Structure-based approaches against COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has had a major impact on human life. This review highlights the versatile roles of both classical and modern structure-based approaches for COVID-19. X-ray crystallography, nuclear magnetic resonance spectroscopy, and cryogenic electron microscopy are the three cornerstones of classical structural biology. These technologies have helped provide fundamental and detailed knowledge regarding severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the related human host proteins as well as enabled the identification of its target sites, facilitating the cessation of its transmission. Further progress into protein structure modeling was made using modern structure-based approaches derived from homology modeling and integrated with artificial intelligence (AI), facilitating advanced computational simulation tools to actively guide the design of new vaccines and the development of anti-SARS-CoV-2 drugs. This review presents the practical contributions and future directions of structure-based approaches for COVID-19.

A multiomic investigation of lung adenocarcinoma molecular subtypes

BACKGROUND

Lung adenocarcinoma-an aggressive and life-threatening malignancy-is a type of non-small-cell lung cancer. Despite medical advancements, the prognosis of lung adenocarcinoma remains unfavorable, likely because of its heterogeneous nature. Furthermore, few subtype-specific treatments are available for lung adenocarcinoma. This study was conducted to explore the molecular subtypes of lung adenocarcinoma.

METHODS

We performed a joint analysis of transcriptome and proteome data from East Asian patients with lung adenocarcinoma (nonsmokers, 86.5%).

RESULTS

Four novel subtypes were identified based on distinct molecular characteristics: subtypes I, II, III, and IV. In patients with subtype I lung adenocarcinoma, eukaryotic translation initiation factor 4 gamma 1 activates cell proliferation; inhibiting this factor suppresses tumor growth, and reducing its level induces autophagy. Subtype II is characterized by Kristen rat sarcoma viral oncogene homolog-activating oncogenesis; the onset age of this subtype is the lowest among all subtypes. Subtype III manifests as an advanced disease at diagnosis; it is characterized by a core serum response-related oncogenic signature, which indicates poor overall survival in Western patients with lung cancer. Subtype IV is more common in men than in women; it has astroglial characteristics. A Connectivity Map analysis revealed that the oncogenic expression patterns corresponding to subtypes I, II, III, and IV can be reversed by the inhibitors of Inhibitor of κB (IκB) kinase (eg, withaferin A), mammalian target of rapamycin (eg, everolimus), Src proto-oncogene (Src) (eg, saracatinib), and Transforming Growth Factor (TGF)-β/Smad (eg, LY-364947), respectively.

CONCLUSION

This study introduced an innovative multiomics data analysis pipeline. Using this approach, we successfully identified four molecular subtypes of lung adenocarcinoma and their candidate therapeutic agents. The newly identified subtypes can be combined with the current biomarkers to generate a comprehensive roadmap for treatment decision-making.

[Analysis of MRI features of hepatocyte nuclear factor 1α-inactivated hepatocellular adenoma]

Objective: To investigate the MRI imaging features of hepatocyte nuclear factor 1α- inactivated hepatocellular adenoma (H-HCA). Methods: Clinical data and MRI images of 19 H-HCA cases who were pathologically confirmed at Zhongshan Hospital Affiliated to Fudan University between August 2014 and July 2020 were retrospectively analyzed. Among them, there were 15 females and 4 males, aged 16-47 (32± 7) years old. Tumor number, location, shape, size, boundary, MRI plain scan signal intensity, dynamic enhancement features of each phase, presence or absence of intratumoral fat content, pseudocapsule, and others were analyzed. The differences in apparent diffusion coefficient (ADC) values between the lesion and the surrounding normal liver parenchyma were compared for statistical significance. t-test was used for statistical analysis. Results: There were a total of 24 lesions in 19 cases. 14 cases had solitary lesions, and five cases had multiple lesions. 15 and nine lesions were located in the right and left lobes of the liver, respectively. 20 lesions were round or quasi-round, and four were irregular or lobulated. The tumor's maximal diameter was 0.6-8.6 (3.5 ± 2.4) cm. T(1)-weighted image (WI) showed hyperintense to iso-intense signals in 20 lesions and hypointense signals in four. T(2)WI showed iso-to-slightly high signal intensity in 16 lesions, with two hyperintense and six hypointense signals. Diffusion-weighted image (DWI) revealed hyperintense to iso-intense signals. Lesions mean ADC value was (1.289 ± 0.222)×10(-3) mm(2)/s, while the adjacent normal liver parenchyma's mean ADC value was (1.307 ± 0.236)×10(-3) mm(2)/s, with no statistically significant difference between the two (P > 0.05). During the arterial phase, 15 of the 18 lesions that underwent dynamic contrast-enhanced scanning with gadoxetate disodium (Gd-DTPA) were mildly to moderately enhanced and three were strongly enhanced. The portal and hepatic venous phases had no continuous enhancement, while the delayed phase showed a hypointense signal. During the arterial phase, two of the six lesions scanned by gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid ((Gd-EOB-DTPA) dynamic enhancement were mildly to moderately enhanced, while four were strongly enhanced. The portal and hepatic venous phases had no continuous enhancement, while the transition and hepatobiliary-specific phases showed hypointense signals. Intracellular steatosis occurred in 21 lesions, of which 19 were diffuse steatosis and 16 formed pseudocapsules in the delayed phase. Conclusion: H-HCA often occurs in young females as solitary lesions and has certain MRI features. T1WI anti-phase diffuse signal reduction and post-enhanced hypovascular withdrawal enhancement patterns can aid in accurately diagnosing the disease condition.

Circular RNA ZNF800 (hsa_circ_0082096) regulates cancer stem cell properties and tumor growth in colorectal cancer

BACKGROUND

Cancer stem cells form a rare cell population in tumors that contributes to metastasis, recurrence and chemoresistance in cancer patients. Circular RNAs (circRNAs) are post-transcriptional regulators of gene expression that sponge targeted microRNA (miRNAs) to affect a multitude of downstream cellular processes. We previously showed in an expression profiling study that circZNF800 (hsa_circ_0082096) was up-regulated in cancer stem cell-enriched spheroids derived from colorectal cancer (CRC) cell lines.

METHODS

Spheroids were generated in suspension spheroidal culture. The ZNF800 mRNA, pluripotency stem cell markers and circZNF800 levels were determined by quantitative RT-PCR. CircZNF800-miRNA interactions were shown in RNA pulldown assays and the miRNA levels determined by stem-loop qRT-PCR. The effects of circZNF800 on cell proliferation were tested by EdU staining followed by flowcytometry. Expression of stem cell markers CD44/CD133, Lgr5 and SOX9 was demonstrated in immunofluorescence microscopy. To manipulate the cellular levels of circZNF800, circZNF800 over-expression was achieved via transfection of in vitro synthesized and circularized circZNF800, and knockdown attained using a CRISPR-Cas13d-circZNF800 vector system. Xenografted nude mice were used to demonstrate effects of circZNF800 over-expression and knockdown on tumor growth in vivo.

RESULTS

CircZNF800 was shown to be over-expressed in late-stage tumor tissues of CRC patients. Data showed that circZNF800 impeded expression of miR-140-3p, miR-382-5p and miR-579-3p while promoted the mRNA levels of ALK/ACVR1C, FZD3 and WNT5A targeted by the miRNAs, as supported by alignments of seed sequences between the circZNF800-miRNA, and miRNA-mRNA paired interactions. Analysis in CRC cells and biopsied tissues showed that circZNF800 positively regulated the expression of intestinal stem cell, pluripotency and cancer stem cell markers, and promoted CRC cell proliferation, spheroid and colony formation in vitro, all of which are cancer stem cell properties. In xenografted mice, circZNF800 over-expression promoted tumor growth, while circZNF800 knockdown via administration of CRISPR Cas13d-circZNF800 viral particles at the CRC tumor sites impeded tumor growth.

CONCLUSIONS

CircZNF800 is an oncogenic factor that regulate cancer stem cell properties to lead colorectal tumorigenesis, and may be used as a predictive marker for tumor progression and the CRISPR Cas13d-circZNF800 knockdown strategy for therapeutic intervention of colorectal cancer.

[Application of intraoperative optical coherence tomography in deep lamellar keratoplasty]

Objective: To evaluate the clinical application value of intraoperative optical coherence tomography (iOCT) in deep anterior lamellar keratoplasty (DALK) using the big-bubble technique to bare Descemet's membrane. Methods: Retrospective case series. Clinical data of 92 patients (92 eyes) with monocular stromal corneal diseases who underwent big-bubble DALK in the Eye Hospital of Shandong First Medical University from January 2020 to August 2021 were collected. There were 53 males and 39 females. The average age was (53.2±16.0) years old. All patients underwent iOCT scanning to determine the location and depth of the injection needle after initial removal of the corneal lesion, to observe the integrity of the recipient bed, Descemet's membrane, after complete lesion removal, and to observe the adhesion between the corneal graft and the recipient bed and check folds on the recipient bed after suturing of the corneal graft. The intraoperative perforation of Descemet's membrane, postoperative thickness of the cornea and the recipient bed, visual acuity, and corneal astigmatism were recorded. Results: By iOCT, the thickness of the recipient bed was found to be about 1/2 of the corneal thickness and relatively uniform in all directions in 62 eyes (67.4%), so the sterile air was injected from the center of the recipient bed to separate it from the stromal layer. In 30 eyes (32.6%) with an uneven thickness of the recipient bed, the sterile air was injected from the paracentral area of the recipient bed. Under the guidance of iOCT scanning, 89 eyes (96.7%) did not experience any perforation of Descemet's membrane during surgery. The Descemet's membrane folds in the central 5-mm area of the recipient bed was observed and flattened in 20 eyes with the assistance of iOCT scanning. The postoperative corneal thickness was (578.95±108.26) μm, and the recipient bed thickness was (36.06±23.11) μm. The best corrected visual acuity of all patients at 6 months after surgery was 0.57±0.25 logMAR, which was significantly better than that before surgery (1.61±1.27 logMAR; P<0.001). The average corneal astigmatism at 6 months after surgery was (2.72±2.44) diopters. Conclusions: The application of iOCT scanning in DALK surgery assisted by the big-bubble method can provide safe guidance for surgeons to adopt correct surgical procedures, decrease the risk of Descemet's membrane perforation, reduce the recipient bed folds, and facilitate corneal interlayer adhesion, thereby improving the visual prognosis.

[Mechanism of piRNA in bisphenol A-promoted invasion and migration of prostate cancer cells]

Objective: To investigate the regulatory mechanisms of piwi-interacting RNA (piRNA) in bisphenol A (BPA)-induced prostate cancer cell invasion and migration. Methods: The Cancer Genome Atlas (TCGA) data was used to analyze and screen for piRNAs with significantly increased expression in prostate cancer tissues. PC-3 cells were treated with different concentrations of BPA for 12, 24, and 48 h, respectively, and the 20% inhibitory concentration (IC20) was measured using a CCK-8 assay. The expression levels of piRNAs before and after BPA treatment were determined by reverse transcription-quantitative PCR. Target genes regulated by BPA and associated with prostate cancer were screened in the Comparative Toxicogenomics Database (CTD). Dual-luciferase reporter gene assay was performed to verify the relationship between piRNA and target genes, and the expression change of the piRNA target gene was detected by Western blotting. Cell migration and invasion assays were used to determine the effects of piRNA on the malignant phenotype of prostate cancer cells. Results: After treatment of PC-3 cells with 160 μmol/L BPA, the expression of piR-sno48 was most significantly increased (P<0.05). Transfection of piR-sno48 antagomir resulted in decreased expression of endogenous piR-sno48 and a significant increase in the expression of its target gene GSTP1 (P<0.05). However, the expression of GSTP1 did not change significantly in BPA-treated PC-3 cells after transfection with piR-sno48 antagomir (P>0.05). The dual-luciferase reporter gene confirmed that piR-sno48 inhibited the expression of GSTP1 by forming an inversely complementary sequence with the 3'-UTR of GSTP1. The Transwell assay results showed that treatment with BPA significantly increased the invasion and migration ability of prostate cancer cells (P<0.01), whereas piR-sno48 antagonists significantly inhibited the effects above (P<0.01). Conclusion: BPA promotes the invasion and migration of prostate cancer cells by upregulating the expression of piR-sno48 and suppressing the expression of GSTP1. Interfering with the expression of endogenous piR-sno48 may inhibit the malignant phenotype of prostate cancer cells caused by BPA.

[Application of synthetic MRI in predicting isocitrate dehydrogenase 1 genotypes in gliomas]

This study analyzed the clinical and imaging data of 81 glioma patients who underwent brain synthetic MRI and diffusion weighted imaging (DWI) examination in the General Hospital of Ningxia Medical University from August 2020 to September 2021 to explore the value of synthetic MRI relaxation quantitative value in predicting the genotype of isocitrate dehydrogenase 1 (IDH1) in gliomas. There were 44 males and 37 females, those patients with an aged 50.0 (36.5, 59.0) years. The tumor pre-T1, pre-T2, pre-PD, post-T1 and ADC values were obtained by outlining the region of interest (ROI). Univariate analysis was used to compare the differences of parameter values between groups, and the receiver operating characteristic was used to evaluate the diagnostic efficacy of each parameter value in predicting glioma IDH1 genotype. The results showed that the pre-T1 and pre-PD values [M (Q1, Q3)] of IDH1m glioma were lower than those of IDH1w glioma [1 462.75 (1 306.41, 1 567.75) ms vs 1 532.83 (1 434.67, 1 617.67) ms, 84.18 (82.28, 86.41) pu vs 85.85 (84.65, 86.90) pu] (all P<0.05). The post-T1 and ADC values of IDH1m glioma were higher than those of IDH1w glioma [1 054.50 (631.92, 1 262.63) ms vs 669.67 (535.17, 823.33) ms, 1.20 (0.86, 1.35) ×10-3 mm2/s vs 0.80 (0.76, 0.93) ×10-3 mm2/s] (all P<0.05). The AUC of the combined model (pre-T1+pre-PD+post-T1+ADC+Age) is 0.828 (95%CI:0.729-0.903). Synthetic MRI relaxation quantitative values are helpful to distinguish IDH1 genotypes in glioma. The diagnostic efficacy of the multi-parameter combined model based on pre-T1, pre-PD, post-T1, ADC, and age is better than that of the single parameter, and it can be used as an effective strategy to improve the differential diagnosis ability of gliomas molecular markers.

Modifications of lipid pathways restrict SARS-CoV-2 propagation in human induced pluripotent stem cell-derived 3D airway organoids

BACKGROUND

Modifications of lipid metabolism were closely associated with the manifestations and prognosis of coronavirus disease of 2019 (COVID-19). Pre-existing metabolic conditions exacerbated the severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection while modulations of aberrant lipid metabolisms alleviated the manifestations. To elucidate the underlying mechanisms, an experimental platform that reproduces human respiratory physiology is required.

METHODS

Here we generated induced pluripotent stem cell-derived airway organoids (iPSC-AOs) that resemble the human native airway. Single-cell sequencing (ScRNAseq) and microscopic examination verified the cellular heterogeneity and microstructures of iPSC-AOs, respectively. We subjected iPSC-AOs to SARS-CoV-2 infection and investigated the treatment effect of lipid modifiers statin drugs on viral pathogenesis, gene expression, and the intracellular trafficking of the SARS-CoV-2 entry receptor angiotensin-converting enzyme-2 (ACE-2).

RESULTS

In SARS-CoV-2-infected iPSC-AOs, immunofluorescence staining detected the SARS-CoV-2 spike (S) and nucleocapsid (N) proteins and bioinformatics analysis further showed the aberrant enrichment of lipid-associated pathways. In addition, SARS-CoV-2 hijacked the host RNA replication machinery and generated the new isoforms of a high-density lipoprotein constituent apolipoprotein A1 (APOA1) and the virus-scavenging protein deleted in malignant brain tumors 1 (DMBT1). Manipulating lipid homeostasis using cholesterol-lowering drugs (e.g. Statins) relocated the viral entry receptor angiotensin-converting enzyme-2 (ACE-2) and decreased N protein expression, leading to the reduction of SARS-CoV-2 entry and replication. The same lipid modifications suppressed the entry of luciferase-expressing SARS-CoV-2 pseudoviruses containing the S proteins derived from different SARS-CoV-2 variants, i.e. wild-type, alpha, delta, and omicron.

CONCLUSIONS

Together, our data demonstrated that modifications of lipid pathways restrict SARS-CoV-2 propagation in the iPSC-AOs, which the inhibition is speculated through the translocation of ACE2 from the cell membrane to the cytosol. Considering the highly frequent mutation and generation of SARS-CoV-2 variants, targeting host metabolisms of cholesterol or other lipids may represent an alternative approach against SARS-CoV-2 infection.

[Analysis of the relationship between MRI imaging characteristics and clinical symptoms and therapeutic efficacy in adenomyosis patients]

Objective: To investigate the relationship between magnetic resonance imaging (MRI) imaging characteristics and clinical symptoms and therapeutic efficacy in adenomyosis patients. Methods: The clinical characteristics of the adenomyosis questionnaire was self-designed. This was a retrospective study. From September 2015 to September 2020, totally 459 patients were diagnosed with adenomyosis and underwent pelvic MRI examination at Peking University Third Hospital. Clinical characteristics and treatment were collected, MRI was used to determine the lesion location, and to measure the maximum lesion thickness, the maximum myometrium thickness, uterine cavity length, uterine volume, the minimum distance between the lesion and serosa or endometrium, and whether combined with ovarian endometrioma. The difference of MRI imaging characteristics in patients with adenomyosis and its relationship with clinical symptoms and therapeutic efficacy were analyzed. Results: (1) Among the 459 patients, the age was (39.1±6.4) years. There were 376 patients (81.9%, 376/459) with dysmenorrhea. Whether patients had dysmenorrhea were related to uterine cavity length, uterine volume, ratio of the maximum lesion thickness to the maximum myometrium thickness, and whether patients had ovarian endometrioma (all P<0.001). Multivariate analysis suggested that ovarian endometrioma was the risk factor for dysmenorrhea (OR=0.438, 95%CI: 0.226-0.850, P=0.015). There were 195 patients (42.5%, 195/459) with menorrhagia. Whether patients had menorrhagia were related to age, whether patients had ovarian endometrioma, uterine cavity length, the minimum distance between lesion and endometrium or serosa, uterine volume, ratio of the maximum lesion thickness to the maximum myometrium thickness (all P<0.001). Multivariate analysis suggested that ratio of the maximum lesion thickness to the maximum myometrium thickness was the risk factor for menorrhagia (OR=774.791, 95%CI: 3.500-1.715×10⁵, P=0.016). There were 145 patients (31.6%, 145/459) with infertility. Whether the patients had infertility were related to age, the minimum distance between lesion and endometrium or serosa, and whether patients had ovarian endometrioma (all P<0.01). Multivariate analysis suggested that young and large uterine volume were risk factors for infertility (OR=0.845, 95%CI: 0.809-0.882, P<0.001; OR=1.001, 95%CI: 1.000-1.002, P=0.009). (2) The success rate of in vitro fertilization-embryo transfer (IVF-ET) was 39.2% (20/51). Dysmenorrhea, high maximum visual analogue scale score and large uterine volume affected the success rate of IVF-ET (all P<0.05). The smaller the maximum lesion thickness, the smaller the distance between the lesion and serosa, the larger the distance between the lesion and endometrium, the smaller the uterine volume, and the smaller the ratio of the maximum lesion thickness to the maximum myometrium thickness, the better the therapeutic efficacy of progesterones (all P<0.05). Conclusions: Concomitant ovarian endometrioma increases the risk of dysmenorrhea in patients with adenomyosis. The ratio of the maximum lesion thickness to the maximum myometrium thickness is an independent risk factor for menorrhagia. Young and large uterine volume may increase the risk of infertility. Severe dysmenorrhea and large uterine volume affect the success rate of IVF-ET. The therapeutic efficacy of progesterones is relatively better when the lesion is small and far away from the endometrium.

Current developments and therapeutic potentials of exosomes from induced pluripotent stem cells-derived mesenchymal stem cells

Mesenchymal stem cells (MSCs) are multipotent cells derived from adult human tissues that have the ability to proliferate in vitro and maintain their multipotency, making them attractive cell sources for regenerative medicine. However, MSCs reportedly show limited proliferative capacity with inconsistent therapeutic outcomes due to their heterogeneous nature. On the other hand, induced pluripotent stem cells (iPSC) have emerged as an alternative source for the production of various specialized cell types via their ability to differentiate from all three primary germ layers, leading to applications in regenerative medicine, disease modeling, and drug therapy. Notably, iPSCs can differentiate into MSCs in monolayer, commonly referred to as induced mesenchymal stem cells (iMSCs). These cells show superior therapeutic qualities compared with adult MSCs as the applications of the latter are restricted by passage number and autoimmune rejection when applied in tissue regeneration trials. Furthermore, increasing evidence shows that the therapeutic properties of stem cells are a consequence of the paracrine effects mediated by their secretome such as from exosomes, a type of extracellular vesicle secreted by most cell types. Several studies that investigated the potential of exosomes in regenerative medicine and therapy have revealed promising results. Therefore, this review focuses on the recent findings of exosomes secreted from iMSCs as a potential noncell-based therapy.

Is N -acetylcysteine effective in treating patients with coronavirus disease 2019? A meta-analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a global pandemic caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). It has brought tremendous challenges to public health and medical systems around the world. The current strategy for drug repurposing has accumulated some evidence on the use of N -acetylcysteine (NAC) in treating patients with COVID-19. However, the evidence remains debated.

METHODS

We performed the systematic review and meta-analysis that complies with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Five databases and reference lists were searched from inception to May 14, 2022. Studies evaluating the efficacy of NAC in treating patients with COVID-19 were regarded as eligible. The review was registered prospectively on PROSPERO (CRD42022332791).

RESULTS

Of 778 records identified from the preliminary search, four studies were enrolled in the final qualitative review and quantitative meta-analysis. A total of 355 patients were allocated into the NAC group and the control group. The evaluated outcomes included intubation rate, improvement, duration of intensive unit stay and hospital stay and mortality. The pooled results showed nonsignificant differences in intubation rate (OR, 0.55; 95% CI, 0.16-1.89; p = 0.34; I2 = 75%), improvement of oxygenation ([MD], 80.84; 95% CI, -38.16 to 199.84; p = 0.18; I2 = 98%), ICU stay (MD, -0.74; 95% CI, -3.19 to 1.71; p = 0.55; I2 = 95%), hospital stay (MD, -1.05; 95% CI, -3.02 to 0.92; p = 0.30; I2 = 90%), and mortality (OR, 0.58; 95% CI, 0.23-1.45; p = 0.24; I2 = 54%). Subsequent trial sequential analysis (TSA) showed conclusive nonsignificant results for mortality, while the TSA for the other outcomes suggested that a larger sample size is essential.

CONCLUSIONS

The current evidence reveals NAC is not beneficial for treating patients with COVID- 19 with regard to respiratory outcome, mortality, duration of ICU stay and hospital stay.

Smart healthcare: A prospective future medical approach for COVID-19

COVID-19 has greatly affected human life for over 3 years. In this review, we focus on smart healthcare solutions that address major requirements for coping with the COVID-19 pandemic, including (1) the continuous monitoring of severe acute respiratory syndrome coronavirus 2, (2) patient stratification with distinct short-term outcomes (eg, mild or severe diseases) and long-term outcomes (eg, long COVID), and (3) adherence to medication and treatments for patients with COVID-19. Smart healthcare often utilizes medical artificial intelligence (AI) and cloud computing and integrates cutting-edge biological and optoelectronic techniques. These are valuable technologies for addressing the unmet needs in the management of COVID. By leveraging deep learning/machine learning capabilities and big data, medical AI can perform precise prognosis predictions and provide reliable suggestions for physicians' decision-making. Through the assistance of the Internet of Medical Things, which encompasses wearable devices, smartphone apps, internet-based drug delivery systems, and telemedicine technologies, the status of mild cases can be continuously monitored and medications provided at home without the need for hospital care. In cases that develop into severe cases, emergency feedback can be provided through the hospital for rapid treatment. Smart healthcare can possibly prevent the development of severe COVID-19 cases and therefore lower the burden on intensive care units.

The Omicron variant wave: Where are we now and what are the prospects?

The Omicron variant BA.2 is the dominant form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in many countries, including those that have already implemented the strictest quarantine mandates that effectively contained the spread of the previous variants. Although many individuals were partially or fully vaccinated, confirmed Omicron infections have far surpassed all other variants combined in just a couple of months since the Omicron variant emerged. The ChAdOx1-S (AstraZeneca), BNT162b2 (Pfizer-BioNTech), and mRNA-1273 (Moderna) vaccines offer protection against the severe illness of SARS-CoV-2 infection; however, these currently available vaccines are less effective in terms of preventing Omicron infections. As a result, a booster dose of BNT162b2 or mRNA-1273 is recommended for individuals >12 years old who had received their second dose of the approved vaccines for >5 months. Herein, we review the studies that assessed the clinical benefits of the booster dose of vaccines against Omicron infections. We also analyzed public data to address whether early booster vaccination effectively prevented the surge of the Omicron infections. Finally, we discuss the consideration of a fourth dose of vaccine as a way to prevent possible upcoming infections.

[Impact of treatment compliance in chronic hepatitis B]

The incidence rate of chronic hepatitis B remains high in China. Antiviral therapy can significantly reduce the risk of progressive liver disease and hepatocellular carcinoma in patients with chronic hepatitis B. However, all current antiviral treatments can only inhibit HBV replication and not completely eliminate the hepatitis B virus, so antiviral therapy for chronic hepatitis B is probably a long-term or even lifelong treatment. Antiviral therapy compliance is essential for achieving long-term clinical benefits and preventing nucleot(s)ide drugs resistance. Herein, we analyzed the relevant factors of antiviral therapy compliance and their impact on CHB treatment and explored feasible programs that can improve compliance with nucleot(s)ide drug treatment by conducting a literature search using PubMed and Scopus with search terms including hepatitis B, compliance, nucleot(s)ide drugs, antiviral therapy, viral suppression, and drug resistance.

[MRI features of lymphoepithelioma-like intrahepatic cholangiocarcinoma]

Objective: To investigate the MRI manifestations of lymphoepithelioma-like intrahep cholangiocarcinoma (LEL-ICC). Methods: MR images of 26 cases with LEL-ICC confirmed pathologically at Zhongshan Hospital Affiliated with Fudan University between March 2011 and March 2021 were retrospectively analyzed. The number, location, size, morphology, edges of lesions, non-scan signal intensity, cystic necrosis, enhancement mode, peak, and capsule, vascular invasion, lymph node metastasis, and other MR images were included for analysis. The apparent diffusion coefficient (ADC) value of the lesion and the surrounding normal liver parenchyma were measured. A paired-sample t-test was used to statistically analyze the measurement data. Results: All 26 cases of LEL-ICC had solitary lesions. Mass-type LEL-ICC was the most common [n=23, lesion size (4.02±2.32) cm] with distribution along the bile duct [n=3, lesion size (7.23±1.40 cm)]. Among the 23 lesions of mass type LEL-ICC, most of the lesions were close to the liver capsule (n=20), round (n=22), clearly bordered (n=13), and cystic necrosis (n=22). In the three lesions of LEL-ICC distributed along the bile duct, most of them were close to the liver capsule (n=2), irregular (n=3), blurred edges (n=3), and cystic necrosis (n=3). All 26 lesions showed a low/slightly low signal on T₁WI, a high/slightly high signal on T₂WI, and a slightly high or high signal on DWI. Three lesions showed fast-in and fast-out enhancement modes, and 23 lesions showed continuous enhancement. Twenty-five lesions showed peak enhancement in the arterial phase, and one lesion appeared in the delayed phase. The ADC value of 26 lesions and adjacent normal liver parenchyma was (1.112±0.274)×10^-3 mm²/s and (1.482±0.346)×10^-3 mm²/s, respectively, and the both had a statistically significant difference (P<0.05). Conclusion: Certain manifestations of LEL-ICC in magnetic resonance imaging are advantageous for diagnosis and differential diagnosis.

[Human chorionic gonadotropin-secreting gonadoblastomas in a girl of 45, X Turner syndrome: a case report and literature review]

Objective: To summarize the experience in diagnosis and treatment of 45, X Turner syndrome (TS) with gonadal Y chromosome mosaicism and bilateral gonadoblastoma (Gb) secreting human chorionic gonadotrophin(HCG). Methods: A female patient aged 5 years and 3 months was admitted to the hospital with a complaint of "enlarged breasts for 27 months, and elevated blood β-HCG for 8 months". The clinical data were summarized, and related literature up to March 2022 with the key words"Turner syndrome" "Gonadoblastoma" "Y chromosome" "human chorionic gonadotropin" "precocious" in PubMed, CNKI and Wanfang databases were reviewed. Results: The girl went to the local hospital for 2-month breast development at age of 3 years, and was found with a heart murmur diagnosed with "pulmonary venous malformation and atrial septal defect (secondary foramen type)". Surgical correction was performed. She experienced the progressive breast development, rapid linear growth and markedly advanced skeletal age, which cannot be explained by partial activation in the hypothalamic-pituitary-gonadal axis determined at the age of 3 years and 7 months in local hospital. Then whole-exome sequencing revealed chromosome number abnormality 45, X, which was confirmed by Karyotyping. At the age of 4 years and 6 months, serum β-HCG was found to be elevated (24.9 U/L) with no lesion found at the local hospital. On physical examination, she was found with breast development, pubic hair development and clitoromegaly with elevated serum testosterone (1.96 μg/L) and β-HCG (32.3 U/L). Sex determining region Y(SRY) gene was negative in peripheral blood sample. Thoracic and abdominal CT, head and pelvic magnetic resonance imaging were normal. Exploratory laparotomy confirmed the presence of a left adnexal tumor and a right fibrous streak gonad. During surgery, simultaneous samples of bilateral gonadal and peripheral venous blood were obtained and serum β-HCG, estradiol and testosteron concentrations was higher to lower from left gonadal venous blood, right gonadal venous blood, to peripheral venous blood. Bilateral gonadectomy was performed. Histopathology revealed bilateral gonadoblastomas. SRY was positive in bilateral gonadal tissues. After surgery, serum E₂, testerone and β-HCG returned to normal. So far 4 cases of HCG-secreting gonadoblastoma had been reported worldwide. The phenotypes of the 4 cases were all female, with virilization or amenorrhea, and the preoperative peripheral blood β-HCG concentrations were 74.4, 5.0, 40 456.0, and 42.4 U/L, respectively. Conclusions: There is a high risk of Gb in TS with Y chromosome components. Gb is infrequently presented with breast development, and Gb associated with HCG secretion is rare. Karyotyping should be performed in a phenotypic female with masculinization, and virilization in TS indicates the presence of Y chromosome material with concurrent androgen secreting tumors.

[A study on the burden of myocarditis in China in 1990 and 2019]

Objective: To investigate Chinese myocarditis burden and trends in 1990 and 2019. Methods: Based on the Global Burden of Disease (GBD) 2019 data, the number of patients, the number of new cases, the number of deaths, the disability-adjusted life years (DALYs), as well as the morbidity, mortality, DALYs rate and their age-standardized rates were used to analyze the trend and the burden of myocarditis in the Chinese population in 1990 and 2019. Results: In 2019, the number of patients, the number of new cases and the number of deaths with myocarditis in China were 234 900, 275 100 and 13 100 respectively, increasing by 85.62%, 47.51% and 50.22% compared with 1990. The age-standardized incidence and mortality were 16.94/100 000 and 0.92/100 000, respectively. Compared with 1990, the age-standardized incidence in 2019 decreased by 6.06%, and the mortality decreased by 16.04% respectively. The age-standardized incidence and mortality of Chinese male patients with myocarditis were higher than that of female. Compared with 1990, the age group with the largest incidence and mortality of myocarditis in China in 2019 all shifted to the elder group. And, DALYs and age-normalized DALYs due to myocarditis in China showed a decreasing trend in 2019, from 458 600 and 42.51/100 000 in 1990 to 341 300 and 25.39/100 000 in 2019, respectively. The rate of DALYs and age-standardized DALYs in male patients was always higher than female. Conclusions: Compared with 1990, the overall burden of myocarditis in China showed a downward trend in 2019, and the burden of myocarditis in male patients was higher than female. More attention should be paid to the burden of myocarditis in Chinese elderly population.

[Keratoconus after transepithelial photorefractive keratectomy: a case report]

A 24-year-old male was treated with transepithelial photorefractive keratectomy for myopia in both eyes 5 years ago. He had allergic conjunctivitis for 3 years. The night vision of both eyes was decreased for 2 years. The clinical diagnosis was keratoconus binoculus. Therefore, corneal collagen cross-linking was performed in both eyes, and the follow-up was 6 months. Confocal microscopy showed that the cross-linking of riboflavin and fiber amino was successful, and the keratoconus did not progress during the follow-up. Although there have been few case reports of keratoconus after transepithelial photorefractive keratectomy at home and abroad, great importance should be attached to the early and comprehensive screening of keratoconus in the candidates of refractive surgery in order to improve the long-term safety.

SARS-CoV-2 vaccines in children and adolescents: Can immunization prevent hospitalization?

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants of concern can infect people of all ages and can cause severe diseases in children, such as encephalitis, which require intensive care. Therefore, vaccines are urgently required to prevent severe disease in all age groups. We reviewed the safety and efficacy profiles of mRNA vaccines-BNT162b2 and mRNA-1273-demonstrated by clinical trials or observed in the real world. mRNA-1273 is effective in preventing SARS-CoV-2 infection in preschool children (6 months-6 years old). Both BNT162b2 and mRNA-1273 are effective in preventing SARS-CoV-2 infection in school-aged children and adolescents, thereby preventing post-coronavirus disease (COVID) conditions. The common side effects of vaccination are pain at the injection site, fatigue, and headache. Myocarditis and pericarditis are uncommon. Monitoring post-vaccination troponin levels may help prevent severe cardiac events. The SARS-CoV-2 coronavirus mutates its genome to overcome the herd immunity provided by mass vaccinations; therefore, we may need to develop new generations of vaccines, such as those using viral nucleocapsid proteins as antigens. In conclusion, the mRNA vaccines are generally safe and effective in preventing severe diseases and hospitalization among children and adolescents.

Pneumopericardium after peritoneopericardial diaphragmatic hernia repair in a dog

A one-year-old neutered Goldendoodle presented for evaluation. One week prior to presentation, surgical closure of a peritoneopericardial diaphragmatic hernia (PPDH) was performed via ventral midline celiotomy. Since the procedure, the dog had been lethargic and anorexic at home. Thoracic radiographs revealed a pneumopericardium. Pericardiocentesis was performed which evacuated approximately 100 mL of air from the pericardial sac. The dog recovered well and began eating in the hospital and resumed normal activity. This is the first reported case of a pneumopericardium post-PPDH repair requiring pericardiocentesis. Clinicians should be aware of this rare complication in postoperative PPDH patients.

The study of cancer cell in stromal environment through induced pluripotent stem cell-derived mesenchymal stem cells

BACKGROUND

The development of mesenchymal stem cells (MSCs) has gained reputation from its therapeutic potential in stem cell regeneration, anti-inflammation, tumor suppression, and drug delivery treatment. Previous studies have shown MSCs have both promoting and suppressing effects against cancer cells. While the limitation of obtaining a large quantity of homologous MSCs for studies and treatment remains a challenge, an alternative approach involving the production of MSCs derived from induced pluripotent stem cells (iPSCs; induced MSCs [iMSCs]) may be a promising prospect given its ability to undergo prolonged passage and with similar therapeutic profiles as that of their MSC counterparts. However, the influence of iMSC in the interaction of cancer cells remains to be explored as such studies are not well established. In this study, we aim to differentiate iPSCs into MSC-like cells as a potential substitute for adult MSCs and evaluate its effect on non-small-cell lung cancer (NSCLC).

METHODS

iMSCs were derived from iPSCs and validated with reference to the International Society of Cellular Therapy guidelines on MSC criteria. To create a stromal environment, the conditioned medium (CM) of iMSCs was harvested and applied for coculturing of NSCLC of H1975 at different concentrations. The H1975 was then harvested for RNA extraction and subjected to next-generation sequencing (NGS) for analysis.

RESULTS

The morphology of iMSCs-CM-treated H1975 was different from an untreated H1975. Our NGS data suggest the occurrence of apoptotic events and the presence of cytokines from H1975's RNA that are treated with iMSCs-CM.

CONCLUSION

Our results have shown that iMSCs may suppress the growth of H1975 by releasing proapoptotic cytokines into coculture media. Using iPSC-derived MSC models allows a deeper study of tumor cross talk between MSC and cancer cells that can be applied for potential future cancer therapy.

[Multidisciplinary regenerative treatment and mechanisms for rescuing a severe calciphylaxis patient with human amnion-derived mesenchymal stem cells]

Calciphylaxis is a rare disease with severe pain and high-mortality due to cutaneous ischemic necrosis and infection that currently lacks proved effective therapies. The occurrence of calciphylaxis in end stage kidney disease (ESKD) patients is known as calcific uremic arteriolopathy (CUA), which is characterized histologically by dermal microvessel calcification, intimal fibroplasia and microthrombosis. Here we innovatively treated a severe CUA patient with human amnion-derived mesenchymal stem cells (hAMSCs). A 34-year-old uremic woman was presented with progressive, painful malodorous ulcers in buttocks and mummified lower limbs. Skin pathological features supported the diagnosis of calciphylaxis. The patient was refractory to conventional multidisciplinary symptomatic therapies. With the approval of our hospital ethics committee, she was treated with hAMSCs including intravenous and local intramuscular injection, and external application of hAMSC culture supernatant to the wound area. During 15-month follow-up, the patient had regeneration of skin and soft tissues, with improved blood biochemical, inflammatory, mineral and bone metabolic indices and immunoregulation effects. After 15-month hAMSC treatment, the score of pain visual analog scale (VAS) decreased from 10 to 0, Bates-Jensen wound assessment tool (BWAT) score decreased from 65 to 13, and wound-quality of life (Wound-QoL) questionnaire score decreased from 68 to 0. We propose that hAMSC treatment is promising for CUA patients. The therapy is potentially involved in the multiple beneficial effects of inhibiting vascular calcification, stimulating angiogenesis and myogenesis, modulating adverse inflammatory and immunologic responses, promoting re-epithelialization and restoring skin integrity.

State-of-the-Art Molecular Oncology of Lung Cancer in Taiwan

Lung cancers are life-threatening malignancies that cause great healthcare burdens in Taiwan and worldwide. The 5-year survival rate for Taiwanese patients with lung cancer is approximately 29%, an unsatisfactorily low number that remains to be improved. We first reviewed the molecular epidemiology derived from a deep proteogenomic resource in Taiwan. The nuclear factor erythroid 2-related factor 2 (NRF2)antioxidant mechanism was discovered to mediate the oncogenesis and tumor progression of lung adenocarcinoma. Additionally, DNA replication, glycolysis and stress response are positively associated with tumor stages, while cell-to-cell communication, signaling, integrin, G protein coupled receptors, ion channels and adaptive immunity are negatively associated with tumor stages. Three patient subgroups were discovered based on the clustering analysis of protein abundance in tumors. The first subgroup is associated with more advanced cancer stages and visceral pleural invasion, as well as higher mutation burdens. The second subgroup is associated with EGFR L858R mutations. The third subgroup is associated with PI3K/AKT pathways and cell cycles. Both EGFR and PI3K/AKT signaling pathways have been shown to induce NRF2 activation and tumor cell proliferation. We also reviewed the clinical evidence of patient outcomes in Taiwan given various approved targeted therapies, such as EGFR-tyrosine kinase inhibitors and anaplastic lymphoma kinase (ALK)inhibitors, in accordance with the patients’ characteristics. Somatic mutations occurred in EGFR, KRAS, HER2 and BRAF genes, and these mutations have been detected in 55.7%, 5.2%, 2.0% and 0.7% patients, respectively. The EGFR mutation is the most prevalent targetable mutation in Taiwan. EML4-ALK translocations have been found in 9.8% of patients with wild-type EGFR. The molecular profiling of advanced NSCLC is critical to optimal therapeutic decision-making. The patient characteristics, such as mutation profiles, protein expression profiles, drug-resistance profiles, molecular oncogenic mechanisms and patient subgroup systems together offer new strategies for personalized treatments and patient care.

Stability profiling and degradation products of dihydromyricetin in Dulbecco's modified eagle's medium

Dihydromyricetin has shown many bioactivities in cell level. However, dihydromyricetin was found to be highly instable in cell culture medium DMEM. Here, the underlying degradation mechanism was investigated via UPLC-MS/MS analysis. Dihydromyricetin was mainly converted into its dimers and oxidized products. At lower temperature, dihydromyricetin in DMEM showed higher stability. Vitamin C increased the stability of dihydromyricetin in DMEM probably due to its high antioxidant potential.

[A study of the effectiveness of nucleos(t)ide analogues in the treatment of HBeAg- positive chronic hepatitis B with normal alanine aminotransferase and high level of HBV DNA]

Objective: To investigate the effectiveness of nucleos(t)ide analogues in the treatment of HBeAg-positive chronic hepatitis B with normal alanine aminotransferase and high level of HBV DNA. Methods: Treatment-naïve chronic hepatitis B patients who were followed up at the Center of Infectious Diseases, West China Hospital of Sichuan University from January 2019 to January 2020 were selected as subjects. Demographic characteristics, the results of laboratory examination before treatment and one year after treatment were retrospectively collected. Patients were divided into tenofovir dipivoxil (TDF) and propofol fumurate tenofovir (TAF) treatment group according to different types of medication. The changes of serum HBV DNA level, HBeAg serological conversion and HBsAg quantitative level were analyzed and compared between the two groups. Results: A total of 38 cases were enrolled. Among them, there were 16 and 22 cases in the TDF and TAF group, respectively. There was no statistically significant difference in demographic characteristics, baseline HBV DNA levels and HBsAg quantitative levels between the two groups. Virological response was achieved in 60.5% (23/38) of patients after one year of antiviral therapy. Serum HBV DNA levels below the lower limit of detection [68.2% (15/22) vs. 50.0% (8/16), P=0.258] and higher HBeAg seroconversion rate [18.2%] (4/22) vs. 6.3% (1/16), P=0.374] was obtained in TAF than TDF group; however, there was no statistically significant differences between the two. Serum HBsAg quantitative level was significantly reduced with TDF and TAF treatment. In addition, alanine aminotransferase elevation was reduced in TAF than TDF treated group. Multivariate logistic regression analysis showed that patient age was an independent predictor of a virological response to antiviral therapy. Conclusion: HBeAg-positive CHB patients with normal alanine aminotransferase, and high HBV DNA level can obtain better curative effect after TDF and TAF treatment.

[The feasibility analysis of multi-slice spiral CT features of gastric stromal tumors in predicting pathological National Institutes of Health risk classification]

Objective: To investigate the feasibility of multi-slice spiral CT(MSCT) imaging features of gastric stromal tumor (GST) in predicting pathological NIH risk classification, providing imaging basis for patients with GST before treatment. Methods: The clinical and CT imaging data of 504 patients(506 GST lesions), 259males and 245 females, aged from 13 to 85(60±11) years, with GST confirmed by surgery and pathology collected in the Zhongshan Hospital Affiliated to Fudan University and the Affiliated TCM Hospital of Southwest Medical University. According to pathological NIH risk classification, 506 lesions were divided into low risk group (very low and low risk degree, 277 lesions) and high risk group (medium and high risk degree, 229 lesions).Clinical data and imaging characteristics were compared between two groups. Multivariate logistic regression analysis was performed to screen out independent risk factors for statistically significant imaging indicators. Receiver operating curve (ROC) was used to evaluate the predictive value of tumor length for risk classification. Resulst: Between low risk group and high risk group,there were significant differences in gender(male/female:131/146 vs 129/100), gastrointestinal bleeding(present/absent:39/238 vs 59/170), morphology(regular/Irregular:218/59 vs 95/134), calcification(present/absent:36/241 vs 53/176), degree of necrosis(0°/Ⅰ°/Ⅱ°/Ⅲ°:197/61/16/3 vs 58/98/32/41), ulceration(present/absent:32/245 vs 94/135), growth pattern(endophytic/exophytic/mixed:102/105/70 vs 44/98/87), tumor location(fundus/cardia/body/angle/antrum:98/7/135/12/25 vs 98/6/114/5/6), feeding artery(present/absent:32/245 vs 104/125), vascular enhancement(present/absent:19/258 vs 88/141), effusion of around the disease(present/absent:0/277 vs 13/216), positive sign of fat around the disease(present/absent:0/277 vs 30/199),maximum long diameter[2.82(2.04,3.80) cm vs 5.93(4.06,8.29) cm] and short diameter [2.31(1.60,2.88) cm vs 4.40(3.21,6.37) cm]of tumor(all P<0.05).The maximum long diameter of tumor (OR=2.08,95%CI:1.35-3.20) and ulceration positive(OR=2.01,95%CI:1.03-3.92) were independent risk factors of risk classification(all P<0.05).Gastric antrum was used as the reference for tumor location, gastric fundus(OR=7.77,95%CI:2.00-30.24) and gastric body(OR=3.93,95%CI:1.03-15.01) were independent risk factors of risk classification(all P<0.05).The area under curve(AUC) of the maximum long diameter of tumor for predicting risk classification was 0.87, and the optimal critical value, sensitivity and specificity were 4.98cm, 62.9% and 95.3% respectively. Conclusions: MSCT image features of GST had certain characteristics. MSCT has certain predictive value for pathological NIH risk classification of GST, which can provide certain imaging basis for patients before treatment.

[Analysis of failure causes and countermeasures of automatic coagulation analyzer detection of thrombin time]

To study the failure alarm information displayed on the automatic coagulation analyzer (coagulation method) of thrombin time (TT), and formulate the coping strategies combined with clinical information. Methods: A total of 233 failed TT blood samples [132 males, 101 females, with a median age of 73 (66, 79) years] were selected from 21 359 inpatients in Peking University First Hospital from January to June 2021. The statistical analysis was made and the failure causes and solutions were summarized according to the coagulation curve and the error codes displayed on the coagulation instrument, in combination with the clinical information, sample characteristics, medication status and other reasons. Meanwhile, a total of 96 TT detection failed lipid blood samples [56 males, 40 females, with a median age of 72 (65, 79) years] were analyzed from the inpatients in Peking University First Hospital from July to November 2021. TT results were obtained by artificial coagulation curve interpretation method, magnetic bead method and high-speed centrifugal re-detection method, respectively. The TT results of the three methods were compared. Results: The proportion of 233 failed TT tests from the total number of samples was 1.1% (233/21 359). There were 41.2% (96/233) samples with lipids, 23.2% (54/233) samples with heparin interference, 22.3% (52/233) samples with oral anticoagulant, and 13.3% (31/233) samples with micro-coagulation or insufficient plasma volume among these test failure samples. The classifications for these alarm information of coagulation curves showed on the instrument were as follows: 32.6% (76/233) of samples with higher changes in absorbance at baseline (SD>2 mAbs), 30.5% (71/233) of samples without peak values of second derivative, 25.8% (60/233) of samples with absorbance difference<35 mAbs between baseline and plateau period, 8.6% (20/233) samples with too low starting point or no starting point, and 2.6% (6/233) samples without coagulation curves. Among these 233 samples, there were 55.8% (130/233) samples that could be manually judged according to the reaction principle and standard coagulation curve pattern. Among the 96 samples that failed in coagulation method due to lipemia, there were 78 samples with sufficient blood volume tested by magnetic bead method. The TT results of the high-speed centrifugal redetection method, artificial coagulation curve interpretation method and magnetic bead method were 14.10 (14.80, 13.38) s, 14.30 (14.99, 13.60) s, and 15.65 (17.25, 14.65) s, respectively, but the difference was not statistically significant (P=0.055). For 78 lipid samples, there was a correlation between the results of the artificial coagulation curve interpretation method and the results of magnetic bead method (r=0.99,P=0.001). Conclusions: For those samples failed in TT detection by coagulation method on automatic coagulation instrument, the cause of failure can be analyzed through coagulation curve and alarm information. For the lipid samples, TT results can be obtained by manual interpretation method, high-speed centrifugation method and magnetic bead method.

[The disease burden of degenerative mitral valve disease in the Chinese population from 1990 to 2019]

Objective: To explore the trend of disease burden of degenerative mitral valve disease (DMVD) in the Chinese population from 1990 to 2019. Methods: Based on the 2019 Global Burden of Disease database (GBD 2019), the number of patients, the number of new cases, the number of deaths, the disability-adjusted life years (DALY) as well as the prevalence, incidence and death rate, DALY rate and their age-standardized rates were used to analyze the trend of the burden of DMVD in the Chinese population from 1990 to 2019. Results: In 2019, the number of patients, the number of new cases, and the number of deaths with DMVD in China were 461.2, 27.0 and 0.129 ten thousand, respectively, which increased by 209.0%, 199.1% and 13.2% when compared with 1990. In 2019, the age-standardized prevalence, incidence and death rate were 228.1/100 000, 12.7/100 000 and 0.075/100 000, respectively. Compared with 1990, the change of the age-standardized prevalence, incidence and death rate were 32.6%, 42.8% and -54.1%, respectively. In addition, the 2019 data also showed that the age-standardized prevalence and incidence were higher in females than in males (the age-standardized prevalence was 190.1 (181.5-198.9)/100 000 for males and 262.0 (250.3-273.9)/100 000 for females); the age-standardized incidence was 10.5 (10.0-11.0)/100 000 for males and 14.9 (14.3-15.6)/100 000 for females. The age group with the largest number of DMVD patients was 65 to 69 years old, and the highest incidence was 60 to 64 years old. From 1990 to 2019, DALY caused by DMVD showed an upward trend in China, from 46 439 person-years in 1990 to 69 402 person-years in 2019, with an increase of 49.4%. While the age-standardized DALY rate continued to decline, from 5.5/100 000 in 1990 to 3.8/100 000 in 2019, with a drop of 30.8%. The DALY and the age-standardized DALY rate of females were always higher than that of males in different years. Conclusion: From 1990 to 2019, DALY and the age-standardized prevalence and incidence of DMVD in China shows an increasing trend, and the disease burden caused by DMVD is severe in China.

Circular RNAs Modulate Cancer Hallmark and Molecular Pathways to Support Cancer Progression and Metastasis

Simple Summary

Circular RNAs (circRNA) are a type of RNA molecule of circular shape that are now being extensively studied due to the important roles they play in different biological processes. In addition, they were also shown to be implicated in disease such as cancer. Cancer is a complex process which is often defined by a combination of specific processes called cancer hallmarks. In this review, we summarize the literature on circRNAs in cancer and classify them as being implicated in specific cancer hallmarks.

Abstract

Circular RNAs (circRNAs) are noncoding products of backsplicing of pre-mRNAs which have been established to possess potent biological functions. Dysregulated circRNA expression has been linked to diseases including different types of cancer. Cancer progression is known to result from the dysregulation of several molecular mechanisms responsible for the maintenance of cellular and tissue homeostasis. The dysregulation of these processes is defined as cancer hallmarks, and the molecular pathways implicated in them are regarded as the targets of therapeutic interference. In this review, we summarize the literature on the investigation of circRNAs implicated in cancer hallmark molecular signaling. First, we present general information on the properties of circRNAs, such as their biogenesis and degradation mechanisms, as well as their basic molecular functions. Subsequently, we summarize the roles of circRNAs in the framework of each cancer hallmark and finally discuss the potential as therapeutic targets.

[Performance evaluation and validation of automated digital image analysis in peripheral blood cells morphology examination]

Objective: To verify and evaluate the performance of automated digital image(DIA) for peripheral blood cell morphology examination. Methods: Three hundred and seventy-nine routine peripheral blood smears and 18 plasmodium positive peripheral blood smears were collected. Blood smears were made and stained by Wright -Giemsa method.White blood cell (WBC) differentiation of blood smears were pre-classified by DIA (DIA direct classification), re-classified (manually reviewed after DIA classification), and artificially classified under microscope. the inter-assay and intra-assay coefficients of variation (CV) of DIA were respectively calculated for repeatability verification. Taking the artificial microscopy as the gold standard, the sensitivity、specificity and accuracy of DIA were calculated. The DIA ability of peripheral blood blast cell morphological count, platelet (PLT) morphological count and morphological examination of plasmodium were also verified. Results: Except for eosinophils and basophils, the inter-assay and intra-assay CV of WBC classification by DIA in normal samples were < 10%. The CV of WBC classification in abnormal samples increased with the decrease of cell percentage. The sensitivity, specificity and accuracy of DIA pre-classification were 90.5%, 99.2%, 98.2%. Through pre-classification and re-classification by DIA,the results of the blood smears which triggered blast cell alarm had a good correlation with manual classification(r=0.812, 0.983, both P<0.01). The PLT morphological count by DIA had high correlation with hematology analyzer (r=0.946, P<0.01). The deviation absolute value of two methods of PLT count was < 15%, while in PLT aggregation or giant thrombocytosis samples,the deviation absolute value of PLT count by two methods was > 15%. After image acquisition by DIA, 17 plasmodium trophozoites were detected in 18 plasmodium-positive peripheral blood smears, and the images were clear. Conclusions: The DIA system has good repeatability, high sensitivity, specificity and accuracy in peripheral blood WBC classification. Its pre-classification and re-classification results have high correlation with the manual classification results.

Strategic Decoy Peptides Interfere with MSI1/AGO2 Interaction to Elicit Tumor Suppression Effects

Simple Summary

Peptide drugs that can specifically target undesirable protein–protein interactions that lead to oncogenic developments have emerged as the next era of future medicine for cancers. To combat GBM tumor progression, our study offers an alternative therapeutic strategy via targeting the protein–protein interaction between MSI1 and AGO2 with synthetic peptides identified from the C-terminus of MSI1 in peptide arrays. Our present data revealed for the first time that peptidic disruption to the MSI1/AGO2 complex known for promoting cancer stemness and progression could lead to encouraging therapeutic efficacy at both in vitro and in vivo levels. The significantly suppressed tumor growth and prolonged survival rates in PDX tumor models by decoy peptides evidently provided a new rationale for stratifying patients with MSI1/AGO2-targeted therapeutics.

Abstract

Peptide drugs that target protein–protein interactions have attracted mounting research efforts towards clinical developments over the past decades. Increasing reports have indicated that expression of Musashi 1 (MSI1) is tightly correlated to high grade of cancers as well as enrichment of cancer stem cells. Treatment failure in malignant tumors glioblastoma multiform (GBM) had also been correlated to CSC-regulating properties of MSI1. It is thus imperative to develop new therapeutics that could effectively improve current regimens used in clinics. MSI1 and AGO2 are two emerging oncogenic molecules that both contribute to GBM tumorigenesis through mRNA regulation of targets involved in apoptosis and cell cycle. In this study, we designed peptide arrays covering the C-terminus of MSI1 and identified two peptides (Pep#11 and Pep#26) that could specifically interfere with the binding with AGO2. Our Biacore analyses ascertained binding between the identified peptides and AGO2. Recombinant reporter system Gaussian luciferase and fluorescent bioconjugate techniques were employed to determine biological functions and pharmacokinetic characteristics of these two peptides. Our data suggested that Pep#11 and Pep#26 could function as decoy peptides by mimicking the interaction function of MSI1 with its binding partner AGO2 in vitro and in vivo. Further experiments using GMB animal models corroborated the ability of Pep#11 and Pep#26 in disrupting MSI1/AGO2 interaction and consequently anti-tumorigenicity and prolonged survival rates. These striking therapeutic efficacies orchestrated by the synthetic peptides were attributed to the decoy function to C-terminal MSI1, especially in malignant brain tumors and glioblastoma.

[Value of radiomics model based on dynamic contrast-enhanced magnetic resonance imaging in differentiation fat-poor angiomyolipoma from alpha-fetoprotein-negative hepatocellular carcinoma in the background of non-cirrhotic liver]

Objective: To explore the value of radiomics model based on dynamic contrast-enhanced magnetic resonance imaging (MRI) in differentiation fat-poor angiomyolipoma (fp-AML) from alpha-fetoprotein-negative hepatocellular carcinoma (n-HCC) in the background of non-cirrhotic liver. Methods: The complete data of 121 patients from Guangdong Provincial People's Hospital, Zhongshan Hospital Affiliated to Fudan University and Sun Yat-sen University Cancer Center with hepatic fp-AML and n-HCC confirmed by pathology from October 2010 to July 2020 were retrospectively analyzed. Among them, 75 were males and 46 were females, aged from 23 to 80 (55±12) years. A total of 93 patients from Zhongshan Hospital Affiliated to Fudan University were divided into the training cohort (n=75) and internal test cohort (n=18) according to entry time, and the patients of other 2 hospitals were divided into external test cohort (n=28). The radiomics features were extracted from the preoperative triple-phase contrast-enhanced images. The feature selection algorithm based on Joint Mutual Information Maximisation (JMIM) was used to extract the optimal feature subset, and support vector machine (SVM) was used to build the radiomics model. The diagnostic performance of radiomics model was evaluated using the receiver operating characteristic (ROC) curve, and was compared with that of two radiologists. Results: In the internal cohort, the area under the curve (AUC) for the differential diagnosis between fp-AML and n-HCC of the radiomics model was 0.819 (with an accuracy of 72.2%), outperforming than radiologist 1 with 10 years of diagnostic experience (AUC=0.542, P=0.029) and radiologist 2 with 2 years of diagnostic experience (AUC=0.375, P=0.004). In the external cohort, the AUC of the radiomics model was 0.772 (with and accuracy of 71.4%), which was comparable to that of radiologist 1 (AUC=0.661, P=0.442) and better than that of radiologist 2 (AUC=0.400, P=0.008). Conclusion: The radiomics model based on dynamic contrast-enhanced MRI is of high accuracy for preoperatively differentiating hepatic fp-AML from n-HCC in the noncirrhotic liver.

Circular RNA hsa_circ_0000190 Facilitates the Tumorigenesis and Immune Evasion by Upregulating the Expression of Soluble PD-L1 in Non-Small-Cell Lung Cancer

Lung cancer is the leading cause of death from cancer in Taiwan and throughout the world. Immunotherapy has revealed promising and significant efficacy in NSCLC, through immune checkpoint inhibition by blocking programmed cell death protein (PD)-1/PD-1 ligand (PD-L1) signaling pathway to restore patients’ T-cell immunity. One novel type of long, non-coding RNAs, circular RNAs (circRNAs), are endogenous, stable, and widely expressed in tissues, saliva, blood, urine, and exosomes. Our previous results revealed that the plasma level of hsa_circ_0000190 can be monitored by liquid-biopsy-based droplet digital PCR and may serve as a valuable blood-based biomarker to monitor the disease progression and the efficacy of immunotherapy. In this study, hsa_circ_0000190 was shown to increase the PD-L1 mRNA-mediated soluble PD-L1 (sPD-L1) expression, consequently interfering with the efficacy of anti-PD-L1 antibody and T-cell activation, which may result in immunotherapy resistance and poor outcome. Our results unraveled that hsa_circ_0000190 facilitated the tumorigenesis and immune evasion of NSCLC by upregulating sPD-L1 expression, potentially developing a different aspect in elucidating the molecular immunopathogenesis of NSCLC. Hsa_circ_0000190 upregulation can be an effective indicator for the progression of NSCLC, and hsa_circ_0000190 downregulation may possess a potential therapeutic value for the treatment of NSCLC in combination with immunotherapy.

Oncogenic circRNA hsa_circ_0000190 modulates EGFR/ERK pathway in promoting NSCLC

Lung cancers (LC) are the leading cause of cancer-related mortality worldwide, and the majority of LC are non-small cell lung carcinoma (NSCLC). Overexpressed or activated EGFR has been associated with a poor prognosis in NSCLC. We previously identified a circular non-coding RNA, hsa_circ_0000190 (C190), as a negative prognostic biomarker of LC. Here we attempted to dissect the mechanistic function of C190 and test the potential of C190 as a therapeutic target in NSCLC. C190 was upregulated in both NSCLC clinical samples and cell lines. Activation of the EGFR pathway increased C190 expression through a MAPK/ERK-dependent mechanism. Transient and stable overexpression of C190 induced ERK1/2 phosphorylation, proliferation, and migration in vitro and xenograft tumor growth in vivo. RNA sequencing and Expression2Kinases (X2K) analysis indicated that kinases associated with cell cycle and global translation are involved in C190-activated networks, including CDKs and p70S6K, which were further validated by immunoblotting. CRISPR/Cas13a-mediated knockdown of C190 decreased proliferation and migration of NSCLC cells in vitro and suppressed tumor growth in vivo. TargetScan and CircInteractome databases predicted that C190 targets CDKs by sponging miR-142-5p. Analysis of clinical LC samples showed that C190, CDK1, and CDK6 expression were significantly higher in advanced-stage LC than in early-stage LC. In summary, C190 is directly involved in EGFR-MAPK-ERK signaling and may serve as a potential therapeutic target for the treatment of NSCLC.

[Nodular regenerative hyperplasia of liver caused by chemotherapy: magnetic resonance imaging features]

Objective: To investigate the MRI features of hepatic nodular regenerative hyperplasia (NRH) induced by chemotherapy. Methods: The clinical data and MRI of 20 cases with hepatic NRH induced by chemotherapy and confirmed by pathology in Zhongshan Hospital Fudan University from August 2014 to May 2019 were retrospectively analyzed. There were 13 males and 7 females, with an average age of 49.8 ± 9.7 years. Contrast-enhanced MR scan with Gd-DTPA was performed eighteen patients, and two patients underwent contrast-enhanced MR scan with hepatobiliary specific contrast (Gd-EOB-DTPA). The image analysis includes the number, location, size, shape, signal intensity in plain scan and enhancement pattern of lesions. The apparent diffusion coefficient (ADC) values of the lesions and adjacent hepatic parenchyma were measured on the ADC map, and the difference was compared with paired sample t test. Results: A total of 36 lesions in 20 patients were rounded or oval, including 23 (63.9%) lesions in the right lobe, 12 (33.3%) in the left lobe and 1 (2.8%) in the caudate lobe. The average diameter of all lesions was 15.4 ± 6.4 (7.0-37.0) mm. The boundary was clear in 9 (25.0%) lesions and blurred in 27 (75%) lesions. In T1WI, 35 (97.2%) lesions showed slightly hypointensity, and in 1 (2.8%) lesion was iosintensity. All 36 lesions showed slightly hyperintensity in T2WI. 33 (91.7%) lesions showed slightly hyperintensity in DWI, and 3 (8.3%) lesions showed iosintensity. 31 lesions with Gd-DTPA enhanced MR scan were significantly enhanced in the arterial phase and showed slightly high signal intensity in early portal vein phase, late portal vein phase and equilibrium phase. 5 lesions with Gd-EOB-DTPA enhanced MR scan were also significantly enhanced in the arterial phase and showed slightly high signal intensity in early portal vein phase, late portal vein phase and equilibrium phase, then all lesions showed circular high signal intensity in hepatobiliary specific phase. The average ADC value of 29 lesions was (1.471 ± 0.253) × 10(-3) mm(2)/s, and that of adjacent liver parenchyma was (1.460 ± 0.235) ×10(-3) mm(2)/s. There was no significant difference between the two groups (P > 0.05). Conclusion: MR findings of NRH induced by chemotherapy have certain characteristics, and the morphological manifestations, diffusion-weighted imaging, enhanced imaging and hepatobiliary specific phase features of the lesions can help to diagnose the disease.

Dual DNA Transfection Using 1,6-Hexanedithiol-Conjugated Maleimide-Functionalized PU-PEI600 For Gene Correction in a Patient iPSC-Derived Fabry Cardiomyopathy Model

Non-viral gene delivery holds promises for treating inherited diseases. However, the limited cloning capacity of plasmids may hinder the co-delivery of distinct genes to the transfected cells. Previously, the conjugation of maleimide-functionalized polyurethane grafted with small molecular weight polyethylenimine (PU-PEI₆₀₀-Mal) using 1,6-hexanedithiol (HDT) could promote the co-delivery and extensive co-expression of two different plasmids in target cells. Herein, we designed HDT-conjugated PU-PEI₆₀₀-Mal for the simultaneous delivery of CRISPR/Cas9 components to achieve efficient gene correction in the induced pluripotent stem cell (iPSC)-derived model of Fabry cardiomyopathy (FC) harboring GLA IVS4 + 919 G > A mutation. This FC in vitro model recapitulated several clinical FC features, including cardiomyocyte hypertrophy and lysosomal globotriaosylceramide (Gb3) deposition. As evidenced by the expression of two reporter genes, GFP and mCherry, the addition of HDT conjugated two distinct PU-PEI₆₀₀-Mal/DNA complexes and promoted the co-delivery of sgRNA/Cas9 and homology-directed repair DNA template into target cells to achieve an effective gene correction of IVS4 + 919 G > A mutation. PU-PEI₆₀₀-Mal/DNA with or without HDT-mediated conjugation consistently showed neither the cytotoxicity nor an adverse effect on cardiac induction of transfected FC-iPSCs. After the gene correction and cardiac induction, disease features, including cardiomyocyte hypertrophy, the mis-regulated gene expressions, and Gb3 deposition, were remarkably rescued in the FC-iPSC-differentiated cardiomyocytes. Collectively, HDT-conjugated PU-PEI₆₀₀-Mal-mediated dual DNA transfection system can be an ideal approach to improve the concurrent transfection of non-viral-based gene editing system in inherited diseases with specific mutations.

Mitochondrial transport mediates survival of retinal ganglion cells in affected LHON patients

The mutations in the genes encoding the subunits of complex I of the mitochondrial electron transport chain are the most common cause of Leber's hereditary optic neuropathy (LHON), a maternal hereditary disease characterized by retinal ganglion cell (RGC) degeneration. The characteristics of incomplete penetrance indicate that nuclear genetic and environmental factors also determine phenotypic expression of LHON. Therefore, further understanding of the role of mutant mitochondrial nicotinamide adenine dinucleotide dehydrogenase subunit proteins and nuclear genetic factors/environmental effects in the etiology of LHON is needed. In this study, we generated human-induced pluripotent stem cells (hiPSCs) from healthy control, unaffected LHON mutation carrier, and affected LHON patient. hiPSC-derived RGCs were used to study the differences between affected and unaffected carriers of mitochondrial DNA point mutation m.11778G > A in the MT-ND4 gene. We found that both mutated cell lines were characterized by increase in reactive oxygen species production, however, only affected cell line had increased levels of apoptotic cells. We found a significant increase in retrograde mitochondria and a decrease in stationary mitochondria in the affected RGC axons. In addition, the messenger RNA and protein levels of KIF5A in the LHON-affected RGCs were significantly reduced. Antioxidant N-acetyl-L-cysteine could restore the expression of KIF5A and the normal pattern of mitochondrial movement in the affected RGCs. To conclude, we found essential differences in the mutually dependent processes of oxidative stress, mitochondrial transport and apoptosis between two LHON-specific mutation carrier RGC cell lines, asymptomatic carrier and disease-affected, and identified KIF5A as a central modulator of these differences.

Deep proteogenomic investigations elucidate the NRF2 antioxidant mechanism as a major driving mechanism of lung adenocarcinoma in Asia

BACKGROUND

Lung adenocarcinoma is a global leading cause of death. Despite modern therapeutic interventions, undesirable outcomes such as drug resistances and disease recurrence still occur. Therefore, continued investigations of disease driving mechanisms and counteracting strategies are urgently needed.

METHODS

We re-visited two deep-proteogenomic resources of lung adenocarcinoma published recently. These resources were derived from patient cohorts with decent sizes in Taiwan and China. The gene set enrichment analysis (GSEA) was performed. A heatmap was produced by the generalized association plot (GAP).

RESULTS

Among 189 common oncogenic pathways investigated, the nuclear factor erythroid 2-related factor 2 (NRF2) downstream antioxidant mechanism was uncovered for the first time the leading oncogenic mechanism of lung adenocarcinoma in Taiwan. The gene levels of NRF2 (also known as NFE2L2) is negatively correlated with those of KEAP1 (Pearson's correlation = -0.275, p = 0.009) in patients' tumor tissues. Furthermore, the protein levels of EIF2S2 and PGD are higher in patients with more advanced stages in the Taiwan cohort (p = 0.001 and 0.05, respectively), and are indicative of poorer progression-free survival (PFS) and overall survival (OS) in the China cohort (all Cox-regression p < 0.05). On the other hand, EPHX1 is higher in patients with earlier stages in Taiwan (p = 0.003), and are indicative of better PFS and OS in China (both Cox-regression p < 0.05). When the patients were stratified using the median protein abundances for Kaplan-Meier visualizations, patient strata with higher EIF2S2, PGD, and EPHX1 have significantly poorer PFS (log-rank p = 0.041); poorer OS (p = 0.006), and better PFS and OS (p = 0.001 and 0.030), respectively.

CONCLUSION

The NRF2 downstream antioxidant mechanism is one major driving mechanism of lung adenocarcinoma in Asia, and represents important directions for future therapeutic interventions. Major downstream proteins such as EIF2S2, PGD, and EPHX1 are indicative of cancer stages and prognosis.

Cytokine and epigenetic regulation of programmed death-ligand 1 in stem cell differentiation and cancer cell plasticity

Programmed death-ligand 1 (PD-L1), an immune checkpoint ligand, is recognized as a potential target for cancer immunotherapy as well as for the induction of transplantation tolerance. However, how the crosstalk between stem cell programming and cytokine signaling regulates PD-L1 expression during stem cell differentiation and cancer cell plasticity remains unclear. Herein, we reported that PD-L1 expression was regulated by SOX2 during embryonic stem cell (ESC) differentiation and lung cancer cell plasticity. PD-L1 was induced during ESC differentiation to fibroblasts and was downregulated during SOX2-mediated reprogramming of fibroblasts to induced pluripotent stem cells (iPSCs). Furthermore, SOX2 activation affected cancer cell plasticity and inhibited PD-L1 expression in lung cancer cells. We discovered that the H3K27ac signal at the PD-L1 locus was enhanced during ESC differentiation to fibroblasts as well as during cancer plasticity of SOX2-positive lung cancer cells to SOX2-negative counterparts. Romidepsin, an epigenetic modifier, induced PD-L1 expression in lung cancer cells, whereas TGF-β stimulation downregulated SOX2 but upregulated PD-L1 expression in lung cancer cells. Furthermore, in addition to PD-L1, the expressions of EGFR and its ligand HBEGF were downregulated by activation of endogenous SOX2 expression during lung cancer cell plasticity and iPSC reprogramming, and the activation of EGFR signaling by HBEGF upregulated PD-L1 expression in lung cancer cells. Together, our results reveal the crosstalk between SOX2 programming and cytokine stimulation influences PD-L1 expression, and these findings may provide insights into PD-L1-mediated therapeutics.

Single-cell RNA sequencing in human lung cancer: Applications, challenges, and pathway towards personalized therapy

Lung cancer is one of the most prevalent human cancers, and single-cell RNA sequencing (scRNA-seq) has been widely used to study human lung cancer at the cellular, genetic, and molecular level. Even though there are published reviews, which summarized the applications of scRNA-seq in human cancers like breast cancer, there is lack of a comprehensive review, which could effectively highlight the broad use of scRNA-seq in studying lung cancer. This review, therefore, was aimed to summarize the various applications of scRNA-seq in human lung cancer research based on the findings from different published in vitro, in vivo, and clinical studies. The review would first briefly outline the concept and principle of scRNA-seq, followed by the discussion on the applications of scRNA-seq in studying human lung cancer. Finally, the challenges faced when using scRNA-seq to study human lung cancer would be discussed, and the potential applications and challenges of scRNA-seq to facilitate the development of personalized cancer therapy in the future would be explored.

Pandemic analysis of infection and death correlated with genomic open reading frame 10 mutation in severe acute respiratory syndrome coronavirus 2 victims

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues the pandemic spread of the coronavirus disease 2019 (COVID-19), over 60 million people confirmed infected and at least 1.8 million dead. One of the most known features of this RNA virus is its easiness to be mutated. In late 2020, almost no region of this SARS-CoV-2 genome can be found completely conserved within the original Wuhan coronavirus. Any information of the SARS-CoV-2 variants emerged through as time being will be evaluated for diagnosis, treatment, and prevention of COVID-19.

METHODS

We extracted more than two million data of SARS-CoV-2 infected patients from the open COVID-19 dashboard. The sequences of the 38-amino acid putative open reading frame 10 (Orf10) protein within infected patients were gathered output through from National Center for Biotechnology Information and the mutation rates in each position were analyzed and presented in each month of 2020. The mutation rates of A8 and V30 within Orf10 are displayed in selected counties: United States, India, German, and Japan.

RESULTS

The numbers of COVID-19 patients are correlated to the death numbers, but not with the death rates (stable and <3%). The amino acid positions locating at A8(F/G/L), I13, and V30(L) within the Orf10 sequence stay the highest mutation rate; N5, N25, and N36 rank at the lowest one. A8F expressed highly dominant in Japan (over 80%) and German (around 40%) coming to the end of 2020, but no significant finding in other countries.

CONCLUSION

The results demonstrate via mutation analysis of Orf10 can be further combined with advanced tools such as molecular simulation, artificial intelligence, and biosensors that can practically revealed for protein interactions and thus to imply the authentic Orf10 function of SARS-CoV-2 in the future.

Generation of osimertinib-resistant cells from epidermal growth factor receptor L858R/T790M mutant non-small cell lung carcinoma cell line

BACKGROUND

Lung cancer contributes to high cancer mortality worldwide with 80% of total cases diagnosed as non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) tyrosine kinase (TK) domain serves as a druggable target in NSCLC patients with exon 19 deletion and L858R mutation. However, patients eventually succumbed to resistance to first- and second-generation EGFR-TK inhibitors through activation of T790M mutation. Third-generation EGFR-TKI, Osimertinib exhibits high efficacy in patients with exon 19 deletion/L858R/T790M mutation but they experienced acquired resistance thereafter. Available treatment options in NSCLC patients remains a challenge due to unknown molecular heterogeneity responsible for acquired resistance to EGFR-TKI. In this study, we aim to generate Osimertinib-resistant (OR) cells from H1975 carrying L858R/T790M double mutation which can be used as a model to elucidate mechanism of resistance.

METHODS

OR cells were established via stepwise-dose escalation and limiting single-cell dilution method. We then evaluated Osimertinib resistance potential via cell viability assay. Proteins expression related to EGFR-signalling, epithelial to mesenchymal transition (EMT), and autophagy were analyzed via western blot.

RESULTS

OR cell lines exhibited increased drug resistance potential compared to H1975. Distinguishable mesenchymal-like features were observed in OR cells. Protein expression analysis revealed EGFR-independent signaling involved in the derived OR cells as well as EMT and autophagy activity.

CONCLUSION

We generated OR cell lines in-vitro as evidenced by increased drug resistance potential, increased mesenchymal features, and enhanced autophagy activity. Development of Osimertinib resistance cells may serve as in-vitro model facilitating discovery of molecular aberration present during acquired mechanism of resistance.

Expression of Endogenous Angiotensin-Converting Enzyme 2 in Human Induced Pluripotent Stem Cell-Derived Retinal Organoids

Angiotensin-converting enzyme 2 (ACE2) was identified as the main host cell receptor for the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its subsequent infection. In some coronavirus disease 2019 (COVID-19) patients, it has been reported that the nervous tissues and the eyes were also affected. However, evidence supporting that the retina is a target tissue for SARS-CoV-2 infection is still lacking. This present study aimed to investigate whether ACE2 expression plays a role in human retinal neurons during SARS-CoV-2 infection. Human induced pluripotent stem cell (hiPSC)-derived retinal organoids and monolayer cultures derived from dissociated retinal organoids were generated. To validate the potential entry of SARS-CoV-2 infection in the retina, we showed that hiPSC-derived retinal organoids and monolayer cultures endogenously express ACE2 and transmembrane serine protease 2 (TMPRSS2) on the mRNA level. Immunofluorescence staining confirmed the protein expression of ACE2 and TMPRSS2 in retinal organoids and monolayer cultures. Furthermore, using the SARS-CoV-2 pseudovirus spike protein with GFP expression system, we found that retinal organoids and monolayer cultures can potentially be infected by the SARS-CoV-2 pseudovirus. Collectively, our findings highlighted the potential of iPSC-derived retinal organoids as the models for ACE2 receptor-based SARS-CoV-2 infection.

Musashi-1 promotes cancer stem cell properties of glioblastoma cells via upregulation of YTHDF1

Background

Glioblastoma (GBM) is the most lethal brain tumor characterized by high morbidity and limited treatment options. Tumor malignancy is usually associated with the epigenetic marks, which coordinate gene expression to ascertain relevant phenotypes. One of such marks is m6A modification of RNA, whose functional effects are dependent on the YTH family m6A reader proteins.

Methods and results

In this study, we investigated the expression of five YTH family proteins in different GBM microarray datasets from the Oncomine database, and identified YTHDF1 as the most highly overexpressed member of this family in GBM. By performing the knockdown of YTHDF1 in a GBM cell line, we found that it positively regulates proliferation, chemoresistance and cancer stem cell-like properties. Musashi-1 (MSI1) is a postranscriptional gene expression regulator associated with high oncogenicity in GBM. By knocking down and overexpressing MSI1, we found that it positively regulates YTHDF1 expression. The inhibitory effects imposed on the processes of proliferation and migration by YTHDF1 knockdown were shown to be partially rescued by concomitant overexpression of MSI1. MSI1 and YTHDF1 were shown to be positively correlated in clinical glioma samples, and their concomitant upregulation was associated with decreased survival of glioma patients. We identified the direct regulation of YTHDF1 by MSI1.

Conclusions

Given the fact that both proteins are master regulators of gene expression, and both of them are unfavorable factors in GBM, we suggest that in any future studies aimed to uncover the prognostic value and therapy potential, these two proteins should be considered together.

Care for Patients with Stroke During the COVID-19 Pandemic: Physical Therapy and Rehabilitation Suggestions for Preventing Secondary Stroke

Infection with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the development of the novel 2019 coronavirus disease (COVID-19) and associated clinical symptoms, which typically presents as an upper respiratory syndrome such as pneumonia. Growing evidence indicates an increased prevalence of neurological involvement (e.g., in the form of stroke) during virus infection. COVID-19 has been suggested to be more than a lung infection because it affects the vasculature of the lungs and other organs and increases the risk of thrombosis. Patients with stroke are vulnerable to secondary events as a result not only of their poor vascular condition but also of their lack of access to rehabilitation resources. Herein, we review current knowledge regarding the pathophysiology of COVID-19, its possible association with neurological involvement, and current drug therapies. Suggestions are also offered regarding the potential for current neurorehabilitation therapies to be taught and practiced at home.

[Characteristics and diversity of infectious diarrheal caused by various pathogens]

Objective: To understand the characteristics and differences of diarrhea-related symptoms caused by different pathogens, and the clinical features of various pathogens causing diarrhea. Methods: Etiology surveillance program was conducted among 20 provinces of China from 2010 to 2016. The acute diarrhea outpatients were collected from clinics or hospitals. A questionnaire was used to survey demographics and clinical features. VFeces samples were taken for laboratory detection of 22 common diarrhea pathogens, to detect and analyze the clinical symptom pattern characteristics of the patient's. Results: A total of 38 950 outpatients were enrolled from 20 provinces of China. The positive rates of Rotavirus and Norovirus were the highest among the five diarrhea-causing viruses (Rotavirus: 18.29%, Norovirus: 13.06%). In the isolation and culture of 17 diarrhea-causing bacterial, Escherichia coli showed the highest positive rates (6.25%). The clinical features of bacterial diarrhea and viral diarrhea were mainly reflected in the results of fecal traits and routine examination, but pathogenic Vibrio infection was similar to viral diarrhea. Conclusion: Infectious diarrhea presents different characteristics due to various symptoms which can provide a basis for clinical diagnosis.

Pharmacological development of the potential adjuvant therapeutic agents against coronavirus disease 2019

As the coronavirus disease 2019 (COVID-19, also called severe acute respiratory syndrome coronavirus-2) outbreak accelerates, vigorous and diverse efforts were made in developing treatment strategies. In addition to direct acting agents, increasing evidence showed some potential adjuvant therapies with promising efficacy against COVID-19. These therapies include immunomodulators (i.e. intravenous immunoglobulin, thymosin α-1, interleukin [IL]-6, tocilizumab, cyclosporine, thalidomide, fingolimod), Chinese medicines (i.e. glycyrrhizin, baicalin, Xuebijing), anti-vascular endothelial growth factors (bevacizumab), estrogen modulating drugs, statins, and nutritional supplements (i.e. vitamins A, B, C, D, E and zinc). This article reviewed the pharmacological development of potential adjuvants for COVID-19 treatment.

Judicious use of sodium-glucose cotransporter 2 inhibitors in patients with diabetes on coronavirus-19 pandemic

Sodium glucose cotransporter-2 inhibitors (SGLT2i), a novel antidiabetic drug blocks the reabsorption of glucose in proximal tubules of kidney, are demonstrated to have cardiovascular and renal benefits for people with diabetes. The benefits are associated with the significant increase of intrarenal angiotensin-converting enzyme II (ACE2) expression and blood volume contraction. However, the increased ACE2 may be detrimental to patients infected with the coronavirus infection 2019 (COVID-19), which is found to invade cells via the entry receptor of ACE2. Besides, an SGLT2i-induced natriuretic effect may also increase the risk of acute kidney injury and affect the hemodynamic stability during systemic infection disease. In this article, we explain the mechanisms why the use of SGLT2i in people with diabetes may lead to worse outcomes and suggest clinician to judiciously use it during COVID-19 pandemic.

The pharmacological development of direct acting agents for emerging needed therapy against severe acute respiratory syndrome coronavirus-2

Recently, the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was quickly identified as the causal pathogen leading to the outbreak of SARS-like illness all over the world. As the SARS-CoV-2 infection pandemic proceeds, many efforts are being dedicated to the development of diverse treatment strategies. Increasing evidence showed potential therapeutic agents directly acting against SARS-CoV-2 virus, such as interferon, RNA-dependent RNA polymerase inhibitors, protease inhibitors, viral entry blockers, neuraminidase inhibitor, vaccine, antibody agent targeting the SARS-CoV-2 RNA genome, natural killer cells, and nucleocytoplasmic trafficking inhibitor. To date, several direct anti-SARS-CoV-2 agents have demonstrated promising in vitro and clinical efficacy. This article reviews the current and future development of direct acting agents against SARS-CoV-2.

Genomic variance of Open Reading Frames (ORFs) and Spike protein in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)

BACKGROUND

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused severe pneumonia at December 2019. Since then, it has been wildly spread from Wuhan, China, to Asia, European, and United States to become the pandemic worldwide. Now coronavirus disease 2019 were globally diagnosed over 3 084 740 cases with mortality of 212 561 toll. Current reports variants are found in SARS-CoV-2, majoring in functional ribonucleic acid (RNA) to transcribe into structural proteins as transmembrane spike (S) glycoprotein and the nucleocapsid (N) protein holds the virus RNA genome; the envelope (E) and membrane (M) alone with spike protein form viral envelope. The nonstructural RNA genome includes ORF1ab, ORF3, ORF6, 7a, 8, and ORF10 with highly conserved information for genome synthesis and replication in ORF1ab.

METHODS

We apply genomic alignment analysis to observe SARS-CoV-2 sequences from GenBank (http://www.ncbi.nim.nih.gov/genebank/): MN 908947 (China, C1); MN985325 (United States: WA, UW); MN996527 (China, C2); MT007544 (Australia: Victoria, A1); MT027064 (United States: CA, UC); MT039890 (South Korea, K1); MT066175 (Taiwan, T1); MT066176 (Taiwan, T2); LC528232 (Japan, J1); and LC528233 (Japan, J2) and Global Initiative on Sharing All Influenza Data database (https://www.gisaid.org). We adopt Multiple Sequence Alignments web from Clustalw (https://www.genome.jp/tools-bin/clustalw) and Geneious web (https://www.geneious.com.

RESULTS

We analyze database by genome alignment search for nonstructural ORFs and structural E, M, N, and S proteins. Mutations in ORF1ab, ORF3, and ORF6 are observed; specific variants in spike region are detected.

CONCLUSION

We perform genomic analysis and comparative multiple sequence of SARS-CoV-2. Large scaling sequence alignments trace to localize and catch different mutant strains in United possibly to transmit severe deadly threat to humans. Studies about the biological symptom of SARS-CoV-2 in clinic animal and humans will be applied and manipulated to find mechanisms and shield the light for understanding the origin of pandemic crisis.