[Dynamic observation on capillarization of liver sinusoidal endothelial cells induced by Echinococcus multilocularis infection]

OBJECTIVE

To investigate the capillarization of liver sinusoidal endothelial cells (LSECs) and its association with hepatic fibrosis during the development of alveolar echinococcosis, so as to provide the basis for unraveling the mechanisms underlying the role of LSEC in the development and prognosis of hepatic injuries and hepatic fibrosis caused by alveolar echinococcosis.

METHODS

Forty C57BL/6 mice at ages of 6 to 8 weeks were randomly divided into a control group and 1-, 2- and 4-week infection groups, of 10 mice in each group. Each mouse in the infection groups was intraperitoneally injected with 2 000 Echinococcus multilocularis protoscoleces, while each mouse in the control group was given an equal volume of phosphate-buffered saline using the same method. All mice were sacrificed 1, 2 and 4 weeks post-infection and mouse livers were collected. The pathological changes of livers were observed using hematoxylin-eosin (HE) staining, and hepatic fibrosis was evaluated through semi-quantitative analysis of Masson's trichrome staining-positive areas. The activation of hepatic stellate cells (HSCs) and extracellular matrix (ECM) deposition were examined using immunohistochemical staining of α-smooth muscle actin (α-SMA) and collagen type I alpha 1 (COL1A1), and the fenestrations on the surface of LSECs were observed using scanning electron microscopy. Primary LSECs were isolated from mouse livers, and the mRNA expression of LSEC marker genes Stabilin-1, Stabilin-2, Ehd3, CD209b, GATA4 and Maf was quantified using real-time fluorescence quantitative PCR (qPCR) assay.

RESULTS

Destruction of local liver lobular structure was observed in mice 2 weeks post-infection with E. multilocularis protoscoleces, and hydatid cysts, which were surrounded by granulomatous tissues, were found in mouse livers 4 weeks post-infection. Semi-quantitative analysis of Masson's trichrome staining showed a significant difference in the proportion of collagen fiber contents in mouse livers among the four groups (F = 26.060, P < 0.001), and a higher proportion of collagen fiber contents was detected in mouse livers in the 4-week infection group [(11.29 ± 2.58)%] than in the control group (P < 0.001). Immunohistochemical staining revealed activation of a few HSCs and ECM deposition in mouse livers 1 and 2 weeks post-infection, and abundant brown-yellow stained α-SMA and COL1A1 were deposited in the lesion areas in mouse livers 4 weeks post-infection, which spread to surrounding tissues. Semi-quantitative analysis revealed significant differences in α-SMA (F = 7.667, P < 0.05) and COL1A1 expression (F = 6.530, P < 0.05) in mouse levers among the four groups, with higher α-SMA [(7.13 ± 3.68)%] and COL1A1 expression [(13.18 ± 7.20)%] quantified in mouse livers in the 4-week infection group than in the control group (both P values < 0.05). Scanning electron microscopy revealed significant differences in the fenestration frequency (F = 37.730, P < 0.001) and porosity (F = 16.010, P < 0.001) on the surface of mouse LSECs among the four groups, and reduced fenestration frequency and porosity were observed in the 1-[(1.22 ± 0.48)/μm2 and [(3.05 ± 0.91)%] and 2-week infection groups [(3.47 ± 0.10)/μm2 and (7.57 ± 0.23)%] groups than in the control group (all P values < 0.001). There was a significant difference in the average fenestration diameter on the surface of mouse LSECs among the four groups (F = 15.330, P < 0.001), and larger average fenestration diameters were measured in the 1-[(180.80 ± 16.42) nm] and 2-week infection groups [(161.70 ± 3.85) nm] than in the control group (both P values < 0.05). In addition, there were significant differences among the four groups in terms of Stabilin-1 (F = 153.100, P < 0.001), Stabilin-2 (F = 57.010, P < 0.001), Ehd3 (F = 31.700, P < 0.001), CD209b (F = 177.400, P < 0.001), GATA4 (F = 17.740, P < 0.001), and Maf mRNA expression (F = 72.710, P < 0.001), and reduced mRNA expression of Stabilin-1, Stabilin-2, Ehd3, CD209b, GATA4 and Maf genes was quantified in three infection groups than in the control group (all P values < 0.001).

CONCLUSIONS

E. multilocularis infections may induce capillarization of LSECs in mice, and result in a reduction in the expression of functional and phenotypic marker genes of LSECs, and capillarization of LSECs occurs earlier than activation of HSC and development of hepatic fibrosis.

Colorectal cancer cells secreting DKK4 transform fibroblasts to promote tumour metastasis

Wnt/β-catenin signalling is aberrantly activated in most colorectal cancer (CRC) and is one key driver involved in the initiation and progression of CRC. However, mutations of APC gene in CRC patients retain certain activity of APC protein with decreased β-catenin signalling and DKK4 expression significantly upregulates and represses Wnt/β-catenin signalling in human CRC tissues, suggesting that a precisely modulated activation of the Wnt/β-catenin pathway is essential for CRC formation and progression. The underlying reasons why a specifically reduced degree, not a fully activating degree, of β-catenin signalling in CRC are unclear. Here, we showed that a soluble extracellular inhibitor of Wnt/β-catenin signalling, DKK4, is an independent factor for poor outcomes in CRC patients. DKK4 secreted from CRC cells inactivates β-catenin in fibroblasts to induce the formation of stress fibre-containing fibroblasts and myofibroblasts in culture conditions and in mouse CRC xenograft tissues, resulting in restricted expansion in tumour masses at primary sites and enhanced CRC metastasis in mouse models. Reduced β-catenin activity by a chemical inhibitor MSAB promoted the CRC metastasis. Our findings demonstrate why reduced β-catenin activity is needed for CRC progression and provide a mechanism by which interactions between CRC cells and stromal cells affect disease promotion.

Genetic insights into across pancreatitis types: the causal influence of immunoglobulin G N-glycosylation variants on disease risk

Background

While a few case-control studies indicated a possible correlation of IgG N-glycosylation patterns with pancreatitis, their restricted sample sizes and methodologies prevented conclusive insights into causality or distinguishing traits across pancreatitis types.

Method

We conducted a two-sample Mendelian Randomization (MR) analysis to investigate the causal relationship between 77 IgG N-glycosylation traits and various types of pancreatitis, including acute pancreatitis (AP), chronic pancreatitis (CP), alcohol acute pancreatitis (AAP), and alcohol chronic pancreatitis (ACP). This analysis utilized summary-level data from genome-wide association studies (GWAS), employing methods such as IVW, MR-Egger, and weighted median. To ensure the robustness of our findings, several sensitivity analyses, including Cochran's Q statistic, leave-one-out, MR-Egger intercept, and MR-PRESSO global test were conducted.

Result

Our study uncovered the causal relationship between specific IgG N-glycosylation traits and various types of pancreatitis. Notably, an increase in genetically predicted IGP7 levels was associated with a decreased risk of developing AP. For CP, our data suggested a protective effect associated with higher levels of both IGP7 and IGP31, contrasting with increased levels of IGP27 and IGP65, which were linked to a heightened risk. Moreover, in the case of AAP, elevated IGP31 levels were causatively associated with a lower incidence, while higher IGP26 levels correlated with an increased risk for ACP.

Conclusion

This study establishes causal relationship between specific IgG N-glycosylation patterns and varying risks of different pancreatitis forms, underscoring their potential as predictive biomarkers. These findings necessitate further exploration into the underlying mechanisms, promising to inform more personalized diagnostic and therapeutic strategies in pancreatitis management.

Hepatitis B virus infection disrupts homologous recombination in hepatocellular carcinoma by stabilizing resection inhibitor ADRM1

Many cancers harbor homologous recombination defects (HRDs). A HRD is a therapeutic target that is being successfully utilized in treatment of breast/ovarian cancer via synthetic lethality. However, canonical HRD caused by BRCAness mutations do not prevail in liver cancer. Here we report a subtype of HRD caused by the perturbation of a proteasome variant (CDW19S) in hepatitis B virus-bearing (HBV-bearing) cells. This amalgamate protein complex contained the 19S proteasome decorated with CRL4WDR70 ubiquitin ligase, and assembled at broken chromatin in a PSMD4Rpn10- and ATM-MDC1-RNF8-dependent manner. CDW19S promoted DNA end processing via segregated modules that promote nuclease activities of MRE11 and EXO1. Contrarily, a proteasomal component, ADRM1Rpn13, inhibited resection and was removed by CRL4WDR70-catalyzed ubiquitination upon commitment of extensive resection. HBx interfered with ADRM1Rpn13 degradation, leading to the imposition of ADRM1Rpn13-dependent resection barrier and consequent viral HRD subtype distinguishable from that caused by BRCA1 defect. Finally, we demonstrated that viral HRD in HBV-associated hepatocellular carcinoma can be exploited to restrict tumor progression. Our work clarifies the underlying mechanism of a virus-induced HRD subtype.

Chloroquine Alleviates Atherosclerosis by Modulating Regulatory T Cells Through the ATM/AMPK/mTOR Signaling Pathway in ApoE -/- Mice

BACKGROUND

Clinical observation suggests the atheroprotective effect of chloroquine and its derivatives, while its mechanism remains unclear. This study aimed to observe the protective effect of chloroquine against atherosclerosis and explore the underlying mechanism.

METHODS

Ataxia telangiectasia mutated (ATM) wild-type or haploinsufficient apolipoprotein-E-knockout (ATM+/+ApoE-/- or ATM+/-ApoE-/-) mice were treated with different dosages of chloroquine. Anti-CD25 antibody was used to deplete natural Tregs in ATM+/+ApoE-/- mice. The atherosclerotic burden in different groups of mice was comprehensively evaluated by H&E staining and Masson staining. The effect of chloroquine on the regulatory T cells (Tregs) was assessed in vivo and in vitro by flow cytometry and immunohistochemical staining. The expression of related proteins was detected by real-time polymerase chain reaction and western blotting.

RESULTS

In ATM+/+ApoE-/- mice, chloroquine alleviated atherosclerotic lesions, stabilized the plaque, and increased Treg counts in the atherosclerotic lesions and spleens. However, in ATM haploinsufficient mice (ATM+/-ApoE-/-), chloroquine no longer prevented atherosclerosis or impacted Treg counts. Abolishing Treg cells using an anti-CD25 antibody in vivo abrogated the atheroprotective effect of chloroquine. In vitro, chloroquine promoted the differentiation of Tregs from naïve T cells, which was accompanied by enhanced ATM/AMP-activated protein kinase (AMPK) activity and reduced downstream mammalian target of rapamycin (mTOR) activity.

DISCUSSION

These findings suggest that chloroquine ameliorates atherosclerosis and stabilizes plaque by modulating Tregs differentiation through the regulation of the ATM/AMPK/mTOR pathway.

Live-Cell Imaging of Endogenous RNA with a Genetically Encoded Fluorogenic Allosteric Aptamer

Imaging and tracking tools for natural cellular RNA with improved biocompatibility, specificity, and sensitivity are critical to understanding RNA function and providing insights into disease therapeutics. We developed a new genetically encoded sensor using fluorogenic allosteric aptamer (FaApt) for the sensitive imaging of the localization and dynamics of RNA targets in live cells. Target RNAs can be specifically recognized with our sensor by forming perfectly complementary duplexes, which in turn can induce allosteric structural changes of the sensor to refold the native conformation of fluorogenic RNA aptamers. We demonstrated the ability of the sensor to monitor the effect of tumor necrosis factor and small-molecule inhibitor on the expression abundance of CXCL1 and survivin mRNA in human cancer cells, respectively. The asymmetrical distribution of endogenous Squint mRNA was confirmed in developing zebrafish embryos through microinjection of FaApt probes. This study provides an effective molecular tool for sensitive imaging and tracking endogenous RNA in living cells. Due to the high specificity and small size of our sensor system, it is expected to be applied to early diagnosis of RNA marker-related diseases and real-time evaluation of the treatment process.

Incorporation of a Toll-like receptor 2/6 agonist potentiates mRNA vaccines against cancer and infectious diseases

mRNA vaccines have emerged rapidly in recent years as a prophylactic and therapeutic agent against various diseases including cancer and infectious diseases. Improvements of mRNA vaccines have been underway, among which boosting of efficacy is of great importance. Pam2Cys, a simple synthetic metabolizable lipoamino acid that signals through Toll-like receptor (TLR) 2/6 pathway, eliciting both humoral and cellular adaptive immune responses, is an interesting candidate adjuvant. To investigate the enhancement of the efficacies of mRNA vaccines by Pam2Cys, the adjuvant was incorporated into mRNA-lipid nanoparticles (LNPs) to achieve co-delivery with mRNA. Immunization with the resulting mRNA-LNPs (Pam2Cys) shaped up the immune milieu in the draining lymph nodes (dLNs) through the induction of IL-12 and IL-17, among other cytokines. Antigen presentation was carried out mainly by migratory and dLN-resident conventional type 2 DCs (cDC2s) and significantly more potent antitumor responses were triggered in both prophylactic and therapeutic tumor models in a CD4⁺ and CD8⁺ T cell-dependent fashion. Accompanying memory antitumor immunity was also established. Moreover, the vaccine also stimulated much more robust humoral and cellular immunity in a surrogate COVID-19 prophylactic model. Last but not the least, the new vaccines exhibited good preliminary safety profiles in murine models. These facts warrant future development of Pam2Cys-incorporated mRNA vaccines or relevant mRNA therapeutics for clinical application.

Gene expression networks involved in multiple cellular programs coexist in individual hepatocellular cancer cells

The gene expression networks of a single cell can be used to reveal cell type- and condition-specific patterns that account for cell states, cell identity, and its responses to environmental changes. We applied single cell sequencing datasets to define mRNA patterns and visualized potential cellular capacities among hepatocellular cancer cells. The expressing numbers and levels of genes were highly heterogenous among the cancer cells. The cellular characteristics were dependent strongly on the expressing numbers and levels of genes, especially oncogenes and anti-oncogenes, in an individual cancer cell. The transcriptional activations of oncogenes and anti-oncogenes were strongly linked to inherent multiple cellular programs, some of which oppose and contend against other processes, in a cancer cell. The gene expression networks of multiple cellular programs proliferation, differentiation, apoptosis, autophagy, epithelial-mesenchymal transition, ATP production, and neurogenesis coexisted in an individual cancer cell. The findings give rise a hypothesis that a cancer cell expresses balanced combinations of genes and undergoes a given biological process by rapidly transmuting gene expressing networks.

Defective neurite elongation and branching in Nibp/Trappc9 deficient zebrafish and mice

Loss of function in transport protein particles (TRAPP) links a new set of emerging genetic disorders called "TRAPPopathies". One such disorder is NIBP syndrome, characterized by microcephaly and intellectual disability, and caused by mutations of NIBP/TRAPPC9, a crucial and unique member of TRAPPII. To investigate the neural cellular/molecular mechanisms underlying microcephaly, we developed Nibp/Trappc9-deficient animal models using different techniques, including morpholino knockdown and CRISPR/Cas mutation in zebrafish and Cre/LoxP-mediated gene targeting in mice. Nibp/Trappc9 deficiency impaired the stability of the TRAPPII complex at actin filaments and microtubules of neurites and growth cones. This deficiency also impaired elongation and branching of neuronal dendrites and axons, without significant effects on neurite initiation or neural cell number/types in embryonic and adult brains. The positive correlation of TRAPPII stability and neurite elongation/branching suggests a potential role for TRAPPII in regulating neurite morphology. These results provide novel genetic/molecular evidence to define patients with a type of non-syndromic autosomal recessive intellectual disability and highlight the importance of developing therapeutic approaches targeting the TRAPPII complex to cure TRAPPopathies.

Dopey2 and Pcdh7 orchestrate the development of embryonic neural stem cells/ progenitors in zebrafish

DOPEY2 has been shown to be associated with Down syndrome and PCDH7 might be involved in Rett syndrome and MECP2 duplication syndrome. The mechanism how both proteins play roles in these syndromes are largely unknown. Here, we show that Dopey2 and Pcdh7 balance the proliferation and differentiation of neural stem cells and progenitors during embryonic neurogenesis to generate proper size and architecture of zebrafish brains. Dopey2 and Pcdh7 mutually restricted expression of each other in zebrafish embryos. Dopey2 was responsible for the proliferation of neural stem cells/progenitors, whereas Pcdh7 was responsible for the differentiation of neural stem cells/progenitors. Both proteins were shown to orchestrate the proper development and arrangement of neural cells in zebrafish embryonic brains. The results provide an insight into mechanisms to understand how the embryonic brain is constituted and how developmental defects occur in the brains of patients with Down syndrome, Rett syndrome, or MECP2 duplication syndrome.

An integrated map of fibroblastic populations in human colon mucosa and cancer tissues

Fibroblasts and myofibroblasts are major mesenchymal cells in the lamina propria of colon mucosa and in colon cancer tissues. Detailed insight into the highly specific populations of fibroblasts and myofibroblasts is required to understand the integrity and homeostasis of human colon mucosa and colon cancer. Based on gene expression profiles of single cells, we identified fibroblast populations that produce extracellular matrix components, Wnt ligand- and BMP-secreting fibroblasts, chemokine- and chemokine ligand-generating fibroblasts, highly activated fibroblasts, immune-modulating fibroblasts, epithelial cell-modulating myofibroblasts, stimuli-responsive myofibroblasts, proliferating myofibroblasts, fibroblast-like myofibroblasts, matrix producing myofibroblasts, and contractile myofibroblasts in human colon mucosa. In colon cancer tissue, the compositions of fibroblasts and myofibroblasts were highly altered, as were the expressing patterns of genes including BMPs, Wnt ligands, chemokines, chemokine ligands, growth factors and extracellular matrix components in fibroblasts and myofibroblasts. Our work expands the working atlas of fibroblasts and myofibroblasts and provides a framework for interrogating the complexity of stromal cells in human healthy colon mucosa and colon cancer tissues.

Abstract 5569: CAR-T cells with αPDL1/CD28 switch-receptor synergize radiotherapy and anti-PD1 therapy in solid tumors

The therapeutic efficacy of CAR-T cells in solid tumors, unlike in hematologic tumor, is greatly limited by the insufficient infiltration and persistence of CAR-T cells as well as the immunosuppressive tumor microenvironment. The aim of this study was to overcome these obstacles by introducing an αPDL1/CD28 switch-receptor construct and by seeking combinatorial strategies for CAR-T cells in solid tumors. We found that in non-transduction T cells, the cytokine release and T cell proliferation were repressed in response to PD-L1 protein, while T cells that express αPDL1/CD28 switch-receptor showed enhanced functions, indicating that αPDL1/CD28 could revert PD-L1 inhibition into CD28 costimulation. CAR-T cells with αPDL1/CD28 switch-receptor showed better effector function than that of unitary CAR-T in vitro studies and significant responses in tumor-bearing mice, with more effector memory T cells infiltrated in the tumor. On this basis, PD-1 inhibitor can further enhance the efficacy and persistence of αPDL1/CD28 CAR-T cells, especially in PDL1+ tumor models. We found in vitro studies that radiotherapy increased the expression of T-cell recruiting chemokines and promoted CAR-T cell transmigration. In tumor-bearing mice, synergistic anti-tumor efficacy of mice treated with radiotherapy and αPDL1/CD28 CAR-T cells was further observed. Finally, triple therapy with radiotherapy and anti-PD1 plus αPDL1/CD28 CAR-T cells maximized antitumor responses and induced complete cures in the tumor-bearing mice. Our study suggests that αPDL1/CD28 augments the function of CAR-T cells, and the combinatorial regime of αPDL1/CD28 CAR-T cells, radiotherapy and anti-PD1 in solid tumors could be further investigated.

Citation Format: Limei Yin, Wenbo Wang, Zhuoran Yao, Jianxin Xue, Ruizhan Tong, Hui Wang, Shuangsi Liao, Laduona Wang, Yue Zheng, Feifei Na, Min Yu, Xuanwei Zhang, Youling Gong, Meijuan Huang, Xianming Mo, Chong Chen, You Lu. CAR-T cells with αPDL1/CD28 switch-receptor synergize radiotherapy and anti-PD1 therapy in solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5569.

SM22α-lineage niche cells regulate intramembranous bone regeneration via PDGFRβ-triggered hydrogen sulfide production

Bone stromal cells are critical for bone homeostasis and regeneration. Growing evidence suggests that non-stem bone niche cells support bone homeostasis and regeneration via paracrine mechanisms, which remain to be elucidated. Here, we show that physiologically quiescent SM22α-lineage stromal cells expand after bone injury to regulate diverse processes of intramembranous bone regeneration. The majority of SM22α-lineage cells neither act as stem cells in vivo nor show their expression patterns. Dysfunction of SM22α-lineage niche cells induced by loss of platelet-derived growth factor receptor β (PDGFRβ) impairs bone repair. We further show that PDGFRβ-triggered hydrogen sulfide (H₂S) generation in SM22α-lineage niche cells facilitates osteogenesis and angiogenesis and suppresses overactive osteoclastogenesis. Collectively, these data demonstrate that non-stem SM22α-lineage niche cells support the niche for bone regeneration with a PDGFRβ/H₂S-dependent regulatory mechanism. Our findings provide further insight into non-stem bone stromal niche cell populations and niche-regulation strategy for bone repair.

Prognostic value and biological function of LRRN4 in colorectal cancer

Background

Several nervous and nerve-related biomarkers have been detected in colorectal cancer (CRC) and can contribute to the progression of CRC. However, the role of leucine-rich repeat neuronal 4 (LRRN4), a recently identified neurogenic marker, in CRC remains unclear.

Methods

We examined the expression and clinical outcomes of LRRN4 in CRC from TCGA-COREAD mRNA-sequencing datasets and immunohistochemistry in a Chinese cohort. Furthermore, colony formation, flow cytometry, wound healing assays and mouse xenograft models were used to investigate the biological significance of LRRN4 in CRC cell lines with LRRN4 knockdown or overexpression in vitro and in vivo. In addition, weighted coexpression network analysis, DAVID and western blot analysis were used to explore the potential molecular mechanism.

Results

We provide the first evidence that LRRN4 expression, at both the mRNA and protein levels, was remarkably high in CRC compared to controls and positively correlated with the clinical outcome of CRC patients. Specifically, LRRN4 was an independent prognostic factor for progression-free survival and overall survival in CRC patients. Further functional experiments showed that LRRN4 promoted cell proliferation, cell DNA synthesis and cell migration and inhibited apoptosis. Knockdown of LRRN4 can correspondingly decrease these effects in vitro and can significantly suppress the growth of xenografts. Several biological functions and signaling pathways were regulated by LRRN4, including proteoglycans in cancer, glutamatergic synapse, Ras, MAPK and PI3K. LRRN4 knockdown resulted in downregulation of Akt, p-Akt, ERK1/2 and p-ERK1/2, the downstream of the Ras/MAPK signaling pathway, overexpression of LRRN4 leaded to the upregulation of these proteins.

Conclusions

Our results suggest that LRRN4 could be a biological and molecular determinant to stratify CRC patients into distinct risk categories, and mechanistically, this is likely attributable to LRRN4 regulating several malignant phenotypes of neoplastic cells via RAS/MAPK signal pathways.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02579-x.

A genetically encoded fluorescent biosensor for monitoring ATP in living cells with heterobifunctional aptamers

Visualizing the dynamics of ATP in living cells is key to understanding cellular energy metabolism and related diseases. However, the live-cell applications of current methods are still limited due to challenges in biological compatibility and sensitivity to pH. Herein, a novel label-free fluorescent " turn-on " biosensor for monitoring ATP in living bacterias and mammalian cells was developed. This biosensor (Broc-ATP) employed heterobifunctional aptamers to detect ATP with high sensitivity in vitro. In our system, a very useful tandem method was established by combining four Broc-ATPs with 3 × F30 three-way junction scaffold to construct an intracellular biosensor that achieves sufficient fluorescence to respond to intracellular ATP. This intracellular biosensor can be used for sensitive and specific dynamic imaging of ATP in mammalian cells. Hence, this genetically encoded biosensor provides a robust and efficient tool for the detection of intracellular ATP dynamics and 3 × F30 tandem method expands the application of heterobifunctional aptamers in mammalian cells.

Three Novel Structural Variations at MHC and IL12B Predisposing to Psoriasis

BACKGROUND

Structural variations (SVs, defined as DNA variants ≥50 bp) have been associated with various complex human diseases. However, research to screen the whole genome for SVs predisposing to psoriasis is still lacking.

OBJECTIVES

This study aimed to investigate the association of SVs and psoriasis.

METHODS

We performed a genome-wide screen on SVs using an imputation method on 5 independent cohorts with 45,386 subjects from the Chinese Han population. Fine mapping analysis, genetic interaction analysis and RNA expression analysis were conducted to explore the mechanism of SVs.

RESULTS

We obtained 4,535 SVs in total and identified 2 novel deletions (esv3608550, OR=2.73, P<2.00×10^-308 ; esv3608542, OR=0.47, P=7.40×10^-28 ) at 6q21.33 (MHC), 1 novel Alu element insertion (esv3607339, OR=1.22, P=1.18×10^-35 ) at 5q33.3 (IL12B), and confirmed 1 previously reported deletion (esv3587563, OR=1.30, P=9.52×10^-60 ) at 1q21.2 (LCE) for psoriasis. Fine mapping analysis including SNPs and small Insertions/Deletions (InDels) revealed that esv3608550 and esv3608542 were independently associated with psoriasis, and a novel independent SNP (rs9378188, OR=1.65, P=3.46×10^-38 ) was identified at 6q21.33. By genetic interaction analysis and RNA expression analysis, we speculate that the association of 2 deletions at 6q21.33 with psoriasis might relate to their influence on the expression of HLA-C.

CONCLUSIONS

Our study constructed the most comprehensive SV map for psoriasis thus far and enriched the genetic architecture and pathogenesis of psoriasis as well as highlighted the nonnegligible impact of SVs on complex diseases.

Expression of lncRNA NEAT1 in peripheral blood mononuclear cells of patients with systemic lupus erythematosus and its correlation with Th1/Th2 balance

OBJECTIVE

This study explored and analyzed the expression of LncRNA NEAT1 in peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE) and its correlation with Th1/Th2 balance.

METHODS

We chose 97 SLE patients admitted in our hospital from Jun. 2016 to Feb. 2019 as SLE group, and randomly selected 50 healthy volunteers that underwent physical examination in our hospital during the same period as control group. We detected the expression of LncRNA NEAT1 in PBMCs of the two groups of subjects by qRT-PCR, the degree of Th1 and Th2 cells in both groups by flow cytometry, and the expression of TFN-γ and IL-4 in both groups by ELISA.

RESULTS

The relative expression of LncRNA NEAT1 in PBMCs of SLE group was higher than that of control group (P<0.05). The proportion of Th1 and the ratio of Th1/Th2 cells in PBMCs were markedly lower in the SLE group than the control group (P<0.05), while the proportion of Th2 was higher in the SLE group than the control group (P<0.05). IFN-γ level in SLE group was much lower than the control group (P<0.05), while IL-4 level was evidently higher in the SLE group than in controls (P<0.05). The expression of LncRNA NEAT1 in PBMCs of SLE group was notably negatively correlated with Th1 proportion and Th1/Th2 ratio (P<0.05), while positively correlated with Th2 proportion (P<0.05).

CONCLUSION

LncRNA NEAT1 in PBMCs of SLE patients is abnormally highly expressed, and this expression is negatively correlated with Th1/Th2 balance. These two factors may interact and jointly affect the occurrence and progression of SLE.

GMPPB-congenital disorders of glycosylation associate with decreased enzymatic activity of GMPPB

The congenital disorders of glycosylation (CDG) are a family of metabolic diseases in which glycosylation of proteins or lipids is deficient. GDP-mannose pyrophosphorylase B (GMPPB) mutations lead to CDG, characterized by neurological and muscular defects. However, the genotype-phenotype correlation remains elusive, limiting our understanding of the underlying mechanism and development of therapeutic strategy. Here, we report a case of an individual presenting congenital muscular dystrophy with cerebellar involvement, who presents two heterozygous GMPPB mutations (V111G and G214S). The V111G mutation significantly decreases GMPPB’s enzymatic activity. By measuring enzymatic activities of 17 reported GMPPB mutants identified in patients diagnosed with GMPPB-CDG, we discover that all tested GMPPB variants exhibit significantly decreased enzymatic activity. Using a zebrafish model, we find that Gmppb is required for neuronal and muscle development, and further demonstrate that enzymatic activity of GMPPB mutants correlates with muscular and neuronal phenotypes in zebrafish. Taken together, our findings discover the importance of GMPPB enzymatic activity for the pathogenesis of GMPPB-CDG, and shed light for the development of additional indicators and therapeutic strategy.

Imbalanced Innate Lymphoid Cells are Associated With Disease Activity and Arthritis Involvement in Patients With Systemic Lupus Erythematosus

Objectives

This study aims to evaluate the frequency and absolute number of circulating innate lymphoid cell (ILC) subsets and their associations with clinical and serological features in systemic lupus erythematosus (SLE).

Patients and methods

We recruited 28 SLE patients (6 males, 22 females; mean age 37.57 years; range, 18 to 56 years) and 13 healthy controls (4 males, 9 females; mean age 32.08 years; range, 19 to 48 years). Circulating ILC subsets were identified by flow cytometry. Associations between all detected cells and SLE disease activity, clinical manifestations, and serum autoantibodies were analyzed.

Results

In this study, significantly higher frequencies of ILC2s and ILC3s, lower frequencies of ILC1s, and higher ILC1/ILC3 and ILC1/ILC2 ratios were observed in SLE patients than in healthy controls. The frequencies and number of ILC3s were positively associated with SLE disease activity index 2000 score and anti-double stranded deoxyribonucleic acid titers in patients with SLE. Decreased ILC1 frequencies, increased ILC3 frequencies, and decreased ILC1/ILC3 and ILC2/ILC3 ratios were observed in patients with arthritis compared to those without arthritis.

Conclusion

Our results indicated biased altered distributions of circulating ILC subsets in SLE. ILC3s were associated with SLE disease activity, and ILC1s, ILC3s, and ILC1/ILC3 and ILC2/ILC3 ratios were associated with SLE accompanied with arthritis. Taken together, these results suggest that ILCs may serve as cellular biomarkers for disease activity and arthritis involvement in SLE.

Phosphorylation of SNX27 by MAPK11/14 links cellular stress-signaling pathways with endocytic recycling

Endocytosed proteins can be delivered to lysosomes for degradation or recycled to either the trans-Golgi network or the plasma membrane. It remains poorly understood how the recycling versus degradation of cargoes is determined. Here, we show that multiple extracellular stimuli, including starvation, LPS, IL-6, and EGF treatment, can strongly inhibit endocytic recycling of multiple cargoes through the activation of MAPK11/14. The stress-induced kinases in turn directly phosphorylate SNX27, a key regulator of endocytic recycling, at serine 51 (Ser51). Phosphorylation of SNX27 at Ser51 alters the conformation of its cargo-binding pocket and decreases the interaction between SNX27 and cargo proteins, thereby inhibiting endocytic recycling. Our study indicates that endocytic recycling is highly dynamic and can crosstalk with cellular stress–signaling pathways. Suppression of endocytic recycling and enhancement of receptor lysosomal degradation serve as new mechanisms for cells to cope with stress and save energy.

Computational flow cytometric analysis to detect epidermal subpopulations in human skin

Background

The detection and dissection of epidermal subgroups could lead to an improved understanding of skin homeostasis and wound healing. Flow cytometric analysis provides an effective method to detect the surface markers of epidermal cells while producing high-dimensional data files.

Methods

A 9-color flow cytometric panel was optimized to reveal the heterogeneous subgroups in the epidermis of human skin. The subsets of epidermal cells were characterized using automated methods based on dimensional reduction approaches (viSNE) and clustering with Spanning-tree Progression Analysis of Density-normalized Events (SPADE).

Results

The manual analysis revealed differences in epidermal distribution between body sites based on a series biaxial gating starting with the expression of CD49f and CD29. The computational analysis divided the whole epidermal cell population into 25 clusters according to the surface marker phenotype with SPADE. This automatic analysis delineated the differences between body sites. The consistency of the results was confirmed with PhenoGraph.

Conclusion

A multicolor flow cytometry panel with a streamlined computational analysis pipeline is a feasible approach to delineate the heterogeneity of the epidermis in human skin.

Emerging role of NIK/IKK2-binding protein (NIBP)/trafficking protein particle complex 9 (TRAPPC9) in nervous system diseases

NFκB signaling and protein trafficking network play important roles in various biological and pathological processes. NIK-and-IKK2-binding protein (NIBP), also known as trafficking protein particle complex 9 (TRAPPC9), is a prototype member of a novel protein family, and has been shown to regulate both NFκB signaling pathway and protein transport/trafficking. NIBP is extensively expressed in the nervous system and plays an important role in regulating neurogenesis and neuronal differentiation. NIBP/TRAPPC9 mutations have been linked to an autosomal recessive intellectual disability syndrome, called NIBP Syndrome, which is characterized by nonsyndromic autosomal recessive intellectual disability along with other symptoms such as obesity, microcephaly, and facial dysmorphia. As more cases of NIBP Syndrome are identified, new light is being shed on the role of NIBP/TRAPPC9 in the central nervous system developments and diseases. NIBP is also involved in the enteric nervous system. This review will highlight the importance of NIBP/TRAPPC9 in central and enteric nervous system diseases, and the established possible mechanisms for developing a potential therapeutic.

Structure of TBC1D23 N-terminus reveals a novel role for rhodanese domain

Members of the Tre2-Bub2-Cdc16 (TBC) family often function to regulate membrane trafficking and to control signaling transductions pathways. As a member of the TBC family, TBC1D23 is critical for endosome-to-Golgi cargo trafficking by serving as a bridge between Golgi-bound golgin-97/245 and the WASH/FAM21 complex on endosomal vesicles. However, the exact mechanisms by which TBC1D23 regulates cargo transport are poorly understood. Here, we present the crystal structure of the N-terminus of TBC1D23 (D23N), which consists of both the TBC and rhodanese domains. We show that the rhodanese domain is unlikely to be an active sulfurtransferase or phosphatase, despite containing a putative catalytic site. Instead, it packs against the TBC domain and forms part of the platform to interact with golgin-97/245. Using the zebrafish model, we show that impacting golgin-97/245-binding, but not the putative catalytic site, impairs neuronal growth and brain development. Altogether, our studies provide structural and functional insights into an essential protein that is required for organelle-specific trafficking and brain development.

Correction: Loss of ZNF32 augments the regeneration of nervous lateral line system through negative regulation of SOX2 transcription

[This corrects the article DOI: 10.18632/oncotarget.11895.].

Systematic genome editing of the genes on zebrafish Chromosome 1 by CRISPR/Cas9

Genome editing by the well-established CRISPR/Cas9 technology has greatly facilitated our understanding of many biological processes. However, a complete whole-genome knockout for any species or model organism has rarely been achieved. Here, we performed a systematic knockout of all the genes (1333) on Chromosome 1 in zebrafish, successfully mutated 1029 genes, and generated 1039 germline-transmissible alleles corresponding to 636 genes. Meanwhile, by high-throughput bioinformatics analysis, we found that sequence features play pivotal roles in effective gRNA targeting at specific genes of interest, while the success rate of gene targeting positively correlates with GC content of the target sites. Moreover, we found that nearly one-fourth of all mutants are related to human diseases, and several representative CRISPR/Cas9-generated mutants are described here. Furthermore, we tried to identify the underlying mechanisms leading to distinct phenotypes between genetic mutants and antisense morpholino-mediated knockdown embryos. Altogether, this work has generated the first chromosome-wide collection of zebrafish genetic mutants by the CRISPR/Cas9 technology, which will serve as a valuable resource for the community, and our bioinformatics analysis also provides some useful guidance to design gene-specific gRNAs for successful gene editing.

Intracellular selection of trans-cleaving hammerhead ribozymes

Hammerhead ribozyme is the smallest and best characterized catalytic RNA-cleaving ribozyme. It has been reported as potential therapeutic tools to manipulate the expression of target genes. However, most of naturally occurring hammerhead ribozymes process self-cleavage rather than cleave substrate RNA in trans, and its high intracellular activity relies on the tertiary interaction of Loop II and steam I bulge, resulting in decreased performance as applied in gene silencing. We described a direct intracellular selection method to evolve hammerhead variants based on trans-cleavage mode via using a toxin gene as the reporter. And a dual fluorescence proteins system has also been established to quantitatively evaluate the efficiency of selected ribozymes in the cell. Based on this selection strategy, we obtained three mutants with enhanced intracellular cleaving activity compared to wide type hammerhead ribozyme. The best one, TX-2 was revealed to possess better and consistent gene knockdown ability at different positions on diverse targeted mRNA either in prokaryotic or eukaryotic cells than wild-type hammerhead ribozyme. These observations imply the efficiency of the intracellular selection method of the trans-acting ribozyme and the potentials of improved ribozyme variants for research and therapeutic purposes.

ZNF424 Induces Apoptosis and Inhibits Proliferation in Lung Carcinoma Cells

Background:

Previously, we showed that the Zinc finger-containing transcription factor ZNF424 inhibits p21 transcription, which has been widely associated with various cancers. However, because the roles of ZNF424 in tumorigenesis have not been characterized, we correlated ZNF424 expression with tumorigenesis in lung cancer.

Results:

The present immunohistochemical analyses show significantly lower ZNF424 expression levels in 43 of 60 lung cancer tissues compared with adjacent tissues. Moreover, flow cytometry assays indicated that overexpression of ZNF424 induces apoptosis in A549 human lung carcinoma cells, and overexpression of ZNF424 significantly increases numbers of G1 phase cells and decreases numbers of S phase cells, suggesting that ZNF424 inhibits proliferation. Western Blot analyses show that overexpression of ZNF424 decreases protein expression levels of the mitogen-activated protein kinase (MAPK) signaling proteins P-P38 and P-ERK in A549 cells.

Conclusion:

These are the first data to associate ZNF424 with tumorigenesis and demonstrate an inhibitory role in lung cancer, indicating the potential of ZNF424 expression as a diagnostic marker of lung tumorigenesis.

[SIVA1 Regulates the Stability of Single-Stranded DNA-Binding Protein 3 Isoforms]

The assembly of LIM-homeodomain (LIM-HD) transcriptional complex plays important roles in early neuronal development. The stability of LIM-HD is controlled by single-strand binding protein 3 (SSBP3) via a cascade mechanism protecting it from proteasomal degradation. The expression level of SSBP3 has to be precisely regulated. Although a decrease of SSBP3 level is associated with several diseases, the mechanism of SSBP3 downregulation and whether SSBP3 itself is subject to proteasomal degradation remain largely unknown. Two strongly conserved transcripts of the SSBP3 gene, SSBP3a and SSBP3c, were cloned from a human brain cDNA library. By RT-PCR, we show that Ssbp3c is continuously expressed in both embryonic and adult mouse brain, whereas Ssbp3a is restricted to embryonic brain tissue. By co-IP and GST pulldown assays, we identified SIVA1 as a novel SSBP3-binding factor. In a ubiquitination assay, we show that SIVA1 enhances the ubiquitination of SSBP3 and regulates its abundance. Our findings reveal the proteasomal degradation of SSBP3 for the first time and provide a rationale for an SIVAl-SSBP3-dependent mechanism for the disassembly of LIM-HD multiprotein complexes.

The bHLH Protein Nulp1 is Essential for Femur Development Via Acting as a Cofactor in Wnt Signaling in Drosophila

Background:

The basic helix-loop-helix (bHLH) protein families are a large class of transcription factors, which are associated with cell proliferation, tissue differentiation, and other important development processes. We reported that the Nuclear localized protein-1 (Nulp1) might act as a novel bHLH transcriptional factor to mediate cellular functions. However, its role in development in vivo remains unknown.

Methods:

Nulp1 (dNulp1) mutants are generated by CRISPR/Cas9 targeting the Domain of Unknown Function (DUF654) in its C terminal. Expression of Wg target genes are analyzed by qRT-PCR. We use the Top-Flash luciferase reporter assay to response to Wg signaling.

Results:

Here we show that Drosophila Nulp1 (dNulp1) mutants, generated by CRISPR/Cas9 targeting the Domain of Unknown Function (DUF654) in its C terminal, are partially homozygous lethal and the rare escapers have bent femurs, which are similar to the major manifestation of congenital bent-bone dysplasia in human Stuve-Weidemann syndrome. The fly phenotype can be rescued by dNulp1 over-expression, indicating that dNulp1 is essential for fly femur development and survival. Moreover, dNulp1 overexpression suppresses the notch wing phenotype caused by the overexpression of sgg/GSK3β, an inhibitor of the canonical Wnt cascade. Furthermore, qRT-PCR analyses show that seven target genes positively regulated by Wg signaling pathway are down-regulated in response to dNulp1 knockout, while two negatively regulated Wg targets are up-regulated in dNulp1 mutants. Finally, dNulp1 overexpression significantly activates the Top-Flash Wnt signaling reporter.

Conclusion:

We conclude that bHLH protein dNulp1 is essential for femur development and survival in Drosophila by acting as a positive cofactor in Wnt/Wingless signaling.

Role of Zebrafish fhl1A in Satellite Cell and Skeletal Muscle Development

Background:

Four-and-a-half LIM domains protein 1 (FHL1) mutations are associated with human myopathies. However, the function of this protein in skeletal development remains unclear.

Methods:

Whole-mount in situ hybridization and embryo immunostaining were performed.

Results:

Zebrafish Fhl1A is the homologue of human FHL1. We showed that fhl1A knockdown causes defective skeletal muscle development, while injection with fhl1A mRNA largely recovered the muscle development in these fhl1A morphants. We also demonstrated that fhl1A knockdown decreases the number of satellite cells. This decrease in satellite cells and the emergence of skeletal muscle abnormalities were associated with alterations in the gene expression of myoD, pax7, mef2ca and skMLCK. We also demonstrated that fhl1A expression and retinoic acid (RA) signalling caused similar skeletal muscle development phenotypes. Moreover, when treated with exogenous RA, endogenous fhl1A expression in skeletal muscles was robust. When treated with DEAB, an RA signalling inhibitor which inhibits the activity of retinaldehyde dehydrogenase, fhl1A was downregulated.

Conclusion:

fhl1A functions as an activator in regulating the number of satellite cells and in skeletal muscle development. The role of fhl1A in skeletal myogenesis is regulated by RA signaling.

Circulating Tissue Factor-Positive Procoagulant Microparticles in Patients with Type 1 Diabetes

AIM

To investigate the count of circulating tissue factor-positive (TF⁺) procoagulant microparticles (MPs) in patients with type 1 diabetes mellitus (T1DM).

METHODS

This case-control study included patients with T1DM and age and sex-matched healthy volunteers. The counts of phosphatidylserine-positive (PS⁺) MPs and TF⁺PS⁺MPs and the subgroups derived from different cell types were measured in the peripheral blood sample of the two groups using multicolor flow cytometric assay. We compared the counts of each MP between groups as well as the ratio of the TF⁺PS⁺MPs and PS⁺MPs (TF⁺PS⁺MPs/PS⁺MPs).

RESULTS

We recruited 36 patients with T1DM and 36 matched healthy controls. Compared with healthy volunteers, PS⁺MPs, TF⁺PS⁺MPs and TF⁺PS⁺MPs/PS⁺MPs were elevated in patients with T1DM (PS⁺MPs: 1078.5 ± 158.08 vs 686.84 ± 122.04/μL, P <0.001; TF⁺PS⁺MPs: 202.10 ± 47.47 vs 108.33 ± 29.42/μL, P <0.001; and TF⁺PS⁺MPs/PS⁺MPs: 0.16 ± 0.04 vs 0.19 ± 0.05, P = 0.004), mostly derived from platelet, lymphocytes and endothelial cells. In the subgroup analysis, the counts of total and platelet TF⁺PS⁺MPs were increased in patients with diabetic retinopathy (DR) and with higher HbA1c, respectively.

CONCLUSION

Circulating TF⁺PS⁺MPs and those derived from platelet, lymphocytes and endothelial cells were elevated in patients with T1DM.

Verteporfin blocks Clusterin which is required for survival of gastric cancer stem cell by modulating HSP90 function

Gastric cancer stem cell (GCSC) is implicated in gastric cancer relapse, metastasis and drug resistance. However, the key molecule(s) involved in GCSC survival and the targeting drugs are poorly understood. We discovered increased secreted clusterin (S-Clu) protein expression during the sphere-forming growth of GCSC via mass spectrometry. Overexpression of clusterin was detected in 69/90 (77%) of primary GC tissues and significantly associated with T stage, lymph node metastasis and TNM stage. Depletion of clusterin (Clu, the full-length intracellular clusterin) led to the declustering of GCSC tumorspheres and apoptosis of GCSC. Subsequently, we found clusterin was in complex with heat shock protein 90 beta (HSP90) and involved in regulating the cellular level of HSP90 client proteins. Furthermore, by screening a collection of drugs/inhibitors, we found that verteporfin (VP), a phototherapy drug, blocked clusterin gene expression, decreased the HSP90 client proteins and caused cell death of GCSC. VP treatment is more effective in eradicating GCSCs than in killing GC cells. Both clusterin silencing or VP treatment deterred tumor growth in human GCSC xenografts. These findings collectively suggest that GC patients can promptly benefit from clusterin-targeted therapy as well as VP treatment in combination with or subsequent to conventional chemotherapy for reducing mortality of GC.

Mid1ip1b modulates apical reorientation of non-centrosomal microtubule organizing center in epithelial cells

In most kinds of animal cells, the centrosome serves as the main microtubule organizing center (MTOC) that nucleates microtubule arrays throughout the cytoplasm to maintain cell structure, cell division and intracellular transport. Whereas in epithelial cells, non-centrosomal MTOCs are established in the apical domain for generating asymmetric microtubule fibers and cilia in epithelial cells for the organ morphogenesis during embryonic development. However, the mechanism by which MTOCs localize to the apical domain in epithelial cells remains largely unknown. Here, we show that Mid1ip1b has a close interaction with γ-tubulin protein, the central component of MTOC, and modulates lumen opening of the neural tube, gut, intestine, and kidney of zebrafish. Knockdown or dominant negative effect of Mid1ip1b resulted in failure of lumen formation of the organs as aforementioned. Moreover, the non-centrosomal MTOCs were unable to orientate to the apical domain in Mid1ip1b knockdown epithelial cells, and the centrosomal MTOCs were inaccurately placed in the apical domain, resulting in defective formation of asymmetric microtubules and misplacement of cilia in the apical domain. These data uncover a molecule that controls the proper localization of MTOCs in the apical domain in epithelial cells for organ morphogenesis during embryonic development.

Synergy between peroxisome proliferator-activated receptor γ agonist and radiotherapy in cancer

Angiogenesis and inflammation are crucial processes through which the tumor microenvironment (TME) influences tumor progression. In this study, we showed that peroxisome proliferator‐activated receptor γ (PPARγ) is not only expressed in CT26 and 4T1 tumor cell lines but also in cells of TME, including endothelial cells and tumor‐associated macrophages (TAM). In addition, we showed that rosiglitazone may induce tumor vessel normalization and reduce TAM infiltration. Additionally, 4T1 and CT26 tumor‐bearing mice treated with rosiglitazone in combination with radiotherapy showed a significant reduction in lesion size and lung metastasis. We reported that a single dose of 12 Gy irradiation strongly inhibits local tumor angiogenesis. Secretion of C‐C motif chemokine ligand 2 (CCL2) in response to local irradiation facilitates the recruitment of migrating CD11b⁺ myeloid monocytes and TAM to irradiated sites that initiate vasculogenesis and enable tumor recurrence after radiotherapy. We found that rosiglitazone partially decreases CCL2 secretion by tumor cells and reduces the infiltration of CD11b⁺ myeloid monocytes and TAM to irradiated tumors, thereby delaying tumor regrowth after radiotherapy. Therefore, combination of the PPARγ agonist rosiglitazone with radiotherapy enhances the effectiveness of radiotherapy to improve local tumor control, decrease distant metastasis risks and delay tumor recurrence.