Entangling of Peptide Nanofibers Reduces the Invasiveness of SARS-CoV-2.

The viral spike (S) protein on the surface of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binds to angiotensin-converting enzyme 2 (ACE2) receptors on the host cells, facilitating its entry and infection. Here, functionalized nanofibers targeting the S protein with peptide sequences of IRQFFKK, WVHFYHK and NSGGSVH, which are screened from a high-throughput one-bead one-compound screening strategy, are designed and prepared. The flexible nanofibers support multiple binding sites and efficiently entangle SARS-CoV-2, forming a nanofibrous network that blocks the interaction between the S protein of SARS-CoV-2 and the ACE2 on host cells, and efficiently reduce the invasiveness of SARS-CoV-2. In summary, nanofibers entangling represents a smart nanomedicine for the prevention of SARS-CoV-2.

A bat MERS-like coronavirus circulates in pangolins and utilizes human DPP4 and host proteases for cell entry.

It is unknown whether pangolins, the most trafficked mammals, play a role in the zoonotic transmission of bat coronaviruses. We report the circulation of a novel MERS-like coronavirus in Malayan pangolins, named Manis javanica HKU4-related coronavirus (MjHKU4r-CoV). Among 86 animals, four tested positive by pan-CoV PCR, and seven tested seropositive (11 and 12.8%). Four nearly identical (99.9%) genome sequences were obtained, and one virus was isolated (MjHKU4r-CoV-1). This virus utilizes human dipeptidyl peptidase-4 (hDPP4) as a receptor and host proteases for cell infection, which is enhanced by a furin cleavage site that is absent in all known bat HKU4r-CoVs. The MjHKU4r-CoV-1 spike shows higher binding affinity for hDPP4, and MjHKU4r-CoV-1 has a wider host range than bat HKU4-CoV. MjHKU4r-CoV-1 is infectious and pathogenic in human airways and intestinal organs and in hDPP4-transgenic mice. Our study highlights the importance of pangolins as reservoir hosts of coronaviruses poised for human disease emergence.

USP18 contributes to the proliferation and migration of ovarian cancer cells by regulating the AKT/mTOR signaling pathway.

Ubiquitin-specific peptidase (USP)18 is elevated in tumor tissues and is associated with tumor malignancy. USP18 functions as an oncogene in different cancers. However, the role of USP18 in ovarian cancer was poorly understood. TCGA database showed that USP18 was elevated in ovarian cancer tissues. Additionally, USP18 mRNA and protein expression was also up-regulated in tumor tissues. The functional assays were then designed via siRNA-mediated knockdown of USP18. The results showed that knockdown of USP18 reduced cell viability and ovarian cancer proliferation. Furthermore, cell apoptosis was promoted by USP18 silencing, and interference of USP18 suppressed cell migration and invasion. The expression of phosphorylated AKT (p-AKT) and p-mTOR protein was decreased in ovarian cancer cells by USP18 knockdown. Inhibition of AKT attenuated the decrease in cell apoptosis induced by USP18 overexpression and increased cell viability and migration. In conclusion, USP18 promoted the proliferation and migration of ovarian cancer cells by activating AKT/mTOR signaling.

IFP35 as a promising biomarker and therapeutic target for the syndromes induced by SARS-CoV-2 or influenza virus.

Previous studies have shown that the high mortality caused by viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza virus primarily results from complications of a cytokine storm. Therefore, it is critical to identify the key factors participating in the cytokine storm. Here we demonstrate that interferon-induced protein 35 (IFP35) plays an important role in the cytokine storm induced by SARS-CoV-2 and influenza virus infection. We find that the levels of serum IFP35 in individuals with SARS-CoV-2 correlates with severity of the syndrome. Using mouse model and cell assays, we show that IFP35 is released by lung epithelial cells and macrophages after SARS-CoV-2 or influenza virus infection. In addition, we show that administration of neutralizing antibodies against IFP35 considerably reduces lung injury and, thus, the mortality rate of mice exposed to viral infection. Our findings suggest that IFP35 serves as a biomarker and as a therapeutic target in virus-induced syndromes.

Structure of Mpro from SARS-CoV-2 and discovery of its inhibitors.

A new coronavirus, known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is the aetiological agent responsible for the 2019-2020 viral pneumonia outbreak of coronavirus disease 2019 (COVID-19)1-4. Currently, there are no targeted therapeutic agents for the treatment of this disease, and effective treatment options remain very limited. Here we describe the results of a programme that aimed to rapidly discover lead compounds for clinical use, by combining structure-assisted drug design, virtual drug screening and high-throughput screening. This programme focused on identifying drug leads that target main protease (Mpro) of SARS-CoV-2: Mpro is a key enzyme of coronaviruses and has a pivotal role in mediating viral replication and transcription, making it an attractive drug target for SARS-CoV-25,6. We identified a mechanism-based inhibitor (N3) by computer-aided drug design, and then determined the crystal structure of Mpro of SARS-CoV-2 in complex with this compound. Through a combination of structure-based virtual and high-throughput screening, we assayed more than 10,000 compounds-including approved drugs, drug candidates in clinical trials and other pharmacologically active compounds-as inhibitors of Mpro. Six of these compounds inhibited Mpro, showing half-maximal inhibitory concentration values that ranged from 0.67 to 21.4 µM. One of these compounds (ebselen) also exhibited promising antiviral activity in cell-based assays. Our results demonstrate the efficacy of our screening strategy, which can lead to the rapid discovery of drug leads with clinical potential in response to new infectious diseases for which no specific drugs or vaccines are available.

Overexpression of miR-671-5p indicates a poor prognosis in colon cancer and accelerates proliferation, migration, and invasion of colon cancer cells.

PURPOSE: Colon cancer is one of the common malignancies worldwide, and many genes, including microRNAs (miRNAs), have been demonstrated that associated with progression of various diseases, including cancers. The aim of this study is to investigate the potential role of miR-671-5p in colon cancer. PATIENTS AND METHODS: Reverse transcription-quantitative polymerase chain reaction (qRT-PCR) was performed to detect the expression levels of miR-671-5p in 115 paired colon cancer tissues and adjacent normal tissues, as well as in colon cancer cells. Kaplan-Meier curve and Cox regression analyses were used to estimate the prognostic significance of miR-671-5p in colon cancer. CCK-8 assay, colony-formation assay, Transwell migration and invasion assays were used to evaluate the effects of miR-671-5p on cell proliferation, migration, and invasion in colon cancer. RESULTS: We found that miR-671-5p expression was increased in colon cancer tissues and cell lines. Overexpression of miR-671-5p was found associated with lymph node metastasis, TNM stage, and poor overall survival of patients with colon cancer. By exploiting miR-671-5p mimics and inhibitors, miR-671-5p overexpression significantly increased cell proliferation, migration, and invasion, while downregulation of miR-671-5p inhibited proliferation, migration, and invasion of colon cancer cells. CONCLUSION: Taken together, miR-671-5p may act as an oncogene in colon cancer and promote proliferation, migration, and invasion of colon cancer cells by targeting TRIM67. And it may be a promising prognostic biomarker and therapeutic application for colon cancer treatment.

Identification and interaction analysis of key miRNAs in medullary thyroid carcinoma by bioinformatics analysis.

Medullary thyroid carcinoma (MTC) is an endocrine tumor and comprises 5­10% of all primary thyroid malignancies. However, the biomechanical contribution to the development and progression of MTC remains unclear. In this study, To discover the key microRNAs (miRNAs or miRs) and their potential roles in the tumorigenesis of MTC, the microarray datasets GSE97070, GSE40807 and GSE27155 were analyzed. The datasets were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed miRNAs (DEMs) and genes (DEGs) were accessed by R. Targets of DEMs and predicted using starBase, and functional and pathway enrichment analyses were performed using Metascape. A protein­protein interaction (PPI) network and an analysis of modules were constructed using NetworkAnalyst. Finally, a network was constructed to show the regulatory association between transcription factors (TFs), DEMs and downstream genes. A total of 5 DEMs were found both in GSE97070 and GSE40807, including 3 upregulated DEMs and 2 downregulated DEMs. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses from Metascape revealed that the target genes of upregulated DEMs were significantly enriched in adherens junction, kinase and protein binding, while the target genes of downregulated DEMs were mainly involved in non­canonical Wnt signaling pathway and RNA transport. From the PPI network, 13 nodes were screened as hub genes. Pathway enrichment analysis revealed that the top 5 modules were mostly enriched in the neurotrophin signaling pathway, mRNA surveillance pathway and MAPK signaling pathway. In addition, the TF­DEMs­target gene and DEGs regulatory network revealed that 17 TFs regulated 2 miRNAs, including upregulated or downregulated DEMs, CREB1 regulated all upregulated DEMs, and TGFB1 was an activator of hsa­miR­199a­3p and a repressor of hsa­miR­429. Taken together, the present study identified several miRNAs and potential biological mechanisms involved in the tumorigenesis of MTC. This study identified the key DEMs and potential mechanisms underlying the development of MTC, and provided a series of biomarkers and targets for the management of MTC.

Nestin Expression Is Associated with Poor Clinicopathological Features and Prognosis in Glioma Patients: an Association Study and Meta-analysis.

Nestin has been identified as a molecular marker of neural progenitor cells and putative glioma stem cells (GSCs). Various studies examining the relationship between nestin expression with the clinical outcome in glioma patients have yielded inconclusive results. Thus, we conducted a systematic review to evaluate the association of nestin with prognosis and clinicopathological features of glioma patients. The electronic searches were performed through the database of PubMed, MEDLINE, Embase, and CNKI. In total, this meta-analysis included 14 studies covering 897 nestin + cases and 704 controls. The correlation between nestin expression and clinicopathological or prognostic parameters was evaluated by Stata 11.0 software. Our results showed that nestin protein abundance was significantly correlated with the histological grade [odds ratio (OR) = 4.36, 95 % confidence interval (CI) = 2.14-8.88, P = 0.003] of glioma. With respect to prognosis, nestin expression was positively correlated with overall survival (OS) [hazard ratio (HR) = 1.98, 95 % CI = 1.30-3.02, P = 0.000] and progression-free survival (PFS) (HR = 1.90, 95 % CI = 1.18-3.07, P = 0.040). The further stratified analysis not only defined the predictive function of nestin in different ages but also revealed that different antibodies did not alter the positive outcomes and higher standard cutoff values were more suitable for the accurate assay of nestin. Taken together, our results indicate that nestin may play an important role in the prediction of the clinicopathology and poor prognosis of glioma patients. This study should be taken into consideration in the development of new diagnostic and therapeutic programs.

Serum human epididymis protein 4 (HE4) may be a better tumor marker in early lung cancer.

BACKGROUND: Human epididymis protein 4 (HE4) had been shown to be an ideal biomarker in ovarian cancer. However, there were fewer reports on its application in lung cancer. We explored the diagnostic value of serum HE4 as a biomarker in early lung cancer by comparing it with other biomarkers. METHODS: 162 individuals including 112 cases of lung cancer at early stage and 50 healthy people as controls were enrolled. The serum concentrations of biomarkers were determined with the Roche Elecsys assays. RESULTS: In comparison to the other biomarkers such as carcinoembryonic antigen (CEA), neuron-specific-enolase (NSE), serum cytokeratin 19 fragment (CYFRA 21-1) and progastrinreleasing peptide (proGRP), serum HE4 was one of the biomarkers with the highest sensitivity (43.8%) and specificity (95.0%) for early lung cancer diagnosis. In terms of histological results, serum HE4 was the best biomarker both in adenocarcinoma (AC) and squamous carcinoma (SC), and serum proGRP was the best in small cell lung cancer (SCLC). The combination of proGRP, NSE and HE4 could determine the histological type of lung cancer with a very high accuracy of 93.8%. CONCLUSIONS: These findings suggested that serum HE4 was a better biomarker in early lung cancer than other frequently-used biomarkers.

A glial cell line-derived neurotrophic factor (GDNF):tetanus toxin fragment C protein conjugate improves delivery of GDNF to spinal cord motor neurons in mice.

Glial cell line-derived neurotrophic factor (GDNF) has shown robust neuroprotective and neuroreparative activities in various animal models of Parkinson's Disease or amyotrophic lateral sclerosis (ALS). The successful use of GDNF as a therapeutic in humans, however, appears to have been hindered by its poor bioavailability to target neurons in the central nervous system (CNS). To improve delivery of exogenous GDNF protein to CNS motor neurons, we employed chemical conjugation techniques to link recombinant human GDNF to the neuronal binding fragment of tetanus toxin (tetanus toxin fragment C, or TTC). The predominant species present in the purified conjugate sample, GDNF:TTC, had a molecular weight of approximately 80 kDa as determined by non-reducing SDS-PAGE. Like GDNF, addition of GDNF:TTC to culture media of neuroblastoma cells expressing GFRalpha-1/c-RET produced a dose-dependent increase in cellular phospho-c-RET levels. Treatment of cultured midbrain dopaminergic neurons with either GDNF or the conjugate similarly promoted both DA neuron survival and neurite outgrowth. However, in contrast to mice treated with GDNF by intramuscular injection, mice receiving GDNF:TTC revealed intense GDNF immunostaining associated with spinal cord motor neurons in fixed tissue sections. That GDNF:TTC provided neuroprotection of axotomized motor neurons in neonatal rats further revealed that the conjugate retained its GDNF activity in vivo. These results indicate that TTC can serve as a non-viral vehicle to substantially improve the delivery of functionally active growth factors to motor neurons in the mammalian CNS.

Functional analysis of cold-inducible cDNA clones in the legume Ammopiptanthus mongolicus.

Ammopiptanthus mongolicus is the only evergreen broadleaf shrub endemic to the Alashan desert, northwest sand area of China, and can survive -30 degrees C or an even lower temperature in winter. A modified solid-phase subtraction hybridization technique was developed to isolate and screen cDNAs whose transcripts increased in cold-treated A. mongolicus seedlings. Sequence analysis of the screened clones indicated that 11 clones had coding regions, with four of them containing a complete open reading frame. Nine of the 11 clones shared various degrees of homology with the genes found in the GenBank database and the other two were unidentified sequences. Sequence data further revealed that these accumulated transcripts encoded: three low molecular weight proteins (a late-embryogenesis protein and two cold acclimation responsive proteins); two photosynthesis-related proteins, (photosystem I subunit II precursor (PsaD) and photosystem II oxygen-evolving complex 33kDa subunit OEC33); a protease inhibitor; an adenosine triphosphatase and a 14-3-3 related protein. Analysis of the function of these proteins indicated that the low molecular weight proteins were associated with water holding ability of cytoplasm, photosynthesis-related proteins participated in the adjustments of photosynthetic apparatus to resist photoinhibition; 14-3-3 related protein could interact with adenosine triphosphatase to enhance ATPase activity and energy metabolism, and protease inhibitor is involved in the prevention of unwanted cell death caused by reactive oxygen species. We suggest that cold acclimation with low light intensity in A. mongolicus is a more complex interaction of low temperature, light, energy and signal than that assumed previously.

[Prognostic factors in patients with stage III and IV non-small cell lung cancer].

OBJECTIVE: To investigate the prognostic factors in non-small cell lung cancer (NSCLC) at stage III and IV and establish a reliable model of clinical prognostic index. METHODS: Kaplan-Meier and Cox regression were used to analyze the relationship between the prognostic factors and survival time in 114 cases of NSCLC. The prognostic factors included clinical-pathological features and serum levels of cytokeratin fragment 19 (Cyfra21-1), CEA, neuron-specific enolase (NSE), CA125, interleukin-2 (IL-2) and soluble interleukin-2 receptors (sIL-2R). RESULTS: Kaplan-Meier analysis showed that KPS, sex, disease stage, treatment, Cyfra21-1, sIL-2R and CA125 were related to prognosis. Multivariate analysis indicated that Cyfra21-1, stage and treatment were independent prognostic factors. When Cyfra21-1 > 3.5 mg/L, stage IV and chemotherapy < 3 cycles, the relative risk (RR) was 1.691, 2.229 and 3.035, respectively. In patients given 3 or more cycles of chemotherapy, serum Cyfra21-1, sIL-2R and stage at diagnosis were significantly independent prognostic factors. Three of these prognostic factors were used to establish a prognostic index (PI) model based on a simple algorithm: PI = Cyfra21-1 + sIL-2R + stage. The median survival period of patients with 3 or more cycles of chemotherapy were 18 months if PI = 0, 8 months if PI = 1 or 2, and 5 months if PI = 3. CONCLUSION: The serum Cyfra21-1, sIL-2R and disease stage in unresectable NSCLC were independent prognostic factors. PI calculated on the basis of Cyfra21-1, sIL-2R and stage is recommended to predict the survival period of NSCLC.