Structural basis of TMPRSS2 zymogen activation and recognition by the HKU1 seasonal coronavirus.

The human seasonal coronavirus HKU1-CoV, which causes common colds worldwide, relies on the sequential binding to surface glycans and transmembrane serine protease 2 (TMPRSS2) for entry into target cells. TMPRSS2 is synthesized as a zymogen that undergoes autolytic activation to process its substrates. Several respiratory viruses, in particular coronaviruses, use TMPRSS2 for proteolytic priming of their surface spike protein to drive membrane fusion upon receptor binding. We describe the crystal structure of the HKU1-CoV receptor binding domain in complex with TMPRSS2, showing that it recognizes residues lining the catalytic groove. Combined mutagenesis of interface residues and comparison across species highlight positions 417 and 469 as determinants of HKU1-CoV host tropism. The structure of a receptor-blocking nanobody in complex with zymogen or activated TMPRSS2 further provides the structural basis of TMPRSS2 activating conformational change, which alters loops recognized by HKU1-CoV and dramatically increases binding affinity.

Human coronavirus HKU1 recognition of the TMPRSS2 host receptor.

The human coronavirus HKU1 spike (S) glycoprotein engages host cell surface sialoglycans and transmembrane protease serine 2 (TMPRSS2) to initiate infection. The molecular basis of HKU1 binding to TMPRSS2 and determinants of host receptor tropism remain elusive. We designed an active human TMPRSS2 construct enabling high-yield recombinant production in human cells of this key therapeutic target. We determined a cryo-electron microscopy structure of the HKU1 RBD bound to human TMPRSS2, providing a blueprint of the interactions supporting viral entry and explaining the specificity for TMPRSS2 among orthologous proteases. We identified TMPRSS2 orthologs from five mammalian orders promoting HKU1 S-mediated entry into cells along with key residues governing host receptor usage. Our data show that the TMPRSS2 binding motif is a site of vulnerability to neutralizing antibodies and suggest that HKU1 uses S conformational masking and glycan shielding to balance immune evasion and receptor engagement.

TMPRSS2 and glycan receptors synergistically facilitate coronavirus entry.

The entry of coronaviruses is initiated by spike recognition of host cellular receptors, involving proteinaceous and/or glycan receptors. Recently, TMPRSS2 was identified as the proteinaceous receptor for HCoV-HKU1 alongside sialoglycan as a glycan receptor. However, the underlying mechanisms for viral entry remain unknown. Here, we investigated the HCoV-HKU1C spike in the inactive, glycan-activated, and functionally anchored states, revealing that sialoglycan binding induces a conformational change of the NTD and promotes the neighboring RBD of the spike to open for TMPRSS2 recognition, exhibiting a synergistic mechanism for the entry of HCoV-HKU1. The RBD of HCoV-HKU1 features an insertion subdomain that recognizes TMPRSS2 through three previously undiscovered interfaces. Furthermore, structural investigation of HCoV-HKU1A in combination with mutagenesis and binding assays confirms a conserved receptor recognition pattern adopted by HCoV-HKU1. These studies advance our understanding of the complex viral-host interactions during entry, laying the groundwork for developing new therapeutics against coronavirus-associated diseases.

Novel proteolytic activation of Ebolavirus glycoprotein GP by TMPRSS2 and cathepsin L at an uncharted position can compensate for furin cleavage.

A multistep priming process involving furin and endosomal cathepsin B and L (CatB/L) has been described for the Orthoebolavirus zairense (EBOV) glycoprotein GP. Inhibition or knockdown of either furin or endosomal cathepsins, however, did not prevent virus multiplication in cell cultures. Moreover, an EBOV mutant lacking the furin cleavage motif (RRTRR→AGTAA) was able to replicate and cause fatal disease in nonhuman primates, indicating that furin cleavage may be dispensable for virus infectivity. Here, by using protease inhibitors and EBOV GP-carrying recombinant vesicular stomatitis virus (VSV) and transcription and replication-competent virus-like particles (trVLPs) we found that processing of EBOV GP is mediated by different proteases in different cell lines depending on the protease repertoire available. Endosomal cathepsins were essential for EBOV GP entry in Huh-7 but not in Vero cells, in which trypsin-like proteases and stably expressed trypsin-like transmembrane serine protease 2 (TMPRSS2) supported wild-type EBOV GP and EBOV GP_AGTAA mutant entry. Furthermore, we show that the EBOV GP_AGTAA mutant is cleaved into fusion-competent GP2 by TMPRSS2 and by CatL at a so far unknown site. Fluorescence microscopy co-localization studies indicate that EBOV GP cleavage by TMPRSS2 may occur in the TGN prior to virus release or in the late endosome at the stage of virus entry into a new cell. Our data show that EBOV GP must be proteolytically activated to support virus entry but has even greater flexibility in terms of proteases and the precise cleavage site than previously assumed.

SARS-CoV-2 inhibitory potential of fish oil-derived 2-pyrone compounds by acquiring linoleic acid binding site on the spike protein.

Traditional medicines have reportedly treated SARS-CoV-2 infection. Substantial evidence shows that fish oil supplements promote human immune function, suggesting they may lessen susceptibility to SARS-CoV-2 infection and suppress viral replication by inducing interferon. Fish oil was subjected to partition chromatography and separated into two compounds (EP01 and DH01). Isolated compounds were purified and characterized using UV, FTIR, NMR, and mass spectrometry to confirm their identity. Molecular docking was studied on the SARS CoV-2 variants of concern; SARS CoV-2 WT (PDB: 6VXX), SARS CoV-2 Alpha variant (PDB: 7LWS), SARS CoV-2 Delta variant (PDB: 7TOU), SARS CoV-2 Gamma variant (PDB: 7V78), SARS CoV-2 Kappa variant (PDB: 7VX9), and SARS CoV-2 Omicron variant (PDB: 7QO7) and TMPRSS2 (PDB: 7Y0E). Further selected protein-ligand complexes were subjected to 100 ns MD simulations to predict their biological potential in the SARS-CoV-2 treatment. In-vitro biological studies were carried out to support in-silico findings. Isolated compounds EP01 and DH01 were identified as 5-Tridecyltetrahydro-2H-pyran-2-one and 5-Heptadecyltetrahydro-2H-pyran-2-one, respectively. The compound EP01 significantly reduced (93.24 %) the viral RNA copy number with an IC50 of ~8.661 µM. EP01 proved to be a potent antiviral by in-vitro method against the SARS-CoV-2 clinical isolate, making it a promising antiviral candidate, with a single dose capable of preventing viral replication.

Human Lung Mast Cells as a Possible Reservoir for Coronavirus: A Novel Unrecognized Mechanism for SARS-CoV-2 Immune-Mediated Pathology.

The pathogenic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global health concern. Cell entry of SARS-CoV-2 depends on viral spike (S) proteins binding to cellular receptors (ACE2) and their subsequent priming by host cell proteases (TMPRSS2). Assessing effects of viral-induced host response factors and determining which cells are used by SARS-CoV-2 for entry might provide insights into viral transmission, add clarity to the virus' pathogenesis, and possibly reveal therapeutic targets. Mast cells (MCs) are ubiquitously expressed tissue cells that act as immune sentinels given their ability to react specifically to pathogens at environmental interfaces, such as in the lung. Several lines of evidence suggest a critical role for MCs in SARS-CoV-2 infections based on patients' mediator profiles, especially the "cytokine storm" responsible for most morbidity and mortality. In this pilot study, we demonstrated that human lung MCs (n = 3 donors) are a source of renin and that they upregulate the membrane receptor for SARS-CoV-2 (ACE2) as well as the protease required for cellular entry (TMPRSS2) under certain conditions. We hypothesized that infection of human MCs with SARS-CoV-2 may be a heretofore-unrecognized mechanism of viral pathogenesis, and further studies are required to assess this question.

Anti-SARS-CoV-2 Viral Activity of Sweet Potato Trypsin Inhibitor via Downregulation of TMPRSS2 Activity and ACE2 Expression In Vitro and In Vivo.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic. Known as COVID-19, it has affected billions of people worldwide, claiming millions of lives and posing a continuing threat to humanity. This is considered one of the most extensive pandemics ever recorded in human history, causing significant losses to both life and economies globally. However, the available evidence is currently insufficient to establish the effectiveness and safety of antiviral drugs or vaccines. The entry of the virus into host cells involves binding to angiotensin-converting enzyme 2 (ACE2), a cell surface receptor, via its spike protein. Meanwhile, transmembrane protease serine 2 (TMPRSS2), a host surface protease, cleaves and activates the virus's S protein, thus promoting viral infection. Plant protease inhibitors play a crucial role in protecting plants against insects and/or microorganisms. The major storage proteins in sweet potato roots include sweet potato trypsin inhibitor (SWTI), which accounts for approximately 60% of the total water-soluble protein and has been found to possess a variety of health-promoting properties, including antioxidant, anti-inflammatory, ACE-inhibitory, and anticancer functions. Our study found that SWTI caused a significant reduction in the expression of the ACE2 and TMPRSS2 proteins, without any adverse effects on cells. Therefore, our findings suggest that the ACE2 and TMPRSS2 axis can be targeted via SWTI to potentially inhibit SARS-CoV-2 infection.

TMPRSS2 is a tumor suppressor and its downregulation promotes antitumor immunity and immunotherapy response in lung adenocarcinoma.

BACKGROUND: TMPRSS2, a key molecule for SARS-CoV-2 invading human host cells, has an association with cancer. However, its association with lung cancer remains insufficiently unexplored. METHODS: In five bulk transcriptomics datasets, one single-cell RNA sequencing (scRNA-seq) dataset and one proteomics dataset for lung adenocarcinoma (LUAD), we explored associations between TMPRSS2 expression and immune signatures, tumor progression phenotypes, genomic features, and clinical prognosis in LUAD by the bioinformatics approach. Furthermore, we performed experimental validation of the bioinformatics findings. RESULTS: TMPRSS2 expression levels correlated negatively with the enrichment levels of both immune-stimulatory and immune-inhibitory signatures, while they correlated positively with the ratios of immune-stimulatory/immune-inhibitory signatures. It indicated that TMPRSS2 levels had a stronger negative correlation with immune-inhibitory than with immune-stimulatory signatures. TMPRSS2 downregulation correlated with increased proliferation, stemness, genomic instability, tumor progression, and worse survival in LUAD. We further validated that TMPRSS2 was downregulated with tumor progression in the LUAD cohort we collected from Jiangsu Cancer Hospital, China. In vitro and in vivo experiments verified the association of TMPRSS2 deficiency with increased tumor cell proliferation and invasion and antitumor immunity in LUAD. Moreover, in vivo experiments demonstrated that TMPRSS2-knockdown tumors were more sensitive to BMS-1, an inhibitor of PD-1/PD-L1. CONCLUSIONS: TMPRSS2 is a tumor suppressor, while its downregulation is a positive biomarker of immunotherapy in LUAD. Our data provide a potential link between lung cancer and pneumonia caused by SARS-CoV-2 infection.

Comparison of DASH diet score and total antioxidant capacity of diet on serum levels of TMPRSS-2, inflammatory biomarkers, and disease severity in COVID-19 patients: A case-control study.

There is evidence that healthy diets improve the immune system and lessen the severity of infectious diseases such as COVID-19. We have investigated whether the dietary total antioxidant capacity (TAC) and dietary approach to stop hypertension (DASH) score could be associated with the occurrence and clinical outcomes of COVID-19. This case-control study included 120 adults who were admitted to the hospital. Dietary TAC and DASH diet scores were determined by a 138-item semi-quantitative food frequency questionnaire (FFQ). Inflammation-related markers including C-reactive protein (CRP) and transmembrane protease serine 2 (TMPRSS-2) differential were measured. Also, using chest radiology criteria, the severity of the disease was evaluated. The mean CRP values in the lowest and highest tertiles of either dietary TAC or DASH diet scores were 9.44 ± 11.26 and 3.52 ± 4.83 mg/dL (p = .003) or 9.04 ± 11.23 and 4.40 ± 6.23 mg/dL (p = .013), respectively. Individuals with higher dietary TAC were at a lower risk of COVID-19 (OR: 0.06, p < ·0001). Individuals with greater DASH diet scores were also at decreased odds of COVID-19 (OR: 0.12, p < ·0001). No significant associations were found between dietary TAC and DASH diet scores with severity of COVID-19 disease, CRP, or TMPRSS-2 (p > 0.05). The study found that adherence to a diet with higher dietary TAC and DASH diet scores may be protective against COVID-19 and improve outcomes of the disease. More research is needed to corroborate these findings.

Dandelion root extracts and taraxasterol inhibit LPS­induced colorectal cancer cell viability by blocking TLR4­NFκB­driven ACE2 and TMPRSS2 pathways.

Colorectal cancer is the fourth leading cause of cancer-related death worldwide. Notably, abnormalities in intestinal bacteria may contribute to the initiation or progression of colorectal cancer. Lipopolysaccharide (LPS), a bacterial endotoxin, is elevated in patients with colorectal cancer. The present study investigated the protective effects of dandelion root extracts and taraxasterol (TS; a major pharmacologically active compound in dandelion root extracts) on LPS-induced colorectal cancer cell viability, as well as the underlying mechanisms. Cell viability was assessed by MTT assay, and protein and gene expression levels were determined by western blotting and quantitative PCR. It was revealed that LPS at a low dose (0.5 µg/ml) significantly promoted the viability of human colorectal cancer cells but did not affect normal colon epithelial cells. The addition of dandelion root extracts (0.1-1 mg/ml) or TS (0.05-1 µg/ml) was able to reverse the LPS-induced increase in colorectal cancer cell viability and colony formation. Mechanistically, dandelion root extracts or TS may inhibit the LPS-promoted toll-like receptor 4 (TLR4)/NFκB-p65 pathway and transcription levels of pro-inflammatory genes (TNFα, IL4 and IL6). Compared with normal colon epithelial cells, human colorectal cancer cells had higher expression levels of angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), which could be further enhanced by LPS treatment but this was reversed by co-incubation with dandelion root extracts or TS. In addition, suppression of the TLR4/NFκB-p65 pathway with CLI095 significantly reversed the stimulatory effect of LPS on the expression levels of ACE2 and TMPRSS2, whereas TNFα (10 ng/ml) markedly induced the expression levels of ACE2 and TMPRSS2. In conclusion, the present study suggested that dandelion root extracts and TS could be used as prevention strategies for reversing bacteria-driven colorectal cancer cell viability.

In silico evidence that substitution of glycine for valine (p.G8V) in a common variant of TMPRSS2 isoform 1 increases accessibility to an endocytic signal: Implication for SARS-cov-2 entry into host cells and susceptibility to COVID-19.

The TMPRSS2 protease plays a key role in the entry of the SARS-CoV-2 into cells. The TMPRSS2 gene is highly polymorphic in humans, and some polymorphisms may affect the susceptibility to COVID-19 or disease severity. rs75603675 (c.23G > T) is a missense variant that causes the replacement of glycine with valine at position 8 (p.G8V) in the TMPRSS2 isoform 1. According to GnomAD v4.0.0 database, the allele frequency of the rs75603675 on a global scale is 38.10 %, and range from 0.92 % in East Asian to 40.77 % in non-Finnish European (NFE) population. We analyzed the occurrence of the rs75603675 in two cohorts of patients, the first with severe/critical COVID-19 enrolled in a French hospital (42 patients), and the second with predominantly asymptomatic/pauci-symptomatic/mild COVID-19 enrolled in an Italian hospital (69 patients). We found that the TMPRSS2-c.23T minor allele frequency was similar in the two cohorts, 46.43 % and 46.38 %, respectively, and higher than the frequency in the NFE population (40.77 %). Chi-square test provided significant results (p < 0.05) when the genotype data (TMPRSS2-c.23T/c.23T homozygotes + TMPRSS2-c.23G/c.23T heterozygotes vs. TMPRSS2-c.23G/c.23G homozygotes) of the two patient groups were pooled and compared to the expected data for the NFE population, suggesting a possible pathogenetic mechanism of the p.G8V substitution. We explored the possible effects of the p.G8V substitution and found that the N-terminal region of the TMPRSS2 isoform 1 contains a signal for clathrin/AP-2-dependent endocytosis. In silico analysis predicted that the p.G8V substitution may increase the accessibility to the endocytic signal, which could help SARS-CoV-2 enter cells.

Mapping ACE2 and TMPRSS2 co-expression in human brain tissue: implications for SARS-CoV-2 neurological manifestations.

The Coronavirus Disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) primarily targets respiratory cells, but emerging evidence shows neurological involvement, with the virus directly affecting neurons and glia. SARS-CoV-2 entry into a target cell requires co-expression of ACE2 (Angiotensin-converting enzyme-2) and TMPRSS2 (Trans membrane serine protease-2). Relevant literature on human neurological tissue is sparse and mostly focused on the olfactory areas. This prompted our study to map brain-wide expression of these entry proteins and assess age-related changes. The normal brain tissue samples were collected from cerebral cortex, hippocampus, basal ganglia, thalamus, hypothalamus, brain stem and cerebellum; and were divided into two groups - up to 40 years (n = 10) and above 40 years (n = 10). ACE2 and TMPRSS2 gene expression analysis was done using qRT-PCR and protein co-expression was seen by immunofluorescence. The ACE2 and TMPRSS2 gene expression was observed to be highest in hypothalamus and thalamus regions, respectively. Immunoreactivity for both ACE-2 and TMPRSS2 was observed in all examined brain regions, confirming the presence of these viral entry receptors. Co-localisation was maximum in hypothalamus. Our study did not find any trend related to different age groups. The expression of both these viral entry receptors suggests that normal human brain is susceptibility to SARS-CoV-2, perhaps which could be related to the cognitive and neurological impairment that occur in patients.

Prediction of deleterious non-synonymous SNPs of TMPRSS2 protein combined with Molecular Dynamics Simulations and free energy analysis to identify the potential peptide substrates against SARS-CoV-2.

Globally the SARS-CoV-2 viral infection demands for the new drugs, the TMPRSS2 target plays a vital role in facilitating the virus entry. The aim of the present study is to identify the potential peptide substrate from the Anti-viral database against TMPRSS2 of SARS-CoV-2. The compound screening and variation analysis were performed using molecular docking analysis and online tools such as PROVEAN and SNAP2 server, respectively. The re-docked crystal structure peptide substrate exhibits -128.151 kcal/mol whereas the RRKK peptide substrate shows -134.158 kcal/mol. Further, the selected compounds were proceeded with Molecular Dynamics Simulation, it explores the stability of the complex by revealing the hotspot residues (His296 and Ser441) were active for nucleophilic attack against TMPRSS2. The average Binding Free Energy values computed through MM/GBSA for RRKK, Camostat, and Crystal Structure were shown -69.9278 kcal/mol, -64.5983 kcal/mol, and -63.9755 kcal/mol, respectively against TMPRSS2. The 'rate of acylation' emerges as an indicator for RRKK's efficacy, it maintains the distance of 3.2 Å with Ser441 resembles, whilst its -NH backbone stabilizes at 2.5 Å 'Michaelis Complex' which leads to prevent the entry of SARS-CoV-2 to human cells. The sequence variation analysis explores that the V160 and G6 substitutions are essential to emphasize the uncover possibilities for the ongoing drug discovery research. Therefore, the identified peptide substrate found to be potent against SARS-CoV-2 and these results will be valuable for ongoing drug discovery research.Communicated by Ramaswamy H. Sarma.

Efficacy of host cell serine protease inhibitor MM3122 against SARS-CoV-2 for treatment and prevention of COVID-19.

We developed a novel class of peptidomimetic inhibitors targeting several host cell human serine proteases, including transmembrane protease serine 2 (TMPRSS2), matriptase, and hepsin. TMPRSS2 is a membrane-associated protease that is highly expressed in the upper and lower respiratory tracts and is utilized by SARS-CoV-2 and other viruses to proteolytically process their glycoproteins, enabling host cell entry, replication, and dissemination of new virus particles. We have previously shown that compound MM3122 exhibited subnanomolar potency against all three proteases and displayed potent antiviral effects against SARS-CoV-2 in a cell viability assay. Herein, we demonstrate that MM3122 potently inhibits viral replication in human lung epithelial cells and is also effective against the EG.5.1 variant of SARS-CoV-2. Furthermore, we evaluated MM3122 in a mouse model of COVID-19 and demonstrated that MM3122 administered intraperitoneally (IP) before (prophylactic) or after (therapeutic) SARS-CoV-2 infection had significant protective effects against weight loss and lung congestion and reduced pathology. Amelioration of COVID-19 disease was associated with a reduction in proinflammatory cytokine and chemokine production after SARS-CoV-2 infection. Prophylactic, but not therapeutic, administration of MM3122 also reduced virus titers in the lungs of SARS-CoV-2-infected mice. Therefore, MM3122 is a promising lead candidate small-molecule drug for the treatment and prevention of infections caused by SARS-CoV-2 and other coronaviruses. IMPORTANCE: SARS-CoV-2 and other emerging RNA coronaviruses are a present and future threat in causing widespread endemic and pandemic infection and disease. In this paper, we have shown that the novel host cell protease inhibitor, MM3122, blocks SARS-CoV-2 viral replication and is efficacious as both a prophylactic and a therapeutic drug for the treatment of COVID-19 given intraperitoneally in mice. Targeting host proteins and pathways in antiviral therapy is an underexplored area of research, but this approach promises to avoid drug resistance by the virus, which is common in current antiviral treatments.

Discovery and development of novel 10,12-disubstituted aloperine derivatives against HCoV-OC43 by targeting allosteric site of host TMPRSS2.

By inducing steric activation of the 10CH bond with a 12-acyl group to form a key imine oxime intermediate, 20 novel (10S)-10,12-disubstituted aloperine derivatives were successfully synthesized and assessed for their antiviral efficacy against HCoV-OC43. Of them, compound 3i exhibited the moderate activities against HCoV-OC43, as well as against the SARS-CoV-2 variant EG.5.1 with the comparable EC50 values of 4.7 and 4.1 µM. A mechanism study revealed that it inhibited the protease activity of host TMPRSS2 by binding to an allosteric site, rather than the known catalytic center, different from that of camostat. Also, the combination of compound 3i and molnupiravir, as an RdRp inhibitor, showed an additive antiviral effect against HCoV-OC43. The results provide a new binding mode and lead compound for targeting TMPRSS2, with an advantage in combating broad-spectrum coronavirus.

ACE2 and TMPRSS2 expression in patients before, during, and after SARS-CoV-2 infection.

During the SARS-CoV-2 pandemic angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) were constantly under the scientific spotlight, but most studies evaluated ACE2 and TMPRSS2 expression levels in patients infected by SARS-CoV-2. Thus, this study aimed to evaluate the expression levels of both proteins before, during, and after-infection. For that, nasopharyngeal samples from 26 patients were used to measure ACE2/TMPRSS2 ex-pression via qPCR. Symptomatic patients presented lower ACE2 expression levels before and after the infection than those in asymptomatic patients; however, these levels increased during SARS-CoV-2 infection. In addition, symptomatic patients presented higher expression levels of TMPRSS2 pre-infection, which decreased in the following periods. In summary, ACE2 and TMPRSS2 expression levels are potential risk factors for the development of symptomatic COVID-19, and the presence of SARS-CoV-2 potentially modulates those levels.

Sambou Bamboo salt™ down-regulates the expression levels of angiotensin-converting enzyme 2 in activated human mast cells.

Mast cells have a detrimental impact on coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Sambou Bamboo salt™ (BS) suppresses mast cell-mediated inflammatory response and enhances immunity. In this study, we investigated the regulatory effects of BS on expression of angiotensin-converting enzyme 2 (ACE2) and transmembrane protease/serine subfamily member 2 (TMPRSS2) in human mast cell line (HMC)-1 cells. BS resulted in significant reductions in expression levels of ACE2 and TMPRSS2 in activated HMC-1 cells. Levels of tryptase were reduced by BS. In addition, BS blocked activation of activator protein 1 (AP-1), c-Jun NH2-terminal kinases (JNK), p38, and phosphatidylinositide-3-kinase (PI3K) in activated HMC-1 cells. Therefore, these results show that BS reduces levels of ACE2, TMPRSS2, and tryptase by inhibiting AP-1/JNK/p38/PI3K signaling pathways in mast cells. These findings can serve as valuable foundational data for the development of therapeutic agents aimed at preventing SARS-CoV-2 infection.

Post-therapeutic squamous cell transformation of a metastatic prostate adenocarcinoma with comparison of molecular profiles: a case report and review of the literature.

Transformation of primary prostate adenocarcinoma to squamous cell carcinoma after initial treatment with chemotherapy and hormonal therapy is extremely rare and typically results in rapid treatment-refractory disease progression and death. Here, we present a case of a 64-year-old man who was initially diagnosed with metastatic prostate adenocarcinoma (positive PSA and NKX3.1 stains, total PSA 747.2 ng/ml) to the thoracic spine (T8) in 2019. The patient received androgen deprivation therapy and chemotherapy with good response (PSA 2.53 ng/ml). In 2022, the patient had a tumor resection from the left humerus with a consequent fracture. Pathology showed pure squamous carcinoma without any adenocarcinoma component (PSA and NKX3.1 stains negative and weak p504s stain, PSA 19.82 ng/ml). Given the patient's history of metastatic prostate adenocarcinoma and no history of any other malignancies, a diagnosis of squamous carcinoma transformed from prostate adenocarcinoma was rendered. The patient passed away in 2023. Molecular profiling identified the same TP53 mutation and two variants of uncertain significance in both specimens, suggesting the same primary. However, there was CCND3 amplification and absence of the TMPRSS2::ETV4 fusion in the 2022 specimen, which may be associated with squamous transformation and poor prognosis. A microarray might be beneficial to confirm loss of the TMPRSS2::ETV4 fusion. This case illustrates the rare occurrence of squamous transformation in prostate adenocarcinoma and the aggressive clinical course, and need for more therapy guidance and prognostic studies. It also highlights the importance of molecular profiling to provide insights into the pathogenesis of histologic transformation.

The fatal contribution of serine protease-related genetic variants to COVID-19 outcomes.

Introduction: Serine proteases play a critical role during SARS-CoV-2 infection. Therefore, polymorphisms of transmembrane protease serine 2 (TMPRSS2) and serpine family E member 1 (SERPINE1) could help to elucidate the contribution of variability to COVID-19 outcomes. Methods: To evaluate the genetic variants of the genes previously associated with COVID-19 outcomes, we performed a cross-sectional study in which 1536 SARS-CoV-2-positive participants were enrolled. TMPRSS2 (rs2070788, rs75603675, rs12329760) and SERPINE1 (rs2227631, rs2227667, rs2070682, rs2227692) were genotyped using the Open Array Platform. The association of polymorphisms with disease outcomes was determined by logistic regression analysis adjusted for covariates (age, sex, hypertension, type 2 diabetes, and obesity). Results: According to our codominant model, the GA genotype of rs2227667 (OR=0.55; 95% CI = 0.36-0.84; p=0.006) and the AG genotype of rs2227667 (OR=0.59; 95% CI = 0.38-0.91; p=0.02) of SERPINE1 played a protective role against disease. However, the rs2227692 T allele and TT genotype SERPINE1 (OR=1.45; 95% CI = 1.11-1.91; p=0.006; OR=2.08; 95% CI = 1.22-3.57; p=0.007; respectively) were associated with a decreased risk of death. Similarly, the rs75603675 AA genotype TMPRSS2 had an OR of 1.97 (95% CI = 1.07-3.6; p=0.03) for deceased patients. Finally, the rs2227692 T allele SERPINE1 was associated with increased D-dimer levels (OR=1.24; 95% CI = 1.03-1.48; p=0.02). Discussion: Our data suggest that the rs75603675 TMPRSS2 and rs2227692 SERPINE1 polymorphisms are associated with a poor outcome. Additionally, rs2227692 SERPINE1 could participate in hypercoagulable conditions in critical COVID-19 patients, and this genetic variant could contribute to the identification of new pharmacological targets and treatment strategies to block the inhibition of TMPRSS2 entry into SARS-CoV-2.

Artemisia argyi extracts overcome lapatinib resistance via enhancing TMPRSS2 activation in HER2-positive breast cancer.

Breast cancer stands as the predominant malignancy and primary cause of cancer-related mortality among females globally. Approximately 25% of breast cancers exhibit HER2 overexpression, imparting a more aggressive tumor phenotype and correlating with poor prognoses. Patients with metastatic breast cancer receiving HER2 tyrosine kinase inhibitors (HER2 TKIs), such as Lapatinib, develop acquired resistance within a year, posing a critical challenge in managing this disease. Here, we explore the potential of Artemisia argyi, a Chinese herbal medicine known for its anti-cancer properties, in mitigating HER2 TKI resistance in breast cancer. Analysis of the Cancer Genome Atlas (TCGA) revealed diminished expression of transmembrane serine protease 2 (TMPRSS2), a subfamily of membrane proteolytic enzymes, in breast cancer patients, correlating with unfavorable outcomes. Intriguingly, lapatinib-responsive patients exhibited higher TMPRSS2 expression. Our study unveiled that the compounds from Artemisia argyi, eriodictyol, and umbelliferone could inhibit the growth of lapatinib-resistant HER2-positive breast cancer cells. Mechanistically, they suppressed HER2 kinase activation by enhancing TMPRSS2 activity. Our findings propose TMPRSS2 as a critical determinant in lapatinib sensitivity, and Artemisia argyi emerges as a potential agent to overcome lapatinib via activating TMPRSS2 in HER2-positive breast cancer. This study not only unravels the molecular mechanisms driving cell death in HER2-positive breast cancer cells induced by Artemisia argyi but also lays the groundwork for developing novel inhibitors to enhance therapy outcomes.