Potential inhibitors for blocking the interaction of the coronavirus SARS-CoV-2 spike protein and its host cell receptor ACE2

The outbreak of SARS-CoV-2 continues to pose a serious threat to human health and social and economic stability. In this study, we established an anti-coronavirus drug screening platform based on the Homogeneous Time Resolved Fluorescence (HTRF) technology and the interaction between the coronavirus S protein and its host receptor ACE2. This platform is a rapid, sensitive, specific, and high throughput system. With this platform, we screened two compound libraries of 2,864 molecules and identified three potential anti-coronavirus compounds: tannic acid (TA), TS-1276 (anthraquinone), and TS-984 (9-Methoxycanthin-6-one). Our in vitro validation experiments indicated that TS-984 strongly inhibits the interaction of the coronavirus S-protein and the human cell ACE2 receptor. This data suggests that TS-984 is a potent blocker of the interaction between the S-protein and ACE2, which might have the potential to be developed into an effective anti-coronavirus drug. SIGNIFICANCEThe ongoing pandemic of COVID-19 caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made a serious threat to public health worldwide. Given the urgency of the situation, researchers are attempting to repurpose existing drugs for treating COVID-19. In this present study, we screened two compound libraries of 2,864 molecules and identified a potent inhibitor (TS-984) for blocking the coronavirus S-protein and the human cell ACE2 receptor. TS-984 might have the potential to be developed into an effective anti-coronavirus drug for treating COVID-19.

Differentially expressed gene in nasopharyngeal carcinoma cell lines with various metastatic potentialities / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate gene expression profile in nasopharyngeaL carcinoma (NPC) cell lines with different metastatic potentialities, in order to identify new candidate genes related to the development, progress and metastasis of NPC.</p><p><b>METHODS</b>The mRNA expressions of high metastatic NPC cell line 5-8F, tumorigenic but nonmetastatic NPC cell line 6-10B and non-tumorigenic NPC cell line 13-9B (3 sublines of SUNE-1) were investigated by cDNA microarray containing 14 000 cDNA clones. The alterations in gene expression levels were confirmed by reverse-transcription PCR.</p><p><b>RESULTS</b>There were 82 differentially expressed genes comparing 5-8F and 13-9B; 38 differentially expressed genes comparing 6-10B and 13-9B; 54 comparing 5-8F and 6-10B. There were 12 common differentially expressed genes comparing 6-10B, 5-8F and 13-9B; 14 common differentially expressed genes comparing 5-8F and 13-9B, 6-10B. The expressions of the above genes were involved in metabolism, transcription, differentiation, apoptosis and signal transduction.</p><p><b>CONCLUSION</b>The gene expression profile in nasopharyngeal carcinoma cell lines is an important index in the search of new candidate genes related to NPC.</p>

Rapid tissue microarray assay of p16 protein expression for different stage nasopharyngeal carcinoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To effectively screen p16 protein expression of different clinical stage nasopharyngeal carcinoma (NPC) by constructing and applying high-throughput tissue microarray/tissue chip.</p><p><b>METHODS</b>A series of tissue chips were prepared by using tissue arrayer with samples from different clinical stage NPC tumors and noncancerous nasopharynx tissue. Specimens from 259 cases of nasopharyngeal lesions were detected immunohistochemically on a tissue chip for p16 protein expression and the correlation of p16 protein expression to clinical stage of NPC was analyzed statistically.</p><p><b>RESULTS</b>p16 protein expression was detected in all 18 histologically normal nasopharyngeal epithelia. No p16 protein was detected in 3 of 3 (100%) stage I NPC, 38 of 44 (86.3%) stage II NPC, 59 of 68 (86.8%) stage III NPC, 23 of 28 (82.1%) stage IV NPC, 87 of 98 (88.8%) unclear stage NPC. The efficiency of p16 protein expression in NPC tissues was significantly lower than that in normal nasopharyngeal epithelia (chi(2) = 82.58, P < 0.001), and there was no apparent relationship between p16 protein expression and clinical stages (chi(2) = 0.09, P = 0.769).</p><p><b>CONCLUSIONS</b>The frequent deletion of p16 protein in NPC suggests that p16 gene has an important role in the development and progression of NPC. The consistency of p16 protein deletion in different stages of NPC suggests that the deletion of p16 protein is an early event in the development of NPC, and it is feasible to utilize tissue microarray for a rapid, economic and accurate screening of clinical tissue specimens on a large scale.</p>

Deletion of the LMP-1 gene integrated in the nasopharyngeal carcinoma cell line SUNE-1 / 中国病理生理杂志

AIM: To study the EBV LMP-1 gene integrated in the chromosome of poorly differentiated nasopharyngeal carcinoma cell line SUNE-1. METHODS: The LMP-1 gene of SUNE-1 was detected with PCR; Deletion of LMP-1 was examined by restriction endonuclease analysis and PCR. The deletion was precisely localized by DNA sequencing. RESULTS: The LMP-1 gene integrated in the chromosome of SUNE-1 could be deleted or non-deleted. The two introns of LMP-1 gene were shown being lost in SUNE-1 cell line. CONCLUSION: Deletion of intron 1 and intron 2 happen in some of the LMP-1 gene integrated in the chromosome of SUNE-1.

Evidence for high-frequent deletion of p53 gene in primary hepatocellular carcinoma by interphase dual fluorescence in situ hybridization / 中国病理生理杂志

AIM: To investigate the frequency and pattern of deletion of p53 gene in primary hepatocellular carcinoma (HCC) and its clinical significance. METHODS: The interphase dual fluorescence in situ hybridization(FISH) technique was applied to detect loss of p53 gene in HCCs. RESULTS: The deletion of p53 gene was found in 68.0% of HCCs whereas no loss of p53 gene was detected in 40 mated normal liver specimens. Loss of p53 gene was closely related to tumor size and serum ?-fetoprotein(AFP) level in HCC patients ( P 0.05). The 2-year survival rate of postoperative HCC patients was significantly lower in the HCC cases with p53 gene deletion (25.6%) than those without p53 gene loss (69.6%) ( ? 2=11.463, P