SARS-CoV-2 infecting the inner ear results in potential hearing damage at the early stage or prognosis of COVID-19 in rodents

ObjectivesIn order to find out the association between the sensorineural hearing loss and COVID-19, we detected the expression ACE2 and TMPRSS2 in the mouse the hamster. DesignUsing the public data from NCBI and GISAID, we assessed the expression of ACE2 and TMPRSS2 at the transcriptomic, DNA, and protein levels of ACE2 in the brain, inner ear, and muscle from the golden Syrian hamster (Mesocricetus auratus) and mouse (Mus musculus). ResultsWe identified ACE2 and TMPRSS2 expressed at different level in the inner ear and brain at DNA and transcriptomic levels of both mouse and the hamster. The protein expression shows a similar pattern of the brain and inner ear, while the expression of ACE2 from the inner ear was relatively higher than it from the muscle. ConclusionSARS-CoV-2 could infect the hearing system potentially and SSNHL could be a characteristic to detect asymptomatic patients of COVID-19.

A novel viral protein translation mechanism reveals mitochondria as a target for antiviral drug development

The ongoing Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) pandemic has acutely highlighted the need to identify new treatment strategies for viral infections. Here we present a pivotal molecular mechanism of viral protein translation that relies on the mitochondrial translation machinery. We found that rare codons such as Leu-TTA are highly enriched in many viruses, including SARS-CoV-2, and these codons are essential for the regulation of viral protein expression. SARS-CoV-2 controls the translation of its spike gene by hijacking host mitochondria through 5 leader and 3UTR sequences that contain mitochondrial localization signals and activate the EGR1 pathway. Mitochondrial-targeted drugs such as lonidamine and polydatin significantly repress rare codon-driven gene expression and viral replication. This study identifies an unreported viral protein translation mechanism and opens up a novel avenue for developing antiviral drugs. One Sentence SummaryMitochondria are a potential target for antiviral therapy

An effective, safe and cost-effective cell-based chimeric vaccine against SARS-CoV2

More than one hundred vaccines against SARS-CoV-2 have been developed and some of them have entered clinical trials, but the latest results revealed that these vaccines still face great challenges. Here, we developed a novel cell-based gp96-Ig-secreting chimeric vaccine which is composed of two viral antigens, the RBD of spike protein, and a truncated nucleocapsid protein that could induce epitope-specific cytotoxic T lymphocytes but low antibody response. Syrian hamsters immunized with the cell-based vaccine produced high level of SARS-CoV-2 specific NAbs and specific T cell immunity which could eliminate RBD-truncated N-expressing cells, without the induction of antibody against N protein and other observed toxicity. This study provides a proof of concept for clinical testing of this safe, effective and cost-effective vaccine against SARS-CoV2 infection.

Binding Ability Prediction between Spike Protein and Human ACE2 Reveals the Adaptive Strategy of SARS-CoV-2 in Humans

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a novel coronavirus causing an outbreak of COVID-19 globally in the past six months. A relatively higher divergence on the spike protein of SASR-CoV-2 enables it to transmit across species efficiently. We particularly believe that the adaptive mutations of the receptor-binding domain (RBD) of spike protein in SARS-CoV-2 might be essential to its high transmissibility among humans. Thus here we collected 2,142 high-quality genome sequences of SARS-CoV-2 from 160 regions in over 50 countries and reconstructed their phylogeny, and also analyzed the interaction between the polymorphisms of spike protein and human ACE2 (hACE2). Phylogenetic analysis of SARS-CoV-2 and coronavirus in other hosts show SARS-CoV-2 is highly possible originated from Bat-CoV (RaTG13) found in horseshoe bat and a recombination event may occur on the spike protein of Pangolin-CoV to imbue it the ability to infect humans. Moreover, compared to the S gene of SARS-CoV-2, it is more conserved in the direct-binding sites of RBD and we noticed that spike protein of SARS-CoV-2 may under a consensus evolution to adapt to human hosts better. 3,860 amino acid mutations in spike protein RBD (T333-C525) of SARS-CoV-2 were simulated and their stability and affinity binding to hACE2 (S19-D615) were calculated. Our analysis indicates SARS-CoV-2 could infect humans from different populations with no preference, and a higher divergence in the spike protein of SARS-CoV-2 at the early stage of this pandemic may be a good indicator that could show the pathway of SARS-CoV-2 transmitting from the natural reservoir to human beings.

Expression of microtubule actin cross-linking factor 1 in gastric carcinoma and its effect on cell invasion and metastasis / 中华消化杂志

Objective@#To explore the role of microtubule actin cross-linking factor 1(MACF1) in the metastasis of gastric cancer.@*Methods@#From 2009 to 2012, at The First Affiliated Hospital of Zhengzhou University, the paraffin blocks of gastric cancer and normal tissue adjacent to cancer of 107 patients who received radical gastrectomy were collected. The expression of MACF1 in tissues at protein level was detected by immunohistochemical staining. In 2017, at The First Affiliated Hospital of Zhengzhou University, fresh specimens samples of gastric cancer and normal tissue adjacent to cancer of 42 patients who received radical gastrectomy were also collected. The expression of MACF1 at mRNA level was determined by quantitative real-time polymerase chain reaction (PCR). MACF1 knockout gastric cell line was established. The effects of MACF1 on cell migration and invasion were verified by wound-healing test and Transwell assay. The effects of MACF1 on cell microtubule and actin were analyzed by filamentous actin (F-actin) staining. T-test, chi-square test and multivariate analysis were used for statistical analysis.@*Results@#The positive expression rate of MACF1 in gastric carcinoma tissues was 71.0%(76/107), which was significantly higher than that of the corresponding normal tissues adjacent to cancer (22.4%, 24/107), and the difference was significant (t=4.145, P=0.016). The expression of MACF1 at mRNA level in cancer tissues of 42 patients with gastric cancer was 6.463±0.672, which was significantly higher than that of corresponding normal tissue adjacent to cancer (1.727±0.331), and the difference was statistically significant (t=6.326, P<0.01). The differences in positive expression rate of MACF1 in different tumor infiltration depth, different TNM stage and lymph nodes metastasis were statistically significant (χ2=1.170, 7.959 and 5.288; all P<0.01). The five-year survival rate of patients with high expression of MACF1 was 32.9% (25/76), which was significantly lower than that of patients with normal MACF1 expression (64.5%, 20/31), and the difference was statistically significant (χ2=25.093, P=0.034). The high expression of MACF1 was an independent prognostic factor affecting overall survival rate in patients with gastric cancer after surgery(hazard ratio (HR)=0.513, 95%confidence interval (CI): 0.411 to 0.922, P=0.038). The results of wound-healing assay showed that at 24 hour after wound the migration ability of MACF1 knockout AGS- MACF1-/- cells was (18.77±3.82)%, which was lower than that of wild type AGS cells ((76.24±5.36)%), and the difference was statistically significant (t=6.249, P=0.014). The migration ability of MACF1 knockout HGC27-MACF1-/-cells was (42.48±7.37)%, which was lower than that of wild type HGC27 cells ((82.35±4.28)%), and the difference was statistically significant (t=5.938, P=0.017). The results of Transwell assay indicated that the number of migration cells of MACF1 knockout AGS-MACF1-/- cells was 87.0±11.0, which was less than that of wild type AGS cells (200.0±16.0), and the difference was statistically significant (t=5.820, P=0.028). The number of migration cells of MACF1 knockout HGC27-MACF1-/-cells was 151.0±13.0, which was less than that of wild type HGC27 cells (268.5±20.5), and the difference was statistically significant (t=4.840, P=0.040). The results of F-actin staining demonstrated that the number of actin filaments of MACF1 knockout AGS-MACF1-/- cells was 216.60±18.09, which was less than that of wild type AGS cells (491.30±5.02), and the difference was statistically significant (t=14.630, P=0.005).@*Conclusions@#The abnormally high expression of MACF1 in gastric cancer tissues may be correlated with the poor prognosis of patients with gastric cancer. MACF1 promotes the invasion and metastasis of gastric cancer cells by affecting the formation of F-actin and cell skeleton.

Expression of microtubule actin cross-linking factor 1 in gastric carcinoma and its effect on cell invasion and metastasis / 中华消化杂志

Objective To explore the role of microtubule actin cross-linking factor 1 (MACF1) in the metastasis of gastric cancer.Methods From 2009 to 2012,at The First Affiliated Hospital of Zhengzhou University,the paraffin blocks of gastric cancer and normal tissue adjacent to cancer of 107 patients who received radical gastrectomy were collected.The expression of MACF1 in tissues at protein level was detected by immunohistochemical staining.In 2017,at The First Affiliated Hospital of Zhengzhou University,fresh specimens samples of gastric cancer and normal tissue adjacent to cancer of 42 patients who received radical gastrectomy were also collected.The expression of MACF1 at mRNA level was determined by quantitative real-time polymerase chain reaction (PCR).MACF1 knockout gastric cell line was established.The effects of MACF1 on cell migration and invasion were verified by wound-healing test and Transwell assay.The effects of MACF1 on cell microtubule and actin were analyzed by filamentous actin (F-actin) staining.T-test,chi-square test and multivariate analysis were used for statistical analysis.Results The positive expression rate of MACF1 in gastric carcinoma tissues was 71.0％ (76/107),which was significantly higher than that of the corresponding normal tissues adjacent to cancer (22.4％,24/107),and the difference was significant (t =4.145,P =0.016).The expression of MACF1 at mRNA level in cancer tissues of 42 patients with gastric cancer was 6.463 ±0.672,which was significantly higher than that of corresponding normal tissue adjacent to cancer (1.727 ± 0.331),and the difference was statistically significant (t =6.326,P ＜ 0.01).The differences in positive expression rate of MACF1 in different tumor infiltration depth,different TNM stage and lymph nodes metastasis were statistically significant (x2 =1.170,7.959 and 5.288;all P ＜ 0.01).The five-year survival rate of patients with high expression of MACF1 was 32.9％ (25/76),which was significantly lower than that ofpatients with normal MACF1 expression (64.5％,20/31),and the difference was statistically significant (x2 =25.093,P =0.034).The high expression of MACF1 was an independent prognostic factor affecting overall survival rate in patients with gastric cancer after surgery (hazard ratio (HR) =0.513,95％ confidence interval (CI):0.411 to 0.922,P =0.038).The results of wound-healing assay showed that at 24 hour after wound the migration ability of MACF1 knockout AGS-MACF1 / cells was (18.77 ± 3.82) ％,which was lower than that of wild type AGS cells ((76.24 ± 5.36) ％),and the difference was statistically significant (t =6.249,P =0.014).The migration ability of MACF1 knockout HGC27-MACF1-/-cells was (42.48 ± 7.37)％,which was lower than that of wild type HGC27 cells ((82.35-± 4.28) ％),and the difference was statistically significant (t =5.938,P =0.017).The results of Transwell assay indicated that the number of migration cells of MACF1 knockout AGS-MACF1-/-cells was 87.0 ± 11.0,which was less than that of wild type AGS cells (200.0 ± 16.0),and the difference was statistically significant (t =5.820,P =0.028).The number of migration cells of MACF1 knockout HGC27-MACF1-/-cells was 151.0 ± 13.0,which was less than that of wild type HGC27 cells (268.5 ± 20.5),and the difference was statistically significant (t =4.840,P =0.040).The results of F-actin staining demonstrated that the number of actin filaments of MACF1 knockout AGS-MACF1-/-cells was 216.60 ± 18.09,which was less than that of wild type AGS cells (491.30 ± 5.02),and the difference was statistically significant (t =14.630,P =0.005).Conclusions The abnormally high expression of MACF1 in gastric cancer tissues may be correlated with the poor prognosis of patients with gastric cancer.MACF1 promotes the invasion and metastasis of gastric cancer cells by affecting the formation of F-actin and cell skeleton.

Enhancement of CEA specific RNAi on gene engineering adenovirus H101 for treatment of tumor tissue of nude mice transplanted with human esophageal cancer cells / 基础医学与临床

Objective To study the effect of gene engineering adenovirus H101 for treating esophagus carcinoma EC9706 induced by CEA gene specific silencing and to explore internal influential factor of H101 sensitivity. Methods To construct the siRNA expression vector of CEA and to inhibit the expression of CEA through RNA interference and gene transfection in EC9706 cell,stable CEA gene silencing system was set up,compared with empty vector group and non-transfected EC9706 cell,the model of athymic mouse subcutaneous transplantation tumor of human esophagus carcinoma EC9706 cell was established followed by injection with H101. The mRNA and protein expressions of CEA were detected by real time PCR and immunohistochemistry,the tumor size was measured. Results Silencing CEA gene by applying RNAi can inhibit CEA mRNA and protein expression in nude mice model with transplanted human esophageal cancer cells,there was no evident influence on tumor growth and mass oftumor. After using H101,the tumor size of interfering group was much smaller than that of empty vector group and normal control group(P