Epstein-Barr Virus Envelope Glycoprotein gp110 Inhibits IKKi-Mediated Activation of NF-κB and Promotes the Degradation of ß-Catenin.

Epstein-Barr virus (EBV) infects host cells and establishes a latent infection that requires evasion of host innate immunity. A variety of EBV-encoded proteins that manipulate the innate immune system have been reported, but whether other EBV proteins participate in this process is unclear. EBV-encoded envelope glycoprotein gp110 is a late protein involved in virus entry into target cells and enhancement of infectivity. Here, we reported that gp110 inhibits RIG-I-like receptor pathway-mediated promoter activity of interferon-ß (IFN-ß) as well as the transcription of downstream antiviral genes to promote viral proliferation. Mechanistically, gp110 interacts with the inhibitor of NF-κB kinase (IKKi) and restrains its K63-linked polyubiquitination, leading to attenuation of IKKi-mediated activation of NF-κB and repression of the phosphorylation and nuclear translocation of p65. Additionally, gp110 interacts with an important regulator of the Wnt signaling pathway, ß-catenin, and induces its K48-linked polyubiquitination degradation via the proteasome system, resulting in the suppression of ß-catenin-mediated IFN-ß production. Taken together, these results suggest that gp110 is a negative regulator of antiviral immunity, revealing a novel mechanism of EBV immune evasion during lytic infection. IMPORTANCE Epstein-Barr virus (EBV) is a ubiquitous pathogen that infects almost all human beings, and the persistence of EBV in the host is largely due to immune escape mediated by its encoded products. Thus, elucidation of EBV's immune escape mechanisms will provide a new direction for the design of novel antiviral strategies and vaccine development. Here, we report that EBV-encoded gp110 serves as a novel viral immune evasion factor, which inhibits RIG-I-like receptor pathway-mediated interferon-ß (IFN-ß) production. Furthermore, we found that gp110 targeted two key proteins, inhibitor of NF-κB kinase (IKKi) and ß-catenin, which mediate antiviral activity and the production of IFN-ß. gp110 inhibited K63-linked polyubiquitination of IKKi and induced ß-catenin degradation via the proteasome, resulting in decreased IFN-ß production. In summary, our data provide new insights into the EBV-mediated immune evasion surveillance strategy.

Poorly differentiated cluster grade-a vital predictor for lymph node metastasis and oncological outcomes in patients with T1 colorectal cancer: a retrospective study.

BACKGROUND: T1 colorectal cancers have a low lymph node metastasis rate and good prognosis. Thus, endoscopic resection is an attractive choice. This study aimed to describe the value of poorly differentiated cluster grade in identifying endoscopically curable T1 colorectal cancers. METHODS: We included 183 T1 colorectal cancer patients who underwent curative resection. Univariate and multivariate logistic regressions were used to identify lymph node metastasis predictors. The Akaike information criterion was used to determine whether poorly differentiated cluster grade was the best predictor. Backward regression was used to screen the variables. Survival analyses were conducted to determine the prognostic predictive power of poorly differentiated cluster grade. Correlations among predictors and concordance between our pathologists were also investigated. RESULTS: Poorly differentiated cluster grade was an independent predictor for lymph node metastasis (adjusted odds ratio [OR]G 3 = 0.001; 95% confidence interval [95% CI]G 3 = < 0.001, 0.139) in T1 colorectal cancer patients; moreover, it had the best predictive value (AIC = 61.626) among all indicators. It was also screened for inclusion in the predictive model. Accordingly, a high poorly differentiated cluster grade independently indicated shorter overall survival (hazard ratio [HR]G 2 = 4.315; 95% CIG 2 = 1.506, 12.568; HRG 3 = 5.049; 95% CIG 3 = 1.326, 19.222) and disease-free survival (HRG 3 = 6.621; 95% CIG 3 = 1.472, 29.786). CONCLUSIONS: Poorly differentiated cluster grade is a vital reference to manage T1 colorectal cancer. It could serve as an indicator to screen endoscopically curable T1 colorectal cancers.

Ni-Catalyzed Regioselective Hydroarylation of 1-Aryl-1,3-Butadienes with Aryl Halides.

An efficient nickel-catalyzed regioselective hydroarylation of 1,3-dienes with aryl halides and a silane has been developed, affording a range of allylic arenes in good to excellent yields under mild conditions. This method exhibits broad substrate scope, and excellent functional group tolerance. Late-stage modification of complex architectures was demonstrated.

Subcellular Localization of Epstein-Barr Virus BLLF2 and Its Underlying Mechanisms.

Epstein-Barr virus (EBV), the pathogen of several human malignancies, encodes many proteins required to be transported into the nucleus for viral DNA reproduction and nucleocapsids assembly in the lytic replication cycle. Here, fluorescence microscope, mutation analysis, interspecies heterokaryon assays, co-immunoprecipitation assay, RNA interference, and Western blot were performed to explore the nuclear import mechanism of EBV encoded BLLF2 protein. BLLF2 was shown to be a nucleocytoplasmic shuttling protein neither by a chromosomal region maintenance 1 (CRM1)- nor by a transporter associated with antigen processing (TAP)-dependent pathway. Yet, BLLF2's two functional nuclear localization signals (NLSs), NLS1 (16KRQALETVPHPQNRGR31) and NLS2 (44RRPRPPVAKRRRFPR58), were identified, whereas the predicted NES was nonfunctional. Finally, BLLF2 was proven to transport into the nucleus via a Ran-dependent and importin ß1-dependent pathway. This mechanism may contribute to a more extensive insight into the assembly and synthesis of EBV virions in the nucleus, thus affording a new direction for the treatment of viruses.

The Impact of Preoperative Sarcopenia on Survival Prognosis in Patients Receiving Neoadjuvant Therapy for Esophageal Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND: Sarcopenia is a poor prognostic factor in patients with esophageal cancer (EC). It can be aggravated by neoadjuvant therapy (NAT) that improves the prognosis of patients with EC. Until now, the impact of preoperative sarcopenia on survival prognosis in patients receiving NAT for EC remains unclear. METHODS: We systematically researched relevant studies in the PubMed, EMBASE, Web of Science, the Cochrane Library databases up to March 8, 2020. Prevalence of sarcopenia before and after NAT, overall survival (OS) and disease-free survival (DFS) were collected for analysis. Finally, eleven cohort studies were included. RESULTS: Pooled analysis indicated that preoperative sarcopenia was negatively associated with OS. (HR = 1.290; 95% CI [1.078-1.543]; P = 0.005; I 2 = 0.0%) and DFS (HR = 1.554; 95% CI [1.177-2.052]; P = 0.002; I 2 = 0.0%) in the patients with EC receiving NAT. The prevalence of sarcopenia increased by 15.4% following NAT (95%CI [12.9%-17.9%]). Further subgroup analysis indicated that sarcopenia diagnosed following NAT (HR = 1.359; 95% CI [1.036-1.739]; P = 0.015; I 2 = 6.9%) and age >65 years (HR = 1.381; 95% CI [1.090- 1.749]; P = 0.007; I 2 = 0.0%) were the independent risk factors for decreased OS. CONCLUSIONS: Clinicians should strengthen the screening of preoperative sarcopenia in patients of EC both receiving NAT and older than 65 years and give active nutritional support to improve the prognosis of patients. SYSTEMATIC REVIEW REGISTRATION: International Platform of Registered Systematic Review and Meta-Analysis Protocols (INPLASY), identifier INPLASY202050057.

Sini Decoction Ameliorates Colorectal Cancer and Modulates the Composition of Gut Microbiota in Mice.

Sini Decoction (SND), as a classic prescription of Traditional Chinese Medicine (TCM), has been proved to be clinically useful in cardiomyopathy and inflammatory bowel diseases. However, the role and mechanism of SND in colitis-associated cancer remains unclear. This study aims to evaluate the effect of SND on colorectal cancer(CRC) symptoms and further explore the changes of gut microbes mediated by SND extract in azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced CRC mice through 16 S rRNA sequencing. Our results indicated that treatment with SND extract could ameliorate the tumors' malignant degree by decreasing tumor number and size. Also, the expression levels of Cyclooxygenase 2 and Mucin-2, which are typical CRC biomarkers, were reduced compared to the CRC group. In the meantime, SND extract can upregulate CD8+ T lymphocytes' expression and Occludin in the colonic mucosal layer. Besides, SND inhibited the expression of CD4+ T cells and inflammatory cytokines in CRC tissue. According to bioinformatics analysis, SND extract was also suggested could modulate the gut microbial community. After the SND treatment, compared with the CRC mice model, the number of pathogenic bacteria showed a significant reduction, including Bacteroides fragilis and Sulphate-reducing bacteria; and SND increased the relative contents of the beneficial bacteria, including Lactobacillus, Bacillus coagulans, Akkermansia muciniphila, and Bifidobacterium. In summary, SND can effectively intervene in colorectal cancer development by regulating intestinal immunity, protecting the colonic mucosal barrier, and SND can change the intestinal microbiota composition in mice.

Mediastinal granular cell tumor diagnosed with endoscopic ultrasound-guided fine needle aspiration via a modified technique based on wet suction: A case report and literature review.

Granular cell tumor (GCT) represents a less frequently seen tumor originating from Schwann cells. Although GCT develops in various locations in the human body, GCT of the mediastinum is extremely uncommon. A case of mediastinal GCT diagnosed by aspiration using a fine needle assisted by endoscopic ultrasound (EUS-FNA) via a modified technique based on wet suction was reported. An asymptomatic 28-year-old man was referred for assessment of a mass in the mediastinum that was found incidentally via chest computed tomography (CT) at health screening. EUS demonstrated a hypoechoic lesion with a distinct boundary, which was derived from the upper posterior mediastinum and partly located close to the posterior wall of the esophagus. Therefore, EUS-FNA with a modified wet suction technique was performed to harvest adequate specimens for the diagnosis of GCT. Minimally invasive tumor removal was performed, and histological examination of the specimen harvested surgically verified GCT, consistent with histological findings of the specimen obtained by EUS-FNA. The case highlights that a good accuracy of histological diagnosis and specimen quality are achieved for the modified wet-suction technique in EUS-FNA, and a preoperative diagnosis of mediastinal GCT can be made with certainty.

Comprehensive Analysis Revealed that CDKN2A is a Biomarker for Immune Infiltrates in Multiple Cancers.

The CDKN2A (cyclin dependent kinase inhibitor 2A/multiple tumor suppressor 1) gene, also known as the P16 gene, encodes multiple tumor suppressor 1 (MTS1), which belongs to the INK4 family. In tumor tissue, CDKN2A has a high expression level compared with normal tissue and reflects prognosis in tumor patients. Our research targeted the analysis of CDKN2A expression in 33 tumors and clinical parameters, patient prognosis and tumor immunity roles. The CDKN2A expression level was significantly correlated with the tumor mutation burden (TMB) in 10 tumors, and the expression of CDKN2A was also correlated with MSI (microsatellite instability) in 10 tumors. CDKN2A expression was associated with infiltrating lymphocyte (TIL) levels in 22 pancancers, thus suggesting that CDKN2A expression is associated with tumor immunity. Enrichment analysis indicated that CDKN2A expression was involved in natural killer cell-mediated cytotoxicity pathways, antigen processing and presentation, olfactory transduction pathways, and regulation of the autophagy pathway in multiple cancers. CDKN2A was significantly associated with several immune cell infiltrates in pantumors. CDKN2A may serve as a promising prognostic biomarker and is associated with immune infiltrates across cancers.

Involvement of CYP2E1-ROS-CD36/DGAT2 axis in the pathogenesis of VPA-induced hepatic steatosis in vivo and in vitro.

Valproic acid (VPA) is a widely prescribed antiepileptic drug, which may cause steatosis in the liver. Oxidative stress is associated with the progression of VPA-induced hepatic steatosis. However, the potential mechanisms are not fully understood. In this study, we demonstrated the involvement of CYP2E1-ROS-CD36/DGAT2 axis in the pathogenesis of VPA-induced hepatic steatosis in vitro and in vivo. First, VPA treatment (500 mg/kg in mice, 5 mM in LO2 cells) induced hepatic steatosis and enhanced reactive oxidative stress (ROS) level, and ROS scavenger, N-acetyl-L-cysteine (NAC, 200 mg/kg in mice, 1 mM in LO2 cells) reversed the changes. Next, we observed the enhanced expression and enzymatic activity of cytochrome P450 2E1 (CYP2E1) in VPA-treated mice and LO2 cells. Importantly, VPA-induced ROS accumulation and hepatic steatosis were attenuated when CYP2E1 was inhibited using CYP2E1 inhibitor, diallyl sulfide (DAS, 100 mg/kg in mice, 1 mM in LO2 cells) or in CYP2E1-knockdown cell line, suggesting that CYP2E1 plays a potential role in ROS production following hepatic steatosis. Furthermore, gene expression analysis showed that the mRNA levels of cluster of differentiation 36 (CD36), a fatty acid translocase protein and distinct diacylglycerol acyltransferase 2 (DGAT2) were significantly upregulated in mice and LO2 cells after VPA treatment, while the change was alleviated by NAC and DAS. Meanwhile, time course experiments demonstrated that the increase of CYP2E1 level occurred earlier than that of ROS, CD36 and DGAT2, and ROS generation preceded the onset of hepatic steatosis. Taken together, VPA treatment enhances the expression and enzymatic activity of CYP2E1, which promotes ROS production and then causes CD36 and DGAT2 overproduction and hepatic steatosis in mice and LO2 cells, which provides a novel insight into VPA-induced hepatic steatosis.

The combination therapy of transarterial chemoembolisation and sorafenib is the preferred palliative treatment for advanced hepatocellular carcinoma patients: a meta-analysis.

BACKGROUND: To compare the efficacy of three types of palliative therapy for advanced hepatocellular carcinoma (HCC), including transarterial chemoembolisation (TACE) monotherapy, sorafenib alone and their combination. METHODS: The databases of PubMed, Embase and Cochrane Library were retrieved. The odds ratio (OR) with its 95% confidence interval (CI) was used to investigate the binary variables, and the standardised mean difference (SMD) with its 95% CI was employed to evaluate the continuous variables. All statistical tests were performed by using Stata/SE, version 12.0. RESULTS: Thirty-one clinical studies, containing 5125 unique cases of patients with advanced HCC, were included. There were significant improvements in overall survival (OS) (pooled SMD = 2.54; 95% CI 1.74-3.34) and time to progression (TTP) (pooled SMD = 2.49; 95% CI 0.87-4.12) of the patients after receiving the combination therapy of TACE and sorafenib, compared to TACE monotherapy, and the OS in the combined treatment cohort was also longer than that in the sorafenib-alone cohort (pooled SMD = 2.92; 95% CI 1.72-4.13). The combination therapy group in comparison to the TACE group benefited a significantly increased overall response rate (ORR) (pooled OR = 2.61; 95% CI 1.43-4.77), 1-year (pooled OR = 2.96; 95% CI 1.71-5.14) and 2-year (pooled OR = 1.64; 95% CI 1.18-2.28) survival rates and reduced disease progression rate (DPR) (pooled OR = 0.47; 95% CI 0.33-0.68); in parallel, the ORR in the group was also significantly higher than that in the sorafenib-alone group (pooled OR = 3.62; 95% CI 1.28-10.22), although without a difference in the DPR (pooled OR = 0.28; 95% CI 0.05-1.48). In addition, we discovered that the 1-year (pooled OR = 1.39; 95% CI 0.84-2.29) and 2-year (pooled OR = 1.70; 95% CI 0.69-4.18) survival rates in the TACE monotherapy cohort were not significantly different to those in the sorafenib-alone cohort. CONCLUSION: The combination therapy is more effective than monotherapy in improving the prognostic outcomes of patients with advanced HCC. Therefore, we recommend it as the preferred treatment intervention for those patients.

Herpes Simplex Virus 1 UL2 Inhibits the TNF-α-Mediated NF-κB Activity by Interacting With p65/p50.

Herpes simplex virus 1 (HSV-1) is a large double-stranded DNA virus that encodes at least 80 viral proteins, many of which are involved in the virus-host interaction and are beneficial to the viral survival and reproduction. However, the biological functions of some HSV-1-encoded proteins are not fully understood. Nuclear factor κB (NF-κB) activation is the major antiviral innate response, which can be triggered by various signals induced by cellular receptors from different pathways. Here, we demonstrated that HSV-1 UL2 protein could antagonize the tumor necrosis factor α (TNF-α)-mediated NF-κB activation. Co-immunoprecipitation assays showed that UL2 could interact with the NF-κB subunits p65 and p50, which also revealed the region of amino acids 9 to 17 of UL2 could suppress the NF-κB activation and interact with p65 and p50, and UL2 bound to the immunoglobulin-like plexin transcription factor functional domain of p65. However, UL2 did not affect the formation of p65/p50 dimerization and their nuclear localizations. Yet, UL2 was demonstrated to inhibit the NF-κB activity by attenuating TNF-α-induced p65 phosphorylation at Ser536 and therefore decreasing the expression of downstream inflammatory chemokine interleukin 8. Taken together, the attenuation of NF-κB activation by UL2 may contribute to the escape of host's antiviral innate immunity for HSV-1 during its infection.

Epstein-Barr Virus Early Protein BFRF1 Suppresses IFN-ß Activity by Inhibiting the Activation of IRF3.

Epstein-Barr virus (EBV) is the causative agent of infectious mononucleosis that is closely associated with several human malignant diseases, while type I interferon (IFN-I) plays an important role against EBV infection. As we all know, EBV can encode some proteins to inhibit the production of IFN-I, but it's not clear whether other proteins also take part in this progress. EBV early lytic protein BFRF1 is shown to be involved in viral maturation, however, whether BFRF1 participates in the host innate immune response is still not well known. In this study, we found BFRF1 could down-regulate sendai virus-induced IFN-ß promoter activity and mRNA expression of IFN-ß and ISG54 during BFRF1 plasmid transfection and EBV lytic infection, but BFRF1 could not affect the promoter activity of NF-κB or IRF7. Specifically, BFRF1 could co-localize and interact with IKKi. Although BFRF1 did not interfere the interaction between IKKi and IRF3, it could block the kinase activity of IKKi, which finally inhibited the phosphorylation, dimerization, and nuclear translocation of IRF3. Taken together, BFRF1 may play a critical role in disrupting the host innate immunity by suppressing IFN-ß activity during EBV lytic cycle.

Application of endoscopic submucosal dissection in duodenal space-occupying lesions.

BACKGROUND: Endoscopic submucosal dissection (ESD) has been advocated by digestive endoscopists because of its comparable therapeutic effect to surgery, reduced trauma, faster recovery, and fewer complications. However, ESD for lesions of the duodenum is more challenging than those occurring at other levels of the gastrointestinal tract due to the thin intestinal wall of the duodenum, narrow intestinal space, rich peripheral blood flow, proximity to vital organs, and high risks of critical adverse events including intraoperative and delayed bleeding and perforation. Because of the low prevalence of the disease and the high risks of severe adverse events, successful ESD for lesions of the duodenum has rarely been reported in recent years. AIM: To investigate the efficacy and safety of ESD in the treatment of duodenal space-occupying lesions. METHODS: Clinical data of 24 cases of duodenal lesions treated by ESD at the Digestive Endoscopy Center of the Affiliated Hospital of Qingdao University from January 2016 to December 2019 were retrospectively analyzed. RESULTS: All of the 24 cases from 23 patients underwent ESD treatment for duodenal space-occupying lesions under general anesthesia, including 15 male and 8 female patients, with a mean age of 58.5 (32.0-74.0) years. There were 12 lesions (50%) in the duodenal bulb, 9 (37.5%) in the descending part, and 3 (12.5%) in the ball-descending junction. The mean diameter of the lesion was 12.75 (range, 11-22) mm. Thirteen lesions originated from the mucosa, of which 4 were low-grade intraepithelial neoplasia, 3 were hyperplastic polyps, 2 were chronic mucositis, 2 were adenomatous hyperplasia, 1 was high-grade intraepithelial neoplasia, and 1 was tubular adenoma. Eleven lesions were in the submucosa, including 5 neuroendocrine neoplasms, 2 cases of ectopic pancreas, 1 stromal tumor, 1 leiomyoma, 1 submucosal duodenal adenoma, and 1 case of submucosal lymph follicular hyperplasia. The intraoperative perforation rate was 20.8% (5/24), including 4 submucosal protuberant lesions and 1 depressed lesion. The mean length of hospital stay was 5.7 (range, 3-10) d, and the average follow-up time was 25.8 (range, 3.0-50.0) mo. No residual disease or recurrence was found in all patients, and no complications, such as infection and stenosis, were found during the follow-up period. CONCLUSION: ESD is safe and effective in the treatment of duodenal lesions; however, the endoscopists should pay more attention to the preoperative preparation, intraoperative skills, and postoperative treatment.

Endoscopic Removal of Gastrointestinal Stromal Tumors in the Stomach: A Single-Center Experience.

BACKGROUND AND AIMS: Endoscopic removal of GISTs (gastrointestinal stromal tumors) is recently recognized, but less is known about its efficacy and safety. This study is aimed at assessing the feasibility, clinical efficacy, and safety of the endoscopic removal of gastric GISTs. PATIENTS AND METHODS: Endoscopic removal (ER) of GISTs was performed in 134 patients at our hospital between January 2015 and January 2019. The clinical features, surgical outcomes, complications, pathological diagnosis, and risk classification were evaluated retrospectively. RESULTS: ER was successful in 131 cases (98%), including 58 by ESD (endoscopic submucosal dissection), 43 by ESE (endoscopic submucosal excavation), 25 by EFTR (endoscopic full-thickness resection), and 5 by STER (submucosal tunneling endoscopic resection). In addition, GISTs of two cases were resected using LECS (laparoscopic and luminal endoscopic cooperative surgery) for the extraluminal and intraluminal growth pattern. The average tumor size was 1.89 ± 1.25 cm (range: 0.5-6.0 cm). Of these patients, 26 cases had a large tumor size (range: 2.0-6.0 cm), and endoscopic removal was successful in all of them. During the procedure, endoclips were used to close the perforation in all cases, without conversion to open surgery. The average length of hospital stay was 5.50 ± 2.15 days (range: 3-10 days). In the risk classification, 106 (79.7%) were of a very low risk, 25 (18.8%) of a low risk, and 2 (1.5%) of a moderate risk. The moderate-risk cases were treated with imatinib mesylate after ER. No recurrence or metastasis was observed during the follow-up period of 23 ± 8 months (range: 3-48 months). CONCLUSIONS: The endoscopic treatment is feasible, effective, and safe for gastric GISTs, and individualized choice of approaches is recommended for GISTs.

Impaired intestinal barrier function in a mouse model of hyperuricemia.

Previous studies have demonstrated the effects of hyperuricemia on the damage to target organs, including the kidneys, joints and the heart. However, it is unclear whether hyperuricemia results in damage to the intestines. The aim of the present study was to investigate intestinal barrier dysfunction in a mouse model of hyperuricemia constructed by knocking out the urate oxidase (Uox) gene. The morphology of the intestine was assessed via hematoxylin and eosin, and alcian blue staining. The serum and intestinal tissue levels of uric acid, tumor necrosis factor (TNF)­α and interleukin (IL)­6, in addition to the presence of uremic toxins in the serum, were assessed. The levels of diamine oxidase (DAO), D­lactate (D­LAC) and endotoxins in the serum, which are markers of the intestinal permeability, were measured using ELISA. The expression of the intestinal tight junction proteins zona occludens­1 (ZO­1) and occludin were detected by reverse transcription­quantitative polymerase chain reaction, western blotting and immunohistochemical analysis. The Uox­knockout mice spontaneously developed hyperuricemia. Histopathological analysis indicated notable intestinal defects including sparse villi, mucosal edema and a declining mucus layer in hyperuricemic mice. The expression levels of ZO­1 and occludin in the intestines were downregulated, and the serum levels of DAO, D­LAC and endotoxins were higher in the hyperuricemic mice, compared with control mice. The serum and intestinal tissue levels of IL­6 and TNF­α were significantly increased. Additionally, the expression levels of the serum uremic toxins, serum creatinine, blood urea nitrogen were significantly increased in hyperuricemic mice compared with the control mice, while only a marked increase in indoxyl sulfate (IS) and p­cresol sulfate was reported. Collectively, the results of the present study suggested that intestinal barrier dysfunction and subsequent enhanced intestinal permeability may occur as a result of hyperuricemia in mice. Furthermore, we proposed that the loss of intestinal epithelium barrier function may be associated with uric acid­induced inflammatory responses; however, further investigation is required.

Cucurbitacin B suppresses proliferation of pancreatic cancer cells by ceRNA: Effect of miR-146b-5p and lncRNA-AFAP1-AS1.

Cucurbitacin B (CuB) is a natural tetracyclic triterpene product that displays antitumor activity against a wide variety of cancers. In this study, we explored the antipancreatic cancer activity of CuB via the inhibition of expression of the cancer-related long noncoding RNA, actin filament-associated protein 1-antisense RNA 1 (AFAP1-AS1). CuB arrested pancreatic cancer (PC) cells in the G2/M cell cycle phase by suppressing the expression of AFAP1-AS1. Insights into the mechanisms of competing endogenous RNAs (ceRNAs) gained from bioinformatics analysis and luciferase activity assays showed that the epidermal growth factor receptor (EGFR) and AFAP1-AS1 directly compete for miR-146b-5p binding. CuB-induced high miR-146b-5p expression and inhibited the expression of AFAP1-AS1. In summary, reducing the expression of endogenous AFAP1-AS1 effectively increased the available concentration of miR-146b-5p in PC, whereas miR-146b-5p overexpression prevented the expression of endogenous AFAP1-AS1. In particular, we hypothesized that AFAP1-AS1 might act as a ceRNA, effectively becoming a sponge for miR-146b-5p, thereby activating the expression of the EGFR. Thus, CuB suppresses the proliferation, in vitro and in vivo, of PC cells through the ceRNA effect of AFAP1-AS1 on miR-146b-5p.

ETS-1 induces Sorafenib-resistance in hepatocellular carcinoma cells via regulating transcription factor activity of PXR.

Transcription factor E26 transformation specific sequence 1 (ETS-1) is a primary regulator in the metastasis of human cancer cells, especially hepatocellular carcinoma (HCC) cells; and it would affect the prognosis of HCC patients who received chemotherapies. However, the regulatory role of ETS-1 in the resistance of HCC cells to molecular-targeting agent remains poorly understood. In the present work, we demonstrate that high ETS-1 expression correlates with poor prognosis of advanced HCC patients received Sorafenib treatment. Mechanistically, ETS-1 binds to nuclear Pregnane X receptor (PXR) directly and enhances PXR's transcription factor activity, which further leads to the induction of the PXR's downstream multi-drug resistance related genes. Overexpression of ETS-1 accelerates the metabolic clearance of Sorafenib in HCC cells and leads to the better survival and faster migration of those cells. The therapeutic studies show that ETS-1 promotes the Sorafenib-resistance of HCC tumor models and ETS-1 blockade enhances the anti-tumor capacity of Sorafenib by decreasing PXR activation. Thus, our study suggests that ETS-1 could enhance the activation of PXR and be a potential therapeutic target for overcoming Sorafenib resistance in HCC treatment.

Population pharmacokinetics of valproic acid in epileptic children: Effects of clinical and genetic factors.

Valproic acid (VPA) is a first-line anti-epileptic drug that is used in the treatment of generalized and partial seizures. Gene variants had been proved to influence the pharmacokinetics (PK) of VPA and contribute to its inter-individual variability (IIV). The aim of this study was to systematically investigate the effects of candidate gene variants (CYPs, UGTs, ABC transporters, and nuclear receptors) on VPA PK in Chinese children with epilepsy. A total of 1065 VPA serum trough concentrations at steady state were collected from 264 epileptic pediatric patients aged 3 months to 16 years. The population pharmacokinetic (PPK) model was developed using a nonlinear mixed effects modelling (NONMEM) approach. For the final PPK model, the oral clearance (CL/F) of VPA was estimated to be 0.259 L/h with IIV of 13.3%. The estimates generated by NONMEM indicated that the VPA CL/F was significantly influenced by patient body weight (increased by an exponent of 0.662), co-administration with carbamazepine (increased CL/F by 22%), and daily dose of VPA (increased by an exponent of 0.22). CL/F in patients with the LEPR rs1137101 variant (668 AG and GG genotypes) was much lower than in patients with the AA genotype (17.8% and 22.6% lower, respectively). However, none of the CYPs or UGTs gene variants was found to influence the PK of VPA in this study. Evaluation by bootstrap and normalized prediction distribution error (NPDE) showed that the final model was stable. The predictive performance was evaluated by goodness-of-fit (GOF) plots and visual predictive checks (VPC), and the results indicated satisfactory precision. Our model suggests a correlation between VPA CL/F and LEPR rs1137101 variants, which might be beneficial in the context of individual dose optimization.

TAK1 inhibition by natural cyclopeptide RA-V promotes apoptosis and inhibits protective autophagy in Kras-dependent non-small-cell lung carcinoma cells.

TAK1 kinase is required for the survival of Kras-dependent non-small-cell lung carcinoma (NSCLC) cells. Here, we report that the inhibition of TAK1 by a small natural cyclopeptide (RA-V) can promote apoptosis and inhibit protective autophagy in Kras-dependent NSCLC cells. Using short hairpin RNAs to deplete K-Ras, we identified H441 and H358 cells as Kras-dependent NSCLC cells which require protective basal autophagy for cell viability. We found that RA-V could selectively kill and induce apoptosis in H441 and H358 cells but had little effect on A549 and H460 (Kras-independent) cells. Furthermore, RA-V could inhibit basal autophagy in H441 and H358 cells. Mechanistic studies further showed that RA-V inhibits the level of TAK1 phosphorylation by binding directly to TAK1, resulting in the inhibition of the autophagy-related TAK1-AMPK-mTOR pathway. In addition, we found that RA-V could inhibit TAK1-P70S6K interaction, which may also inhibit basal autophagy. Our study shows that RA-V acts as an inducer of apoptosis and inhibitor of autophagy via the inhibition of TAK1 and provides the first example of TAK1 inhibition as a potential therapeutic strategy to promote apoptosis and inhibit protective autophagy in Kras-dependent NSCLC.

CHK1 inhibition sensitizes pancreatic cancer cells to gemcitabine via promoting CDK-dependent DNA damage and ribonucleotide reductase downregulation.

Inhibition of checkpoint kinase 1 (CHK1) is a promising therapeutic strategy to increase the effectiveness of DNA-damaging drugs in pancreatic cancer. However, owing to the multiple roles of CHK1 in the DNA damage response (DDR) pathway, the molecular mechanism of chemosensitization by CHK1 inhibitors is not definitive. In the present study, we explored the antitumor mechanism of LY2603618, a specific CHK1 inhibitor, alone or in combination with gemcitabine in 5 pancreatic cancer cell lines. LY2603618 treatment of the pancreatic cancer cell lines resulted in growth inhibition, with IC50 values ranging from 0.89 to 2.75 µM, but limited cell death. Importantly, treatment of pancreatic cancer cell lines with LY2603618 reduced the levels of pCDC25C, pCDK1, and pCDK2, accompanied by DNA damage and RRM1/2 downregulation. Furthermore, LY2603618 synergized with gemcitabine treatment to induce growth inhibition and apoptosis in pancreatic cancer cells. Mechanistic investigations showed that gemcitabine sensitization by CHK1 inhibition was associated with CDK­dependent RRM1/2 downregulation and DNA damage enhancement. These findings provide a basis for further development of combining CHK1 inhibitors and gemcitabine to treat pancreatic cancer.