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Chronic inflammation is positively associated with the development of urinary bladder cancer. However, its detailed regulatory mechanism remains elusive. The quantitative real-time polymerase chain reaction was used to measure mRNA levels of relative genes. The protein levels were monitored by western blotting. Cell proliferation and viability were evaluated by the cell counting Kit 8 (CCK8) and colony formation assays, respectively. The dual-luciferase reporter assay was performed to assay the transcriptional activity.

Autism spectrum disorder (ASD) is a highly heritable neurodevelopmental disorder. Large genetically informative cohorts of individuals with ASD have led to the identification of a limited number of common genome-wide significant (GWS) risk loci to date. However, many more common genetic variants are expected to contribute to ASD risk given the high heritability. Here, we performed a genome-wide association study (GWAS) on 6222 case-pseudocontrol pairs from the Simons Foundation Powering Autism Research for Knowledge (SPARK) dataset to identify additional common genetic risk factors and molecular mechanisms underlying risk for ASD. We identified one novel GWS locus from the SPARK GWAS and four significant loci, including an additional novel locus from meta-analysis with a previous GWAS. We replicated the previous observation of significant enrichment of ASD heritability within regulatory regions of the developing cortex, indicating that disruption of gene regulation during neurodevelopment is critical for ASD risk. We further employed a massively parallel reporter assay (MPRA) and identified a putative causal variant at the novel locus from SPARK GWAS with strong impacts on gene regulation (rs7001340). Expression quantitative trait loci data demonstrated an association between the risk allele and decreased expression of DDHD2 (DDHD domain containing 2) in both adult and prenatal brains. In conclusion, by integrating genetic association data with multi-omic gene regulatory annotations and experimental validation, we fine-mapped a causal risk variant and demonstrated that DDHD2 is a novel gene associated with ASD risk.

Most loci identified by GWASs have been found in populations of European ancestry (EUR). In trans-ethnic meta-analyses for 15 hematological traits in 746,667 participants, including 184,535 non-EUR individuals, we identified 5,552 trait-variant associations at p < 5 × 10-9, including 71 novel associations not found in EUR populations. We also identified 28 additional novel variants in ancestry-specific, non-EUR meta-analyses, including an IL7 missense variant in South Asians associated with lymphocyte count in vivo and IL-7 secretion levels in vitro. Fine-mapping prioritized variants annotated as functional and generated 95% credible sets that were 30% smaller when using the trans-ethnic as opposed to the EUR-only results. We explored the clinical significance and predictive value of trans-ethnic variants in multiple populations and compared genetic architecture and the effect of natural selection on these blood phenotypes between populations. Altogether, our results for hematological traits highlight the value of a more global representation of populations in genetic studies.

Modulating the reaction selectivity is highly attractive and pivotal to the rational design of synthetic regimes. The defluorinative functionalization of gem-difluorocyclopropanes constitutes a promising route to construct β-vinyl fluorine scaffolds, whereas chemo- and regioselective access to α-substitution patterns remains a formidable challenge. Presented herein is a robust Pd/NHC ligand synergistic strategy that could enable the C–F bond functionalization with exclusive α-regioselectivity with simple ketones. The key design adopted enolates as π-conjugated ambident nucleophiles that undergo inner-sphere 3,3′-reductive elimination warranted by the sterically hindered-yet-flexible Pd-PEPPSI complex. The excellent branched mono-defluorinative alkylation was achieved with a sterically highly demanding IHept ligand, while subtly less bulky SIPr acted as a bifunctional ligand that not only facilitated α-selective C(sp3)–F cleavage, but also rendered the newly-formed C(sp2)–F bond as the linchpin for subsequent C–O bond formation. These examples represented an unprecedented ligand-controlled regioselective and chemodivergent approach to various mono-fluorinated terminal alkenes and/or furans from the same readily available starting materials., A robust Pd/NHC ligand synergistic strategy that enables the exquisite regioselective and chemodivergent C–F bond functionalization of gem-difluorocyclopropanes with simple ketones, is reported.

Background: Thousands of genetic variants have been associated with hematological traits, though target genes remain unknown at most loci. Also, limited analyses have been conducted in African ancestry and Hispanic/Latino populations; hematological trait associated variants more common in these populations have likely been missed. Methods: To derive gene expression prediction models, we used ancestry-stratified datasets from the Multi-Ethnic Study of Atherosclerosis (MESA, including N=229 African American and N=381 Hispanic/Latino participants, monocytes) and the Depression Genes and Networks study (DGN, N = 922 European ancestry participants, whole blood). We then performed a transcriptome-wide association study (TWAS) for platelet count, hemoglobin, hematocrit, and white blood cell count in African (N = 27,955) and Hispanic/Latino (N = 28,324) ancestry participants. Results: Our results revealed 24 suggestive signals (p < 1×10^(-4)) that were conditionally distinct from known GWAS identified variants and successfully replicated these signals in European ancestry subjects from UK Biobank. We found modestly improved correlation of predicted and measured gene expression in an independent African American cohort (the Genetic Epidemiology Network of Arteriopathy (GENOA) study (N=802), lymphoblastoid cell lines) using the larger DGN reference panel; however, some genes were well predicted using MESA but not DGN. Conclusions: These analyses demonstrate the importance of performing TWAS and other genetic analyses across diverse populations and of balancing sample size and ancestry background matching when selecting a TWAS reference panel.

SummaryBlood cells play essential roles in human health, underpinning physiological processes such as immunity, oxygen transport, and clotting, which when perturbed cause a significant health burden. Here we integrate data from UK Biobank and a large-scale international collaborative effort, including 563,946 European ancestry participants, and discover 5,106 new genetic variants independently associated with 29 blood cell phenotypes covering the full allele frequency spectrum of variation impacting hematopoiesis. We holistically characterize the genetic architecture of hematopoiesis, assess the relevance of the omnigenic model to blood cell phenotypes, delineate relevant hematopoietic cell states influenced by regulatory genetic variants and gene networks, identify novel splice-altering variants mediating the associations, and assess the polygenic prediction potential for blood cell traits and clinical disorders at the interface of complex and Mendelian genetics. These results show the power of large-scale blood cell GWAS to interrogate clinically meaningful variants across the full allelic spectrum of human variation.

An ever-increasing deluge of single-cell RNA-sequencing (scRNA-seq) data has been generated, often involving different time points, laboratories or sequencing protocols. Batch effect correction has been recognized to be indispensable when integrating scRNA-seq data from multiple batches. A recent study proposed an effective correction method based on mutual nearest neighbors (MNN) across batches. However, the proposed MNN method is unsupervised in that it ignores cluster label information of single cells. Such cluster or cell type label information can further improve effectiveness of batch effect correction, particularly under realistic scenarios where true biological differences are not orthogonal to batch effect. Under this motivation, we propose SMNN which performs supervised mutual nearest neighbor detection for batch effect correction of scRNA-seq data. Our SMNN either takes cluster/cell-type label information as input, or, in the absence of such information, infers cell types by performing clustering of scRNA-seq data. It then detects mutual nearest neighbors within matched cell types and corrects batch effect accordingly. Our extensive evaluations in simulated and real datasets show that SMNN provides improved merging within the corresponding cell types across batches, leading to reduced differentiation across batches over MNN. Furthermore, SMNN retains more cell type-specific features after correction. Differentially expressed genes (DEGs) identified between cell types after SMNN correction are biologically more relevant, and the DEG true positive rates improve by up to 841%. SMNN is implemented in R, and freely available at https://yunliweb.its.unc.edu/SMNN/ and https://github.com/yycunc/SMNNcorrect . Author summary The presence of batch effects poses grand challenges to integrative analysis of scRNA-seq data from multiple resources. One powerful tool MNN corrects batch effect of scRNA-seq data based on mutual nearest neighbors across batches. However, this method makes a critical assumption that batch effect is orthogonal to true biological differences. This assumption in practice can easily be violated. When that happens, MNN suffers from biases introduced by wrongly matched pairs of cells. To overcome this shortcoming, here we present a new method, SMNN, which performs supervised mutual nearest neighbor detection for batch effect correction. We benchmark the performance of SMNN using both simulations and real data, and demonstrate that, compared to MNN, our SMNN can better mix cells of the same type/state across batches. More importantly, SMNN can more effectively retain biologically relevant features, and thereof provide improved cell type clustering and enhanced power for detecting differentially expressed genes (DEGs) between different cell types.

BackgroundAutism spectrum disorder (ASD) is a highly heritable neurodevelopmental disorder. Large genetically informative cohorts of individuals with ASD have led to the identification of three common genome-wide significant (GWS) risk loci to date. However, many more common genetic variants are expected to contribute to ASD risk given the high heritability. Here, we performed a genome-wide association study (GWAS) using the Simons Foundation Powering Autism Research for Knowledge (SPARK) dataset to identify additional common genetic risk factors and molecular mechanisms underlying risk for ASD.MethodsWe performed an association study on 6,222 case-pseudocontrol pairs from SPARK and meta-analyzed with a previous GWAS. We integrated gene regulatory annotations to map non-coding risk variants to their regulated genes. Further, we performed a massively parallel reporter assay (MPRA) to identify causal variant(s) within a novel risk locus.ResultsWe identified one novel GWS locus from the SPARK GWAS. The meta-analysis identified four significant loci, including an additional novel locus. We observed significant enrichment of ASD heritability within regulatory regions of the developing cortex, indicating that disruption of gene regulation during neurodevelopment is critical for ASD risk. The MPRA identified one variant at the novel locus with strong impacts on gene regulation (rs7001340), and expression quantitative trait loci data demonstrated an association between the risk allele and decreased expression of DDHD2 (DDHD domain containing 2) in both adult and pre-natal brains.ConclusionsBy integrating genetic association data with multi-omic gene regulatory annotations and experimental validation, we fine-mapped a causal risk variant and demonstrated that DDHD2 is a novel gene associated with ASD risk.

Summary Blood cells play essential roles in human health, underpinning physiological processes such as immunity, oxygen transport, and clotting, which when perturbed cause a significant global health burden. Here we integrate data from UK Biobank and a large-scale international collaborative effort, including data for 563,085 European ancestry participants, and discover 5,106 new genetic variants independently associated with 29 blood cell phenotypes covering a range of variation impacting hematopoiesis. We holistically characterize the genetic architecture of hematopoiesis, assess the relevance of the omnigenic model to blood cell phenotypes, delineate relevant hematopoietic cell states influenced by regulatory genetic variants and gene networks, identify novel splice-altering variants mediating the associations, and assess the polygenic prediction potential for blood traits and clinical disorders at the interface of complex and Mendelian genetics. These results show the power of large-scale blood cell trait GWAS to interrogate clinically meaningful variants across a wide allelic spectrum of human variation., Graphical Abstract, Highlights • Largest genome-wide association study of blood cell traits to date • Empiric assessments of omnigenic and infinitesimal models of polygenic variation • Functional insights into how genetic variants impact human hematopoiesis • Assessment of the effect of polygenic trait scores upon blood diseases, Analysis of blood cell traits in the UK Biobank and other cohorts illuminates the full genetic architecture of hematopoietic phenotypes, with evidence supporting the omnigenic model for complex traits and linking polygenic burden with monogenic blood diseases.

Background: Thousands of genetic variants have been associated with hematological traits, though target genes remain unknown at most loci. Moreover, limited analyses have been conducted in African ancestry and Hispanic/Latino populations; hematological trait associated variants more common in these populations have likely been missed. Methods: To derive gene expression prediction models, we used ancestry-stratified datasets from the Multi-Ethnic Study of Atherosclerosis (MESA, including n = 229 African American and n = 381 Hispanic/Latino participants, monocytes) and the Depression Genes and Networks study (DGN, n = 922 European ancestry participants, whole blood). We then performed a transcriptome-wide association study (TWAS) for platelet count, hemoglobin, hematocrit, and white blood cell count in African (n = 27,955) and Hispanic/Latino (n = 28,324) ancestry participants. Results: Our results revealed 24 suggestive signals (p < 1 × 10−4) that were conditionally distinct from known GWAS identified variants and successfully replicated these signals in European ancestry subjects from UK Biobank. We found modestly improved correlation of predicted and measured gene expression in an independent African American cohort (the Genetic Epidemiology Network of Arteriopathy (GENOA) study (n = 802), lymphoblastoid cell lines) using the larger DGN reference panel; however, some genes were well predicted using MESA but not DGN. Conclusions: These analyses demonstrate the importance of performing TWAS and other genetic analyses across diverse populations and of balancing sample size and ancestry background matching when selecting a TWAS reference panel.

Most genome-wide association and fine-mapping studies to date have been conducted in individuals of European descent, and genetic studies of populations of Hispanic/Latino and African ancestry are limited. In addition, these populations have more complex linkage disequilibrium structure. In order to better define the genetic architecture of these understudied populations, we leveraged >100,000 phased sequences available from deep-coverage whole genome sequencing through the multi-ethnic NHLBI Trans-Omics for Precision Medicine (TOPMed) program to impute genotypes into admixed African and Hispanic/Latino samples with genome-wide genotyping array data. We demonstrated that using TOPMed sequencing data as the imputation reference panel improves genotype imputation quality in these populations, which subsequently enhanced gene-mapping power for complex traits. For rare variants with minor allele frequency (MAF) < 0.5%, we observed a 2.3- to 6.1-fold increase in the number of well-imputed variants, with 11–34% improvement in average imputation quality, compared to the state-of-the-art 1000 Genomes Project Phase 3 and Haplotype Reference Consortium reference panels. Impressively, even for extremely rare variants with minor allele count 86%. Subsequent association analyses of TOPMed reference panel-imputed genotype data with hematological traits (hemoglobin (HGB), hematocrit (HCT), and white blood cell count (WBC)) in ~21,600 African-ancestry and ~21,700 Hispanic/Latino individuals identified associations with two rare variants in the HBB gene (rs33930165 with higher WBC [p = 8.8x10-15] in African populations, rs11549407 with lower HGB [p = 1.5x10-12] and HCT [p = 8.8x10-10] in Hispanics/Latinos). By comparison, neither variant would have been genome-wide significant if either 1000 Genomes Project Phase 3 or Haplotype Reference Consortium reference panels had been used for imputation. Our findings highlight the utility of the TOPMed imputation reference panel for identification of novel rare variant associations not previously detected in similarly sized genome-wide studies of under-represented African and Hispanic/Latino populations., Author summary Admixed African and Hispanic/Latino populations remain understudied in genetic studies of complex diseases. These populations have more complex linkage disequilibrium (LD) structure that can impair mapping of variants. Genotype imputation represents an approach to improve genome coverage, especially for rare or ancestry-specific variation; however, these understudied populations also have smaller relevant imputation reference panels. In this study, we leveraged >100,000 phased sequences generated from the multi-ethnic NHLBI TOPMed project for imputation in ~21,600 individuals of African ancestry (AAs) and ~21,700 Hispanics/Latinos. We demonstrated substantially higher imputation quality for low frequency and rare variants in comparison to the 1000 Genomes Project and Haplotype Reference Consortium reference panels. Analysis of quantitative hematological traits led to the discovery of associations with two rare variants in the HBB gene; one of these variants was replicated in an independent sample, and the other is known to cause anemia in the homozygous state. By comparison, the same HBB variants would not have been genome-wide significant using current reference panels due to lower imputation quality. Our findings demonstrate the power of TOPMed whole genome sequencing data for imputation and subsequent association analysis in admixed African and Hispanic/Latino populations.

BackgroundGenetic factors that influence kidney traits have been understudied for low frequency and ancestry-specific variants.MethodsWe combined whole genome sequencing (WGS) data from 23,732 participants from 10 NHLBI Trans-Omics for Precision Medicine (TOPMed) Program multi-ethnic studies to identify novel loci for estimated glomerular filtration rate (eGFR). Participants included European, African, East Asian, and Hispanic ancestries. We applied linear mixed models using a genetic relationship matrix estimated from the WGS data and adjusted for age, sex, study, and ethnicity.FindingsWhen testing single variants, we identified three novel loci driven by low frequency variants more commonly observed in non-European ancestry (PRKAA2, rs180996919, minor allele frequency [MAF] 0.04%, P=6.1×10-11; METTL8, rs116951054, MAF 0.09%, P=4.5×10-9; and MATK, rs539182790, MAF 0.05%, P=3.4×10-9). We also replicated two known loci for common variants (rs2461702, MAF=0.49, P=1.2×10-9, nearest gene GATM, and rs71147340, MAF=0.34, P=3.3×10-9, CDK12). Testing aggregated variants within a gene identified the MAF gene. A statistical approach based on local ancestry helped to identify replication samples for ancestry-specific variants.InterpretationThis study highlights challenges in studying variants influencing kidney traits that are low frequency in populations and more common in non-European ancestry.

IMPORTANCE: APOL1 genotypes are associated with kidney diseases in African American individuals and may influence cardiovascular disease and mortality risk, but findings have been inconsistent. OBJECTIVE: To discern whether high-risk APOL1 genotypes are associated with cardiovascular disease and stroke in postmenopausal African American women, who are at high risk for these outcomes. DESIGN, SETTING, AND PARTICIPANTS: The Women's Health Initiative is a prospective cohort that enrolled 161 838 postmenopausal women into clinical trials and an observational study between 1993 and 1998. This study includes 11 137 African American women participants who had a clinical event from enrollment to June 2014. Data analyses were completed from January 2017 to August 2017. EXPOSURES: The variants of APOL1 were genotyped or imputed from whole-exome sequencing. MAIN OUTCOMES AND MEASURES: Incident coronary heart disease, stroke and heart failure subtypes, and overall and cause-specific mortality were adjudicated from hospital records and death certificates. Estimated incidence rates were determined for each outcome and hazard ratios (HR) and 95% CIs for the associations of APOL1 groups with outcomes. RESULTS: The mean (SD) age of participants was 61.7 (7.1) years. Carriers of high-risk APOL1 variants (n = 1370; 12.3%) had higher prevalence of hypertension, use of cholesterol-lowering medications, and reduced estimated glomerular filtration rate (eGFR). After a mean (SD) of 11.0 (3.6) years, carriers of high-risk APOL1 variants had a higher incidence rate of hospitalized heart failure with preserved ejection fraction (HFpEF) than low-risk carriers did but showed no differences for other outcomes. In adjusted models, there was a significant 58% increased hazard of hospitalized HFpEF (HR, 1.58 [95% CI, 1.03-2.41]) among carriers of high-risk APOL1 variants compared with carriers of low-risk APOL1 variants. The association with HFpEF was attenuated (HR = 1.50 [95% CI, 0.98-2.30]) and no longer significant when adjusting for baseline eGFR. CONCLUSIONS AND RELEVANCE: Status as a carrier of a high-risk APOL1 genotype was associated with HFpEF hospitalization among postmenopausal women, which is partly accounted for by baseline kidney function. These findings do not support an association of high-risk APOL1 genotypes with coronary heart disease, stroke, or mortality in postmenopausal African American women.

The purpose of this study was to evaluate the safety and efficacy of the modified lateral transperitoneal (MLTP) approach in comparison with the traditional lateral transperitoneal (LTP) and lateral retroperitoneal (LRP) approach. From January 2008 to December 2012, 287 patients underwent laparoscopic adrenalectomy, and the MLTP, LTP and LRP approaches were used in 93, 96 and 98 patients. The patients’ demographics and surgical outcomes from the three approaches were reviewed and compared. There were no significant differences in the general demographic or postoperative recovery variables among the three groups. However, the average volume of blood lost was lower for the MLTP group than for the other two groups. Additionally, the average operative time was significantly shorter in the MLTP group than in the LTP group and slightly shorter than in the LRP group, but the differences were not statistically significant. This study shows that the MLTP approach is a safe and effective procedure which is associated with shorter operative time and lower volumes of blood loss.

Aim The aim of the present study was to review our 5-year experience and compare the outcomes of flexible ureteroscopy (fURS) and percutaneous nephrolithotomy (PCNL) for treating 10–20-mm renal stones. Patients and Methods In this retrospective study, we compared 310 patients with renal stones of 10–20-mm size treated with PCNL (n = 164) or fURS (n = 175) between March 2008 and March 2013. The parameters of patients included age, body mass index and sex, as well as the size, location, and previous stone treatments. Factors, such as operation duration, hospitalization time, drop in haemoglobin level, complications, stone-free rate (SFR) and necessitating blood transfusion were analysed. Results The two groups had comparable demographic data, such as age, sex, stone size and localization. The mean operation duration for PCNL was 52.6 min, and for fURS, 81.3 min (P 0.05). The SFR was 82.3 per cent after fURS and 91.4 per cent after PCNL at the first day, postoperatively (P > 0.05). Four weeks after the staged procedure, the SFR was 96.4 per cent after fURS and 97.7 per cent after PCNL (P > 0.05). After the second-stage procedure, the SFR was significantly higher than that at the first day, postoperatively, in the fURS group (82.3 per cent vs 96.4 per cent, P

Hypoxia stimulates angiogenesis under a variety of pathological conditions, including malignant tumors by inducing expression of angiogenic factors such as VEGFA. Surprisingly, here we report significant association between down-regulation of a new angiogenic factor AGGF1 and high-grade urothelial carcinoma. The proportion of strong AGGF1 expression cases was significantly lower in the high-grade urothelial carcinoma group than that in the low-grade urothelial carcinoma group (P=1.40×10−5) or than that in the normal urothelium tissue group (P=2.11×10−4). We hypothesized that tumor hypoxia was responsible for differential expression of the AGGF1 protein in low- and high-grade urothelial carcinomas, and therefore investigated the molecular regulatory mechanism for AGGF1 expression under hypoxia. Under hypoxic conditions, AGGF1 protein levels declined without any change in mRNA levels and protein stability. Hypoxia-induced down-regulation of AGGF1 was mediated by miR-27a. Overexpression of miR-27a suppressed AGGF1 expression through translational inhibition, but not by RNA degradation. Moreover, the hypoxia-induced decrease of AGGF1 expression disappeared after miR-27a expression was inhibited. Furthermore, down-regulation of AGGF1 reduced hypoxia-induced apoptosis in cancer cells. Taken together, the results of this study indicate that (1) hypoxia down-regulates expression of the AGGF1 protein, but not AGGF1 mRNA, by inducing expression of miR-27a; (2) Down-regulation of AGGF1 had an apparent protective role for cancer cells under hypoxia; (3) Down-regulation of the AGGF1 protein confers a significant risk of high-grade human urothelial bladder carcinoma.

Purpose: Some microRNA (miRNA) levels have been found to be dysregulated in cancer patients, suggesting the potential usefulness of miRNAs in cancer therapies. The purpose of this study was to investigate the expression of miR-142-5p in human renal cell carcinoma (RCC) and its potential role in tumor growth and metastasis. Methods: The expression level of miR-142-5p in human RCC tissue and cell lines was determined by quantitative reverse transcription polymerase chain reaction analysis. MTT, colony formation, Transwell, and cell cycle assays were performed to explore the potential functions of miR-142-5p in human RCC cells. The potential target gene of miR-142-5p was identified and confirmed via luciferase reporter assays. Results: miR-142-5p expression was elevated in RCC tissues and cell lines. Overexpression of miR-142-5p significantly promoted cell proliferation and colony formation and could prevent G1 phase arrest among RCC 786-O cells. Meanwhile, the migration potential of 786-O cells was greater than that of control cells. BTG3 was identified as a direct target of miR-142-5p, and re-expression of BTG3 reversed the miR-142-5p-induced cell proliferation. Conclusion: miR-142-5p promoted the proliferation and migration of RCC cells by targeting BTG3. With this potential onco-miRNA role in the progression of RCC, miR-142-5p may be a therapeutic target for the treatment of RCC.

Supplemental Digital Content is available in the text, Background: Premature ejaculation (PE) is the most prevalent male sexual dysfunction. Epidemiologic findings are inconsistent concerning the risk for depression associated with PE. Objective: The aim of this study was to investigate the potential association between between depression and risk of PE. Data sources: We conducted a literature search of PubMed, Embase, and the Cochrane Library from these databases’ inception through June 2014 for observational epidemiological studies examining the association between depression on risk of PE. Study eligibility criteria: Studies were selected if they reported the risk estimates for PE associated with depression. Participants: patients>18 years of age suffering from PE. Interventions: a history of depressive disorder. Study appraisal and synthesis methods: These odds ratios (ORs) were pooled using a random or fixed effects model and were tested for heterogeneity. Subgroup analysis was employed to explore heterogeneity. Results: Eight trials involving 18,035 patients were included in the meta-analysis. Depression were statistically significantly associated with the risk of PE (OR = 1.63, 95% CI:1.42–1.87). There was no evidence of between-study heterogeneity (P = 0.623, I2 = 0.0%). The association was similar when stratified by mean age, geographical area, study design, sample size, publication year, and controlling key confounders. Limitations: The severity of depression and PE could not be identified due to unavailable data of trials. No evidence of publication bias was observed. Conclusions: These findings provide evidence that depression is associated with a significantly increased risk of PE. In addition, more prospective studies are necessary to evaluate the association and identify the ideal treatment. Systematic review registration number: CRD42016041272