Spatiotemporal ATF3 Expression Determines VSMC Fate in Abdominal Aortic Aneurysm.

BACKGROUND: Abdominal aortic aneurysm (AAA) is a catastrophic disease with little effective therapy, likely due to the limited understanding of the mechanisms underlying AAA development and progression. ATF3 (activating transcription factor 3) has been increasingly recognized as a key regulator of cardiovascular diseases. However, the role of ATF3 in AAA development and progression remains elusive. METHODS: Genome-wide RNA sequencing analysis was performed on the aorta isolated from saline or Ang II (angiotensin II)-induced AAA mice, and ATF3 was identified as the potential key gene for AAA development. To examine the role of ATF3 in AAA development, vascular smooth muscle cell-specific ATF3 knockdown or overexpressed mice by recombinant adeno-associated virus serotype 9 vectors carrying ATF3, or shRNA-ATF3 with SM22α (smooth muscle protein 22-α) promoter were used in Ang II-induced AAA mice. In human and murine vascular smooth muscle cells, gain or loss of function experiments were performed to investigate the role of ATF3 in vascular smooth muscle cell proliferation and apoptosis. RESULTS: In both Ang II-induced AAA mice and patients with AAA, the expression of ATF3 was reduced in aneurysm tissues but increased in aortic lesion tissues. The deficiency of ATF3 in vascular smooth muscle cell promoted AAA formation in Ang II-induced AAA mice. PDGFRB (platelet-derived growth factor receptor ß) was identified as the target of ATF3, which mediated vascular smooth muscle cell proliferation in response to TNF-alpha (tumor necrosis factor-α) at the early stage of AAA. ATF3 suppressed the mitochondria-dependent apoptosis at the advanced stage by upregulating its direct target BCL2. Our chromatin immunoprecipitation results also demonstrated that the recruitment of NFκB1 and P300/BAF/H3K27ac complex to the ATF3 promoter induces ATF3 transcription via enhancer activation. NFKB1 inhibitor (andrographolide) inhibits the expression of ATF3 by blocking the recruiters NFKB1 and ATF3-enhancer to the ATF3-promoter region, ultimately leading to AAA development. CONCLUSIONS: Our results demonstrate a previously unrecognized role of ATF3 in AAA development and progression, and ATF3 may serve as a novel therapeutic and prognostic marker for AAA.

RAE1 promotes nitrosamine-induced malignant transformation of human esophageal epithelial cells through PPARα-mediated lipid metabolism.

Esophageal cancer (EC) is the sixth cause of cancer-related deaths and still is a significant public health problem globally. Nitrosamines exposure represents a major health concern increasing EC risks. Exploring the mechanisms induced by nitrosamines may contribute to the prevention and early detection of EC. However, the mechanism of nitrosamine carcinogenesis remains unclear. Ribonucleic acid export 1 (RAE1), has an important role in mediating diverse cancer types, but, to date, there has been no study for any functional role of RAE1 in esophageal carcinogenesis. Here, we successfully verified the nitrosamine-induced malignant transformation cell (MNNG-M) by xenograft tumor model, based on which it was found that RAE1 was upregulation in the early stage of nitrosamine-induced esophageal carcinogenesis and EC tissues. RAE1 knockdown led to severe blockade in G2/M phase and significant inhibition of proliferation of MNNG-M cells, whereas RAE1 overexpression had the opposite effect. In addition, peroxisome proliferator-activated receptor-alpha (PPARα), was demonstrated as a downstream target gene of RAE1, and its down-regulation reduced lipid accumulation, resulting in causing cells accumulation in the G2/M phase. Mechanistically, we found that RAE1 regulates the lipid metabolism by maintaining the stability of PPARα mRNA. Taken together, our study reveals that RAE1 promotes malignant transformation of human esophageal epithelial cells (Het-1A) by regulating PPARα-mediated lipid metabolism to affect cell cycle progression, and offers a new explanation of the mechanisms underlying esophageal carcinogenesis.

Global burden and trends of firearm violence in 204 countries/territories from 1990 to 2019.

Background: Gaps remained in the updated information of the firearm violence (FV) burden from a global landscape. Understanding the global burden of FV could contribute to decision-making. Methods: Data on the FV burden, including physical violence by firearm (PVF), self-harm by firearm (SHF), and unintentional firearm injuries (UFI), were extracted from the Global Burden of Disease 2019. The temporal trends of age-standardized rate (ASR) were estimated using estimated annual percentage change (EAPC). Results: In 2019, PVF, SHF, and UFI reported 710.64 × 103, 335.25 × 103, and 2,133.88 × 103, respectively, incident cases worldwide. Their ASR (/100,000 people-years) were 9.31, 4.05, and 28.07. During 1990-2019, the overall incident ASRs of PVF presented an increasing trend (EAPC = 0.61, 95% confidence interval [CI]: 0.48 to 0.75). Notably, pronounced increasing trends were observed in Tropical Latin America, and North Africa and Middle East. However, incident trends of SHF and UFI declined globally, with the respective EAPCs being -0.68 (95% CI: -0.83 to -0.54) and -0.98 (95% CI: -1.19 to -0.77). In 2019, the ASR of death due to PVF, SHF, and UFI were 2.23, 0.65, and 0.26, and that of DALYs were 127.56, 28.10, and 17.64, respectively. Decreasing trends in the ASRs of FV were observed in most regions and countries worldwide over the past three decades, particularly that of PVF in Estonia. Conclusion: The FV burden was heterogeneous across regions and countries, which was deeply subjected to socioeconomic factors. The findings highlighted that specific prevention strategies and interventions were required, particularly in the high prevalent settings.

Rotenone-Induced Neurodegeneration Is Enabled by a p38-Parkin-ROS Signaling Feedback Loop.

Rotenone, a component of pesticides, is widely used in agriculture and potentially causes Parkinson's disease (PD). However, the regulatory mechanisms of rotenone-induced PD are unclear. Here, we revealed a novel feedback mechanism of p38-Parkin-ROS regulating rotenone-induced PD. Rotenone treatment led to not only the activation of p38 but also Parkin inactivation and reactive oxygen species (ROS) overproduction in SN4741 cells. Meanwhile, p38 activation regulated Parkin phosphorylation at serine 131 to disrupt Parkin-mediated mitophagy. Notably, both p38 inhibition and Parkin overexpression decreased ROS levels. Additionally, the ROS inhibitor N-acetyl-l-cysteine (NAC) inhibited p38 and activated Parkin-mediated mitophagy. Both p38 inhibition and the ROS inhibitor NAC exerted a protective effect by restoring cell death and mitochondrial function in rotenone-induced PD models. Based on these results, the p38-Parkin-ROS signaling pathway is involved in neurodegeneration. This pathway represents a valuable treatment strategy for rotenone-induced PD, and our study provides basic research evidence for the safe use of rotenone in agriculture.

Hsp90 Inhibitor STA9090 Sensitizes Hepatocellular Carcinoma to Hyperthermia-Induced DNA Damage by Suppressing DNA-PKcs Protein Stability and mRNA Transcription.

As a conserved molecular chaperone, heat shock protein 90 (Hsp90) maintains the stability and homeostasis of oncoproteins and helps cancer cells survive. DNA-dependent protein kinase catalytic subunit (DNA-PKcs) plays a pivotal role in the non-homologous end joining pathway for DNA double-strand breaks (DSB) repair. Tumor cells contain higher levels of DNA-PKcs to survive by the hostile tumor microenvironment and various antitumor therapies. Here, we showed that increased levels of Hsp90α, Hsp90ß, and DNA-PKcs correlated with a poor overall survival in hepatocellular carcinoma (HCC). We revealed that Hsp90 N-terminal domain and C-terminal domain have different effects on DNA-PKcs protein and mRNA levels. The stability of DNA-PKcs depended on Hsp90α N-terminal nucleotide binding domain. Transcription factor SP1 regulates the transcription of PRKDC (gene name of DNA-PKcs) and is a client protein of Hsp90. Inhibition of Hsp90 N-terminal by STA9090 decreased the location of Hsp90α in nucleus, Hsp90α-SP1 interaction, SP1 level, and the binding of Hsp90α/SP1 at the proximal promoter region of PRKDC Because hyperthermia induces DSBs with increases level of DNA-PKcs, combined STA9090 treatment with hyperthermia effectively delayed the tumor growth and significantly decreased DNA-PKcs levels in xenografts model. Consistently, inhibition of Hsp90 increased the number of heat shock-induced γ-H2AX foci and delayed the repair of DSBs. Altogether, our results suggest that Hsp90 inhibitor STA9090 decreases DNA-PKcs protein stability and PRKDC mRNA level, which provide a theoretical basis for the promising combination therapy of hyperthermia and Hsp90 inhibitor in HCC.

Heat Shock Protein 90α-Dependent B-Cell-2-Associated Transcription Factor 1 Promotes Hepatocellular Carcinoma Proliferation by Regulating MYC Proto-Oncogene c-MYC mRNA Stability.

B-cell lymphoma 2 (Bcl-2)-associated transcription factor 1 (Bclaf1) is known to be involved in diverse biological processes, but, to date, there has been no evidence for any functional role of Bclaf1 in hepatocellular carcinoma (HCC) progression. Here, we demonstrate that Bclaf1 is frequently up-regulated in HCC and that Bclaf1 up-regulation is associated with Edmondson grade, lower overall survival rates, and poor prognosis. Overexpression of Bclaf1 in HCC cell lines HepG2 and Huh7 promoted proliferation considerably, whereas Bclaf1 knockdown had the opposite effect. Xenograft tumors grown from Bclaf1 knockdown Huh7 cells had smaller tumor volumes than tumors grown from control cells. Furthermore, our study describes MYC proto-oncogene (c-Myc) as a downstream target of Bclaf1, given that Bclaf1 regulates c-MYC expression posttranscriptionally by its RS domain. To exert this function, Bclaf1 must interact with the molecular chaperone, heat shock protein 90 alpha (Hsp90α). In HCC tissue samples, Hsp90α levels were also increased significantly and Hsp90α-Bclaf1 interaction was enhanced. Bclaf1 interacts with the C-terminal domain of Hsp90α, and this interaction is disrupted by the C-terminal domain inhibitor, novobiocin (NB), resulting in proteasome-dependent degradation of Bclaf1. Moreover, NB-induced disruption of Hsp90α-Bclaf1 interaction dampened the production of mature c-MYC mRNA and attenuated tumor cell growth in vitro and in vivo. Conclusion: Our findings suggest that Bclaf1 affects HCC progression by manipulating c-MYC mRNA stability and that the Hsp90α/Bclaf1/c-Myc axis might be a potential target for therapeutic intervention in HCC.

Bclaf1 promotes angiogenesis by regulating HIF-1α transcription in hepatocellular carcinoma.

The development of hepatocellular carcinomas (HCC) depends on their local microenvironment and the induction of neovascularization is a decisive step in tumor progression, since the growth of solid tumors is limited by nutrient and oxygen supply. Hypoxia is the critical factor that induces transcription of the hypoxia inducible factor-1α (HIF-1α) encoding gene HIF1A and HIF-1α protein accumulation to promote angiogenesis. However, the basis for the transcriptional regulation of HIF1A expression in HCC is still unclear. Here, we show that Bclaf1 levels are highly correlated with HIF-1α levels in HCC tissues, and that knockdown of Bclaf1 in HCC cell lines significantly reduces hypoxia-induced HIF1A expression. Furthermore, we found that Bclaf1 promotes HIF1A transcription via its bZIP domain, leading subsequently to increased transcription of the HIF-1α downstream targets VEGFA, TGFB, and EPO that in turn promote HCC-associated angiogenesis and thus survival and thriving of HCC cells. Moreover, we demonstrate that HIF-1α levels and microvessel density decrease after the shRNA-mediated Bclaf1 knockdown in xenograft tumors. Finally, we found that Bclaf1 levels increase in hypoxia in a HIF-1α dependent manner. Therefore, our study identifies Bclaf1 as a novel positive regulator of HIF-1α in the hypoxic microenvironment, providing new incentives for promoting Bcalf1 as a potential therapeutic target for an anti-HCC strategy.

Hyperthermia enhances 17-DMAG efficacy in hepatocellular carcinoma cells with aggravated DNA damage and impaired G2/M transition.

Due to the lack of effective treatment, hepatocellular carcinoma (HCC) is one of the malignancies with low survival rates worldwide. Combination of hyperthermia and chemotherapy has shown promising results in several abdominal tumours, but high expression of HSP90 in tumours attenuated the efficacy of hyperthermia. Thus a combination of hyperthermia and inhibition of HSP90 might be a feasible therapeutic strategy for HCC. One hepatic cell line (L02) and two HCC cell lines (Huh7 and HepG2) were heated at 42 °C for 0, 0.5 or 4 h with or without 100 nM 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG). HCC cells of the combination group exhibited more G2/M arrest and higher apoptotic rates which might result from suffering from more reactive oxygen species and serious DNA damage. Heat shock/17-DMAG co-treatment of HCC cells also destabilized CDK1, Cyclin B1 and CDC25C with a concomitant decreased proportion of cells in the M phase. Furthermore, co-treatment impaired the interaction of HSP90α with CDC37 and with CDK1, accompanied with decreased soluble CDK1. Combination of 17-DMAG with a 1.5-h whole body hyperthermia treatment attenuated tumour growth in xenograft mice models. These results suggest hyperthermia sensitize HCC to 17-DMAG, and combination of hyperthermia with 17-DMAG might be a potential therapeutic strategy for HCC.

Hypoxia attenuates Hsp90 inhibitor 17-DMAG-induced cyclin B1 accumulation in hepatocellular carcinoma cells.

Hypoxia stress plays a pivotal role in tumor formation, proliferation, and invasion. Conventional chemotherapy is less effective in the hypoxia microenvironment of solid tumor. Heat shock protein 90 (Hsp90) is an important molecular chaperone in cancer cells and has been a pharmaceutical target for decades. However, Hsp90 inhibitors demonstrate limited effect on solid tumor and the mechanism underlying is not clear. To determine whether hypoxia impairs the therapeutic effect of Hsp90 N-terminal inhibitor, 17-demethoxygeldanamycin hydrochloride (17-DMAG), in live cancer cells, we measured cell proliferation and cell cycle distribution. Cell proliferation assay indicates that hypoxia obviously promotes the proliferation of HepG2 and Huh7 cells after 24, 48, and 72 h and impairs 17-DMAG-induced G2/M arrest in liver cancer cells. As a client protein of Hsp90, cyclin B1 is critical for the transition from G2 to M phase and is related to the prognosis of the patients. We further checked the cyclin B1 messenger RNA (mRNA) level, protein level, ubiquitination of cyclin B1, nuclear translocation, and degradation of cyclin B1 affected by hypoxia after 17-DMAG treatment. The results demonstrate that hypoxia decreases the transcription of cyclin B1 and accelerates the ubiquitination, nuclear translocation, and degradation of cyclin B1. Taken together, our results suggest that hypoxia attenuates cyclin B1 accumulation induced by 17-DMAG and, hence, alleviates 17-DMAG-induced G2/M arrest.

Transurethral enucleation of the prostate versus transvesical open prostatectomy for large benign prostatic hyperplasia: a systematic review and meta-analysis of randomized controlled trials.

PURPOSE: To evaluate the efficacy and safety of transurethral enucleation of the prostate (TUEP) versus transvesical open prostatectomy (OP) for the management of large benign prostatic hyperplasia (BPH). METHODS: Randomized controlled trials (RCTs) comparing TUEP and OP were identified from PubMed, Embase and Web of Science up to February 28, 2015. A meta-analysis was conducted with the STATA 12.0 software. RESULTS: Nine RCTs including 758 patients were enrolled in our meta-analysis. There were no significant differences between the two groups in the maximum urinary flow rate at 1, 3, 6 months, 1 and 2 years: postvoiding residual urinary volume, prostate-specific antigen, international prostate symptom score and quality of life score at 1, 3, 6 months and 1 year; or international index of erectile function at 3, 6 months and 1 year. Perioperative outcomes including hemoglobin level drop, catheter period, irrigation length and hospital stay favored TUEP, while operative time and resected prostate weight favored OP. There was significantly less blood transfusion with TUEP, but no significant differences were found in other complications such as recatheterization, urinary tract infection, reintervention for clots and bleeding control, incidence of pneumonia and infarction, transient incontinence, bladder neck contracture, urethral stricture and recurrent adenoma. CONCLUSIONS: TUEP can be performed effectively and safely with functional outcomes and complications similar to OP for large BPH, whereas it has the advantages of a shorter catheter period, shorter hospital stays and less blood transfusion. These findings seem to support TUEP as the next-generation "gold standard" of surgery for large BPH.

Cytochrome P450 2E1 RsaI/PstI polymorphism is associated with urologic cancer risk: evidence from a meta-analysis.

Cytochrome P450 2E1 (CYP2E1) is involved in the metabolic activation of various carcinogens. CYP2E1 RsaI/PstI polymorphism has been identified in urologic cancer patients, while studies of the polymorphism have shown inconclusive trends in the risk of urologic cancers. Therefore, we performed this systematic review to provide a complete picture and conducted a meta-analysis to derive a precise estimation. We searched PubMed, Embase and Web of Science to identify eligible studies up to December 15, 2014. 12 studies with 2712 cases and 2977 controls were included in the meta-analysis.The odds ratio with a 95% confidence interval was used to assess the strength of associations. We observed that the c2 allele of CYP2E1 RsaI/PstI polymorphism was associated with a decreased risk of urologic cancer under all genetic models (c2 vs. c1: OR = 0.742, 95% CI = 0.659-0.835); c2c2 vs. c1c1: OR = 0.516, 95% CI = 0.357-0.745; c1c2 vs. c1c1: OR = 0.748, 95% CI = 0.748 (0.648-0.863; c2c2 + c1c2 vs. c1c1: OR = 0.722, 95% CI = 0.629-0.829; c2c2 vs. c1c1 + c1c2: OR = 0.578, 95% CI = 0.401-0.832). In the subgroup analysis by cancer type, statistically significant associations were found in urothelial cancer in all genetic models. When stratified by ethnicity, a same trend was also indicated in Asians in all genetic models.To conclude, our results support the conclusion that the CYP2E1 RsaI/PstI polymorphism may be associated with urologic cancer susceptibility. The c2 allele is a low-penetrance risk factor for urologic cancer development.