Outcomes and phenotypic expression of rare variants in hypertrophic cardiomyopathy genes in over 200,000 adults

Background

Hypertrophic cardiomyopathy (HCM) is caused by rare variants in sarcomere-encoding genes, but little is known about the clinical significance of these variants in the general population.

Purpose

To determine the population prevalence of HCM-associated sarcomeric variants, characterise their phenotypic manifestations, estimate penetrance, and identify associations between sarcomeric variants and clinical outcomes, we performed an observational study of 218,813 adults in the UK Biobank (UKBB), of whom 200,584 have whole exome sequencing (WES).

Methods

We carried out an integrated analysis of WES and cardiac magnetic resonance (CMR) imaging in UK Biobank participants stratified by sarcomere-encoding variant status. Computer vision techniques were used to automatically segment the four chambers of the heart (Figure 1). Cardiac motion analysis was used to derive strain and strain rates. Regional analysis of left ventricular wall thickness was performed using three-dimensional modelling of these segmentations.

Results

Median age at recruitment was 58 (IQR 50–63 years), and participants were followed up for a median of 10.8 years (IQR 9.9–11.6 years) with a total of 19,507 primary clinical events reported.

The prevalence of rare variants (allele frequency <0.ehab724.17314) in HCM-associated sarcomere-encoding genes in 200,584 participants was 2.9% (n=5,727; 1 in 35), and the prevalence of pathogenic or likely pathogenic variants (SARC-P/LP) was 0.24% (n=474, 1 in 423).

SARC-P/LP variants were associated with increased risk of death or major adverse cardiac events (MACE) compared to controls (HR 1.68, 95% CI 1.37–2.06, p<0.001), mainly due to heart failure endpoints (Figure 2: cumulative hazard curves with zoomed plots for lifetime risk of A) death and MACE or B) heart failure, stratified by genotype; genotype negative (SARC-NEG), carriers of indeterminate sarcomeric variants (SARC-IND) or SARC-P/LP; C) Forest plot of comparative lifetime risk of clinical endpoints by genotype).

While males had a higher overall risk of adverse outcomes, the incremental genetic risk from SARC-P/LP mutations was greater in females (HR for females: 2.18 CI 1.65–2.89, p<0.001; HR for males: 1.42 CI 1.05–1.9, p=0.02).

In 21,322 participants with CMR, SARC-P/LP were associated with asymmetric increase in left ventricular maximum wall thickness (10.9±2.7 vs 9.4±1.6 mm, p<0.001) but hypertrophy (≥13mm) was only present in 16% (n=7/43, 95% CI 7–31%). Other rare sarcomere-encoding variants had a weak effect on wall thickness (9.5±1.7 vs 9.4±1.6 mm, p=0.002) with no combined excess cardiovascular risk.

Conclusions

In the general population, SARC-P/LP variants have low aggregate penetrance for overt HCM but are associated with increased risk of adverse cardiovascular outcomes and a sub-clinical cardiomyopathic phenotype. Although absolute event rates are low, identification of these variants may enhance risk stratification beyond familial disease.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The study was supported by the Medical Research Council, UK (MC-A651-53301); National Institute for Health Research (NIHR) Imperial College Biomedical Research Centre; NIHR Royal Brompton Cardiovascular Biomedical Research Unit; British Heart Foundation (NH/17/1/32725, RG/19/6/34387, RE/18/4/34215).

Deep learning for automatic calcium scoring in population based cardiovascular screening

Background

High volumes of standardized coronary artery calcium (CAC) scans are generated in screening that need to be scored accurately and efficiently to risk stratify individuals.

Purpose

To evaluate the performance of deep learning based software for automatic coronary calcium scoring in a screening setting.

Methods

Participants from the Robinsca trial that underwent low-dose ECG-triggered cardiac CT for calcium scoring were included. CAC was measured with fully automated deep learning prototype and compared to the original manual assessment of the Robinsca trial. Detection rate, positive Agatston score and risk categorization (0–99, 100–399, ≥400) were compared using McNemar test, ICC, and Cohen's kappa. False negative (FN), false positive (FP) rate and diagnostic accuracy were determined for preventive treatment initiation (cut-off ≥100 AU).

Results

In total, 997 participants were included between December 2015 and June 2016. Median age was 61.0 y (IQR: 11.0) and 54.4% was male. A high agreement for detection was found between deep learning based and manual scoring, κ=0.87 (95% CI 0.85–0.89). Median Agatston score was 58.4 (IQR: 12.3–200.2) and 61.2 (IQR: 13.9–212.9) for deep learning based and manual assessment respectively, ICC was 0.958 (95% CI 0.951–0.964). Reclassification rate was 2.0%, with a very high agreement with κ=0.960 (95% CI: 0.943–0.997), p<0.001. FN rate was 0.7% and FP rate was 0.1% and diagnostic accuracy was 99.2% for initiation of preventive treatment.

Conclusion

Deep learning based software for automatic CAC scoring can be used in a cardiovascular CT screening setting with high accuracy for risk categorization and initiation of preventive treatment.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Robinsca trial was supported by advanced grant of European Research Council

[Effects of ambient particulate matter (PM10) on prevalence of diabetes and fasting plasma glucose]

Objective: To explore the effect of long-term exposure to ambient particulate matter (PM₁₀) on the prevalence of diabetes and fasting plasma glucose (FPG). Methods: The subjects of the study were from the baseline population of "Jinchang Cohort", and 24 285 subjects were finally included after excluding incomplete home address information and diabetic diagnosis information. The demographic characteristics, lifestyle and health status of the survey subjects were collected through questionnaire, physical examination and laboratory tests. ArcGIS software was used to match the nearest environmental monitoring stations for each subject according to residential address. Two-year average concentrations of PM₁₀ were calculated to estimate exposure level. The logistic regression and the multiple linear regression were conducted to assess the effects of ambient PM₁₀ on the prevalence of diabetes and FPG. The restricted cubic spline was used to quantify the dose-response relationship. Stratified analysis and effect modification analysis were also performed. Results: The age of 24 285 participants was (49.32±8.60) years, and the BMI was (24.22±6.09) kg/m². There were 13 950 (57.44%) males and 2 066 (8.51%) diabetic patients. After adjusting for confounders, for every 10 μg/m³ increase in the average PM₁₀ concentration in the first two years of the survey, the prevalence of diabetes increased [OR (95%CI) =1.05 (1.01-1.09)]and the FPG level elevated [β (95%CI) = 0.061 (0.047-0.076) mmol/L]. The results of the restricted cubic spline analysis showed a nonlinear relationship between PM₁₀ concentration and FPG level (P<0.001). Further subgroup analysis showed that female [OR (95%CI) =1.10 (1.03-1.18)], people over 50 years old [OR (95%CI) =1.06 (1.02-1.11) ], subjects with family history of diabetes [OR (95%CI) = 1.13 (1.04-1.23) ], and with hypertension [OR (95%CI) = 1.07 (1.02-1.12) ] had a stronger association between the prevalence of diabetes and PM₁₀ exposure (all P interaction values were<0.05). The effects of PM₁₀ on FPG were more significant in people older than 50 years[β (95%CI) = 0.080 (0.050-0.109) mmol/L], with family history of diabetes [β (95%CI) = 0.087 (0.036-0.137) mmol/L], and hypertension [β (95%CI) = 0.077 (0.046-0.108) mmol/L] (all P interaction values were<0.05). Conclusions: Long-term exposure to ambient PM₁₀ increases the diabetes prevalence and FPG. People older than 50 years old, with family history of diabetes and hypertension could be more sensitive to the effects of PM₁₀ exposure.

Hydrogen sulfide and nitric oxide are involved in melatonin-induced salt tolerance in cucumber

Hydrogen sulfide (H₂S) is a novel gaseous signaling molecule in response to adversity stress. Melatonin (MT) is a multifunctional molecule that plays an important role in regulating plant stress resistance. However, the interactions between H₂S and MT are still unknown. Therefore, the role of H₂S in MT-induced salt tolerance was elucidated in this study by measuring the antioxidant defense system and photosynthetic characteristics of cucumber. In addition, the crosstalk among H₂S, NO, and mitogen-activated protein kinase (MAPK) was investigated. Results showed that MT induced the production of H₂S by significantly increasing the activity of L-/D-cysteine desulfhydrase, thereby regulating photosynthetic efficiency, antioxidant enzyme activity, and antioxidant enzyme gene expression in cucumber, thus alleviating reactive oxygen species burst by salt stress. In this process, the H₂S and NO induced by MT were inhibited by NO scavenger (cPTIO) and H₂S scavenger (HT) but not affected by MAPK inhibitor (U0126). Intriguingly, the expression of MAPK3/4/6/9 was inhibited by HT and cPTIO. These results suggested that H₂S may act as downstream of MT, interact with NO and MAPK cascades, and jointly participate in the process of MT mitigating salt stress in cucumber. In addition, H₂S and NO are upstream signaling molecules of the MAPK cascades.

CircRNA Circ-CCND1 Aggravates Hepatocellular Carcinoma Tumorigenesis by Regulating the miR-497-5p/HMGA2 Axis

Circular RNAs (circRNAs) are key regulators in hepatocellular carcinoma (HCC) tumorigenesis and development, yet it is unclear whether circ-CCND1 participates in regulating HCC progression. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for detecting the expressions of circ-CCND1, microRNA (miR) -497-5p, and high mobility group AT-hook 2 (HMGA2) mRNA in HCC tissues and cell lines. Subcellular fractionation assay was used to analyze the localization of circ-CCND1 in HCC cell lines. Loss-of-function experiments were conducted to examine the effects of circ-CCND1 on HCC cell proliferation, migration, and invasion. Dual-luciferase reporter gene assay was employed for detecting the targeting relationships of circ-CCND1 and miR-497-5p, as well as miR-497-5p and HMGA2, respectively. Western blot was used to detect the regulatory functions of circ-CCND1 and miR-497-5p on HMGA1 expression at protein level. Circ-CCND1 and HMGA2 expressions in HCC were significantly up-regulated and miR-497-5p expression was markedly decreased. High circ-CCND1 expression was associated with relatively large tumor size and lymph node metastasis in HCC patients. In addition, circ-CCND1 was mainly distributed in the cytoplasm of HCC cells. Functionally, knockdown of circ-CCND1 remarkably suppressed HCC cell proliferation, migration, and invasion. Mechanistically, miR-497-5p was a direct target of circ-CCND1 and miR-497-5p specifically modulated HMGA2 expression. Furthermore, miR-497-5p inhibitors and or HMGA2 overexpression partially counteracted the suppressing effect induced by si-circ-CCND1 on the malignant phenotype of HCC cells. Circ-CCND1 plays a cancer-promoting role in HCC by modulating the miR-497-5p/HMGA2 axis. Therefore, targeting circ-CCND1 is likely to be a promising therapeutic strategy for HCC.

Sympathetic activity is correlated with satellite cell aging and myogenesis via β2-adrenoceptor

Background and objective

Sympathetic activity plays an important role in the proliferation and differentiation of stem cells, and it changes over time, thereby exerting differential effects on various stem cell types. Aging causes sympathetic hyperactivity in aged tissues and blunts sympathetic nerves regulation, and sympathetic abnormalities play a role in aging-related diseases. Currently, the effect of sympathetic activity on skeletal muscle stem cells, namely satellite cells (SCs), is unclear. This study aimed to investigate the effects of skeletal muscle sympathetic activity on SC aging and skeletal muscle repair.

Materials and methods

To evaluate skeletal muscle and fibrotic areas, numbers of SCs and myonuclei per muscle fiber, β2-adrenoceptor (β2-ADR) expression, muscle repair, and sympathetic innervation in skeletal muscle, aged mice, young mice that underwent chemical sympathectomy (CS) were utilized. Mice with a tibialis anterior muscle injury were treated by barium chloride (BaCl₂) and clenbuterol (CLB) in vivo. SCs or C2C12 cells were differentiated into myotubes and treated with or without CLB. Immunofluorescence, western blot, sirius red, and hematoxylin–eosin were used to evaluate SCs, myogenic repair and differentiation.

Results

The number of SCs, sympathetic activity, and reparability of muscle injury in aged mice were significantly decreased, compared with those in young mice. The above characteristics of young mice that underwent CS were similar to those of aged mice. While CLB promoted the repair of muscle injury in aged and CS mice and ameliorated the reduction in the SC number and sympathetic activity, the effects of CLB on the SCs and sympathetic nerves in young mice were not significant. CLB inhibited the myogenic differentiation of C2C12 cells in vitro. We further found that NF-κB and ERK1/2 signaling pathways were activated during myogenic differentiation, and this process could be inhibited by CLB.

Conclusion

Normal sympathetic activity promoted the stemness of SCs to thereby maintain a steady state. It also could maintain total and self-renewing number of SCs and maintain a quiescent state, which was correlated with skeletal SCs via β2-ADR. Normal sympathetic activity was also beneficial for the myogenic repair of injured skeletal muscle.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02571-8.

Suppression of MD2 inhibits breast cancer in vitro and in vivo

PURPOSE

To explore the effects of the intervening measure targeting myeloid differentiation 2 (MD2) on breast cancer progression in vitro and in vivo.

METHODS

The expression of MD2 in normal breast cells (Hs 578Bst) and three kinds of breast carcinoma cell lines (MCF-7, MDA-MB-231 s and 4T1) were detected by western blot. MTT assay was used to detect the proliferation of 4T1 cells treated by L6H21, cell migration and invasion was measured by wound healing assay and trans-well matrigel invasion assay, respectively. In addition, to further study the role of MD2 in tumor progression, we assessed the effects of inhibition of MD2 on the progression of xenograft tumors in vivo.

RESULTS

The expression of MD2 is much higher in MDA-MB-231 s and 4T1cells than that in normal breast cells (Hs 578Bst) or MCF-7 cells (p < 0.05). In vitro, suppression of MD2 by L6H21 has a significant inhibition of proliferation, migration and invasion in 4T1 cells in dose-dependent manner. In vivo, L6H21 pretreatment significantly improved survival of 4T1-bearing mice (p < 0.05). Additionally, we also observed that none of the mice died from the toxic effect of 10 mg kg-1 L6H21 in 60 days.

CONCLUSION

Overall, this work indicates that suppression of MD2 shows progression inhibition in vitro and significantly prolong survival in vivo. These findings provide the potential experimental evidence for using MD2 as a therapeutic target of breast carcinoma.

PLDα1 and GPA1 are involved in the stomatal closure induced by Oridonin in Arabidopsis thaliana

Oridonin is an important diterpenoid, which plays an important role in plant growth and development. PLDα1 and GPA1 are involved in many biotic or abiotic stresses. In this study, using the seedlings of Arabidopsis thaliana L. wild type (WT), PLDα1 defective mutant (pldα1), GPA1 defective mutant (gpa1) and pldα1/gpa1 double mutant as materials, the effect of stomatal apertures responding to Oridonin and the functions of PLDα1 and GPA1 in this response were investigated. The results showed that 60 μmol·L-1 of Oridonin induced stomatal closure and significantly increased the relative expression levels of GPA1 and PLDα1. Oridonin increased H2O2 accumulation in guard cells by inhibiting the antioxidant enzymes. The increase of H2O2 caused the expression of OST1, which is a positive regulatory gene for stomatal closure. Both PLDα1 and GPA1 were involved in Oridonin-induced stomatal closure and PLDα1 acted downstream of GPA1. The results suggested that Oridonin caused stomatal closure by affecting GPA1 and promoting PLDα1 to produce PA, and further accumulating H2O2 to upregulate gene OST1.

[Screening and analysis of Treponema pallidum specific antibody among childbearing age people in rural areas of Yunnan province, 2013-2017]

Objective: To determine the prevalence, epidemiological characteristics, and related factors of syphilis infection among rural childbearing age people to promote medical interventions on pre-pregnancy aristogenesis and syphilis infection in Yunnan province. Methods: The subjects in this study were 18-49-year-old rural couples of childbearing age from the National Free Preconception Health Examination Project in Yunnan province during 2013-2017. The descriptive study was carried out to determine the positive rate of Treponema pallidum specific antibody (TPsAb) and related sociodemographic characteristics. Results: The overall positive rate of TPsAb was 0.38% (8 204/2 160 455) in 2 160 455 rural childbearing age people in Yunnan. The positive rate of TPsAb was 0.39% (4 019/1 040 981) in men,higher than that in women (0.37%,4 185/1 119 474). The positive rate of TPsAb was highest in the age group 45-49 years (0.70%,158/22 511). The positive rate of TP antibody in the minority ethnic groups and Han ethnic groups appeared the same (0.38%). However,the highest positive rate of TPsAb was 0.77% (461/60 153) in Hani ethnic group among all the 17 minority ethnic groups. People with education level of primary education had the highest anti-TP positive rate (0.54%,2 327/431 275). The positive rate of TPsAb appeared the highest in Zhaotong (0.73%, 2 049/281 614) area among all the 16 prefectures of the province. The positive rate of TPsAb in the population from the impoverished regions (0.50%,2 963/590 039) was higher than in other disadvantaged areas (0.34%, 3 115/929 368) or areas with average income (0.33%,2 126/641 048). Significant differences appeared in the positive rate of TPsAb among populations of different ages, ethnic, education level, and economic level groups (trend χ² test, P<0.001). Conclusions: The positive rate of TP antibody in rural childbearing age people in Yunnan was related to multi factors,including sex,age,ethnic group,education level,area, residence, and local economic situation. The positive rate of TPsAb was higher in men than in women. And people with elder age, lower education level, being Hani or Lahu ethnic group, and Zhaotong areas had higher TPsAb positive rates and higher syphilis infection risk.

POS0081 CLINICAL FEATURES OF PEDIATRIC BEHÇET’S DISEASE IN CHINA

Background:

Behçet’s disease (BD) is a systemic inflammatory disease involving primarily the oral and genital mucosa, skin and eyes. Some patients exhibit broader involvement with multi-organ system inflammation, causing significant morbidity and mortality. With much of the literature focused on adult-onset BD, the clinical spectrum of BD in children is not well studied. The diagnosis of pediatric BD is difficult to make due to its rarity in childhood, the paucity of experience among pediatricians and the lack of validated diagnostic criteria.

Objectives:

We aim to describe the clinical characteristic of children with Behçet’s disease in China.

Methods:

We performed a cross-sectional cohort analysis of patients with BD recruited between June 2017 and May 2020. We enrolled a total of 848 patients with pediatric BD (onset prior to age 18 years) and 1531 patients with adult-onset BD. Clinical data were collected by retrospective chart review.

Results:

From a cohort of 848 patients with pediatric BD (412 males, 436 females), the average age of disease onset was 11.59 ± 4.11 years and the earliest case was appeared the first symptom at 7 months of age. Clinical manifestations in this group included recurrent oral aphtosis (100%), genital ulcers (77.71%), ocular involvement (30.19%), skin involvement (63.56%), neurological involvement (4.60%), gastrointestinal involvement (20.05%), vascular involvement (9.79%), heart valve involvement (3.66%), arthritis / arthralgia (32.43%), fever (0.35%) and positive pathergy test (21.11%; Table 1). The prevalence of these clinical findings was largely similar to that of adult BD patients with the exception of mild differences in the frequency of gastrointestinal, heart valve, joint involvement and fever. However, the time from symptom onset to diagnosis was significantly longer in children with BD compared to adults (13.34±9.13 years vs. 6.73±33.21 years, P<0.001). The most common initial symptom in pediatric BD was recurrent oral aphtosis (91.57% vs. 86.28% in adults, P<0.001).

In the pediatric group, clinical manifestations also differed between males and females. In addition to oral ulcers, the most common clinical manifestations in male patients were ocular involvement (42.23%), vascular involvement (15.53%), heart valve involvement (5.10%) and epididymitis (9.95%). Among female patients, the frequency of genital ulcers is significantly higher than that of men (86.24% vs. 68.69%, P<0.001).

Conclusion:

We described the clinical characteristics of a large cohort of pediatric BD patients in China. While the clinical manifestations are largely similar to adult BD, the time from symptom onset to diagnosis is significantly delayed in pediatric patients. Our study highlights the need to improve awareness of BD among pediatric providers to facilitate rapid diagnosis and treatment in children.

References:

[1]Yildiz et al. Pediatric Behçet’s disease- clinical aspects and current concepts. Eur J Rheumatol 2020; 7(Suppl 1): S38-S47.

[2]Koné-Paut. Behçet’s disease in children, an overview. Pediatric Rheumatology (2016) 14:10.

Table 1.

Comparison of clinical features of BD in children and adults

Children(n=848)Adult(n=1531)PAge of first symptom (y)11.59±4.1127.08±7.91Sex(M/F)412/436Years of diagnosis (y)13.34±9.136.73±33.21<0.001Recurrent oral aphthosis848 (100%)1518 (99.15%)0.007Genital Ulcers659 (77.71%)1891152 (75.24%)3790.176Ocular signs256 (30.19%)592508 (33.18%)10230.134Cutaneous signs539 (63.56%)3091020 (66.62%)5110.132Neurological signs39 (4.60%)80982 (5.36%)14490.421Gastrointestinal signs170 (20.05%)678244 (15.94%)13870.001Vascular signs83 (9.79%)765162 (10.58%)13690.542Heart valve signs31 (3.66%)817110 (7.18%)1421<0.001Joint signs275 (32.43%)573612 (39.97%)919<0.001Fever3 (0.35%)84522 (1.44%)15090.013Positive pathergy test179 (21.11%)669347 (22.66%)11840.381

Acknowledgements:

China Behcet’ Disease Patients Assossiation.

Disclosure of Interests:

None declared.

POS0833 A RETROSPECTIVE COHORT STUDY IN CHINESE PATIENTS WITH ADULT POLYMYOSITIS AND DERMATOMYOSITIS: RISK OF COMORBIDITIES AND SUBCLASSIFICATION USING MACHINE LEARNING

Background:

Idiopathic inflammatory myopathy (IIM), also known as myositis, refers to a group of heterogeneous disorders including polymyositis (PM), dermatomyositis (DM), inclusion body myositis and immune-mediated necrotising myopathy. Phenotype, pathogenesis, and prognosis vary due to multi-organ involvement and comorbidities. With the clinical application of MSAs, a new classification system for myositis was explored to reduce confusion between subgroups. But it is far from showing the full picture of myositis due to high heterogeneity. Therefore, it is necessary to systematically evaluate the relevant risk factors of myositis for ILD, other rheumatic diseases, and malignancy for better clinical vigilance. And further exploring the subclassification of myositis is critical.

Objectives:

To identify the risk factors in Chinese patients with adult polymyositis and dermatomyositis for their comorbidities and explore a subclassification system.

Methods:

Clinical records of 397 patients with idiopathic inflammatory myopathies were retrospectively reviewed. Logistic regression was used to identify potential risk factors for interstitial lung disease (ILD), other rheumatic diseases, and malignancy after bivariate analysis. Hierarchical clustering and decisional tree were utilized to identify subgroups and explore a subclassification system.

Results:

A total of 119 polymyositis and 191 dermatomyositis patients were included. Anti-PM/Scl, anti-Ro52, anti-aminoacyl-tRNA synthetase and anti-MDA5 (adjusted odds ratios (AOR)=4.779, 1.917, 5.092 and 7.714 respectively) antibodies were risks (p<0.05), whereas overlapping malignancy was protective (AOR=0.107; p=0.002) for ILD across polymyositis, dermatomyositis and the total group. In subgroup models, Raynaud’s phenomenon, arthralgia and semi-quantitative anti-nuclear antibody (AOR=51.233, 4.261, 3.047 respectively) were risks for other overlapping rheumatic diseases (p<0.05). For overlapping malignancy, male and anti-TIF1γ antibodies (AOR=2.533, 16.949) were risks (p<0.05), whereas disease duration and combination of ILD (AOR=0.954, 0.106) were protective in the total group (p<0.05); while anti-NXP2 antibodies were identified as risk factors (AOR=73.152; p=0.038) in polymyositis. Hierarchical clustering suggested a subclassification with 6 subgroups: malignancy overlapping dermatomyositis, classical dermatomyositis, polymyositis with severe muscle involvement, dermatomyositis with ILD, polymyositis with ILD, and overlapping of myositis with other rheumatic diseases according to the characteristics of grouped patients. Accuracy of the classification and regression trees model was 0.768 (95% CI 0.711 to 0.819) on training set and 0.633 (95%CI 0.499 to 0.754) on test set.

Conclusion:

Accompanying ILD, other rheumatic diseases and malignancy are strongly associated with clinical manifestation and myositis-specific or myositis-associated autoantibodies among Chinese polymyositis and dermatomyositis patients. The subclassification system proposed a more precise phenotype defining toward stratified treatments.

Acknowledgements:

The study was supported by the Natural Science Foundation of China [No. 81803932] and the Natural Science Foundation of Guangdong Province [No. 2018030310025 and 2017A030313868]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Disclosure of Interests:

None declared

AP2-microRNA-26a overexpression reduces visceral fat mass and blood lipids

BACKGROUND

MicroRNA-26a (miR-26a) is a key player in tumor suppression and plays important roles in glucose and lipid metabolism. However, its function in adipose tissue is not well defined.

OBJECTIVE

The study aimed to examine the effect on fat expansion and function of miR-26a in adipose tissue.

METHODS

Adipose-specific miR-26a transgenic mice (Ap2-miR-26a) were firstly generated by breeding miR-26a floxed (Mir26a^loxP/^loxP) mice with Ap2-Cre recombinase transgenic mice. The effects of miR-26a adipose-specific overexpression on body weight, body fat composition, fat pad weight, adipocyte size, blood lipid levels, glucose metabolism, and adipogenesis were investigated in mice on a chow diet and a high fat diet. White adipose tissue browning was evaluated by energy expenditure, adipocyte morphology and browning related genes expression levels both at room temperature and after cold exposure. Gene expression was determined by Real-Time quantitative PCR and western blotting.

RESULTS

MiR-26a was specifically overexpressed in adipose by ~4 folds. Ap2-miR-26a mice had a moderate decrease in body weight, body fat composition, epididymal white adipose (eWAT) weight and blood lipid levels, along with smaller adipocytes in eWAT. The favorable phenotype was not due to white adipose tissue browning (even after cold exposure) or adipogenesis or lipolysis. Ap2-miR-26a mice exhibited no significant metabolic phenotype under high-fat-diet feeding.

CONCLUSION

This study suggests that adipose-specific overexpression of miR-26a could moderately reduce visceral fat pad mass and lipid levels independent of white adipose tissue browning, adipogenesis and adipose lipolysis based on the gene expression level.

GDC-0326 Enhances the Effects of 5-Fu in Colorectal Cancer Cells by Inducing Necroptotic Death

AIM

Chemoresistance to 5-fluorouracil (5-Fu) is common in colorectal cancer (CRC). Programmed necrosis (necroptosis) is an alternative form of programmed cell death regulated by receptor-interacting protein kinase (RIPK) 1 and 3, assumed as a novel target of cancer therapy. In this study, we aimed to explore whether a novel small molecular agent GDC-0326 could facilitate the effect of 5-Fu through necroptosis.

MAIN METHODS

Cell Counting Kit-8 (CCK-8) assay and colony formation were performed to confirm the function of GDC-0326 in CRC cells. Western blot and immunofluorescence were conducted to measure the altered expressions of RIPK1/RIPK3 induced by GDC-0326. Subcutaneous tumor models were used to evaluate the chemotherapeutic effects and concomitant side effects of GDC-0326 in vivo.

KEY FINDINGS

We found that GDC-0326 effectively suppressed the growth of CRC cells in a dose-dependent manner. The induction of necroptosis by GDC-0326 was correlated with the modulation of RIPK1 and RIPK3. Necrostatin-1 and GSK-872, inhibitors of RIPK1 and RIPK3, respectively, could rescue the cell death induced by GDC-0326. In addition, in vitro and in vivo studies showed that 5-Fu plus GDC-0326 evinced a better antitumor efficacy by suppressing tumor growth and increasing tumor necrosis with no increased toxicity.

SIGNIFICANCE

This study demonstrates that GDC-0326 plus 5-Fu has augmented antitumor efficacy and acceptable safety, which might be a promising therapeutic strategy for CRC patients in the future.

The cross-sectional and longitudinal associations of dietary patterns with knee symptoms and MRI detected structure in patients with knee osteoarthritis

OBJECTIVES

To examine the cross-sectional and longitudinal associations of dietary patterns with knee symptoms and structures in patients with knee osteoarthritis (OA).

METHODS

Participants with symptomatic knee OA were recruited from a randomised, placebo-controlled trial conducted in Tasmania (N = 259) and Victoria (N = 133). Diet was assessed by the Anti-Cancer Council of Victoria food frequency questionnaire. Factor analysis was used to identify dietary patterns. Knee symptoms were assessed using Western Ontario and McMaster Universities Arthritis Index (WOMAC) and structures using MRI. Multivariable linear regressions were used to examine associations.

RESULTS

Three dietary patterns ("high-fat", "healthy" and "mixed") were identified in whole sample. Participants with higher "healthy pattern" score had lower total WOMAC, pain, function and stiffness scores at baseline but the associations were not significant over 24 months. Three ("western", "vegetable and meat" and "mediterranean") and two ("processed" and "vegetable") patterns were identified in Tasmania and Victoria, respectively. Cross-sectionally, only "mediterranean pattern" and "vegetable pattern" scores were significantly and negatively associated with total WOMAC or function scores. Longitudinally, participants with higher "western pattern" had worsening function (β: 0.35, 95%CI: 0.03, 0.67) and total WOMAC (β: 0.40, 95%CI: 0.07, 0.72) scores; furthermore, "vegetable pattern" was associated with decreased WOMAC stiffness score (β: -0.47, 95%CI: -0.93, -0.02). In contrast, dietary patterns were largely not associated with structural changes.

CONCLUSION

Some healthy dietary patterns were associated with reduced joint symptoms but dietary patterns were not associated with joint structure in this sample with knee OA. Further studies are required to confirm these findings.

Identification of the angiogenesis related genes for predicting prognosis of patients with gastric cancer

INTRODUCTION

Angiogenesis is a key factor in promoting tumor growth, invasion and metastasis. In this study we aimed to investigate the prognostic value of angiogenesis-related genes (ARGs) in gastric cancer (GC).

METHODS

mRNA sequencing data with clinical information of GC were downloaded from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. The differentially expressed ARGs between normal and tumor tissues were analyzed by limma package, and then prognosis‑associated genes were screened using Cox regression analysis. Nine angiogenesis genes were identified as crucially related to the overall survival (OS) of patients through least absolute shrinkage and selection operator (LASSO) regression. The prognostic model and corresponding nomograms were establish based on 9 ARGs and verified in in both TCGA and GEO GC cohorts respectively.

RESULTS

Eighty-five differentially expressed ARGs and their enriched pathways were confirmed. Significant enrichment analysis revealed that ARGs-related signaling pathway genes were highly related to tumor angiogenesis development. Kaplan-Meier analysis revealed that patients in the high-risk group had worse OS rates compared with the low-risk group in training cohort and validation cohort. In addition, RS had a good prognostic effect on GC patients with different clinical features, especially those with advanced GC. Besides, the calibration curves verified fine concordance between the nomogram prediction model and actual observation.

CONCLUSIONS

We developed a nine gene signature related to the angiogenesis that can predict overall survival for GC. It's assumed to be a valuable prognosis model with high efficiency, providing new perspectives in targeted therapy.

"Sweet tooth"-oriented SN38 prodrug delivery nanoplatform for targeted gastric cancer therapy

Most cancer cells employ overexpression of glucose transports (GLUTs) to satisfy glucose demand ("Sweet Tooth") for increased aerobic glycolysis rates. GLUT1, one of the most widely expressed GLUTs in numerous cancers, was identified as a prognosis-related biomarker of gastric cancer via tissue array analysis. Herein, a "Sweet Tooth"-oriented SN38 prodrug delivery nanoplatform (Glu-SNP) was developed for targeted gastric cancer therapy. For this purpose, a SN38-derived prodrug (PLA-SN38) was synthesized by tethering 7-ethyl-10-hydroxycamptothecin (SN38) to biocompatible polylactic acid (PLA) with the appropriate degree of polymerization (n = 44). The PLA-SN38 conjugate was further assembled with glycosylated amphiphilic lipid to obtain glucosamine-decorated nanoparticles (Glu-SNP). Glu-SNP exhibited potent antitumor efficiency both in vitro and in vivo through enhanced cancer cell-specific targeting associated with the overexpression of GLUT1, which provides a promising approach for gastric cancer therapy.

CircCTNNA1 acts as a ceRNA for miR-363-3p to facilitate the progression of colorectal cancer by promoting CXCL5 expression

Background

Circular RNAs (circRNA) have been shown to be involved in the pathogenesis of colorectal cancer (CRC). CircCTNNA1 was found to be one of the upregulated circRNAs in CRC. However, there are few studies on circCTNNA1, so it is necessary to carry out further studies.

Methods

The expression of circCTNNA1, microRNA (miR)-363-3p, and chemokine C-X-C motif ligand 5 (CXCL5) was detected by quantitative real-time PCR (qRT-PCR). The protein levels of CXCL5 and metastasis markers were measured using western blot (WB) analysis. Cell proliferation, apoptosis, cell cycle, migration, and invasion were determined by cell counting kit 8 (CCK8) assay, colony formation assay, flow cytometry, and transwell assay. The relationship between miR-363-3p and circCTNNA1 or CXCL5 was evaluated via dual-luciferase reporter assay and RNA immunoprecipitation assay. Animal study was performed to explore the function of circCTNNA1 on CRC tumorigenesis.

Results

CircCTNNA1 and CXCL5 were highly expressed in CRC. Knockdown of circCTNNA1 could inhibit the proliferation, cell cycle, metastasis, and promote the apoptosis of CRC cells. MiR-363-3p could be sponged by circCTNNA1, and the inhibition effect of circCTNNA1 silencing on CRC progression could be reversed by miR-363-3p inhibitor. Moreover, miR-363-3p could interact with CXCL5, and CXCL5 overexpression also could reverse the suppressive effect of miR-363-3p on CRC progression. Downregulation of circCTNNA1 also could hinder the tumor growth of CRC in vivo.

Conclusion

CircCTNNA1 enhanced CRC progression via regulating the miR-363-3p/CXCL5 axis.

MicroRNA-26b-5p alleviates cerebral ischemia-reperfusion injury in rats via inhibiting the N-myc/PTEN axis by downregulating KLF10 expression

MicroRNAs plays important role in cerebral ischemia-reperfusion (CIR). However, the role of miR-26b-5p in CIR injury remains unclear. PC12 cells were treated with oxygen-glucose deprivation (OGD) for 0 h, 2 h, 4 h, 6 h, and then reoxygenated for 24 h to construct an in vitro I/R model. Then, miR-26b-5p mimic, small interfering RNA of KLF10 and KLF10 overexpression plasmid were transfected into cells respectively for mechanism study. Our results showed that miR-26b-5p was downregulated in OGD/R-induced PC12 cells. After overexpression of miR-26b-5p, cell proliferation ability was enhanced, apoptosis, ROS and inflammatory mediators were inhibited. Bioinformatics analysis indicated that miR-26b-5p was directly bound to the 3' UTR of KLF10, and downregulated the expression of KLF10. KLF10 was upregulated in OGD/R cells, and transfection with si-KLF10 promoted cell proliferation and reduced apoptosis, NO concentration and inflammatory factor secretion. Moreover, pcDNA-KLF10 reversed the inhibitory effects of miR-26b-5p mimic on apoptosis, NO content and inflammatory factor secretion, as well as the downregulation of N-myc and PTEN expression. Meanwhile, I/R rat models were constructed and divided into sham operation group (femoral artery isolation only), model group (middle cerebral artery occlusion model of rats was prepared by thread embolization), treatment group (200 µL of miR-26b-5p mimic was injected into the brain of model rats). We observed that the infarct size of brain tissue was reduced, KLF10 expression was downregulated, and apoptosis and inflammatory response were reduced. These results suggest that miR-26b-5p had protective effects on CIRI and it may be a potential treatment target.

Effect of the BBC3 Gene on the Proliferation and Apoptosis of Hepatocellular Carcinoma Cells Through p53-Regulated Signaling

We examined the effect of the BBC3 gene on hyperplasia and apoptosis in HepG2 cells and its underlying mechanism. Quantitative RT-PCR was used to determine the level of BBC3 expression in HL-7702 normal human liver cells and four different hepatocellular carcinoma cell lines (HepG2, HuH-7, HCCLM3 and MHCC97H). Transfection was performed with Lipofectamine 2000 reagent and the transfectants were divided into three groups: pcDNA-BBC3 group (transfected BBC3 over-expressing plasmid), pcDNA-NC group (transfected empty plasmid), and a Ctrl group (not transfected). Quantitative RT-PCR and western blot analysis were used to measure BBC3 expression. The CCK-8 assay was used to determine the effect of BBC3 on HepG2 cell proliferation. Flow cytometry was used for testing the effect of overexpressing BBC3 on apoptosis in HepG2 cells. The levels of cleaved-Caspase-3 (C-Caspase-3), cleaved-Caspase-9 (C-Caspase-9), and proteins associated with the p53 signaling pathway were assessed by western blot analysis. The level of BBC3 mRNA in HL-7702 normal human liver cells was significantly higher compared with that in human hepatocellular carcinoma cells including HepG2, HuH-7, HCCLM3 and MHCC97H (P < 0.05). The lowest level of BBC3 mRNA was observed in HepG2 cells. The level of BBC3 mRNA and protein in HepG2 cells were significantly higher compared with that of the pcDNA-NC group following transfection with a BBC3 overexpressing plasmid. HepG2 cell proliferation in the pcDNA-NC group was higher compared with that of the pcDNA-BBC3-transfected group (P < 0.05). The apoptotic rate and levels of cleaved-Caspase-3, cleaved-Caspase-9, p53, phospho-p53, and p21 protein in cells were higher compared with that of the pcDNA-NC group. No change was observed in the pcDNA-NC and Ctrl groups. The BBC3 gene was down-regulated in hepatocellular carcinoma cells. HepG2 cell proliferation can be inhibited and HepG2 cell apoptosis can be induced by the overexpression of BBC3 through activation of the p53 signaling pathway.

High resolution mapping of nighttime light and air pollutants during the COVID-19 lockdown in Wuhan

The novel coronavirus (COVID-19) has induced unprecedented improvements of air quality due to drastic shrinking of human activities during the pandemic lockdown in 2020. While declines of most air pollutants have been globally evidenced in most cities worldwide, there is few detailed spatial knowledge at local scale. Therefore, we present here a high resolution mapping of the 2018-2020 evolution of human activities and air pollutants in Wuhan. Human activities were assessed by nighttime light radiance. We measured the air quality index (AQI) as the maximum value among air quality sub-indices of SO₂, NO₂, CO, O₃ and particulate matter. We also compared mean monthly pollutant concentration during January-April in 2018, 2019 and 2020. Mapping results show that variations of nighttime light radiance were heterogenous at local scale, showing both rises and declines in the same district. The radiance decreased in eight districts located mostly in the city center, as a result of lower human activity, but the radiance increased in the five surrounding districts, as a consequence of people staying at home. AQI was low during lockdown, averaging at 57, but showed strong daily variations with a slight pollution around February 5 with AQI rising to 126. During this pollution event, particulate matter, SO₂, NO₂ and CO levels were positively correlated, suggesting common sources, but were not correlated with ozone; and particulate matter, SO₂, NO₂ and CO decreased with relative humidity, suggesting removal by precipitation. Comparison of 2020 data with previous years shows that particulate matter and NO₂ were highly reduced, CO was less reduced due to ongoing power industries, SO₂ first declined then increased to exceed 2018-19 values due to coal combustion, and ozone levels was more abundant due both to less NO_x pollution and the weekend effect.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10311-021-01222-x.

A clinical model to predict distant metastasis in patients with superficial gastric cancer with negative lymph node metastasis and a survival analysis for patients with metastasis

BACKGROUND

Distant metastasis (DM) is relatively rare in superficial gastric cancer (SGC), especially in patients without lymph node metastasis. This study aimed to explore the main clinical risk factors for DM in patients with superficial gastric cancer-no lymph node metastasis (SGC-NLNM) and the prognostic factors for patients with DM.

METHODS

Records of patients with SGC-NLNM between 2004 and 2015 were collected from the public Surveillance, Epidemiology, and End Results (SEER) database. Both univariate and multivariate logistic regressions were performed to analyze the clinical risk factors for DM. The Kaplan-Meier method and Cox regression model were used to identify prognostic factors for patients with DM. A nomogram was built based on multivariate logistic regression and evaluated by the C-index, the calibration, and the area under the receiver operating characteristic curve (AUC).

RESULTS

We developed and validated a nomogram to predict DM in patients with SGC-NLNM, showing that race, age, primary site, depth, size, and grade were independent risk factors. The built nomogram had a good discriminatory performance, with a C-index of 0.836 (95% confidence interval [CI]: 0.813-0.859). Calibration plots showed that the predicted DM probability was identical to the actual observations in both the training and validation sets. AUC was 0.846 (95% CI: 0.820-0.871) and 0.801 (95% CI: 0.751-0.850) in the training and validation sets, respectively. The results of the survival analysis revealed that surgery (hazard ratio [HR] = 0.249; 95% CI, 0.125-0.495), chemotherapy (HR = 0.473; 95% CI, 0.353-0.633), and grade (HR = 1.374; 95% CI, 1.018-1.854) were independent prognostic factors associated with cancer-specific survival (CSS), but radiotherapy was not (log-rank test, p = 0.676).

CONCLUSIONS

We constructed a sensitive and discriminative nomogram to identify high-risk patients with SGC-NLNM who may harbor dissemination at initial diagnosis. The tumor size and primary site were the largest contributors to DM prediction. Compared with radiotherapy, aggressive surgery, and chemotherapy may be better options for patients with DM.