Integrating trans-omics, cellular experiments and clinical validation to identify ILF2 as a diagnostic serum biomarker and therapeutic target in gastric cancer

BACKGROUND

Gastric cancer (GC) lacks serum biomarkers with clinical diagnostic value. Multi-omics analysis is an important approach to discovering cancer biomarkers. This study aimed to identify and validate serum biomarkers for GC diagnosis by cross-analysis of proteomics and transcriptomics datasets.

METHODS

A cross-omics analysis was performed to identify overlapping differentially expressed genes (DEGs) between our previous aptamer-based GC serum proteomics dataset and the GC tissue RNA-Seq dataset in The Cancer Genome Atlas (TCGA) database, followed by lasso regression and random forest analysis to select key overlapping DEGs as candidate biomarkers for GC. The mRNA levels and diagnostic performance of these candidate biomarkers were analyzed in the original and independent GC datasets to select valuable candidate biomarkers. The valuable candidate biomarkers were subjected to bioinformatics analysis to select those closely associated with the biological behaviors of GC as potential biomarkers. The clinical diagnostic value of the potential biomarkers was validated using serum samples, and their expression levels and functions in GC cells were validated using in vitro cell experiments.

RESULTS

Four candidate biomarkers (ILF2, PGM2L1, CHD7, and JCHAIN) were selected. Their mRNA levels differed significantly between tumor and normal tissues and showed different diagnostic performances for GC, with areas under the receiver operating characteristic curve (AUROCs) of 0.629-0.950 in the TCGA dataset and 0.736-0.840 in the Gene Expression Omnibus (GEO) dataset. In the bioinformatics analysis, only ILF2 (interleukin enhancer-binding factor 2) gene levels were associated with immune cell infiltration, some checkpoint gene expression, chemotherapy sensitivity, and immunotherapy response. Serum levels of ILF2 were higher in GC patients than in controls, with an AUROC of 0.944 for the diagnosis of GC, and it was also detected in the supernatants of GC cells. Knockdown of ILF2 by siRNA significantly reduced the proliferation and colony formation of GC cells. Overexpression of ILF2 significantly promotes the proliferation and colony formation of gastric cancer cells.

CONCLUSIONS

Trans-omics analysis of proteomics and transcriptomics is an efficient approach for discovering serum biomarkers, and ILF2 is a potential diagnostic biomarker and therapeutic target of gastric cancer.

mTORC2-AKT signaling to PFKFB2 activates glycolysis that enhances stemness and tumorigenicity of intestinal epithelial cells

Although elevated glycolysis has been widely recognized as a hallmark for highly proliferating cells like stem cells and cancer, its regulatory mechanisms are still being updated. Here, we found a previously unappreciated mechanism of mammalian target of rapamycin complex 2 (mTORC2) in regulating glycolysis in intestinal stem cell maintenance and cancer progression. mTORC2 key subunits expression levels and its kinase activity were specifically upregulated in intestinal stem cells, mouse intestinal tumors, and human colorectal cancer (CRC) tissues. Genetic ablation of its key scaffolding protein Rictor in both mouse models and cell lines revealed that mTORC2 played an important role in promoting intestinal stem cell proliferation and self-renewal. Moreover, utilizing mouse models and organoid culture, mTORC2 loss of function was shown to impair growth of gut adenoma and tumor organoids. Based on these findings, we performed RNA-seq and noticed significant metabolic reprogramming in Rictor conditional knockout mice. Among all the pathways, carbohydrate metabolism was most profoundly altered, and further studies demonstrated that mTORC2 promoted glycolysis in intestinal epithelial cells. Most importantly, we showed that a rate-limiting enzyme in regulating glycolysis, 6-phosphofructo-2-kinase (PFKFB2), was a direct target for the mTORC2-AKT signaling. PFKFB2 was phosphorylated upon mTORC2 activation, but not mTORC1, and this process was AKT-dependent. Together, this study has identified a novel mechanism underlying mTORC2 activated glycolysis, offering potential therapeutic targets for treating CRC.

The Index sAGP is Valuable for Distinguishing Atypical Hepatocellular Carcinoma from Atypical Benign Focal Hepatic Lesions

Purpose

The differential diagnosis of atypical hepatocellular carcinoma (aHCC) and atypical benign focal hepatic lesions (aBFHL) usually depends on pathology. This study aimed to develop non-invasive approaches based on conventional blood indicators for the differential diagnosis of aHCC and aBFHL.

Patients and Methods

Hospitalized patients with pathologically confirmed focal hepatic lesions and their clinical data were retrospectively collected, in which patients with HCC with serum alpha-fetoprotein (AFP) levels of ≤200 ng/mL and atypical imaging features were designated as the aHCC group (n = 224), and patients with benign focal hepatic lesions without typical imaging features were designated as the aBFHL group (n = 178). The performance of indexes (both previously reported and newly constructed) derived from conventional blood indicators by four mathematical operations in distinguishing aHCC and aBFHL was evaluated using the receiver operating characteristic (ROC) curve and diagnostic validity metrics.

Results

Among ten previously reported derived indexes related to HCC, the index GPR, the ratio of γ-glutamyltransferase (GGT) to platelet (PLT), showed the best performance in distinguishing aHCC from aBFHL with the area under ROC curve (AUROC) of 0.853 (95% CI 0.814-0.892), but the other indexes were of little value (AUROCs from 0.531 to 0.700). A new derived index, sAGP [(standardized AFP + standardized GGT)/standardized PLT], was developed and exhibited AUROCs of 0.905, 0.894, 0.891, 0.925, and 0.862 in differentiating overall, BCLC stage 0/A, TNM stage I, small, and AFP-negative aHCC from aBFHL, respectively.

Conclusion

The sAGP index is an efficient, simple, and practical metric for the non-invasive differentiation of aHCC from aBFHL.

Excessive nucleic acid R-loops induce mitochondria-dependent epithelial cell necroptosis and drive spontaneous intestinal inflammation

Oxidative stress, which can be activated by a variety of environmental risk factors, has been implicated as an important pathogenic factor for inflammatory bowel disease (IBD). However, how oxidative stress drives IBD onset remains elusive. Here, we found that oxidative stress was strongly activated in inflamed tissues from both ulcerative colitis patients and Crohn's disease patients, and it caused nuclear-to-cytosolic TDP-43 transport and a reduction in the TDP-43 protein level. To investigate the function of TDP-43 in IBD, we inducibly deleted exons 2 to 3 of Tardbp (encoding Tdp-43) in mouse intestinal epithelium, which disrupted its nuclear localization and RNA-processing function. The deletion gave rise to spontaneous intestinal inflammation by inducing epithelial cell necroptosis. Suppression of the necroptotic pathway with deletion of Mlkl or the RIP1 inhibitor Nec-1 rescued colitis phenotypes. Mechanistically, disruption of nuclear TDP-43 caused excessive R-loop accumulation, which triggered DNA damage and genome instability and thereby induced PARP1 hyperactivation, leading to subsequent NAD+ depletion and ATP loss, consequently activating mitochondrion-dependent necroptosis in intestinal epithelial cells. Importantly, restoration of cellular NAD+ levels with NAD+ or NMN supplementation, as well as suppression of ALKBH7, an α-ketoglutarate dioxygenase in mitochondria, rescued TDP-43 deficiency-induced cell death and intestinal inflammation. Furthermore, TDP-43 protein levels were significantly inversely correlated with γ-H2A.X and p-MLKL levels in clinical IBD samples, suggesting the clinical relevance of TDP-43 deficiency-induced mitochondrion-dependent necroptosis. Taken together, these findings identify a unique pathogenic mechanism that links oxidative stress to intestinal inflammation and provide a potent and valid strategy for IBD intervention.

Randomized phase II adjuvant trial to compare two treatment durations of icotinib (2 years versus 1 year) for stage II-IIIA EGFR-positive lung adenocarcinoma patients (ICOMPARE study)

BACKGROUND

Despite the prolonged median disease-free survival (DFS) by adjuvant targeted therapy in non-small-cell lung cancer patients with epidermal growth factor receptor (EGFR) mutations, the relationship between the treatment duration and the survival benefits in patients remains unknown.

PATIENTS AND METHODS

In this multicenter, randomized, open-label, phase II trial, eligible patients aged 18-75 years with EGFR-mutant, stage II-IIIA lung adenocarcinoma and who had not received adjuvant chemotherapy after complete tumor resection were enrolled from eight centers in China. Patients were randomly assigned (1 : 1) to receive either 1-year or 2-year icotinib (125 mg thrice daily). The primary endpoint was DFS assessed by investigator. The secondary endpoints were overall survival (OS) and safety. This study was registered at ClinicalTrials.gov (NCT01929200).

RESULTS

Between September 2013 and October 2018, 109 patients were enrolled (1-year group, n = 55; 2-year group, n = 54). Median DFS was 48.9 months [95% confidence interval (CI) 33.1-70.1 months] in the 2-year group and 32.9 months (95% CI 26.6-44.8 months) in the 1-year group [hazard ratio (HR) 0.51; 95% CI 0.28-0.94; P = 0.0290]. Median OS for patients was 75.8 months [95% CI 64.4 months-not evaluable (NE)] in the 2-year group and NE (95% CI 66.3 months-NE) in the 1-year group (HR 0.34; 95% CI 0.13-0.95; P = 0.0317). Treatment-related adverse events (TRAEs) were observed in 41 of 55 (75%) patients in the 1-year group and in 36 of 54 (67%) patients in the 2-year group. Grade 3-4 TRAEs occurred in 4 of 55 (7%) patients in the 1-year group and in 3 of 54 (6%) patients in the 2-year group. No treatment-related deaths or interstitial lung disease was reported.

CONCLUSIONS

Two-year adjuvant icotinib was shown to significantly improve DFS and provide an OS benefit in EGFR-mutant, stage II-IIIA lung adenocarcinoma patients compared with 1-year treatment in this exploratory phase II study.

Analysis of aptamer-target binding and molecular mechanisms by thermofluorimetric analysis and molecular dynamics simulation

Introduction: Aptamers are valuable for bioassays, but aptamer-target binding is susceptible to reaction conditions. In this study, we combined thermofluorimetric analysis (TFA) and molecular dynamics (MD) simulations to optimize aptamer-target binding, explore underlying mechanisms and select preferred aptamer. Methods: Alpha-fetoprotein (AFP) aptamer AP273 (as the model) was incubated with AFP under various experimental conditions, and melting curves were measured in a real-time PCR system to select the optimal binding conditions. The intermolecular interactions of AP273-AFP were analysed by MD simulations with these conditions to reveal the underlying mechanisms. A comparative study between AP273 and control aptamer AP-L3-4 was performed to validate the value of combined TFA and MD simulation in selecting preferred aptamers. Results: The optimal aptamer concentration and buffer system were easily determined from the dF/dT peak characteristics and the melting temperature (Tm) values on the melting curves of related TFA experiments, respectively. A high Tm value was found in TFA experiments performed in buffer systems with low metal ion strength. The molecular docking and MD simulation analyses revealed the underlying mechanisms of the TFA results, i.e., the binding force and stability of AP273 to AFP were affected by the number of binding sites, frequency and distance of hydrogen bonds, and binding free energies; these factors varied in different buffer and metal ion conditions. The comparative study showed that AP273 was superior to the homologous aptamer AP-L3-4. Conclusion: Combining TFA and MD simulation is efficient for optimizing the reaction conditions, exploring underlying mechanisms, and selecting aptamers in aptamer-target bioassays.

Age-Related Mucus Barrier Dysfunction in Mice Is Related to the Changes in Muc2 Mucin in the Colon

During aging, the protective function of mucus barrier is significantly reduced among which changes in colonic mucus barrier function received the most attention. Additionally, the incidence of colon-related diseases increases significantly in adulthood, posing a threat to the health of the elderly. However, the specific changes in colonic mucus barrier with aging and the underlying mechanisms have not been fully elucidated. To understand the effects of aging on the colonic mucus barrier, changes in the colonic mucus layer were evaluated in mice aged 2, 12, 18, and 24 months. Microbial invasion, thickness, and structure of colonic mucus in mice at different months of age were analyzed by in situ hybridization fluorescence staining, AB/PAS staining, and cryo-scanning electron microscopy. Results showed that the aged colon exhibited intestinal mucus barrier dys-function and altered mucus properties. During aging, microorganisms invaded the mucus layer to reach epithelial cells. Compared with young mice, the thickness of mucus layer in aged mice in-creased by 11.66 μm. And the contents of the main components and glycosylation structure of colon changed. Among them, the proportion of goblet cells decreased significantly in older mice, and the expression of spdef genes that regulate goblet cell differentiation decreased. Further, the expression of key enzymes involved in mucin core structure formation and glycan modification also changed with aging. The expression of core 1 β1,3-galactosyltransferase (C1GalT1) which is the key enzyme forming the main core structure increased by one time, while core 2 β1,6 N-acetylglucosaminyltransferase (C2GnT) and core 3 β1,3 N-acetylglucosaminyltransferase (C3GnT) decreased 2 to 6- and 2-fold, respectively. Also, the expression of sialyltransferase, one of the mucin-glycan modifying enzymes, was decreased by 1-fold. Overall, our results indicate that the goblet cells/glycosyltransferase/O-glycan axis plays an important role in maintaining the physicochemical properties of colonic mucus and the stability of intestinal environment.

Copper-Catalyzed Transamidation of Unactivated Secondary Amides via C-H and C-N Bond Simultaneous Activations

Here, we demonstrate that α-C-H and C-N bonds of unactivated secondary amides can be activated simultaneously by the copper catalyst to synthesize α-ketoamides or α-ketoesters in one step, which is a challenging and underdeveloped transformation. Using copper as a catalyst and air as an oxidant, the reaction is compatible with a broad range of acetoamides, amines, and alcohols. The preliminary mechanism studies and density functional theory calculation indicated that the reaction process may undergo first radical α-oxygenation and then transamidation with the help of the resonant six-membered N,O-chelation and molecular oxygen plays a role as an initiator to trigger the transamidation process. The combination of chelation assistance and dioxygen selective oxygenation strategy would substantially extend the modern mild synthetic amide cleavage toolbox, and we envision that this broadly applicable method will be of great interest in the biopharmaceutical industry, synthetic chemistry, and agrochemical industry.

Interim connection space based on colorimetric values for spectral image compression and reproduction

A new interim and connection space (ICS) and its reconstruction method are proposed. The proposed ICS,t_D65A, consists of six colorimetric values or two sets of tristimulus values under CIE illuminant D65 and A respectively. In addition, a new spectral decomposition based on the t_D65A ICS and the Wiener Estimation matrix M_W was introduced for an improved spectral reconstruction. Accompanying the t_D65A ICS, m important basis vectors for the metameric black space based on the new spectral decomposition, and a mapping matrix M_P,k via a polynomial model of order k, were trained so that both the spectral and colorimetric accuracies for the reconstructed reflectance can be further enhanced. The proposed ICS and its reconstruction method can ensure exact colorimetric matches under two (real rather than synthetic) illuminants D65 and A, which is an advantage compared with other ICSs. The performance of the proposed method was tested and compared with five other ICSs using the NCS dataset and three spectral images respectively, using RMSE and GFC to measure the spectral accuracy, and using CIEDE2000 colour differences to measure the colorimetric accuracy under three types of illuminants (continuous, fluorescent, and LED). Performance test results showed the proposed methods outperform other ICSs in terms of both spectral accuracy and colorimetric measures (RMSE, GFC, and CIEDE2000 colour difference). Therefore, it is expected the proposed ICS and its reconstruction method can play an important role in spectral image compression and reproduction applications.

Riemann-Hilbert approach to two-component modified short-pulse system and its nonlocal reductions

In this paper, a Riemann-Hilbert approach to a two-component modified short-pulse (mSP) system on the line with zero boundary conditions is developed. A parametric representation of the solution to the related Cauchy problem is obtained. Four nonlocal integrable reductions, namely, the real reverse space-time nonlocal focusing and defocusing mSP equations and the complex reverse space-time nonlocal focusing and defocusing mSP equations, are studied in detail. For each case, soliton solutions are presented, and, unlike their local counterparts, the nonlocal equations exhibit certain novel properties induced by the impact of nonlocality.

A Topical Emollient Mitigates the Progression of Cognitive Impairment in the Elderly: A Randomized, Open-Label Pilot Trial

BACKGROUND

Cognitive impairment is common in the elderly. Prior studies suggest a link between chronic inflammation and cognitive dysfunction, while aging-associated epidermal dysfunction has been connected to elevations in circulating cytokines.

OBJECTIVE

We assessed here whether improvements in epidermal function can mitigate the progression of cognitive impairment.

METHODS

This randomized, open-label pilot trial was carried out in two cities in northern China. A total of 200 participants aged ≥65 years were randomly assigned to the emollient-treated and untreated groups at 1:1 ratio. Participants in the treated group were treated topically with Atopalm cream® twice-daily from November to the following May each year for three consecutive years, while the untreated subjects served as controls. The Global Deterioration Scale (GDS) was used to assess the severity of cognitive impairment, while epidermal biophysical properties were measured on the forearms and the shins in parallel.

RESULTS

Over the three-year trial, GDS significantly increased from baseline (p<0.0001) in the controls, while in the treated group, GDS stabilized. While stratum corneum hydration on the forearms did not change significantly in the controls, transepidermal water loss rates (TEWL), significantly increased by the end of the trial compared to baselines in the controls (p<0.0001). On the forearms of the treated group, stratum corneum hydration increased (p<0.0001) while skin surface pH decreased from baseline (p<0.0001).

CONCLUSIONS

These results suggest that improvements in epidermal function with topical emollient can mitigate the progression of cognitive impairment. However, the sample size was relatively small, and trials in a larger cohort are needed to validate the present results.

Nfatc1+ colonic stem cells contribute to regeneration upon colitis

BACKGROUND AND AIM

Colonic stem cells play important roles in both normal epithelial turnover and injury repair. Lgr5⁺ colonic stem cells are highly susceptible to DSS-induced damage. However, it is still unclear how colonic stem cells regenerate injured epithelium during colitis. Here, we explored the functions of a new population of NFATc1⁺ colonic stem cells in experimental colitis.

METHODS

Nfatc1⁺ colonic stem cells were labeled using Nfatc1^CreERT2 ;R26^mTmG reporter mice. Immunostaining assays were used to detect Goblet cells, enteroendocrine cells, and intestinal stem/progenitor cells. We performed lineage tracing assay to investigate whether Nfatc1⁺ cells are real colonic stem cells using Nfatc1^CreERT2 ;R26^mTmG mice. The contribution of Nfatc1⁺ stem cells on epithelial regeneration was detected in experimental colitis induced by DSS.

RESULTS

Nfatc1-reporter marked cells are enriched for +3 to +5 position in colonic crypts, and they are overlapped with Sox9⁺ cells and Hopx⁺ cells that have been identified as stem cells in small intestine. However, Nfatc1-reporter marked cells are not overlapped with Lgr5⁺ colonic stem cells, as well as differentiated goblet cells and enteroendocrine cells. Furthermore, Nfatc1-reporter marked cells are able to give rise to all lineages of the colonic epithelium, and they preferentially contribute to the regeneration of colonic epithelium in DSS-induced experimental colitis.

CONCLUSION

Nfatc1⁺ cells were identified as a novel population of colonic stem cells that are primarily located at +3 to +5 position and contribute to epithelial regeneration during colitis.

The Status of Iodine Nutrition after Removing Iodized Salt in High Water Iodine Regions: a Cross-sectional Study in China

Currently, the removal of iodized salt is carried out in high water iodine regions. The present situation of iodine nutrition and the prevalence of thyroid diseases in such regions have not been clearly elucidated. This study aimed to figure out these problems to help render effective measures for cases of abnormal iodine nutrition status. A cross-sectional study was carried out in four areas of Jining and Heze, Shandong Province, China, with different water iodine concentrations (WIC). In total, 1344 adults were enrolled in this study, and data related to their iodine nutrition, thyroid function, and thyroid ultrasonography were collected. Subjects were grouped according to WIC, urine iodine concentration (UIC), serum iodine concentration (SIC), and combined UIC and SIC for analysis. Iodine levels were in excess in the 100 μg/L ≤ WIC < 300 μg/L and WIC ≥ 300 μg/L areas. Compared with the control WIC group (10-100 μg/L), the WIC ≥ 300 μg/L group had a higher prevalence of thyroid autoimmunity (TAI, 21.25% vs. 13.19%, P <0.05), subclinical hypothyroidism (SH, 20.20% vs. 11.96%, P < 0.05), thyroid nodules (TN, 31.75% vs. 18.71%, P < 0.05), and thyroid dysfunction (23.62% vs. 12.26%, P < 0.05). Compared with the UIC control group (100-300 μg/L), high UIC group (≥ 800 μg/L) had a higher prevalence of TN (33.75% vs. 21.14%, P < 0.05) and thyroid dysfunction (25% vs. 14.47%, P < 0.05). Next, compared with the control SIC group (50-110 μg/L), high SIC group (≥ 110 μg/L) had a higher prevalence of TAI (33.80% vs. 14.47%, P < 0.05), SH (23.94% vs. 14.30%, P < 0.05), and thyroid dysfunction (33.80% vs. 15.29%, P < 0.05). Finally, subjects with the highest UIC and the highest SIC also had a higher prevalence of TAI (25.92% vs. 10.97%, P < 0.05), SH (23.45% vs. 10.97%, P < 0.05), TN (34.56% vs. 15.85%, P < 0.05), and thyroid dysfunction (27.16% vs. 13.41%, P < 0.05) than subjects with middle iodine levels. The iodine nutrition of subjects in the WIC ≥ 300 μg/L areas was still in excess after removing iodized salt from their diets. High levels of iodine also increased the prevalence of TAI, SH, TN, and thyroid dysfunction in those areas. Simply removing iodized salt may not be sufficient for high water iodine regions.

Dormant Nfatc1 reporter-marked basal stem/progenitor cells contribute to mammary lobuloalveoli formation

The Mammary gland undergoes complicated epithelial remodeling to form lobuloalveoli during pregnancy, in which basal epithelial cells remarkably increase to form a basket-like architecture. However, it remains largely unknown how dormant mammary basal stem/progenitor cells involve in lobuloalveolar development. Here, we show that Nfatc1 expression marks a rare population of mammary epithelial cells with the majority being basal epithelial cells. Nfatc1 reporter-marked basal epithelial cells are relatively dormant mammary stem/progenitor cells. Although Nfatc1 reporter-marked basal epithelial cells have limited contribution to the homeostasis of mammary epithelium, they divide rapidly during pregnancy and contribute to lobuloalveolar development. Furthermore, Nfatc1 reporter-marked basal epithelial cells are preferentially used for multiple pregnancies. Using single-cell RNA-seq analysis, we identify multiple functionally distinct clusters within the Nfatc1 reporter-marked cell-derived progeny cells during pregnancy. Taken together, our findings underscore Nfatc1 reporter-marked basal cells as dormant stem/progenitor cells that contribute to mammary lobuloalveolar development during pregnancy.

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Nfatc1 marked a subpopulation of basal dormant stem/progenitor cells

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Nfatc1-marked cells have limited contribution to the homeostasis of mammary gland

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Nfatc1 reporter-marked cells divide rapidly during pregnancy

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Nfatc1 reporter-marked cells are preferentially used for multiple pregnancies

Identifying the E2F3-MEX3A-KLF4 signaling axis that sustains cancer cells in undifferentiated and proliferative state

Rationale: Dysregulation of signaling that governs self-renewal and differentiation of intestinal stem cells (ISCs) is a major cause of colorectal cancer (CRC) initiation and progression.

Methods: qRT-PCR, western blotting, in situ hybridization, immunohistochemistry and immunofluorescence assays were used to detect the expression levels of MEX3A, KLF4 and E2F3 in CRC tissues. The biological functions of MEX3A were studied using Mex3a knockout (KO) and intestinal epithelium specific conditional knockout (cKO) mice, AOM-DSS mouse colorectal tumor model, Apc floxed mouse tumor model and intestinal and tumor organoids. Transcriptomic RNA sequencing (RNA-seq), RNA crosslinking immunoprecipitation (CLIP) and luciferase reporter assays were performed to explore the molecular mechanisms of MEX3A.

Results: RNA-binding protein MEX3A, a specific ISC marker gene, becomes ectopically upregulated upon CRC and its levels negatively correlate with patient survival prognosis. MEX3A functions as an oncoprotein that retains cancer cells in undifferentiated and proliferative status and it enhances their radioresistance to DNA damage. Mechanistically, a rate limiting factor of cellular proliferation E2F3 induces MEX3A, which in turn activates WNT pathway by directly suppressing expression of its pro-differentiation transcription factor KLF4. Knockdown of MEX3A with siRNA or addition of KLF4 agonist significantly suppressed tumor growth both by increasing differentiation status of cancer cells and by suppressing their proliferation.

Conclusions: It identifies E2F3-MEX3A-KLF4 axis as an essential coordinator of cancer stem cell self-renewal and differentiation, representing a potent new druggable target for cancer differentiation therapy.

From Amides to Urea Derivatives or Carbamates with Chemospecific C-C Bond Cleavage at Room Temperature

The ureas and carbamates are common motifs in pharmaceuticals, agrochemicals, biologically active compounds and organocatalysis applications. Herein, we report a significant advance in this area and present the general method...

Lactobacillus paracasei L9 improves colitis by expanding butyrate-producing bacteria that inhibit the IL-6/STAT3 signaling pathway

Inflammatory bowel disease (IBD) is a chronic intestinal inflammation that is currently incurable. Increasing evidence indicates that supplementation with probiotics could improve the symptoms of IBD. It is scientifically significant to identify novel and valid strains for treating IBD. It has been reported that the probiotic Lactobacillus paracasei L9 (L9), which is identified from the gut of healthy centenarians, can modulate host immunity and plays an anti-allergic role. Here, we demonstrated that L9 alleviates the pathological phenotypes of experimental colitis by expanding the abundance of butyrate-producing bacteria. Oral administration of sodium butyrate in experimental colitis recapitulates the L9 anti-inflammatory phenotypes. Mechanistically, sodium butyrate ameliorated the inflammatory responses by inhibiting the IL-6/STAT3 signaling pathway in colitis. Overall, these findings demonstrated that L9 alleviates the DSS-induced colitis development by enhancing the abundance of butyrate-producing bacterial strains that produce butyrate to suppress the IL-6/STAT3 signaling pathway, providing new insight into a promising therapeutic target for the remission of IBD.

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.

The effects of aerobic exercise on the intestinal tumors and flora of the ApcMin/+ mouse

INTRODUCTION

Intestinal tumor is one of the most common tumors that seriously threaten the health of residents all over the world. Studies suggest that the imbalance of intestinal flora is associated with tumorgenesis; meanwhile, long-term regular aerobic exercise can improve the occurrence and development of tumors. However, moderate aerobic exercise affecting the development of intestinal tumors and their related flora has not been explored. Thus, the purpose of our study is to explore the effects of aerobic exercise on intestinal tumor growth and flora changes in Apc^Min/+ mice, and try to answer whether there is a correlation between them after exercise intervention.

METHODS

In this study, 18 required Apc^Min/+ mice were randomly divided into Model group (n = 6), Exercise group (n = 6), and Aspirin group (positive control, n = 6), while C57BL/6 J wild-type mice were used as the blank control group. Each group is given corresponding intervention. Weight monitoring, tumor counts, hematoxylin-eosin staining, TdT-mediated dUTP nick-end labeling (TUNEL) fluorescence assay, immunohistochemistry (IHC), fecal sampling and grouping, and bacterial 16S rDNA gene analysis were completed after 12 weeks' intervention for each group of mice.

RESULTS

As a result, we were able to show significant improvements in mice' body weight changing rates (Exercise group 8.6% higher than Model control group), tumor numbers (Exercise group 4.33 ± 0.94 vs. Model control group 7.33 ± 2.49, Then put the slides into xylenewith tumor inhibition rate 40.93%), tumor pathological staging (Exercise group mainly low-grade tumorous adenomas vs. Model group mainly high-grade adenomas), and TUNEL staining (Exercise group 8.59% higher positive rate of apoptotic cells in tumors than Model group). The 16s rRNA sequencing analysis results showed that aerobic exercise could regulate the abundance of some genus (16/149, P < 0.01), and the number of intestinal tumors correlates with changes in the abundance of some bacteria in the intestinal flora (positive correlation with probiotics abundance and negative correlation with conditioned pathogens).

DISCUSSION

Changes in flora abundance may be one of the reasons for aerobic exercise to reduce the number of intestinal tumors, probably mediated by cell apoptosis. Future studies should focus on the potential mechanism of aerobic exercise in preventing intestinal tumorgenesis, especially the molecular mechanism through intestinal flora.

CONCLUSION

Aerobic exercise has a preventive effect on intestinal tumors in Apc^Min/+ mice, and can regulate the abundance of intestinal flora.

Hormone-Responsive BMP Signaling Expands Myoepithelial Cell Lineages and Prevents Alveolar Precocity in Mammary Gland

Myoepithelial and luminal cells synergistically expand in the mammary gland during pregnancy, and this process is precisely governed by hormone-related signaling pathways. The bone morphogenetic protein (BMP) signaling pathway is now known to play crucial roles in all organ systems. However, the functions of BMP signaling in the mammary gland remain unclear. Here, we found that BMPR1a is upregulated by hormone-induced Sp1 at pregnancy. Using a doxycycline (Dox)-inducible BMPR1a conditional knockout mouse model, we demonstrated that loss of BMPR1a in myoepithelium results in compromised myoepithelial integrity, reduced mammary stem cells and precocious alveolar differentiation during pregnancy. Mechanistically, BMPR1a regulates the expression of p63 and Slug, two key regulators of myoepithelial maintenance, through pSmad1/5-Smad4 complexes, and consequently activate P-cadherin during pregnancy. Furthermore, we observed that loss of BMPR1a in myoepithelium results in the upregulation of a secreted protein Spp1 that could account for the precocious alveolar differentiation in luminal layer, suggesting a defective basal-to-luminal paracrine signaling mechanism. Collectively, these findings identify a novel role of BMP signaling in maintaining the identity of myoepithelial cells and suppressing precocious alveolar formation.

POS0320 POOR PROGNOSIS PREDICTION IN ANTI-MDA5 POSITIVE DERMATOMYOSITIS ASSOCIATED WITH INTERSTITIAL LUNG DISEASE: THE CROSS-CAR DECISION TREE MODEL

Background:

The prognosis of anti-melanoma differentiation-associated gene 5 positive dermatomyositis (anti-MDA5+ DM) – associated interstitial lung disease (ILD) is poor and heterogeneity.

Objectives:

The aim of this study was to evaluate prognostic factors and to develop a simple and generally applicable bedside decision tree model for predicting outcomes in patients with anti-MDA5+ DM and to guide treatment.

Methods:

We analyzed data for 246 anti-MDA5+ DM patients from Myositis Study Group-Jiangsu, a multicenter cohort across eighteen tertiary hospitals in Jiangsu province, from March 2019 to October 2020. The primary end point was all-cause death, and the secondary end point was occurring of rapidly progressive-ILD (rp-ILD). We used a multivariable Cox proportional hazards model to identify the independent prognostic risk factors of death and rp-ILD respectively. A decision-tree prediction model was developed by using data from 10 hospital of southern region (n=163), with validation by using contemporaneous data from northern region (n=83).

Results:

To assess the risk of rp-ILD, we developed a combined risk score, the CROSS score, that included the following values and scores: C-reactive protein (≤8mg/L, 0; >8mg/L, 3), anti-Ro52 antibody (negative, 0; positive, 4), Sex (Female, 0; Male, 2) and Short course of disease (More than 3 months, 0; Less than 3 months, 2). The mortality risk was identified by the CAR score, including C-reactive protein (≤8mg/L, 0; >8mg/L, 1), Alanine Transaminase (≤50units/L, 0; >50units/L, 1) and rp-ILD (non-rpILD, 0; rp-ILD, 3). We divided patients into three risk groups according to the CROSS score: low, 0 to 3; medium, 4 to 7; and high 8-11. And then Use of a simple decision tree prediction model permitted stratification into three different outcome prediction groups. High-risk patients had significantly higher mortality rates than low- and medium-risk patients in both discovery and validation cohorts (p < 0.0001).

Conclusion:

The CROSS-CAR decision tree model is easy to evaluate the poor prognostic risk in MDA5+ DM patients during any follow-up period. Unnecessary lung examination, such as chest CT scan and arterial blood gas analysis was avoided in low- and medium- rpILD risk patients. The special ambulance, with red cross sign tagged on car in China, may help to screen the high risk patients and to guide further treatment.

Disclosure of Interests:

None declared

MiR-22 modulates brown adipocyte thermogenesis by synergistically activating the glycolytic and mTORC1 signaling pathways

Background: Brown adipose tissue (BAT) dissipates chemical energy as heat and has the potential to be a protective strategy to prevent obesity. microRNAs (miRNAs) are emerging as important posttranscriptional factors affecting the thermogenic function of BAT. However, the regulatory mechanism underlying miRNA-mediated energy metabolism in BAT is not fully understood. Here, we explored the roles of miR-22 in BAT thermogenesis and energy metabolism.

Methods: Using global and conditional knockout mice as in vivo models and primary brown adipocytes as an in vitro system, we investigated the function of miR-22 in BAT thermogenesis in vivo and in vitro.

Results: miR-22 expression was upregulated in BAT in response to cold exposure and during brown preadipocyte differentiation. Both global and conditional knockout mice displayed BAT whitening, impaired cold tolerance, and decreased BAT thermogenesis. Moreover, we found that miR-22 deficiency impaired BAT glycolytic capacity, which is critical for thermogenesis. The mechanistic results revealed that miR-22 activated the mTORC1 signaling pathway by directly suppressing Tsc1 and concomitantly directly suppressing Hif1an, an inhibitor of Hif1α, which promotes glycolysis and maintains thermogenesis.

Conclusions: Our findings identify miR-22 as a critical regulator in the control of thermogenesis in BAT and as a potential therapeutic target for human metabolic disorders.

Comparison of therapeutic efficacy and mechanism of paclitaxel alone or in combination with methotrexate in a collagen-induced arthritis rat model

OBJECTIVE

To compare the therapeutic efficacy of paclitaxel (PTX) alone to its combination with methotrexate (MTX) on rheumatoid arthritis.

METHODS

A collagen-induced arthritis (CIA) rat model was established by induction of type II collagen. Rats were divided into blank control group, CIA model group, MTX group 1 mg/kg, PTX 1.5 mg/kg, PTX 2.5 mg/kg, PTX 3.5 mg/kg, and MTX 1 mg/kg + PTX 3.5 mg/kg, with 10 rats per group. The inflammation of the ankle joint was analyzed by H&E staining and interleukin (IL)-1β and IL‑6 expression was detected by immunohistochemistry. TUNEL assay was performed to detect synovial tissue cell apoptosis after administration of PTX and MTX either alone or in combination. TLR4 and p‑NF-κBp65 protein expression in synovial tissue and the changes of serum IL‑1β, IL‑6, IL‑12, MMP‑3, and TNFα protein factors were detected by western blot and ELISA, respectively.

RESULTS

PTX and MTX improved histopathological changes in CIA rats. Besides, the apoptosis rate of synovial tissue cells in the PTX 3.5 mg/kg group was more than that of the PTX + MTX group. Immunohistochemistry and western blot results indicated that PTX and MTX reduce the expression rate of IL‑6 and IL‑1β and downregulate TLR4 and p‑NF-κBp65 protein expression. Furthermore, TLR4 and p‑NF-κBp65 reduced the concentration of MMP‑3, IL‑12, IL‑6, IL1‑β, and TNFα.

CONCLUSION

Both PTX and MTX exert significant suppression on rheumatoid arthritis, and the combined effect of the two drugs is weaker than that of PTX alone. Moreover, intraperitoneal injection of PTX 3.5 mg/kg every other day was the optimal dose observed in this study.

The Msi1-mTOR pathway drives the pathogenesis of mammary and extramammary Paget's disease

Mammary and extramammary Paget's Diseases (PD) are a malignant skin cancer characterized by the appearance of Paget cells. Although easily diagnosed, its pathogenesis remains unknown. Here, single-cell RNA-sequencing identified distinct cellular states, novel biomarkers, and signaling pathways - including mTOR, associated with extramammary PD. Interestingly, we identified MSI1 ectopic overexpression in basal epithelial cells of human PD skin, and show that Msi1 overexpression in the epidermal basal layer of mice phenocopies human PD at histopathological, single-cell and molecular levels. Using this mouse model, we identified novel biomarkers of Paget-like cells that translated to human Paget cells. Furthermore, single-cell trajectory, RNA velocity and lineage-tracing analyses revealed a putative keratinocyte-to-Paget-like cell conversion, supporting the in situ transformation theory of disease pathogenesis. Mechanistically, the Msi1-mTOR pathway drives keratinocyte-Paget-like cell conversion, and suppression of mTOR signaling with Rapamycin significantly rescued the Paget-like phenotype in Msi1-overexpressing transgenic mice. Topical Rapamycin treatment improved extramammary PD-associated symptoms in humans, suggesting mTOR inhibition as a novel therapeutic treatment in PD.

ROR1-AS1 promotes tumorigenesis of colorectal cancer via targeting Wnt/β-catenin

OBJECTIVE

Recent studies have discovered that long noncoding RNAs (lncRNAs) play an important role in malignant tumors. In this research, lncRNA ROR1-AS1 was selected to identify how it affected the development of colorectal cancer (CRC).

PATIENTS AND METHODS

ROR1-AS1 expression was detected by Real-time quantitative polymerase chain reaction (RT-qPCR) in CRC tissue samples. ROR1-AS1 expression level and patients' overall survival time were analyzed. Functional experiments were conducted to identify the changes of biological behaviors in CRC cells after knockdown of ROR1-AS1. Moreover, we also explored the underlying mechanism.

RESULTS

Detection of ROR1-AS1 expression level in patients' tissues showed that ROR1-AS1 was higher in CRC tissues than that in adjacent ones. ROR1-AS1 expression was negatively associated with patients' overall survival time. Cell growth ability was inhibited due to knockdown of ROR1-AS1 in vitro. Moreover, cell migration and invasion abilities were repressed after ROR1-AS1 was knockdown. Furthermore, due to the knockdown of ROR1-AS1, the targeted proteins in Wnt/β-catenin signaling pathway were suppressed.

CONCLUSIONS

These results suggested that ROR1-AS1 could enhance cell metastasis and proliferation via inducing Wnt/β-catenin signaling pathway, which might offer a potential therapeutic target in CRC.

ROR1-AS1 promotes tumorigenesis of colorectal cancer via targeting Wnt/β-catenin

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "ROR1-AS1 promotes tumorigenesis of colorectal cancer via targeting Wnt/β-catenin, by T. Liao, S.-L.-M. Maierdan, C. Lv, published in Eur Rev Med Pharmacol Sci 2019; 23 (3 Suppl): 217-223-DOI: 10.26355/eurrev_201908_18650-PMID: 31389604" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/18650.

The impacts of gene polymorphisms on methotrexate in Chinese psoriatic patients

BACKGROUND

Methotrexate (MTX) is the first-line treatment for psoriasis in China. The metabolic processes of MTX include various proteins and genes. Previous studies have shown that gene polymorphisms had significant impacts on the efficacy of MTX. However, the influence of gene polymorphisms has not been reported in the Chinese psoriatic patients.

OBJECTIVE

The aim of this study was to verify the impacts of candidate genes polymorphisms on the effectiveness of MTX in a Chinese psoriatic population.

METHODS

In this study, we enrolled 259 psoriasis patients from two clinical centres. Each of them received MTX treatment at 7.5-15 mg/week for at least 8 weeks. Patients were stratified as responders and non-responders according to whether the Psoriasis Area and Severity Index score declined more than 75% (PASI75). According to previous reports, 16 single nucleotide polymorphisms (SNPs) were selected and genotyped for each patient using the Sequenom platform. Fisher's exact test, the chi-square test, Mann-Whitney tests and ANOVA analyses were used for statistical analysis.

RESULTS

Among 259 patients, there were 182 males and 77 females, 63 patients with psoriatic arthritis and 196 patients without arthritis phenotype, and the age of all patients ranged from 19 to 70 years (49.7 ± 13.6). The baseline PASI value of patients was 13.8 ± 8.5, and 33.2% of patients achieved a PASI75 response after MTX treatment. Patients carrying the ATP-binding cassette subfamily B member 1 gene (ABCB1) rs1045642 TT genotype were associated with more severe psoriasis skin lesion (P = 0.032). Furthermore, the ABCB1 rs1045642 TT genotype was found to be more frequent in non-responders (P = 0.017), especially in moderate-to-severe patients (P = 0.002) and patients without psoriatic arthritis (P = 0.026) after MTX treatment.

CONCLUSION

We have demonstrated for the first time that polymorphism of the ABCB1 rs1045642 TT genotype is predictive of a worse clinical response of skin lesions to MTX therapy in a Chinese psoriatic population.

Secreted stromal protein ISLR promotes intestinal regeneration by suppressing epithelial Hippo signaling

The Hippo-YAP signaling pathway plays an essential role in epithelial cells during intestinal regeneration and tumorigenesis. However, the molecular mechanism linking stromal signals to YAP-mediated intestinal regeneration and tumorigenesis is poorly defined. Here, we report a stroma-epithelium ISLR-YAP signaling axis essential for stromal cells to modulate epithelial cell growth during intestinal regeneration and tumorigenesis. Specifically, upon inflammation and in cancer, an oncogenic transcription factor ETS1 in stromal cells induces expression of a secreted protein ISLR that can inhibit Hippo signaling and activate YAP in epithelial cells. Deletion of Islr in stromal cells in mice markedly impaired intestinal regeneration and suppressed tumorigenesis in the colon. Moreover, the expression of stromal cell-specific ISLR and ETS1 significantly increased in inflamed mucosa of human IBD patients and in human colorectal adenocarcinoma, accounting for the epithelial YAP hyperactivation. Collectively, our findings provide new insights into the signaling crosstalk between stroma and epithelium during tissue regeneration and tumorigenesis.

Mucoadhesive-to-penetrating controllable peptosomes-in-microspheres co-loaded with anti-miR-31 oligonucleotide and Curcumin for targeted colorectal cancer therapy

Background: Accumulating evidences indicate that nanomedicines greatly decrease the side effects and enhance the efficacy of colorectal cancer (CRC) treatment. In particular, the use of rectal delivery of nanomedicines, with advantages such as fast therapeutic effects and a diminishing hepatic first-pass effect, is currently emerging. Method: We established a CRC targeted delivery system, in which α-lactalbumin peptosomes (PSs) co-loaded with a microRNA (miR)-31 inhibitor (miR-31i) and curcumin (Cur) were encapsuslated in thiolated TEMPO oxidized Konjac glucomannan (sOKGM) microspheres, referred as sOKGM-PS-miR-31i/Cur. The CRC targeting capability, drug release profiles, mucoadhesive-to-penetrating properties and therapeutic efficacy of sOKGM-PS-miR-31i/Cur delivery system were evaluated in colorectal cancer cells and azoxymethane-dextran sodium (AOM-DSS) induced tumor models. Results: sOKGM-PS-miR-31i/Cur delivery system were stable in the harsh gastrointestinal environment after rectal or oral administration; and were also mucoadhesive due to disulfide bond interactions with the colonic mucus layer, resulting in an enhanced drug retention and local bioavailability in the colon. Concomitantly, the released PS-miR-31i/Cur PSs from the microsphere was mucus-penetrating, efficiently passing through the colonic mucus layer, and allowed Cur and miR-31i specifically target to colon tumor cells with the guide of CD133 targeting peptides. Consequently, rectal delivery of sOKGM-PS-miR-31i/Cur microspheres suppressed tumor growth in an azoxymethane-dextran sodium sulfate (AOM-DSS)-induced tumor model. Conclusion: sOKGM-PS-miR-31i/Cur microspheres are effective rectal delivery system with combined advantages of mucoadhesive and mucus-penetrating properties, representing a potent and viable therapeutic approach for CRC.

MicroRNA-31 Reduces Inflammatory Signaling and Promotes Regeneration in Colon Epithelium, and Delivery of Mimics in Microspheres Reduces Colitis in Mice

BACKGROUND & AIMS

Levels of microRNA 31 (MIR31) are increased in intestinal tissues from patients with inflammatory bowel diseases and colitis-associated neoplasias. We investigated the effects of this microRNA on intestinal inflammation by studying mice with colitis.

METHODS

We obtained colon biopsy samples from 82 patients with ulcerative colitis (UC), 79 patients with Crohn's disease (CD), and 34 healthy individuals (controls) at Shanghai Tenth People's Hospital. MIR31- knockout mice and mice with conditional disruption of Mir31 specifically in the intestinal epithelium (MIR31 conditional knockouts) were given dextran sulfate sodium (DSS) or 2,4,6-trinitrobenzene sulfonic acid (TNBS) to induce colitis. We performed chromatin immunoprecipitation and luciferase assays to study proteins that regulate expression of MIR31, including STAT3 and p65, in LOVO colorectal cancer cells and organoids derived from mouse colon cells. Partially hydrolyzed alpha-lactalbumin was used to generate peptosome nanoparticles, and MIR31 mimics were loaded onto their surface using electrostatic adsorption. Peptosome-MIR31 mimic particles were encapsulated into oxidized konjac glucomannan (OKGM) microspheres, which were administered by enema into the large intestines of mice with DSS-induced colitis. Intestinal tissues were collected and analyzed by histology and immunohistochemistry.

RESULTS

Levels of MIR31 were increased in inflamed mucosa from patients with CD or UC, and from mice with colitis, compared with controls. STAT3 and nuclear factor-κB activated transcription of MIR31 in colorectal cancer cells and organoids in response to tumor necrosis factor and interleukin (IL)6. MIR31-knockout and conditional-knockout mice developed more severe colitis in response to DSS and TNBS, with increased immune responses, compared with control mice. MIR31 bound to 3' untranslated regions of Il17ra and Il7r messenger RNAs (RNAs) (which encode receptors for the inflammatory cytokines IL17 and IL7) and Il6st mRNA (which encodes GP130, a cytokine signaling protein). These mRNAs and proteins were greater in MIR31-knockout mice with colitis, compared with control mice; MIR31 and MIR31 mimics inhibited their expression. MIR31 also promoted epithelial regeneration by regulating the WNT and Hippo signaling pathways. OKGM peptosome-MIR31 mimic microspheres localized to colonic epithelial cells in mice with colitis; they reduced the inflammatory response, increased body weight and colon length, and promoted epithelial cell proliferation.

CONCLUSIONS

MIR31, increased in colon tissues from patients with CD or UC, reduces the inflammatory response in colon epithelium of mice by preventing expression of inflammatory cytokine receptors (Il7R and Il17RA) and signaling proteins (GP130). MIR31 also regulates the WNT and Hippo signaling pathways to promote epithelial regeneration following injury. OKGM peptosome-MIR31 microspheres localize to the colon epithelium of mice to reduce features of colitis. Transcript Profiling: GSE123556.

Interaction of water activity and temperature on the growth, gene expression and aflatoxin production by Aspergillus flavus on paddy and polished rice

Water activity (a_w) and temperature are two pivotal environmental factors affecting Aspergillus flavus growth and aflatoxin production. Here, we found that AFB₁ production on polished rice can occur over a wider range of temperature × a_w levels than that on paddies. For fungal growth on polished rice, the optimum conditions were a_w 0.92-0.96 and 28-37 °C. The maximum amounts of AFB₁ on polished rice was observed at 33 °C and a_w 0.96. Compared to 33 °C, all tested genes of A. flavus on polished rice were significantly up-regulated at 25 °C under a_w 0.96. The late structural genes of pathway were significantly down-regulated at 37 °C under a_w 0.96, although aflR and aflS and most of early structural genes were up-regulated. Compared to a_w 0.96, most of pathway genes were significantly down-regulated at a_w 0.90 and 0.99 under 33 °C, although two regulatory genes were up-regulated at a_w 0.90.

Tracing the sources of nitrate in the rivers and lakes of the southern areas of the Tibetan Plateau using dual nitrate isotopes

Based on a quantitative analysis of nitrate concentrations, the nitrate sources and temporal variability of the rivers, lakes, and wetlands of Tibet were assessed for the first time using dual isotope technology. Water samples were collected once in July 2017 for analysis of nitrate concentration and isotopic composition. The overall values of δ¹⁵N-NO₃^- and δ¹⁸O-NO₃^- ranged from +1.8‰ to +23.0‰, and from -6.3‰ to +22.2‰ respectively. Duel isotopic composition suggested that nitrification of soil organic nitrogen was the main source of nitrate in the Yalu Tsangpo River. Furthermore, anthropogenic nitrogen inputs become more important in downstream than upstream because of intensive agricultural activities and urban input. In the rivers of the Ngari District, nitrate is mainly derived from desert deposits, manure and sewage, and chemical fertilisers. Different rivers show different characteristics of nitrate sources depending on the location, topography, landform, and climate of the river basins. Animal manure, nitrification of soil organic matter, and desert deposits are mainly responsible for the shifting of nitrate isotopic signatures in lakes, which are minimally affected by human activities. In wetlands, biological nitrification and denitrification could be the main processes of nitrogen migration and transformation. These results provide useful information in revealing the fate of nitrate in different aquatic ecosystems and different areas of Tibet.

Improvements in epidermal function prevent relapse of psoriasis: a self-controlled study

While therapeutic approaches for psoriasis are widely available, preventive regimens are lacking. We aimed to determine whether improvements in epidermal function could prevent psoriasis relapse. Two self-controlled cohort studies were designed, enrolling two cohorts of patients with psoriasis (n = 30 and n = 60) to be treated topically with an in-house-prepared emollient or ATOPALM^® cream applied twice daily to one forearm for 20 and 30 days, respectively, while the same sites on the contralateral arm served as the untreated control. Epidermal function on both arms was assessed prior to and at the end of the trials. Delayed relapse on the treated arm was seen in 54.5% and 71% of patients in the first and second cohort, respectively. The time of psoriatic relapse correlated with the extent of abnormalities in baseline epidermal function. These results suggest that improvements in epidermal function with topical emollients can prevent/attenuate the development of psoriasis.

[High mobility group box 1 promotes apoptosis of astrocytes after oxygen glucose deprivation/reoxygenation by regulating the expression of Bcl-2 and Bax]

OBJECTIVE

To investigate the effect of high mobility group protein box 1 (HMGB1) on apoptosis of astrocytes after oxygen glucose deprivation/reoxygenation (OGD/R), and to investigate the possible mechanism by evaluating the expression of apoptosis related protein Bcl-2 and Bax.

METHODS

The cerebral cortex astrocytes of neonatal rats were divided into normal group, model group, interference group and control group. Lentivirus vector of rat HMGB1 short hairpin RNA (shRNA) was used to suppress the HMGB1 protein expression in the astrocytes. Then the detection was made after astrocytes were deprived of oxygen and glucose 6 h, reoxygenation for 24 h. The effect of RNA interference was evaluated by Western blotting. The cell survival rate was measured by MTT assay. The apoptosis of astrocytes was determined by TUNEL assay. The expressions of Bcl-2 and Bax were detected by Western blotting.

RESULTS

Compared with the normal group, the protein expression of HMGB1 was significantly increased in model group after OGD/R (P<0.001), the astrocytes survival rate was decreased (P<0.001), the number of apoptotic cells labeled with TUNEL was increased (P<0.001), and the ratio of Bcl-2/Bax was decreased (P<0.001). Compared with the model group, RNA interference effectively inhibited the expression of HMGB1 in interference group (P<0.001), the astrocytes survival rate was increased (P<0.001), the number of apoptotic cells labeled with TUNEL was reduced (P<0.01), and the ratio of Bcl-2/Bax was increased (P<0.001).

CONCLUSION

The apoptosis of astrocytes can be induced by HMGB1 after OGD/R, and the mechanism may be related to regulating the expression of apoptosis related proteins Bcl-2 and Bax.

Inhibiting High Mobility Group Box-1 Reduces Early Spinal Cord Edema and Attenuates Astrocyte Activation and Aquaporin-4 Expression after Spinal Cord Injury in Rats

High mobility group box-1 (HMGB1) could function as an early trigger for pro-inflammatory activation after spinal cord injury (SCI). Spinal cord edema contributes to inflammatory response mechanisms and a poor clinical prognosis after SCI, for which efficient therapies targeting the specific molecules involved remain limited. This study was designed to evaluate the roles of HMGB1 on the regulation of early spinal cord edema, astrocyte activation, and aquaporin-4 (AQP4) expression in a rat SCI model. Adult female Sprague-Dawley rats underwent laminectomy at T10, and the SCI model was induced by a heavy falling object. After SCI, rats received ethyl pyruvate (EP) or glycyrrhizin (GL) via an intraperitoneal injection to inhibit HMGB1. The effects of HMGB1 inhibition on the early spinal cord edema, astrocyte activation (glial fibrillary acidic protein [GFAP] expression), and AQP4 expression after SCI (12 h-3 days) were analyzed. The results showed that EP or GL effectively inhibited HMGB1 expression in the spinal cord and HMGB1 levels in the serum of SCI rats. HMGB1 inhibition improved motor function, reduced spinal cord water content, and attenuated spinal cord edema in SCI rats. HMGB1 inhibition decreased SCI-associated GFAP and AQP4 overexpression in the spinal cord. Further, HMGB1 inhibition also repressed the activation of the toll-like receptor 4/myeloid differentiation primary response gene 88/nuclear factor-kappa B signaling pathway. These results implicate that HMGB1 inhibition improved locomotor function and reduced early spinal cord edema, which was associated with a downregulation of astrocyte activation (GFAP expression) and AQP4 expression in SCI rats.