[Survey on the awareness rate of mpox knowledge and related factors among men who have sex with men in China]

Objective: To understand the awareness rate of mpox knowledge and related factors among men who have sex with men (MSM) in China. Methods: The survey was conducted among men aged ≥18 years who had sex with men in the past year, using the convenience sampling method. The estimated sample size was 4 312. With the assistance of social organizations of MSM in 30 provinces in China, an online questionnaire survey was conducted using anonymous self-designed questionnaires powered by www.wjx.cn during 10-14 August 2023 to collect information on socio-demographic characteristics, awareness of mpox knowledge, travel history, and sexual behaviors of the respondents. The software SAS 9.4 was used for statistical analysis. Results: There were 7 725 respondents, and the age of the respondents was (31.6±9.0) years. The results revealed that the awareness rate of mpox knowledge was 50.1% (3 872/7 725). The main routes to acquire mpox knowledge were mainly new media, including WeChat, Weibo, TikTok, and Blued social software (88.4%,6 827/7 725), while official media report was the most trusted way to acquire related knowledge (79.3%,6 129/7 725). Multivariate logistic regression analysis revealed that the factors indicated a higher awareness rate of mpox knowledge, including living in the western region or the eastern region, people were over 26 years old in early adulthood and midlife, college-educated or with higher degrees, living in towns or urban periphery, being in homosexual or in bisexual relationships, 1-5 homosexual times/months in the past 3 months, knowing their HIV infection status, paying attention to mpox knowledge very often, occasionally or rarely, and convenient ways to acquire mpox knowledge from new media and social organizations. Conclusions: The awareness rate of mpox knowledge was low among MSM in China. Efforts should be made to improve the awareness rate of mpox knowledge among those who are young, less educated, or sexually active, with targeted health education via new media and social organizations.

Association of blood heavy metal concentrations with hearing loss: a systematic review and meta-analysis

OBJECTIVES

This study aimed to assess the associations between blood heavy metal concentrations and hearing loss.

STUDY DESIGN

This was a systematic review and meta-analysis.

METHODS

A comprehensive literature search was performed using Embase, PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Chinese Biomedical Literature, Wanfang and Weipu databases. Ten studies were included, and a random or fixed-effects model was used for the meta-analysis. Review Manager 5.4 software was used for data synthesis, and Stata 15.1 software was used for the publication bias and sensitivity analyses.

RESULTS

Blood lead concentrations were significantly and substantially associated with hearing loss (mean difference (MD) = 1.14; 95% confidence interval [CI] = 0.03, 2.26; P = 0.04; I2 = 81%), and iron deficiency was significantly related to hearing loss (MD = -0.42; 95% CI = -0.66, -0.18; P = 0.12; I2 = 60%).

CONCLUSIONS

These results suggest an association between blood heavy metal concentrations and hearing loss. However, there were limitations: confounding factors, lack of description for the specific methods of blinding and independent verification of case definition, limited sample size, Chinese publications comprising half of the primary data and the lack of assessment of the relationship between different blood heavy metal concentrations and the severity of hearing loss. Therefore, larger and well-designed prospective cohort studies are required for further exploration.

Fe65-engineered neuronal exosomes encapsulating corynoxine-B ameliorate cognition and pathology of Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the predominant impairment of neurons in the hippocampus and the formation of amyloid plaques, hyperphosphorylated tau protein, and neurofibrillary tangles in the brain. The overexpression of amyloid-β precursor protein (APP) in an AD brain results in the binding of APP intracellular domain (AICD) to Fe65 protein via the C-terminal Fe65-PTB2 interaction, which then triggers the secretion of amyloid-β and the consequent pathogenesis of AD. Apparently, targeting the interaction between APP and Fe65 can offer a promising therapeutic approach for AD. Recently, exosome, a type of extracellular vesicle with diameter around 30-200 nm, has gained much attention as a potential delivery tool for brain diseases, including AD, due to their ability to cross the blood-brain barrier, their efficient uptake by autologous cells, and their ability to be surface-modified with target-specific receptor ligands. Here, the engineering of hippocampus neuron cell-derived exosomes to overexpress Fe65, enabled the development of a novel exosome-based targeted drug delivery system, which carried Corynoxine-B (Cory-B, an autophagy inducer) to the APP overexpressed-neuron cells in the brain of AD mice. The Fe65-engineered HT22 hippocampus neuron cell-derived exosomes (Fe65-EXO) loaded with Cory-B (Fe65-EXO-Cory-B) hijacked the signaling and blocked the natural interaction between Fe65 and APP, enabling APP-targeted delivery of Cory-B. Notably, Fe65-EXO-Cory-B induced autophagy in APP-expressing neuronal cells, leading to amelioration of the cognitive decline and pathogenesis in AD mice, demonstrating the potential of Fe65-EXO-Cory-B as an effective therapeutic intervention for AD.

FORMATION OF MALIGNANT, METASTATIC SMALL CELL LUNG CANCERS THROUGH OVERPRODUCTION OF cMYC PROTEIN IN TP53 AND RB1 DEPLETED PULMONARY NEUROENDOCRINE CELLS DERIVED FROM HUMAN EMBRYONIC STEM CELLS

We recently described our initial efforts to develop a model for small cell lung cancer (SCLC) derived from human embryonic stem cells (hESCs) that were differentiated to form pulmonary neuroendocrine cells (PNECs), a putative cell of origin for neuroendocrine-positive SCLC. Although reduced expression of the tumor suppressor genes TP53 and RB1 allowed the induced PNECs to form subcutaneous growths in immune-deficient mice, the tumors did not display the aggressive characteristics of SCLC seen in human patients. Here we report that the additional, doxycycline-regulated expression of a transgene encoding wild-type or mutant cMYC protein promotes rapid growth, invasion, and metastasis of these hESC-derived cells after injection into the renal capsule. Similar to others, we find that the addition of cMYC encourages the formation of the SCLC-N subtype, marked by high levels of NEUROD1 RNA. Using paired primary and metastatic samples for RNA sequencing, we observe that the subtype of SCLC does not change upon metastatic spread and that production of NEUROD1 is maintained. We also describe histological features of these malignant, SCLC-like tumors derived from hESCs and discuss potential uses of this model in efforts to control and better understand this recalcitrant neoplasm.

[Epidemiological characteristics and spatio-temporal distribution of pulmonary tuberculosis cases reported in students from Guizhou Province, 2011-2020]

Objective: To analyze the trend of epidemiological characteristics and spatiotemporal distribution of pulmonary tuberculosis (PTB) among smear-positive or other types of students in Guizhou Province from 2011 to 2020, and to provide a reference for improving prevention and control measures. Methods: Data were collected from the Chinese Information System's Notifiable Disease and Tuberculosis Management Information System for disease control and prevention, the Joinpoint 4.9.1.0 software was used to analyze the trend of registration rate; the ArcGIS 10.6 software was used to construct a ring map and to perform spatial autocorrelation analysis; the SaTScan 9.7 software was used for spatial-temporal scan statistics. Results: A total of 32 682 student PTB cases were reported in Guizhou Province from 2011 to 2020, including 5 949 (18.20%) smear-positive cases. Most cases occurred from high school students of 16 to 18 years old (43.99%, 14 376/32 682); the annual average registered rate was 36.22/100 000, the highest in 2018 (52.90/100 000), and the registration rate showed an increasing trend. Meanwhile, a similar trend of registration rate was observed among smear-positive or other types of students. The spatialtemporal heterogeneity was found that the "high-high" clustering patterns of smear-positive or other types were aggregated in Bijie City. Six spatialtemporal clusters with statistically significant (all P<0.001) were detected among smear-positive or other cases, respectively. Conclusions: Upward trend with spatial- temporal clusters of PTB cases reported in students from Guizhou Province from 2011 to 2020. Surveillance should be strengthened for high school students, and regular screening should be conducted in high-risk areas to control the source of infection and reduce the risk of transmission.

[Discussion on two common problems in renal transplantation donor-specificity discrimination of anti-human leukocyte antigen antibody]

Antibody-mediated rejection (AMR) is a key factor affecting the long-term survival of renal allografts. Donor-specific antibody (DSA) is the etiology of AMR. So it is very important to accurately detect DSA. The single antigen bead (SAB) method, which is widely used in clinical practice, is prone to miss DSA detection and underestimate its mean fluorescence intensity (MFI). In this paper, the probability of missed detection of two SAB reagents was calculated by comparing common HLA alleles in China population, and the in vitro effect of antibody cross reaction on MFI value of DSA was revealed. The authors emphasized the clinical significance of the above two problems, tried to manage them by using functional epitope (eplet) analysis and give some clinical examples. Finally, the limitations of this correction method were analyzed.

Exploring the expression and potential function of follicle stimulating hormone receptor in extragonadal cells related to abdominal aortic aneurysm

INTRODUCTION

Follicle stimulating hormone (FSH) is identified to play a role in postmenopausal disease and hypothesized to affect abdominal aortic aneurysm (AAA) onset/progression in postmenopausal women. We aimed to detect FSHR gene expression in AAA tissue and cell types involved in AAA formation.

METHODS

FSH stimulation of human umbilical cord endothelial cells (HUVECs), smooth muscle cells (HUCs) and PMA-differentiated macrophages to assess gene expression of FSHR and various markers. Human macrophages activated with various stimuli were assessed for FSHR gene expression. AAA dataset, AAA tissue samples and AAA-derived smooth muscle cells (SMC) obtained from elderly female donors were assessed for FSHR gene expression. AAA-SMCs were stimulated with FSH to assess its effect on gene expression. Lastly, oxidized low-density-lipoprotein (ox-LDL) uptake and abundance of cell surface protein markers were assessed by flow cytometry after FSH stimulation of human monocytes.

RESULTS

FSH stimulation showed similar levels of gene expression in HUVECs and HUCs. Only ACTA2 was downregulated in HUCs. In PMA-differentiated macrophages, gene expression of inflammation markers was unchanged after FSH stimulation. FSHR gene expression was found to be low in the AAA datasets. Female AAA-SMCs show occasional FSHR gene expression at a very low level, yet stimulation with FSH did not affect gene expression of SMC- or inflammation markers. FSH stimulation did not impact ox-LDL uptake or alter cell surface protein expression in monocytes. While FSHR gene expression was detected in human testis tissue, it was below quantification level in all other investigated cell types, even upon activation of macrophages with various stimuli.

CONCLUSION

Despite previous reports, we did not detect FSHR gene expression in various extragonadal cell types, except in occasional female AAA-SMCs. No clear effect on cell activation was observed upon FSH stimulation in any cell type. Our data suggest that a direct effect of FSH in AAA-related extragonadal cells is unlikely to influence AAA.

[Progress in research of knowledge, attitude and practice of pre-exposure prophylaxis in men who have sex with men and its influencing factors]

Men who have sex with men (MSM) is a group of people at high risk for HIV infection in China, Pre-exposure prophylaxis (PrEP) is a bioprophylaxis strategy in the prevention of HIV infection in MSM, which can reduce the risk for HIV infection in this population effectively. However, in the paractice, the use level of PrEP in MSM is low in China, and there are MSM who know PrEP but receive no PrEP. This paper summarizes the current status of the awareness, willingness to use, actual use of PrEP in MSM and influencing factors both at home and abroad to provide a reference for the promotion of PrEP use in MSM in China.

[Safety and efficacy of a new domestic distal perforated stent graft in the treatment of Stanford type B aortic dissection]

Objective: To evaluate the safety and efficacy of a new domestic distal perforated stent graft (Talos stent) in the treatment of Stanford type B aortic dissection (TBAD). Methods: Twenty-five patients with TBAD treated with Talos stent in Yan'an Hospital Affiliated to Kunming Medical University from February 2018 to December 2019 were selected as the research subjects. Intraoperative angiography was performed to determine the number of branch arteries that remained after stent release. On postoperative day 5 (POD5), the pain intensity of the patients was evaluated by visual analog scale (VAS). The computed tomography angiography (CTA) of the patients before operation, 6 months and 12 months after operation were compared including aortic diameter, true lumen diameter, and false lumen diameter at the level of tracheal bifurcation. Follow-up was performed 1 month, 6 months, 12 months, and 24 months after surgery, and the occurrence of stent-related adverse events, reoperation and survival rate were recorded. Results: The enrolled patients included 19 males and 6 females, aged (52.6±11.1) years. Intraoperative angiography showed that 4 (1, 7) branch arteries were preserved, and the VAS score was 1 (0, 1) on POD5. The aortic diameters at the level of the tracheal bifurcation were (34.9±1.1) mm, (34.6±0.9) mm and (34.8±1.0) mm before surgery, 6 months and 12 months after surgery, and there was no significant difference (P=0.926); the diameters of the main true lumen at the level of the tracheal bifurcation were (13.3±1.6) mm, (21.8±1.0) mm and (22.3±1.1) mm before surgery, 6 months and 12 months postoperatively, while the diameters of the main false lumen at the level of the tracheal bifurcation were (20.8±2.2) mm, (4.5±1.5) mm, and (4.6±1.7) mm, respectively. Compared with before surgery, the diameter of true lumen increased significantly 6 months and 12 months after surgery (both P<0.001), while the diameter of false lumen decreased (both P<0.001). No stent-related adverse events occurred within 30 days after surgery, no secondary operations occurred within 12 months after surgery, no type Ⅰ and type Ⅲ endoleaks, no deaths or cases of paraplegia were reported, and the stent structure and position remained good. There were no deaths or paraplegia cases 24 months postoperatively, and no stent-related adverse events occurred. Conclusion: Using Talos stent in the treatment of TBAD can effectively help remodel the aorta, while preserve the intercostal artery and spinal artery, with good clinical effect and safety.

[Altered dynamics of brain spontaneous activity in betel quid dependence chewers]

Objective: To investigate the dynamic characteristics of brain spontaneous activity in betel quid dependence (BQD) chewers and its relationship with clinical indexes. Method: This study was conducted in Hainan General Hospital from April to December 2019 and the data of 53 BQD chewers (37 males and 16 females, aged 20 to 58(38±11) years) and 37 healthy controls (HC) (24 males and 13 females, aged 23-57(42±12) years) were collected. All these subjects underwent resting-state functional magnetic resonance imaging (rs-fMRI) scan. The dynamic characteristics of resting fMRI indexes, including dynamic amplitude of low-frequency fluctuations (ALFF), regional homogeneity (ReHo) and degree centrality (DC) of these subjects were calculated using the sliding time window method, parameters such as age and dynamic local consistency were analyzed and compared between the two groups. Pearson correlation was used to analyze the relationship between dynamic indexes, betel quid dependence score (BQDS) and disease duration in BQD group. Results: BQD chewers showed decreased dynamic ALFF in the left orbital prefrontal cortex (0.138±0.041 vs 0.171±0.070), the right temporal pole superior temporal gyrus (0.277±0.070 vs 0.319±0.086) and the right inferior parietal lobule (0.223±0.052 vs 0.259±0.088) than HC (all P<0.05). For regional homogeneity, BQD chewers showed a decrease dynamic ReHo in the right inferior temporal gyrus (0.055±0.008 vs 0.061±0.009), the orbital prefrontal cortex (0.058±0.005 vs 0.063±0.008), the right inferior frontal gyrus (0.081±0.006 vs 0.087±0.011), the right superior occipital gyrus (0.056±0.007 vs 0.062±0.008), the left precentral gyrus (0.068±0.008 vs 0.074±0.008), and the left superior frontal gyrus (0.058±0.008 vs 0.064±0.009) than HC (all P<0.05). BQD chewers showed an increase dynamic ReHo in the right precuneus (0.095±0.009 vs 0.089±0.008) (P<0.05). There was no significant difference in DC between the two groups (all P>0.05). The relationships between three dynamic ALFF and BQDS (r=-0.104, -0.015, -0.119), seven dynamic ReHo and BQDS (r=-0.099, -0.141, -0.055, -0.078, -0.027, -0.111, -0.090), three dynamic ALFF and disease duration (r=-0.122, -0.095, -0.171), and seven dynamic ReHo and disease duration (r=0.242, -0.252, 0.035, 0.056, 0.047, 0.081, 0.169) were not statistically significant (all P>0.05). Conclusions: BQD chewers showed a decrease dynamic ReHo and/or ALFF in multiple brain regions dominated by prefrontal cortex, and an increase dynamic ReHo in the right precuneus.

Ring Finger Protein 125 Is an Anti-Proliferative Tumor Suppressor in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the deadliest cancers worldwide and the only cancer with an increasing incidence in the United States. Recent advances in sequencing technology have enabled detailed profiling of liver cancer genomes and revealed extensive inter- and intra-tumor heterogeneity, making it difficult to identify driver genes for HCC. To identify HCC driver genes, we performed transposon mutagenesis screens in a mouse HBV model of HCC and discovered many candidate cancer genes (SB/HBV-CCGs). Here, we show that one of these genes, RNF125 is a potent anti-proliferative tumor suppressor gene in HCC. RNF125 is one of nine CCGs whose expression was >3-fold downregulated in human HCC. Depletion of RNF125 in immortalized mouse liver cells led to tumor formation in transplanted mice and accelerated growth of human liver cancer cell lines, while its overexpression inhibited their growth, demonstrating the tumor-suppressive function of RNF125 in mouse and human liver. Whole-transcriptome analysis revealed that RNF125 transcriptionally suppresses multiple genes involved in cell proliferation and/or liver regeneration, including Egfr, Met, and Il6r. Blocking Egfr or Met pathway expression inhibited the increased cell proliferation observed in RNF125 knockdown cells. In HCC patients, low expression levels of RNF125 were correlated with poor prognosis demonstrating an important role for RNF125 in HCC. Collectively, our results identify RNF125 as a novel anti-proliferative tumor suppressor in HCC.

Differential effects of macrophage subtypes on SARS-CoV-2 infection in a human pluripotent stem cell-derived model

Dysfunctional immune responses contribute critically to the progression of Coronavirus Disease-2019 (COVID-19), with macrophages as one of the main cell types involved. It is urgent to understand the interactions among permissive cells, macrophages, and the SARS-CoV-2 virus, thereby offering important insights into effective therapeutic strategies. Here, we establish a lung and macrophage co-culture system derived from human pluripotent stem cells (hPSCs), modeling the host-pathogen interaction in SARS-CoV-2 infection. We find that both classically polarized macrophages (M1) and alternatively polarized macrophages (M2) have inhibitory effects on SARS-CoV-2 infection. However, M1 and non-activated (M0) macrophages, but not M2 macrophages, significantly up-regulate inflammatory factors upon viral infection. Moreover, M1 macrophages suppress the growth and enhance apoptosis of lung cells. Inhibition of viral entry using an ACE2 blocking antibody substantially enhances the activity of M2 macrophages. Our studies indicate differential immune response patterns in distinct macrophage phenotypes, which could lead to a range of COVID-19 disease severity.

[Spindle cell hemangioma: a clinicopathological and molecular analysis of eight cases]

Objective: To investigate the clinicopathological and genetic characteristics of spindle cell hemangioma (SCH). Methods: The clinical, morphological and immunohistochemical features of 8 SCHs diagnosed from January 2013 to September 2021 in West China Hospital, Sichuan University, Chengdu, China were retrospectively analyzed. Hotspot mutations for IDH1 codon 132 and IDH2 codon 172 were tested in 4 SCHs and 29 other non-SCH lesions using Sanger sequencing. Results: The 8 cases occurred in patients with a wide age range, from neonate to 46 years (mean 28 years, median 32 years). Both genders were equally affected. The course of the disease spanned from half a year to 31 years. Two SCHs were recurrent tumors. All tumors involved the distal extremities (4 of foot, 2 of ankle and 2 of hand). Six cases were presented as a single lesion and 2 cases as multiple lesions. The tumor diameters were 1-5 cm. All the 8 SCHs were typically composed of cavernous vascular space and solid components consisting of slit-like vessels, spindle cells and epithelioid endothelial cells which often exhibited cytoplasmic vacuolation. These two alternating components and the vacuolated epithelioid endothelial cells were the distinctive diagnostic clues for SCH. Vascular endothelial cells including epithelioid cells in the solid areas expressed CD31 (8/8), ERG (4/4), CD34 (5/8) and D2-40 (2/3). The spindle cells expressed SMA (8/8). Neither endothelial cells nor spindle cells expressed HHV8 (0/7), Desmin (0/5) or S-100 (0/3). Mutations were revealed in 2 SCHs, with IDH1 mutation (p.R132C) and IDH2 mutation (p.R172G), respectively. The IDH1/2 gene hotspot mutations were not found in the remaining 2 SCHs or the other 29 non-SCH lesions. Simple excisions were performed for 7 cases, and partial resection for 1 case. Follow-up information was obtained in 6 cases, with follow-up time ranging from 5 to 90 months (average, 46 months). No metastasis occurred in the 6 cases. No recurrence occurred in cases treated with simple excision. The residual lesions of the patient who received partial resection were stable. Conclusions: SCH is rare and should be differentiated from a variety of benign and malignant vascular lesions. An accurate diagnosis of SCH is clinically important and can be achieved by combining clinical information and typical pathological presentation. IDH1/2 gene hotspot mutations are specific to SCH in vascular lesions. Genetic detection is helpful in the diagnosis of challenging cases.

[Diagnostic value of MDM2 RNA in situ hybridization in atypical lipomatous tumor/well-differentiated liposarcoma and dedifferentiated liposarcoma]

Objective: To investigate the value of MDM2 RNA in situ hybridization (RNA-ISH) in diagnosing atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL) and dedifferentiated liposarcoma (DDL). Methods: A total of 26 ALT/WDL/DDLs diagnosed from March 2017 to May 2019 in West China Hospital, Sichuan University, Chengdu, China and 18 control cases were included. MDM2 RNA-ISH was performed on all samples and compared with the fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) regarding their performance in detecting MDM2. Results: All samples were detected successfully using the three methods. Among 26 ALT/WDL/DDLs, all cases showed MDM2 amplification and positivity for MDM2 RNA-ISH (26/26, 100%). Twenty-four (24/26, 92.3%) of the 26 tested cases were positive for MDM2 IHC while two of them were negative. Eighteen control cases were all negative for MDM2 FISH and RNA-ISH, and 15 (15/18) cases were negative for MDM2 IHC. The sensitivity and specificity of RNA-ISH were both 100%, and those of MDM2 IHC were 92.3% and 83.3%, respectively. Diffuse staining was identified in all MDM2 RNA-ISH positive ALT/WDL/DDLs, but identified in only 8/24 (33.3%) of the MDM2 IHC positive cases. Among the 11 ALT/WDL/DDL samples evaluated on tissue microarray, the positive rate of MDM2 RNA-ISH was 100% with diffuse staining in all cases. The positive rate of MDM2 IHC was 9/11 while only 1 of the 9 cases showed diffuse staining. The result of MDM2 RNA-ISH was identical to that of MDM2 FISH and was overall consistent with that of MDM2 IHC (Kappa=0.763, P<0.001). Conclusions: In ALT/WDL/DDLs, results of MDM2 RNA-ISH are highly consistent with those of FISH. MDM2 RNA-ISH is more sensitive and more specific and has more diffuse positive signals than the IHC. The findings indicate that MDM2 RNA-ISH is highly valuable for the diagnosis and differential diagnosis of ALT/WDL/DDLs.

The expression of cytokeratin and apoptosis-related molecules in echinococcosis related liver injury

The study aimed to investigate the expression of cytokeratin and apoptosis-related molecules in the livers of two types of hepatic echinococcosis mice models and to preliminarily explore the relationship between the expression of cytokeratin and apoptosis in echinococcosis related liver injury. We established a mouse model infected by Echinococcus granulosus and Echinococcus multilocularis and observed the expression of cytokeratin and apoptosis related proteins in the two types of hepatic echinococcosis tissues during different stages by immunohistochemical staining. A co-culture model was established using normal hepatocytes and different concentrations of E. granulosus and E. multilocularis protoscoleces. Cell Counting Kit-8 was used to detect cell proliferation, flow cytometry was used to detect hepatocyte apoptosis, and western blot was used to quantify cytokeratin and apoptosis-related proteins, such as caspase3, caspase9, Bcl-2, and Bax. Surgical specimens were obtained from patients with hepatic echinococcosis to analyze the expressions of cytokeratin, caspase3, caspase9, Bcl-2, and Bax by western blot. The expressions of cytokeratin and caspase3 were analyzed by immunohistochemistry. The qRT-PCR method was used to determine the expression of CK8 and CK18 in the liver tissues. In vivo experiments showed that compared to that in the control group, the cytokeratin and caspase3 proteins in the liver tissues of the two types of hepatic echinococcosis were strongly expressed around the lesions of liver echinococcosis; there was a difference between cytokeratin expression of the two different echinococcosis parasites in the liver. Echinococcus granulosus and Echinococcus multilocularis in the co-culture model in vitro could promote the expression of CK, caspase3, caspase9, and Bax protein, decrease the expression of Bcl-2, promote hepatocyte apoptosis, and inhibit cell proliferation; in clinical samples, we found that compared with that in the normal tissues, the expression of cytokeratin, caspase3, caspase9, and Bax in echinococcus tissues was high, but that in Bcl-2 was low. Furthermore, the expression of CK8 and CK18 mRNA were higher in echinococcus tissues than that in the normal tissues and immunohistochemistry analysis also showed that cytokeratin and caspase3 levels were higher in echinococcus tissues than that in the normal tissues. The expression of cytokeratin and apoptosis-related molecules, reflecting liver damage, is high in the liver and is caused due to hepatic echinococcosis. This study provides the first evidence of cytokeratin could be useful for evaluating liver tissue damage caused by echinococcus infection.

Exosomes: Small vesicles with big roles in cancer, vaccine development, and therapeutics

Cancer is a deadly disease that is globally and consistently one of the leading causes of mortality every year. Despite the availability of chemotherapy, radiotherapy, immunotherapy, and surgery, a cure for cancer has not been attained. Recently, exosomes have gained significant attention due to the therapeutic potential of their various components including proteins, lipids, nucleic acids, miRNAs, and lncRNAs. Exosomes constitute a set of tiny extracellular vesicles with an approximate diameter of 30-100 nm. They are released from different cells and are present in biofluids including blood, cerebrospinal fluid (CSF), and urine. They perform crucial multifaceted functions in the malignant progression of cancer via autocrine, paracrine, and endocrine communications. The ability of exosomes to carry different cargoes including drug and molecular information to recipient cells make them a novel tool for cancer therapeutics. In this review, we discuss the major components of exosomes and their role in cancer progression. We also review important literature about the potential role of exosomes as vaccines and delivery carriers in the context of cancer therapeutics.

[Evaluation of screening strategies of multidrug-resistant tuberculosis among pulmonary tuberculosis patients of the different risk levels]

Objective: To evaluate the detection of MDR-TB and XDR-TB patients and to provide evidence for further improvement of MDR-TB and XDR-TB screening strategy. Methods: Patients who were under drug resistance surveillance, registered and reported by the TB Management Information System of the Chinese Disease Prevention and Control Information System from 2012 to 2019 and resided in Guizhou province were retrospectively analyzed. The contribution of five high-risk subgroups to detection of MDR/XDR-TB were evaluated using population attributable risk proportion (PARP). Results: Of the 18 506 cases under drug resistance surveillance, patients who were male, aged between 25 and 54 years, with drug-resistant TB or with MDR/XDR-TB accounted for 68.65% (12 705/18 506), 47.69% (8 826/18 506), 15.90% (2 943/18 506) or 5.42% (1 003/18 506), respectively. Five high-risk subgroups made significant contributions to the detection of MDR/XDR-TB with a PARP of 57.00%. Specifically, the PARP were 21.70%, 19.49%, 11.90% and 2.30% for patients that were relapse and return, failed initial treatment, chronic/retreatment failure and smear-positive at the end of the second or third month, respectively. The detection rate of MDR/XDR-TB in high-risk groups was 15.89% (578/3 637) while in low-risk groups was 2.86% (425/14 869). Conclusions: Number of patients under drug resistance surveillance and the detection of MDR/XDR-TB trended to increase in Guizhou province from 2012 to 2019. The detection rate of MDR/XDR-TB in high-risk groups was higher than low-risk groups.

Management of adrenoleukodystrophy: From pre-clinical studies to the development of new therapies

X-linked adrenoleukodystrophy (X-ALD) is an inherited neurodegenerative disorder associated with mutations of the ABCD1 gene that encodes a peroxisomal transmembrane protein. It results in accumulation of very long chain fatty acids in tissues and body fluid. Along with other factors such as epigenetic and environmental involvement, ABCD1 mutation-provoked disorders can present different phenotypes including cerebral adrenoleukodystrophy (cALD), adrenomyeloneuropathy (AMN), and peripheral neuropathy. cALD is the most severe form that causes death in young childhood. Bone marrow transplantation and hematopoietic stem cell gene therapy are only effective when performed at an early stage of onsets in cALD. Nonetheless, current research and development of novel therapies are hampered by a lack of in-depth understanding disease pathophysiology and a lack of reliable cALD models. The Abcd1 and Abcd1/Abcd2 knock-out mouse models as well as the deficiency of Abcd1 rabbit models created in our lab, do not develop cALD phenotypes observed in human beings. In this review, we summarize the clinical and biochemical features of X-ALD, the progress of pre-clinical and clinical studies. Challenges and perspectives for future X-ALD studies are also discussed.

The mini player with diverse functions: extracellular vesicles in cell biology, disease, and therapeutics

Extracellular vesicles (EVs) are tiny biological nanovesicles ranging from approximately 30-1000 nm in diameter that are released into the extracellular matrix of most cell types and in biofluids. The classification of EVs includes exosomes, microvesicles, and apoptotic bodies, dependent on various factors such as size, markers, and biogenesis pathways. The transition of EV relevance from that of being assumed as a trash bag to be a key player in critical physiological and pathological conditions has been revolutionary in many ways. EVs have been recently revealed to play a crucial role in stem cell biology and cancer progression via intercellular communication, contributing to organ development and the progression of cancer. This review focuses on the significant research progress made so far in the role of the crosstalk between EVs and stem cells and their niche, and cellular communication among different germ layers in developmental biology. In addition, it discusses the role of EVs in cancer progression and their application as therapeutic agents or drug delivery vehicles. All such discoveries have been facilitated by tremendous technological advancements in EV-associated research, especially the microfluidics systems. Their pros and cons in the context of characterization of EVs are also extensively discussed in this review. This review also deliberates the role of EVs in normal cell processes and disease conditions, and their application as a diagnostic and therapeutic tool. Finally, we propose future perspectives for EV-related research in stem cell and cancer biology.

[Nodular fasciitis of the breast: a clinicopathological and genetic analysis of seven cases]

Objective: To investigate the clinicopathological and genetic features of nodular fasciitis of the breast (NFB). Methods: The clinical and histologic features of seven NFBs were retrospectively reviewed. Immunohistochemistry, fluorescence in situ hybridization (FISH) and reverse transcription-polymerase chain reaction (RT-PCR) were performed. Results: All the seven patients were female, with a mean age of 36 years (range from 15 to 51 years). The duration of the lesion ranged from 10 days to 2 years. There was no history of trauma for all patients. The lesions occurred in the upper quadrant (4 cases), the lower quadrant (2 cases) and the axillary tail region (1 case). The maximum diameter was 1.0-3.5 cm. All cases showed similar morphology as nodular fasciitis occurring elsewhere in the body. They were composed of plump spindle cells arranged in short bundles or fascicles within a loose collagenous/myxoid stroma. Erythrocyte extravasation, mixed chronic inflammatory cells infiltration and microcystic changes were typically seen. Mitoses were present, with no atypical mitoses observed. The spindle cells were positive for smooth muscleactin(SMA, 6/6), CD10(2/3), and negative for desmin, β-catenin, CD34, CKpan, EMA, S-100, p63 and ALK-1.The Ki-67 index were 5%-15%. USP6 gene rearrangement was found in six cases and MYH9-USP6 gene fusion in two cases. Local resection was performed in six cases. Spontaneous regression was observed in one case. Follow-up of all seven cases revealed no recurrence or metastasis. Conclusions: Although rare, NFB can mimic breast cancer clinically, radiologically and histologically. It should be always considered in the differential diagnosis for the spindle cell proliferations of the breast. A diagnosis of NFB can be achieved basing on the typical clinicopathological presentation. FISH detection of USP6 gene rearrangement in challenging cases is of great value.

Distinct disease severity between children and older adults with COVID-19: Impacts of ACE2 expression, distribution, and lung progenitor cells

BACKGROUND

Children and older adults with coronavirus disease 2019 (COVID-19) display a distinct spectrum of disease severity yet the risk factors aren't well understood. We sought to examine the expression pattern of angiotensin-converting enzyme 2 (ACE2), the cell-entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the role of lung progenitor cells in children and older patients.

METHODS

We retrospectively analysed clinical features in a cohort of 299 patients with COVID-19. The expression and distribution of ACE2 and lung progenitor cells were systematically examined using a combination of public single-cell RNA-seq datasets, lung biopsies, and ex vivo infection of lung tissues with SARS-CoV-2 pseudovirus in children and older adults. We also followed up patients who had recovered from COVID-19.

RESULTS

Compared with children, older patients (> 50 yrs.) were more likely to develop into serious pneumonia with reduced lymphocytes and aberrant inflammatory response (p = 0.001). The expression level of ACE2 and lung progenitor cell markers were generally decreased in older patients. Notably, ACE2 positive cells were mainly distributed in the alveolar region, including SFTPC positive cells, but rarely in airway regions in the older adults (p < 0.01). The follow-up of discharged patients revealed a prolonged recovery from pneumonia in the older (p < 0.025).

CONCLUSION

Compared to children, ACE2 positive cells are generally decreased in older adults and mainly presented in the lower pulmonary tract. The lung progenitor cells are also decreased. These risk factors may impact disease severity and recovery from pneumonia caused by SARS-Cov-2 infection in older patients.

Identification of SARS-CoV-2 inhibitors using lung and colonic organoids

There is an urgent need to create novel models using human disease-relevant cells to study severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) biology and to facilitate drug screening. Here, as SARS-CoV-2 primarily infects the respiratory tract, we developed a lung organoid model using human pluripotent stem cells (hPSC-LOs). The hPSC-LOs (particularly alveolar type-II-like cells) are permissive to SARS-CoV-2 infection, and showed robust induction of chemokines following SARS-CoV-2 infection, similar to what is seen in patients with COVID-19. Nearly 25% of these patients also have gastrointestinal manifestations, which are associated with worse COVID-19 outcomes1. We therefore also generated complementary hPSC-derived colonic organoids (hPSC-COs) to explore the response of colonic cells to SARS-CoV-2 infection. We found that multiple colonic cell types, especially enterocytes, express ACE2 and are permissive to SARS-CoV-2 infection. Using hPSC-LOs, we performed a high-throughput screen of drugs approved by the FDA (US Food and Drug Administration) and identified entry inhibitors of SARS-CoV-2, including imatinib, mycophenolic acid and quinacrine dihydrochloride. Treatment at physiologically relevant levels of these drugs significantly inhibited SARS-CoV-2 infection of both hPSC-LOs and hPSC-COs. Together, these data demonstrate that hPSC-LOs and hPSC-COs infected by SARS-CoV-2 can serve as disease models to study SARS-CoV-2 infection and provide a valuable resource for drug screening to identify candidate COVID-19 therapeutics.

Clinical analysis and pluripotent stem cells-based model reveal possible impacts of ACE2 and lung progenitor cells on infants vulnerable to COVID-19

Introduction: An increasing number of children with severe coronavirus disease 2019 (COVID-19) is being reported, yet the spectrum of disease severity and expression patterns of angiotensin-converting enzyme 2 (ACE2) in children at different developmental stages are largely unknow.

Methods: We analysed clinical features in a cohort of 173 children with COVID-19 (0-15 yrs.-old) between January 22, 2020 and March 15, 2020. We systematically examined the expression and distribution of ACE2 in different developmental stages of children by using a combination of children's lung biopsies, pluripotent stem cell-derived lung cells, RNA-sequencing profiles, and ex vivo SARS-CoV-2 pseudoviral infections.

Results: It revealed that infants (< 1yrs.-old), with a weaker potency of immune response, are more vulnerable to develop pneumonia whereas older children (> 1 yrs.-old) are more resistant to lung injury. The expression levels of ACE2 however do not vary by age in children's lung. ACE2 is notably expressed not only in Alveolar Type II (AT II) cells, but also in SOX9 positive lung progenitor cells detected in both pluripotent stem cell derivatives and infants' lungs. The ACE2⁺SOX9⁺ cells are readily infected by SARS-CoV-2 pseudovirus and the numbers of the double positive cells are significantly decreased in older children.

Conclusions: Infants (< 1 yrs.-old) with SARS-CoV-2 infection are more vulnerable to lung injuries. ACE2 expression in multiple types of lung cells including SOX9 positive progenitor cells, in cooperation with an unestablished immune system, could be risk factors contributing to vulnerability of infants with COVID-19. There is a need to continue monitoring lung development in young children who have recovered from SARS-CoV-2 infection.

[A long-term follow-up study on the occurrence of heterotopic ossification after artificial cervical disc replacement with Discover disc]

Objective: To analyze the incidence of heterotopic ossification after artificial cervical disc replacement with Discover disc, and to explore the effect of heterotopic ossification on postoperative radiological and clinical efficacy. Methods: From January 2010 to January 2015, 45 patients with cervical spondylosis underwent single-level artificial cervical disc replacement in Shanghai Changzheng Hospital, including 29 cases of cervical spondylotic myelopathy, 11 cases of cervical spondylotic radiculopathy and 5 cases of mixed cervical spondylosis. At the last follow-up, Mehren grading method was used for classification of heterotopic ossification, among which, grade 0-Ⅱ was defined as low grade ossification group, and 26 patients (16 male, 10 female) were enrolled in this group; grade Ⅲ-Ⅳ was defined as high grade ossification group, and 19 patients (12 males, 7 females) were included in this group. C(2-7) Cobb angle, cervical total range of motion and range of motion at index level were used to evaluate the radiological outcomes of the two groups. Japanese Orthopaedic Association (JOA) score, neck disability index (NDI) score and visual analogue scale (VAS) were used to evaluate the clinical outcomes of the two groups. The adjacent segment intervertebral disc height and range of motion were used to evaluate the effects of heterotopic ossification on adjacent segment. Results: All patients were followed up regularly for (98±18) months. There were no statistical differences between the two groups regarding to demographic data (all P>0.05). There was no significant differences in C(2-7) Cobb angle and total range of motion between the two groups at the last follow-up (all P>0.05), but range of motion at index level in the group with low grades was significantly higher than that in the group with high grades (7.8°±6.2° vs 2.6°±1.2°, t=3.60, P<0.05). There was no significant differences in JOA score, recovery rate and NDI score between the two groups (all P>0.05). There was no significant differences in the adjacent segment intervertebral disc height before operation and at the last follow-up (both P>0.05). There was no significant differences in range of motion at adjacent segment before operation (P>0.05), while range of motion at adjacent segment in the group with low grades was significantly lower than that in the group with high grades (9.5°±1.1° vs 10.6°±1.8° and 9.4°±1.4° vs 10.5°±1.7°, repectively, t=2.54, 2.31, both P<0.05). Conclusions: Heterotopic ossification does not affect the clinical outcomes, cervical curvature and cervical total range of motion after artificial cervical disc replacement with Discover disc. However, the higher grade of heterotopic ossification, the lower range of motion at index level and the higher range of motion at adjacent segment.

Human pluripotent stem cell-derived lung organoids: Potential applications in development and disease modeling

The pulmonary system is comprised of two main compartments, airways and alveolar space. Their tissue and cellular complexity ensure lung function and protection from external agents, for example, virus. Two-dimensional (2D) in vitro systems and animal models have been largely employed to elucidate the molecular mechanisms underlying human lung development, physiology, and pathogenesis. However, neither of these models accurately recapitulate the human lung environment and cellular crosstalk. More recently, human-derived three-dimensional (3D) models have been generated allowing for a deeper understanding of cell-to-cell communication. However, the availability and accessibility of primary human cell sources from which generate the 2D and 3D models may be limited. In the past few years, protocols have been developed to successfully employ human pluripotent stem cells (hPSCs) and differentiate them toward pulmonary fate in vitro. In the present review, we discuss the advantages and pitfalls of hPSC-derived lung 2D and 3D models, including the main characteristics and potentials for these models and their current and future applications for modeling development and diseases. Lung organoids currently represent the closest model to the human pulmonary system. We further focus on the applications of lung organoids for the study of human diseases such as pulmonary fibrosis, infectious diseases, and lung cancer. Finally, we discuss the present limitations and potential future applications of 3D lung organoids. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cell Differentiation and Reversion.

Depth-Resolved Magnetization Dynamics Revealed by X-Ray Reflectometry Ferromagnetic Resonance

Magnetic multilayers offer diverse opportunities for the development of ultrafast functional devices through advanced interface and layer engineering. Nevertheless, a method for determining their dynamic properties as a function of depth throughout such stacks has remained elusive. By probing the ferromagnetic resonance modes with element-selective soft x-ray resonant reflectivity, we gain access to the magnetization dynamics as a function of depth. Most notably, using reflectometry ferromagnetic resonance, we find a phase lag between the coupled ferromagnetic layers in [CoFeB/MgO/Ta]_{4} multilayers that is invisible to other techniques. The use of reflectometry ferromagnetic resonance enables the time-resolved and depth-resolved probing of the complex magnetization dynamics of a wide range of functional magnetic heterostructures with absorption edges in the soft x-ray wavelength regime.

Modeling COVID-19 with Human Pluripotent Stem Cell-Derived Cells Reveals Synergistic Effects of Anti-inflammatory Macrophages with ACE2 Inhibition Against SARS-CoV-2

Dysfunctional immune responses contribute critically to the progression of Coronavirus Disease-2019 (COVID-19) from mild to severe stages including fatality, with pro-inflammatory macrophages as one of the main mediators of lung hyper-inflammation. Therefore, there is an urgent need to better understand the interactions among SARS-CoV-2 permissive cells, macrophage, and the SARS-CoV-2 virus, thereby offering important insights into new therapeutic strategies. Here, we used directed differentiation of human pluripotent stem cells (hPSCs) to establish a lung and macrophage co-culture system and model the host-pathogen interaction and immune response caused by SARS-CoV-2 infection. Among the hPSC-derived lung cells, alveolar type II and ciliated cells are the major cell populations expressing the viral receptor ACE2 and co-effector TMPRSS2, and both were highly permissive to viral infection. We found that alternatively polarized macrophages (M2) and classically polarized macrophages (M1) had similar inhibitory effects on SARS-CoV-2 infection. However, only M1 macrophages significantly up-regulated inflammatory factors including IL-6 and IL-18, inhibiting growth and enhancing apoptosis of lung cells. Inhibiting viral entry into target cells using an ACE2 blocking antibody enhanced the activity of M2 macrophages, resulting in nearly complete clearance of virus and protection of lung cells. These results suggest a potential therapeutic strategy, in that by blocking viral entrance to target cells while boosting anti-inflammatory action of macrophages at an early stage of infection, M2 macrophages can eliminate SARS-CoV-2, while sparing lung cells and suppressing the dysfunctional hyper-inflammatory response mediated by M1 macrophages.

Modeling COVID-19 with Human Pluripotent Stem Cell-Derived Cells Reveals Synergistic Effects of Anti-inflammatory Macrophages with ACE2 Inhibition Against SARS-CoV-2

Dysfunctional immune responses contribute critically to the progression of Coronavirus Disease-2019 (COVID-19) from mild to severe stages including fatality, with pro-inflammatory macrophages as one of the main mediators of lung hyper-inflammation. Therefore, there is an urgent need to better understand the interactions among SARS-CoV-2 permissive cells, macrophage, and the SARS-CoV-2 virus, thereby offering important insights into new therapeutic strategies. Here, we used directed differentiation of human pluripotent stem cells (hPSCs) to establish a lung and macrophage co-culture system and model the host-pathogen interaction and immune response caused by SARS-CoV-2 infection. Among the hPSC-derived lung cells, alveolar type II and ciliated cells are the major cell populations expressing the viral receptor ACE2 and co-effector TMPRSS2, and both were highly permissive to viral infection. We found that alternatively polarized macrophages (M2) and classically polarized macrophages (M1) had similar inhibitory effects on SARS-CoV-2 infection. However, only M1 macrophages significantly up-regulated inflammatory factors including IL-6 and IL-18, inhibiting growth and enhancing apoptosis of lung cells. Inhibiting viral entry into target cells using an ACE2 blocking antibody enhanced the activity of M2 macrophages, resulting in nearly complete clearance of virus and protection of lung cells. These results suggest a potential therapeutic strategy, in that by blocking viral entrance to target cells while boosting anti-inflammatory action of macrophages at an early stage of infection, M2 macrophages can eliminate SARS-CoV-2, while sparing lung cells and suppressing the dysfunctional hyper-inflammatory response mediated by M1 macrophages.

A Human Pluripotent Stem Cell-based Platform to Study SARS-CoV-2 Tropism and Model Virus Infection in Human Cells and Organoids

SARS-CoV-2 has caused the COVID-19 pandemic. There is an urgent need for physiological models to study SARS-CoV-2 infection using human disease-relevant cells. COVID-19 pathophysiology includes respiratory failure but involves other organ systems including gut, liver, heart, and pancreas. We present an experimental platform comprised of cell and organoid derivatives from human pluripotent stem cells (hPSCs). A Spike-enabled pseudo-entry virus infects pancreatic endocrine cells, liver organoids, cardiomyocytes, and dopaminergic neurons. Recent clinical studies show a strong association with COVID-19 and diabetes. We find that human pancreatic beta cells and liver organoids are highly permissive to SARS-CoV-2 infection, further validated using adult primary human islets and adult hepatocyte and cholangiocyte organoids. SARS-CoV-2 infection caused striking expression of chemokines, as also seen in primary human COVID-19 pulmonary autopsy samples. hPSC-derived cells/organoids provide valuable models for understanding the cellular responses of human tissues to SARS-CoV-2 infection and for disease modeling of COVID-19.

Identification of Candidate COVID-19 Therapeutics using hPSC-derived Lung Organoids

The SARS-CoV-2 virus has caused already over 3.5 million COVID-19 cases and 250,000 deaths globally. There is an urgent need to create novel models to study SARS-CoV-2 using human disease-relevant cells to understand key features of virus biology and facilitate drug screening. As primary SARS-CoV-2 infection is respiratory-based, we developed a lung organoid model using human pluripotent stem cells (hPSCs) that could be adapted for drug screens. The lung organoids, particularly aveolar type II cells, express ACE2 and are permissive to SARS-CoV-2 infection. Transcriptomic analysis following SARS-CoV-2 infection revealed a robust induction of chemokines and cytokines with little type I/III interferon signaling, similar to that observed amongst human COVID-19 pulmonary infections. We performed a high throughput screen using hPSC-derived lung organoids and identified FDA-approved drug candidates, including imatinib and mycophenolic acid, as inhibitors of SARS-CoV-2 entry. Pre- or post-treatment with these drugs at physiologically relevant levels decreased SARS-CoV-2 infection of hPSC-derived lung organoids. Together, these data demonstrate that hPSC-derived lung cells infected by SARS-CoV-2 can model human COVID-19 disease and provide a valuable resource to screen for FDA-approved drugs that might be repurposed and should be considered for COVID-19 clinical trials.

[Clinical study of psychological changes and post traumatic stress disorder in elderly patients with hip fracture]

Objective: To explore the psychological state and affected factors of elderly patients with hip fractures. Methods: A retrospective analysis of 156 elderly hip fracture patients(>65 years) admitted to the Department of Orthopaedics, the First Affiliated Hospital of Harbin Medical University from January 2016 to August 2019 was performed. General and psychological information were collected by questionnaire.General information included age, gender, education, whether surgery, length of stay.SCL-90, a self-assessment scale, was chosen as the psychological test to analyzed the elderly hip fracture patients' psychological status during hospitalization and the norms of SCL-90 in Chinese which were established in 1986 were used as the control group. The prognostic factors were examined by univariate and multivariate analysis. Results: Somatization, interpersonal sensitivity, depression, anxiety, paranoid factor scores, and total scores of the elderly hip fracture patients were significantly higher than control group(all P=0.00).Univariate analysis and logistic regression analysis showed that non-surgery treatment and more than 10 days of hospitalization were independent prognostic factors that affected the psychological state of elderly hip fracture patients (all P=0.00). Conclusion: Elderly patients hospitalized with osteoporosis and hip fractures are prone to have negative emotional and psychological changes.The length of hospitalization and the choice of treatment can affect patients' psychological state, suggesting that effective psychological intervention is necessary.

[Overexpression of protein phosphatase 2 regulatory subunit B''α gene effect on proliferation and invasion of hepatoma cells]

Objective: To study the overexpression of protein phosphatase 2 regulatory subunit B''α gene effects on the proliferation and invasion of hepatoma cells. Methods: Immunohistochemistry method was used to analyze the expression of PPP2R3A in cancerous and paracancerous tissues. Hepatocellular carcinoma cell lines (Huh-7 and HepG2) with stably overexpressing PPP2R3A were constructed by lentiviral vector. Biological behavioral transition in hepatocellular carcinoma cell proliferation, cell cycle, apoptosis, invasion and metastasis were detected by cell counting kit-8 assay (CCK-8), flow cytometry, and transwell assay. A subcutaneous nude tumor mice model was constructed to validate the growth of hepatoma cells. Two independent sample t-tests were used to compare the groups. Results: The expression of PPP2R3A gene in human hepatocarcinoma tissues was higher than paracancerous tissues. The absorbance (A value) of hepatoma cells was increased (P < 0.05) after overexpression of PPP2R3A gene. The transition from G1-to-S phase was significantly increased i.e., the G1 phase of the cell cycle was reduced (Huh-7: t = 3.04, P = 0.0384; HepG2: t = 4.06, P = 0.0153), while the S phase was increased (Huh-7: t = 3.47, P = 0.0255; HepG2: t = 4.46, P = 0.0112). Early apoptotic rate was decreased (Huh-7: t = 7.34, P = 0.0018; HepG2: t = 4.06, P = 0.0153). The number of Huh-7 cells migrating to the lower chamber was increased (t = 3.18, P = 0.0334), and after the use of matrigel the number of cells reaching to the lower chamber was also increased (t = 2.84, P = 0.0464). The results of animal experiments showed that the subcutaneous tumor growth (t = 4.31, P = 0.0035) was significantly overexpressed in nude mice group. The results of Western blot showed that the expression of PARP and P53 protein in the spliced ​​forms decreased, while the accumulation of β-catenin protein in the liver cancer cells was increased. Conclusion: Overexpressed PPP2R3A gene may promote proliferation, migration and invasion ability, inhibit apoptosis, induce G1/S phase transition, and participate in the biological behavior of hepatoma cells.

Unique genetic profiles from cerebrospinal fluid cell-free DNA in leptomeningeal metastases of EGFR-mutant non-small-cell lung cancer: a new medium of liquid biopsy

Background

Leptomeningeal metastases (LM) are more frequent in non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations. Due to limited access to leptomeningeal lesions, the purpose of this study was to explore the potential role of cerebrospinal fluid (CSF) as a source of liquid biopsy in patients with LM.

Patients and methods

Primary tumor, CSF, and plasma in NSCLC with LM were tested by next-generation sequencing. In total, 45 patients with suspected LM underwent lumbar puncture, and those with EGFR mutations diagnosed with LM were enrolled.

Results

A total of 28 patients were enrolled in this cohort; CSF and plasma were available in 26 patients, respectively. Driver genes were detected in 100% (26/26), 84.6% (22/26), and 73.1% (19/26) of samples comprising CSF cell-free DNA (cfDNA), CSF precipitates, and plasma, respectively; 92.3% (24/26) of patients had much higher allele fractions in CSF cfDNA than the other two media. Unique genetic profiles were captured in CSF cfDNA compared with those in plasma and primary tissue. Multiple copy number variations (CNVs) were mainly identified in CSF cfDNA, and MET copy number gain identified in 47.8% (11/23) of patients was the most frequent one, while other CNVs included ERBB2, KRAS, ALK, and MYC. Moreover, loss of heterozygosity (LOH) of TP53 was identified in 73.1% (19/26) CSF cfDNA, which was much higher than that in plasma (2/26, 7.7%; P < 0.001). There was a trend towards a higher frequency of concomitant resistance mutations in patients with TP53 LOH than those without (70.6% versus 33.3%; P = 0.162). EGFR T790M was identified in CSF cfDNA of 30.4% (7/23) of patients who experienced TKI progression.

Conclusion

CSF cfDNA could reveal the unique genetic profiles of LM and should be considered as the most representative liquid biopsy medium for LM in EGFR-mutant NSCLC.

[The role of S100A8/RAGE and Caveolin-1 and the effect of roxithromycin on their expression in a rat model of neutrophilic asthma]

Objective: To explore the role of S100A8, the receptor for advanced glycation endproducts (RAGE) and Caveolin-1 in neutrophilic asthmatic rats, and to further study the intervention of roxithromycin and the possible mechanisms. Methods: Male Brown Norway rats were randomly assigned to a control group, an asthma group and a Roxithromycin group. The asthmatic rat model was established by intraperitoneal injection of ovalbumin (OVA) and Freund's complete adjuvant (FCA) mixture, and aerosol inhalation of OVA. Rats in the Roxithromycin group were given roxithromycin injection 30 mg/kg 30 minutes before each challenge. Rats in the control and the asthma groups were replaced with equal volumes of saline, respectively. Bronchoalveolar lavage fluid (BALF) neutrophil percentage (Neu%) and pathological changes of pulmonary tissue (hematoxylin-eosin, HE staining) were measured to confirm the establishment of asthmatic models. The concentration of inflammatory cytokines and S100A8 were quantified by enzyme-linked immunosorbent assay (ELISA), and the expression of Caveolin-1 and RAGE at protein levels were detected by immunohistochemistry and Western blot. Results: Neu% in BALF of the asthma group was significantly higher than those of the control group, and Neu% in the Roxithromycin group was lower than the asthma group (all P<0.01). Pulmonary histology revealed that there were a large number of inflammatory cells infiltrated in the bronchial and perivascular, pulmonary interstitial and alveolar spaces, and the bronchial wall and smooth muscles were thickened obviously in the asthma group. Rats in the Roxithromycin group showed milder inflammation and airway remodeling change than the asthma group. There was no obvious pathological damage in the control group. The concentration of IL-6 and IL-17 in BALF and serum of rats in the asthma group were significantly higher than those in the control group (P<0.01), and Roxithromycin inhibited the high expression of these cytokines (P<0.05). The expression of S100A8 and RAGE in the asthma group were significantly higher than those in the control group [(20.6±4.4) vs (7.1±2.0) ng/L; (885±118) vs (462±102) ng/L; (14.2±1.7) vs (7.6±1.8) ng/L; (774±166) vs (406±69) ng/L, all P<0.05], and Roxithromycin inhibited the high expression of these proteins [(14.3±3.7) vs (20.6±4.4) ng/L; (650±53) vs (885±118) ng/L; (10.4±1.2) vs (14.2±1.7) ng/L; (560±64) vs (728±72) ng/L] (all P<0.05). Meanwhile, the expression of Caveolin-1 in the asthma group was significantly lower than that in the control group (P<0.01), and Roxithromycin up-regulated its expression (P<0.01). Correlation analysis showed that there was a significantly positive correlation between the expression of S100A8 and RAGE (r=0.706, P<0.01), while there was a significantly negative correlation between the expression of S100A8 and Caveolin-1 (r=-0.775, P<0.01), and between the expression of Caveolin-1 and RAGE (r=-0.919, P<0.01). Conclusion: S100A8 and Caveolin-1 may play an important role in neutrophilic asthma via RAGE, and Roxithromycin may exerts anti-inflammatory effects and inhibition of airway remodeling partly through this signaling pathway.

[Expression of RAGE in asthmatic rats and the intervention of Roxithromycin]

Objective: To observe the expression of the Receptor of Advanced glycation end products (RAGE) in asthmatic rats, and explore the intervention of Roxithromycin. Methods: A total of 18 Specific Pathogen Free-class Brown Norway male rats were randomly divided into control group, asthma model group and Roxithromycin group, with 6 rats in each group. The asthmatic model was sensitized by intraperitoneal injection of Ovalbumin (OVA)+Al(OH)(3), and challenged with OVA. Rats in Roxithromycin group were given Roxithromycin 30 mg/kg 30 minutes before each challenge. Rats in control group and asthma model group were treated with equal volume of saline. The concentrations of RAGE and interleukin (IL)-4 in serum and bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent (ELISA); the pathological changes of lung tissues were observed by HE-staining; the thickness of airway wall and airway smooth muscle were measured by Image-Pro Plus; the relative expression of RAGE in lung tissues were detected by Western blot. Results: In asthma model group, the concentrations of RAGE and IL-4 in the serum and BALF were obviously higher than those in control group [(494±32) vs (327±45) ng/L; (32.4±5.8) vs (13.1±2.9) ng/L; (553±38) vs (399±56) ng/L; (37.8±3.4) vs (19.4±2.5) ng/L] (all P<0.01); in Roxithromycin group, the concentrations of RAGE and IL-4 in the serum and BALF were obviously lower than those in asthma model group [(438±18) vs (494±32) ng/L; (22.8±6.0) vs (32.4±5.8) ng/L; (444±42) vs (553±38) ng/L; (25.6±4.5) vs (37.8±3.4) ng/L] (all P<0.05). In asthma model group, the bronchial wall was thickened, the lumen was narrow, the mucosal wrinkles were significantly increased, edema appeared under the mucosa, and a large number of inflammatory cells infiltrated and aggregated in the bronchi, perivascular and alveolar spaces; the thickness of airway wall and airway smooth muscle were significantly increased than those in control group (P<0.01); in Roxithromycin group, airway inflammation and remodeling were alleviated compared with those in asthma model group (P<0.05). In asthma model group, the expression of RAGE in lung tissues were significantly increased than those in control group (P<0.01); in Roxithromycin group, the expression of RAGE were significantly decreased than those in asthma model group (P<0.01). There were positive correlations between the expression of RAGE and IL-4 in BALF and serum (r=0.782, 0.804, all P<0.01); there were positive correlations between RAGE and total white cell counts, eosinophil counts, smooth muscle thickness (r=0.897, 0.927, 0.860, all P<0.01). Conclusions: The increasing of RAGE in asthmatic rats are positively correlated with airway inflammation and airway remodeling. Roxithromycin may inhibit the development of asthma by reducing the expression of RAGE.

Author Correction: A recellularized human colon model identifies cancer driver genes

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

[Effects of human mesenchymal stem cells on airway inflammation in allergic asthma mice and the underlying mechanism]

Objectives: To investigate the effects of human umbilical cord mesenchymal stem cells (hUC-MSCs) on airway inflammation in an ovalbumin (OVA) induced asthma mouse model and the underlying mechanism. Methods: Twenty-four BALB/c mice were randomly divided into four equal groups: normal control group, OVA-induced asthmatic model group, hUC-MSCs treated group (50 μl of hUC-MSCs was transplanted into the trachea of asthmatic mice ) and hUC-MSCs control group (50 μl of hUC-MSCs was transplanted into the trachea of control mice). Human umbilical cord mesenchymal stem cells from umbilical cord of healthy new born babies were used as the source of hUC-MSCs for this study. The asthmatic conditions of the airways and the lungs were assessed by examining: (1) histopathological changes of the airways and the lungs; (2) expression of cytokines IL-6 and TGF-β mRNA by real-time PCR; (3) total leukocytes and mast cell count in bronchoalveolar lavage fluid (BALF) and number of IL-17-expressing CD4(+) cells (Th17 cells) in the lung tissue using flow cytometry. Results: Typical histopathological changes of asthma were confirmed in the asthmatic model group. These changes included intensive inflammatory cell infiltration around the airways and patchy airway occlusion by hyperviscous mucus. The number of total leukocytes and mast cells in BALF were significantly increased in the asthmatic mice when compared with the control group (P<0.05). Mice in the asthmatic model group had significantly higher percentage of Th17 cells in lung tissues when compared with the control group (2.90% vs 0.76%, P<0.05). In contrast, in the asthmatic mice treated with hUC-MSCs, the inflammatory cell infiltration was significantly reduced compared with asthmatic mice, as observed by significantly lower leukocytes and mast cells in BALF (P<0.05) and significant reduction in the percentage of Th17 cells in the lung of OVA-challenged mice following hUC-MSCs treatment (percentage of Th17 cells: 0.24% vs 2.90%, P<0.05). The expression of mRNA for IL-6 and TGF-β was significantly suppressed in the hUC-MSCs treatment group (0.23 vs 2.30 and 0.56 vs 6.60, both P<0.01). No asthmatic pathological changes in both normal and hUC-MSCs control groups were observed. Conclusions: hUC-MSCs significantly inhibit the airway inflammation in OVA-induced asthmatic mice. This inhibition is associated with the suppression of Th17 cells and the down-regulation of inflammatory factors such as IL-6 and TGF-β in the lungs.

Energy intake at different times of the day: Its association with elevated total and LDL cholesterol levels

BACKGROUND AND AIMS

This study examined the association between macronutrient intake at different times of the day and blood lipid levels.

METHODS AND RESULTS

The study was based on the Nutrition and Health Survey in Taiwan, a cross-sectional study of non-institutionalized and non-pregnant healthy adults (≥19-years-old). A one-day (24 h) dietary recall assessed participants' food intake. Fasting plasma triglycerides, total cholesterol, and high-density lipoprotein (HDL) cholesterol were determined. Low-density lipoprotein (LDL) cholesterol was estimated based on the Friedewald formula. According to the data of eligible subjects (n = 1283), the time of energy intake was categorized into three meal times 0500-0929 (morning), 1130-1329 (noon), and 1730-2029 (evening), along with three snack times 0930-1129 (mid-morning), 1330-1729 (afternoon), and 2030-0459 (night). Energy and macronutrient intake were calculated for the 6 time periods, based on 24 h recall data. An adjusted regression model showed that by transferring 100 kcal intake at night to the morning or noon, LDL cholesterol would be lower by 1.46 (95% CI: 2.42-0.50) and 1.27 mg/dL (95% CI: 2.24-0.30), respectively. Transferring 100 kcal of fat intake at night to earlier periods was associated with a lower LDL cholesterol level, especially transferring to noontime (significantly lower by 5.21 mg/dL, 95% CI: [7.42-2.99]) and evening (significantly lower by 3.19 mg/dL, 95% CI: [6.29-0.08]).

CONCLUSIONS

Total cholesterol and LDL cholesterol had the same pattern of association with the timing of energy intake. The study showed that elevated total and LDL cholesterol were positively associated with nighttime energy and fat intake.

[Comparison of three different posterior cervical approaches for treating cervical spine trauma with ossification of posterior longitudinal ligament]

Objective: To investigate the clinical application value of using laminoplasty combine with short-segment pedicle screw fixation in the treatment of cervical spine trauma patients with ossification of posterior longitudinal ligament (OPLL). Methods: Fifty-four cervical spine trauma patients with OPLL from June 2014 to June 2016 were retrospectively analyzed of Department of Spine Surgery, Changzheng Hospital, Naval Military Medical University. There were 31 males and 23 females, aging (68.4±4.3) years (rang: 46 to 82 years). All patients had a history of cervical spine trauma, confirmed by imaging examination of OPLL, and there are signs and symptoms related to cervical spinal cord compression. Eighteen patients underwent one-stage laminoplasty combine with short-segment pedicle screw fixation(group A), and 15 patients underwent posterior cervical laminectomy and pedicle screw fixation (group B). Twenty-one patients underwent posterior laminoplasty (C group). According to the range of OPLL and the compression of the spinal cord, the range of laminoplasty was selected. MRI scan was used to evaluated the compression condition of cervical spine and the injury condition of anterior longitudinal ligament injury and other factors that can cause local instability of the cervical spine. Posterior unilateral pedicle screw fixation (two pedicles) were performed in the instability segment. The neurological function of the patients was assessed by the Japanese Orthopedic Association (JOA) Score before surgery, the second day after surgery, 3 months, 1 year and the last follow-up. The cervical spine X-ray films were used to evaluate cervical curvature, cervical spine activity and internal fixation-related complications. Results: The average follow-up time was 18 months (6-30 months). Satisfactory neurological improvement was achieved in all three groups, and no internal fixation-related complications occurred during follow-up. The range of laminoplasty was 22 cases in 4 segments (C(3)-C(6), C(4)-C(7)) and 17 cases in 5 segments (C(3)-C(7)). Unilateral pedicle screw fixation was performed in 11 patients with C(3-4) fixation and 7 patients with C(4-5) fixation. Cervical curvature was basically the same in the three groups after operation and at the last follow-up. No significant changes in cervical curvature and kyphosis were observed during the follow-up period. The overall cervical mobility (C(2)-C(7)) in group A and group C had no significant difference compared with preoperative (P=0.077). The overall mobility of cervical vertebrae in group B was significantly lower than that before surgery (P=0.013). Conclusions: For cervical spine trauma patients with OPLL, laminoplasty combined short-segment pedicle screw fixation can increase cervical segmental stability while extensive decompression of cervical spinal cord compression. At the same time, to some extent, the complications of postoperative axial symptoms caused by posterior cervical laminectomy and pedicle screw fixation were avoided.

Generation of pulmonary neuroendocrine cells and SCLC-like tumors from human embryonic stem cells

By blocking an important signaling pathway (called NOTCH) and interfering with expression of two tumor suppressor genes in cells derived from human embryonic stem cells, Chen et al. have developed a model for studying small cell lung cancers.

Cancer models based on cells derived from human embryonic stem cells (hESCs) may reveal why certain constellations of genetic changes drive carcinogenesis in specialized lineages. Here we demonstrate that inhibition of NOTCH signaling induces up to 10% of lung progenitor cells to form pulmonary neuroendocrine cells (PNECs), putative precursors to small cell lung cancers (SCLCs), and we can increase PNECs by reducing levels of retinoblastoma (RB) proteins with inhibitory RNA. Reducing levels of TP53 protein or expressing mutant KRAS or EGFR genes did not induce or expand PNECs, but tumors resembling early-stage SCLC grew in immunodeficient mice after subcutaneous injection of PNEC-containing cultures in which expression of both RB and TP53 was blocked. Single-cell RNA profiles of PNECs are heterogeneous; when RB levels are reduced, the profiles resemble those from early-stage SCLC; and when both RB and TP53 levels are reduced, the transcriptome is enriched with cell cycle–specific RNAs. Our findings suggest that genetic manipulation of hESC-derived pulmonary cells will enable studies of this recalcitrant cancer.

Engineering a Bioartificial Human Colon Model Through Decellularization and Recellularization

The tissue engineering method of decellularization and recellularization has been successfully used in a variety of regenerative medicine applications. The protocols used to de/recellularize various organs and tissues are largely different. Here we describe a method to effectively engineer a bioartificial colon by completely removing original cells from human intestinal tissues followed by repopulating the acellular tissue matrix with cell cultures. This method provides a novel approach for human intestinal regeneration and can be used to identify potential cancer driver genes.

IGFBP2 promotes vasculogenic mimicry formation via regulating CD144 and MMP2 expression in glioma

Vasculogenic mimicry (VM) refers to the fluid-conducting channels formed by aggressive tumor cells rather than endothelial cells (EC) with elevated expression of genes associated with vascularization. VM has been considered as one of the reasons that glioblastoma becomes resistant to anti-VEGF therapy. However, the molecular basis underlying VM formation remains unclear. Here we report that the insulin-like growth factor-binding protein 2 (IGFBP2) acts as a potent factor to enhance VM formation in glioma. Evidence showed that elevated IGFBP2 expression was positively related with VM formation in patients with glioma. Enforced expression of IGFBP2 increased network formation of glioma cells in vitro by activating CD144 and MMP2 (Matrix Metalloproteinase 2). U251 cells with stable knockdown of IGFBP2 led to decreased VM formation and tumor progression in orthotopic mouse model. Mechanistically, IGFBP2 interacts with integrin α5 and β1 subunits and augments CD144 expression in a FAK/ERK pathway-dependent manner. Luciferase reporter and ChIP assay suggested that IGFBP2 activated the transcription factor SP1, which could bind to CD144 promoter. Thus, IGFBP2 acts as a stimulator of VM formation in glioma cells via enhancing CD144 and MMP2 expression.

A pumpless body-on-a-chip model using a primary culture of human intestinal cells and a 3D culture of liver cells

We describe an expanded modular gastrointestinal (GI) tract-liver system by co-culture of primary human intestinal epithelial cells (hIECs) and 3D liver mimic. The two organ body-on-chip design consisted of GI and liver tissue compartments that were connected by fluidic medium flow driven via gravity. The hIECs and HepG2 C3A liver cells in the co-culture system maintained high viability for at least 14 days in which hIECs differentiated into major cell types found in native human intestinal epithelium and the HepG2 C3A cells cultured on 3D polymer scaffold formed a liver micro-lobe like structure. Moreover, the hIECs formed a monolayer on polycarbonate membranes with a tight junction and authentic TEER values of approximately 250 Ω cm2 for the native gut. The hIEC permeability was compared to a conventional permeability model using Caco-2 cell response for drug absorption by measuring the uptake of propranolol, mannitol and caffeine. Metabolic rates (urea or albumin production) of the cells in the co-culture GI-liver system were comparable to those of HepG2 C3A cells in a single-organ fluidic culture system, while induced CYP activities were significantly increased in the co-culture GI tract-liver system compared to the single-organ fluidic culture system. These results demonstrated potential of the low-cost microphysiological GI-liver model for preclinical studies to predict human response.

[Advances in the research of application of three-dimensional bioprinting in skin tissue engineering]

Deep skin wounds require skin grafts for coverage. Current treatments such as tissue engineered skin or skin substitutes can not meet the needs of clinical application due to the technical problems involving preservation, transportation, and a lengthy preparation process. In comparison with traditional methods such as freeze-drying, three-dimensional bioprinting can precisely dispense living cells, nucleic acid, growth factor, and phase-changing hydrogels according to the wound form, while maintaining high cell viability. Besides, it has excellent performance in high resolution, flexibility, reproducibility, and high throughput, showing great potential in the fabrication of tissue engineered skin. This review mainly introduces the common techniques of three-dimensional bioprinting, and their application in skin tissue engineering, focusing on the latest research progress, and summarizes the current challenges and future development of three-dimensional skin printing.

Corrigendum: Colonic organoids derived from human induced pluripotent stem cells for modeling colorectal cancer and drug testing

This corrects the article DOI: 10.1038/nm.4355.

Severe hypoglycemia and hip fracture in patients with type 2 diabetes: a nationwide population-based cohort study

Hypoglycemia is a major concern in glycemic control. Using the Taiwan National Health Insurance Research Database, we found that the risk of hip fracture was associated with emergency or hospitalization visits of severe hypoglycemia in patients with type 2 diabetes; greater visits were associated with higher incidence of hip fracture.

INTRODUCTION

The objective of the study was to assess the risk of hip fracture among patients with type 2 diabetes mellitus (T2DM) and severe hypoglycemia.

METHODS

Using the National Health Insurance Research database in Taiwan, we identified 2588 patients with T2DM who had developed severe hypoglycemia from 2001 to 2009. A comparison cohort who had never developed severe hypoglycemia was frequency matched at a ratio of approximately 1:2. Multivariate Cox proportional hazard regression analysis was used to evaluate the risk of hip fracture.

RESULTS

During a median follow-up period of 3.9 years, there were 219 hip fracture events in 5173 comparison cohorts and 148 hip fracture events in 2588 hypoglycemia cohorts. The incidence of hip fracture was higher in patients with severe hypoglycemia than without severe hypoglycemia (17.19 vs. 8.83 per 1000 person-years; adjusted HR 1.71, 95% CI = 1.35-2.16). Approximately half of the individuals developed hip fracture within 2 years from the first occurrence of severe hypoglycemia. There was a significant associated trend towards increased hip fracture risk with increasing average visit of severe hypoglycemia per year (p for trend <0.001). Medication analysis showed that patients taking sulfonylurea alone, insulin alone, and insulin secretagogues combined with insulin had a higher associated risk to develop hip fracture.

CONCLUSIONS

Severe hypoglycemia was associated with a higher risk to develop hip fracture. The more the visits of severe hypoglycemia per year indicated the higher associated risk in patients with T2DM. Fall is likely an important reason for severe hypoglycemia in relation to increased risk of hip fracture.

Colonic organoids derived from human induced pluripotent stem cells for modeling colorectal cancer and drug testing

With the goal of modeling human disease of the large intestine, we sought to develop an effective protocol for deriving colonic organoids (COs) from differentiated human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs). Extensive gene and immunohistochemical profiling confirmed that the derived COs represent colon rather than small intestine, containing stem cells, transit-amplifying cells, and the expected spectrum of differentiated cells, including goblet and endocrine cells. We applied this strategy to iPSCs derived from patients with familial adenomatous polyposis (FAP-iPSCs) harboring germline mutations in the WNT-signaling-pathway-regulator gene encoding APC, and we generated COs that exhibit enhanced WNT activity and increased epithelial cell proliferation, which we used as a platform for drug testing. Two potential compounds, XAV939 and rapamycin, decreased proliferation in FAP-COs, but also affected cell proliferation in wild-type COs, which thus limits their therapeutic application. By contrast, we found that geneticin, a ribosome-binding antibiotic with translational 'read-through' activity, efficiently targeted abnormal WNT activity and restored normal proliferation specifically in APC-mutant FAP-COs. These studies provide an efficient strategy for deriving human COs, which can be used in disease modeling and drug discovery for colorectal disease.