coefficient comparisons. The identified proteins were considered internally replicated and were then studied in relation to incident diabetes by Cox proportional hazards regression analysis. The main outcome measure was incident diabetes over a mean follow-up of 20.3 ± 5.9 years.

RESULTS

After excluding 21 overlapping proteins and proteins that did not show significantly different associations with BMI vs WHR, 10 internally replicated proteins were found to be specific to BMI, and 22 were found to be specific to WHR (false discovery rate-adjusted P < .05). Of the WHR-specific proteins, 18 remained associated with diabetes risk after multivariate adjustments, whereas none of the BMI-specific proteins showed associations with diabetes risk.

CONCLUSION

Abdominal fat distribution was associated with some unique characteristics of the plasma proteome that potentially could be related to its additional risk of diabetes beyond general obesity.

Comparative study of the binding between chlorogenic acid and four proteins by isothermal titration calorimetry, spectroscopy and docking methods

As a polyphenolic compound, chlorogenic acid has antioxidant, anti-inflammatory, antiviral, anti-obesity and other effects. Based on the interactions between chlorogenic acid and the proteins (human serum albumin (HSA), pepsin (Pep), trypsin (Try), fat mass and obesity-associated protein (FTO)), results will provide clues for screening effective inhibitors. The interaction between chlorogenic acid and the four proteins (HSA, Pep, Try, FTO) was analyzed by the aid of fluorescence quenching, synchronous fluorescence, three-dimensional fluorescence, isothermal titration calorimetry, and molecular docking. It can be concluded that there is no obvious interaction between chlorogenic acid and FTO. The binding affinity between chlorogenic acid and three proteins is HSA > Try > Pep. The binding process is spontaneous, and the quenching type is static quenching. Hydrophobic interaction and hydrogen bonding is observed in the binding process. This study provides valuable information for understanding the interaction mechanism between chlorogenic acid and proteins, and provides clues for screening inhibitors.

Trypsin Depolarizes Pacemaker Potentials in Murine Small Intestinal Interstitial Cells of Cajal

Interstitial cells of Cajal (ICCs) generate pacemaker potentials in the gastrointestinal (GI) tract. In this study, the effects of trypsin on pacemaker potentials in murine small intestinal ICCs were examined. We used whole-cell patch-clamp analysis. The results of whole-cell patch-clamp analysis revealed that trypsin dose-dependently depolarized pacemaker potentials and decreased their amplitude. Treatments with the antagonists of neurokinin1 (NK1) and NK2 receptors (SR-140333 and SR-48968, respectively) slightly inhibited the trypsin-induced responses. However, treatment with the combination of SR-140333 and SR-48968 completely inhibited trypsin-induced responses. Trypsin slightly depolarized pacemaker potentials and increased their amplitude after the intracellular application of GDP-β-S. Additionally, incubation in external Ca2+-free solution inhibited trypsin-induced responses. In the presence of U-73122, staurosporine, Go6976, or xestospongin C, trypsin did not depolarize the pacemaker’s potentials. However, trypsin depolarized the pacemaker potentials in the presence of rottlerin. Finally, HC067047, a TRPV4 inhibitor, did not affect the trypsin-induced responses. These results suggest that trypsin depolarized pacemaker potentials through NK1 and NK2 receptors in the murine small intestinal ICCs, with this effect being dependent on the G protein, phospholipase C, protein kinase C, inositol triphosphate pathways, and extracellular Ca2+ but being independent of the TRPV4 pathway. Hence, trypsin-mediated GI motility regulation must be considered for prokinetic drug developments.

Heparin-enhanced peroxidase-like activity of iron-cobalt oxide nanosheets for sensitive colorimetric detection of trypsin

Iron-cobalt oxide nanosheets (FeCo-ONSs) were proved to have intrinsic peroxidase-like activity. Additionally, the peroxidase-like activity of FeCo-ONSs toward the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) was dramatically enhanced after heparin addition due to the stronger affinity toward TMB. Protamine combines with heparin, so the promotion of peroxidase-like activity of FeCo-ONSs with heparin was suppressed. With the addition of trypsin, protamine was hydrolyzed and the enhancement effect of catalytic activity of FeCo-ONSs was recovered. Based on above process, a sensitive colorimetric platform for trypsin activity determination was constructed through measuring the absorbance of produced oxTMB at 652 nm, providing a linear detection range of 5 to 500 ng/mL and a low detection limit of 2.8 ng/mL. The method was applied to trypsin determination in real samples (human urine sample and multienzyme tablet sample) with satisfactory results, illustrating the potential application of this biosensor.

Therapeutic potential of marine peptides in cervical and ovarian cancers

Cervical and ovarian cancers contribute significantly to female morbidity and mortality worldwide. The current standard of treatment, including surgical removal, radiation therapy, and chemotherapy, offers poor outcomes. There are many side effects to traditional chemotherapeutic agents and treatment-resistant types, and often the immune response is depressed. As a result, traditional approaches have evolved to include new alternative remedies, such as natural compounds. Aquatic species provide a rich supply of possible drugs. The potential anti-cancer peptides are less toxic to normal cells and can attenuate multiple drug resistance by providing an efficacious treatment approach. The physiological effects of marine peptides are described in this review focusing on various pathways, such as apoptosis, microtubule balance disturbances, suppression of angiogenesis, cell migration/invasion, and cell viability. The review also highlights the potential role of marine peptides as safe and efficacious therapeutic agent for the treatment of cervical and ovarian cancers.

Multimeric Association of Purified Novel Bowman-Birk Inhibitor From the Medicinal Forage Legume Mucuna pruriens (L.) DC

A Bowman-Birk protease, i.e., Mucuna pruriens trypsin inhibitor (MPTI), was purified from the seeds by 55.702-fold and revealed a single trypsin inhibitor on a zymogram with a specific activity of 202.31 TIU/mg of protein. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under non-reducing conditions, the protease trypsin inhibitor fraction [i.e., trypsin inhibitor non-reducing (TINR)] exhibited molecular weights of 74 and 37 kDa, and under reducing conditions [i.e., trypsin inhibitor reducing (TIR)], 37 and 18 kDa. TINR-37 revealed protease inhibitor activity on native PAGE and 37 and 18 kDa protein bands on SDS-PAGE. TINR-74 showed peaks corresponding to 18.695, 37.39, 56.085, and 74.78 kDa on ultra-performance liquid chromatography (UPLC) coupled with electrospray ionization/quadrupole time-of-flight-mass spectrometry (ESI/QTOF-MS). Similarly, TINR-37 displayed 18.695 and 37.39 kDa peaks. Furthermore, TIR-37 and TIR-18 exhibited peaks corresponding to 37.39 and 18.695 kDa. Multiple peaks observed by the UPLC-ESI/QTOF analysis revealed the multimeric association, confirming the characteristic and functional features of Bowman-Birk inhibitors (BBIs). The multimeric association helps to achieve more stability, thus enhancing their functional efficiency. MPTI was found to be a competitive inhibitor which again suggested that it belongs to the BBI family of inhibitors, displayed an inhibitor constant of 1.3 × 10^-6 M, and further demonstrates potent anti-inflammatory activity. The study provided a comprehensive basis for the identification of multimeric associates and their therapeutic potential, which could elaborate the stability and functional efficiency of the MPTI in the native state from M. pruriens.

Mast Cells Mediate Inflammatory Injury and Aggravate Neurological Impairment in Experimental Subarachnoid Hemorrhage Through Microglial PAR-2 Pathway

Subarachnoid hemorrhage (SAH) is a devastating cerebrovascular disease with high mortality and disability. Aberrant neuroinflammation has been identified as a critical factor accounting for the poor prognosis of SAH patients. Mast cells (MCs), the sentinel cells of the immune system, play a critical in the early immune reactions and participate in multiple pathophysiological process. However, the exact role of MCs on the pathophysiological process after SAH has not been fully understood. The current study was conducted to determine the role of MCs and MC stabilization in the context of SAH. Mouse SAH model was established by endovascular perforation process. Mice received saline or cromolyn (MC stabilizer) or compound 48/80 (MCs degranulator). Post-SAH evaluation included neurobehavioral test, western blot, immunofluorescence, and toluidine blue staining. We demonstrated that SAH induced MCs activation/degranulation. Administration of MC stabilizer cromolyn conferred a better neurologic outcome and decreased brain edema when compared with SAH+vehicle group. Furthermore, cromolyn significantly inhibited neuroinflammatory response and alleviated neuronal damage after SAH. However, pharmacological activation of MCs with compound 48/80 dramatically aggravated SAH-induced brain injury and exacerbated neurologic outcomes. Notably, pharmacological inhibition of microglial PAR-2 significantly reversed MCs-induced inflammatory response and neurological impairment. Additionally, the effect of MCs-derived tryptase in mediating neuroinflammation was also abolished by the microglial PAR-2 blockage in vitro. Taken together, MCs yielded inflammatory injury through activating microglia-related neuroinflammation after SAH. These data shed light on the notion that MCs might be a novel and promising therapeutic target for SAH.

WFDC Protein: A Promising Diagnosis Biomarker of Ovarian Cancer

An initial diagnosis of cancer is usually based on symptoms, abnormal physical examination and imaging tests. Ovarian cancer is difficult to be diagnosed timely due to the nonspecific symptoms, thus resulting in the high-risk mortality. Despite of the various diagnostic methods, there is still no reliable diagnostic test. Clinically, carbohydrate antigen 125(CA125) is widely recognized as a diagnosis biomarker of ovary cancer. However, CA125 is not sensitive to detect the ovary cancer at the early stage. It is essential to explore other potential biomarkers. Human epididymis protein 4 (HE4) in the whey/four-disulfide core (WFDC) proteins family shows satisfactory sensitivity in the early diagnosis of ovary cancer. In this present review, we summarized the important effects of WFDC family proteins on the proliferation, apoptosis and migration of ovary cancer and intended to provide more evidence to explore the possibility of WFDC protein as a diagnosis biomarker.