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Hepatocellular carcinoma (HCC) is one of the most malignant tumors in the world. Inadequate efficacy of 5-fluorouracil (5-FU) on HCC could be related to low expression of human organic anion transporter 2 (OAT2). However, the knowledge of downregulation of OAT2 in HCC remains limited. We explored the underlying mechanism focusing on protein expression regulation and attempted to design a strategy to sensitize HCC cells to 5-FU. In this study, we revealed that the 1 bp to 300 bp region of OAT2 mRNA 3′ untranslated region (UTR) reduced its protein expression and uptake activity in Li-7 and PLC/PRF/5 cells. Mechanistically, it was demonstrated that staphylococcal nuclease and Tudor domain containing 1 (SND1) bound at the 1 bp to 300 bp region of OAT2 mRNA 3′ UTR, leading to a decrease in OAT2 protein expression. Enrichment analysis results indicated reduction of OAT2 might be mediated by translational inhibition. Furthermore, the knockdown of SND1 upregulated OAT2 protein expression and uptake activity. Based on this, decreasing SND1 expression enhanced 5-FU-caused G1/S phase arrest in Li-7 and PLC/PRF/5 cells, resulting in suppression of cell proliferation. Additionally, the knockdown of SND1 augmented the inhibitory effect of 5-FU on PLC/PRF/5 xenograft tumor growth in vivo by increasing OAT2 protein expression and accumulation of 5-FU in the tumor. Collectively, a combination of inhibition of SND1 with 5-FU might be a potential strategy to sensitize HCC cells to 5-FU from the perspective of restoring OAT2 protein level.SIGNIFICANCE STATEMENTWe investigated the regulatory mechanism of OAT2 protein expression in HCC cells and designed a strategy to sensitize them to 5-FU (OAT2 substrate) via restoring OAT2 protein level. It found that SND1, an RNA binding protein, regulated OAT2 protein expression by interacting with OAT2 mRNA 3′ UTR 1-300 bp region. Through decreasing SND1, the antitumor effect of 5-FU on HCC was enhanced in vitro and in vivo, indicating that SND1 could be a potential target for sensitizing HCC cells to 5-FU.

Neural architecture search (NAS) adopts a search strategy to explore the predefined search space to find superior architecture with the minimum searching costs. Bayesian optimization (BO) and evolutionary algorithms (EA) are two commonly used search strategies, but they suffer from being computationally expensive, challenging to implement, and exhibiting inefficient exploration ability. In this article, we propose a neural predictor guided EA to enhance the exploration ability of EA for NAS (NPENAS) and design two kinds of neural predictors. The first predictor is a BO acquisition function for which we design a graph-based uncertainty estimation network as the surrogate model. The second predictor is a graph-based neural network that directly predicts the performance of the input neural architecture. The NPENAS using the two neural predictors are denoted as NPENAS-BO and NPENAS-NP, respectively. In addition, we introduce a new random architecture sampling method to overcome the drawbacks of the existing sampling method. Experimental results on five NAS search spaces indicate that NPENAS-BO and NPENAS-NP outperform most existing NAS algorithms, with NPENAS-NP achieving state-of-the-art performance on four of the five search spaces.

Hand-foot syndrome (HFS) is a major adverse reaction to capecitabine (CAP). The exact pathogenesis of this disease remains unclear. In this study, metabolomics combined with cell RNA sequencing was used to study the mechanisms of CAP-induced HFS. The murine model of HFS was constructed by intragastric administration of CAP or its metabolites. Quantitative reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assays were used to verify the mechanisms. Metabolomics showed the phosphatidylinositol signaling pathway and amino acid and fatty acid metabolism to be the major metabolic alterations related to the occurrence of HFS. Transcriptomics profiles further revealed that the cytokine–cytokine receptor interaction, IL17 signaling pathway, Toll-like receptor signaling pathway, arachidonic acid metabolism, MAPK signaling pathway, and JAK-STAT3 signaling pathway were the vital steps in skin toxicity induced by CAP or its metabolites. We also verified that the inflammation mechanisms were primarily mediated by the abnormal expression of interleukin (IL) 6 or IL8 and not exclusively by COX-2 overexpression. Finally, the P38 MAPK, NF-κB, and JAK-STAT3 signaling pathways, which mediate high levels of expression of IL6 or IL8, were identified as potential pathways underlying CAP-induced HFS.

ABSTRACTIntroductionMulti-drug resistance (MDR) is a hindrance toward the successful treatment of cancers. The primary mechanism that gives rise to acquired chemoresistance is the overexpression of adenosine triphosphate-binding cassette (ABC) transporters. The dysregulation of non-coding RNAs (ncRNAs) is a widely concerned reason contributing to this phenotype.Areas coveredIn this review, we describe the role of intracellular and exosomal ncRNAs including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) in ABC transporters-induced tumor MDR. Meanwhile, we will introduce the potential therapeutic strategies which reverse MDR in terms of reducing the expression of ABC transporters viatargeting ncRNAs, like nucleic acid delivery with nanoparticles as well as miRNAs-targeted small molecular compounds.Expert opinionThe dysregulated ncRNAs-mediated overexpression of ABC transporters in chemo-resistant cancer is not negligible. Finding out the underlying mechanism may provide a theoretical basis for clinical therapy of cancer MDR, and the emergence of new approaches for gene therapy targeting ncRNAs to suppress ABC transporters makes reversing cancer MDR possible despite its clinical application requires further investigations. Also, the discovered ncRNAs regulating ABC transporters in chemo-resistant cancers are just a tip of the iceberg of the genetic transcripts, especially for circRNAs, which justify more concern.Abbreviations:MDR, multi-drug resistance; ABC, adenosine triphosphate-binding cassette; NcRNAs, non-coding RNAs; MiRNAs, microRNAs; LncRNAs, long non-coding RNAs; CircRNAs, circular RNAs; CeRNAs, competing endogenous RNAs; 3′UTR, 3′-untranslated regions; SLC, solute carrier; ABCB1/MDR1, ABC subfamily B member 1; ABCG2/BCRP, ABC subfamily G member 2; ABCCs/MRPs, ABC subfamily C 1 to 12; DLL1: Delta-like protein 1; DTX, docetaxel; DOX/ADM/ADR, doxorubicin/adriamycin; PTX, paclitaxel; VBL, vinblastine; VCR, vincristine; MTX, methotrexate; CDDP/DDP, cisplatin/cis-diaminedichloroplatinum; OXA/L-OHP, oxaliplatin; TMZ, temozolomide; 5-FU, 5-fluorouracil; MTA, pemetrexed; NSCLC, non-small cell lung carcinoma; HCC, hepatocellular carcinoma; CRC, colorectal carcinoma; RB, retinoblastoma; RCC, renal cell carcinoma; OS, osteosarcoma; PDAC, pancreatic ductal adenocarcinoma; TNBC, triple-negative breast cancer.

ABSTRACTRenal cell carcinoma (RCC) is a common malignant tumour affecting the urinary system, and multidrug resistance is one of the major reasons why chemotherapy for this type of cancer often fails. Previous studies have shown that loss of the human organic cation transporter OCT2 is the main factor contributing to oxaliplatin resistance in RCC, and that DNA hypermethylation and histone methylation play important roles in the transcriptional repression of OCT2in RCC. In this study, we found that histone acetylation also regulates OCT2repression in RCC and elucidated the underlying mechanisms. In normal renal cells, HDAC7combines with MYCat the OCT2promoter, resulting in a decrease in free HDAC7, which in turn increases the levels of H3K18ac and H3K27ac at the OCT2promotor and activates OCT2expression. In RCC cells, however, the interaction between HDAC7and MYCdoes not occur, which leads a high abundance of HDAC7and low levels of H3K18ac and H3K27ac at the OCT2promoter, thereby resulting in the inhibition of OCT2transcription. We found that combined treatment using the DNA methylation inhibitor decitabine and the histone deacetylase inhibitor vorinostat significantly increased the expression of OCT2in RCC cell lines, which sensitized these cells to oxaliplatin. We accordingly propose that the combination of anticancer agents and epigenetic drugs can provide a novel chemotherapeutic regimen.

ABSTRACTSLC47A2encodes MATE 2-K in the kidney, which mediates the secretion of certain endogenous and exogenous compounds. SLC47A2was dramatically repressed in patients with renal cell carcinoma (RCC), and a lower level of SLC47A2might act as a negative prognostic marker, although the mechanism is not well understood. In this study, we aimed to investigate the mechanism viawhich SLC47A2is downregulated in RCC. Based on the annotation information of the SLC47A2locus available in the UCSC genome browser database, we identified a novel lncRNA, which is transcribed from the SLC47A2locus and named it SANT1. Overexpression and knock-down assays were performed to investigate the effects of SANT1 on cis-regulation of SLC47A2. We verified the direct binding between SANT1 and SFPQ/E2F1/HDAC1 using the cross-linking and immunoprecipitation (CLIP) assay. Chromatin immunoprecipitation was performed to confirm the molecular mechanism viawhich SANT1 activates the transcription of the SLC47A2coding region. We observed that SANT1 can cis-regulate its own genetic locus. In tumour-adjacent tissues, the SLC47A2locus highly expresses SANT1, which can remove the regulatory SFPQ/E2F1/HDAC1 suppressor complex from the promoter region, thereby significantly increasing the levels of the H3K27ac modification and RNAPII binding. Owing to a low SANT1 level, the binding of this inhibitory complex in the promoter region is upregulated in RCC, which results in silencing of the SLC47A2coding region. In conclusion, we identified a novel lncRNA and elucidated the mechanism viawhich it regulates SLC47A2expression in RCC.

Mandelic acid (MA) is generally used as a biomarker of the exposure of styrene, which is classified as a class of hazardous environmental pollutants, and also used as an important chiral intermediate in pharmaceutical industry. The previous studies have found the excretion of phenylglyoxylic acid (PGA) in human and rat, a metabolite of MA, was mainly from S-MA rather than R-MA. The metabolic mechanism, however, is not clear. In order to explore the possible metabolic mechanism, the enzyme types involved in the stereoselectivity metabolism of MA were firstly studied, and then human and rat long-chain 2-hydroxy-acid oxidase 2 (HAO2) were recombinantly expressed to study the metabolic profiles of S-MA and its analogues. The results indicated that HAO2 might catalyze the stereoselectivity metabolism of S-MA in rats. Human HAO2 (hHAO2) and rat HAO2 (rHAO2) isozymes β1and β2were successfully cloned and expressed with high purity and good enzyme activities. The enzyme kinetic profiles of these enzymes were different for S-MA and analogues. The order of catalytic efficiency for hHAO2 and rHAO2, however, was reverse. It might be relevance to the difference in active amino acid residues and loop 4 in human and rat L-2-hydroxy acid oxidase isozyme B crystal structures.

Ten-eleven translocation 1 (TET1) is a member of the DNA demethylase family that regulates the methylation level of the genome. Dysregulation of TET1 in renal cell carcinoma (RCC) may be associated with RCC progression, but the mechanism of TET1 down-regulation in RCC is not yet known. MiR-183-5p is up-regulated in various tumor tissues and acts as an oncogene. We used Transwell and wound healing assays to test cell invasion and migration. To investigate DNA methylation, we used dot blot, which indicates TET1 enzyme activity. We verified the binding of miR-183-5p and TET1 3′-UTR (untranslated region) using dual-luciferase reporter assay. Our study demonstrated, for the first time, that miR-183-5p can directly repress TET1 expression in RCC. We observed a significant decrease in TET1 expression in RCC specimens, as reported in the literature, and a significant decrease in the concentration of 5hmC in RCC. By aligning the microRNA with a database and using the luciferase reporter gene method, we found that miR-183-5p can inhibit luciferase activity by binding to 453-459 bp of TET1 3′-UTR, leading to inhibition of TET1 expression. Furthermore, down-regulation of TET1 inhibited miR-200c expression and promoted RCC cell invasion and migration. Our findings suggest that in RCC, increased expression of miR-183-5p inhibits the expression of TET1, which in turn inhibits the expression of miR-200c and E-cadherin, both of which are associated with cell adhesion. This leads to the promotion of cell invasion and migration.

Background: Tenofovir disoproxil fumarate (TDF) is an oral prodrug and a nucleotide analog used for treating human immunodeficiency virus (HIV) and hepatitis B virus (HBV). A growing subset of TDF-treated HIV(+) individuals experienced drug-associated acute renal failure, suggesting drug-related nephrotoxicity. Impurities in pharmaceutical drugs generally present a risk, and no obvious benefit. Method: In an effort to determine whether the impurities also contribute to the nephrotoxicity, seven impurities were isolated and identified by using nuclear magnetic resonance (NMR) and mass spectra (MS). Human renal organic anion transporter 1 (hOAT1) localized in the kidney was the major transporter of tenofovir and presumably mediates its accumulation in the renal proximal tubules. On the basis of the Guidance for Industry document published by the United States Food and Drug Administration (U. S. FDA), we conducted an uptake assay and performed inhibition analysis using the Madin-Darby canine kidney cells stably expressing human OAT1 (MDCK-hOAT1), before analyzing our data by liquid chromatography tandem mass spectrometry (LC-MS/MS). Results: The uptake of the newly detected impurity RS5 was significantly higher than that of TDF. The 3- (4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that RS5 was more cytotoxic than TDF. The structure-affinity relationships indicated that 9-methyl functioned as a detoxification group. Conclusion: Our findings provide useful information for understanding the structure and toxicity of TDF and its impurities, and for assessing the clinical applications of TDF.

•The fatty acid metabolism gene has certain DNA gene changes and copy number variations in breast cancer patients, indicating that the imbalance of fatty acid metabolism may also be one of the pathogenic factors of breast cancer.•FABP4 is a very potential biomarker of breast cancer, which may play a tumor inhibitory role in early cancer, but it may behave as a carcinogen over time.•3.The prognosis model constructed in this study has good predictive ability for patient prognosis and drug efficacy, and can be used as one of the reference for clinical decision-making.

Currently, virtual teams are being used exponentially in higher education and business because of the development of technologies and globalization. These teams have become an essential approach for collaborative learning as well as task completion. Team learning, especially in an online format, can be challenging due to lack of effective training, communication and assessment measures. This article will introduce strategies, including adding a module on team processes, using Google applications for communication, and evaluating collaborative learning processes in addition to the products. These strategies were found instrumental in cultivating virtual teams through this case study of an online graduate course, and they can be valuable to online learning instructional designers or instructors who are interested in applying virtual teams in experiential instructional process.

Minipigs represent a good animal model because of the physiologic and anatomic similarities they share with humans. Three cytochrome P450 (CYP) 3A isozymes, CYP3A22, CYP3A29, and CYP3A46, have recently been reported to be expressed in Bama minipigs, which have limited data relating to their metabolic characteristics. In the present study, Bama minipig CYP3A22, CYP3A29, and CYP3A46 were recombinantly expressed and their metabolic manners were compared with those of human CYP3A4 and CYP3A5 and also human and Bama minipig liver microsomes. The results indicated Bama minipigs and human CYP3A enzymes showed similar metabolic kinetics and metabolite profiles using testosterone, midazolam, and nifedipine as substrates. However, the differences in amino acid sequences change the elimination velocity and metabolic preference of CYP3A enzymes to their substrates. It was demonstrated that CYP3A29, CYP3A4, and CYP3A5 were the most active enzymes for all reactions, whereas CYP3A46 was the least active enzyme. Substrate-dependent metabolism characteristics between human and Bama minipig CYP3A isoenzymes exist.

Isoneochamaejasmin A (INCA), a biflavonoid, is one of main active ingredients in the dried root of Stellera chamaejasmeL., a widely used traditional Chinese medicine. In the present study, we identified the glucuronidation metabolite of INCA and characterized the UDP glucuronosyltransferases (UGTs) responsible for INCA glucuronidation. 7-O-glucuronide (M1) and 4′-O-glucuronide (M2) were identified by incubation of INCA with human liver microsomes (HLMs) in the presence of UDP glucuronic acid, and their structures were confirmed by high-resolution mass spectrometry and nuclear magnetic resonance analyses. Although INCA is a single enantiomer molecule, its M1 metabolite showed two equal-size peaks on a πNAP stationary phase but only one peak on a C18stationary phase, indicating that the 7-/7′′- and 4′-/4′′′-hydroxyl groups of INCA were in different spatial configurations relative to each other. Among the recombinant human UGT isoform test and correlation analysis, UGT1A1, UGT1A3, and UGT1A9 were found to mediate M1 formation, whereas only UGT1A3 mediated M2 formation. Kinetic studies showed obvious species differences between human, mouse, rat, dog, and pig liver microsomes. UGT1A1, HLMs, and human intestinal microsomes, but not human kidney microsomes, exhibited substrate inhibition for the formation of M1. UGT1A1-mediated formation of M1 showed a 6- and 11-fold higher Vmaxthan did UGT1A3- and UGT1A9-mediated formation of M1, respectively. The results of the relative activity factor assay showed that UGT1A1 contributed approximately 75% in the formation of M1. These findings collectively indicate that UGT1A1 is the major enzyme in the formation of M1, whereas UGT1A3 is the major enzyme in the formation of M2.

Bile acids, a series of amphiphilic molecules, can interact with several drug transporters and impact drug ADME. Organic anion transporter 2 (OAT2) is exclusively expressed in the liver and kidney. However, the interaction between bile acids and hOAT2 is unelucidated. In this study, we observed that chenodeoxycholic acid, deoxycholic acid, ursodeoxycholic acid, glycochenodeoxycholic acid (GCDCA), glycodeoxycholic acid, glycoursodeoxycholic acid (GUDCA), taurocholic acid (TCA), taurochenodeoxycholic acid (TCDCA), taurodeoxycholic acid, tauroursodeoxycholic acid could all inhibit uptake activity of hOAT2 while glycocholic acid (GCA) and cholic acid could not. Among them, TCDCA was the strongest inhibitor with IC50value of 23.01 ± 3.45 μM and GCDCA was the second with IC50value of 54.26 ± 5.47 μM. Meanwhile, GCA, GUDCA, TCA and TCDCA were identified as substrates of hOAT2. We further found that bile acid mixture (BA mix) could inhibit hOAT2-mediated uptake of cGMP, 5-fluorouracil, irinotecan and paclitaxel. BA mix could reduce the toxicity of paclitaxel to MDCK-hOAT2 cells. In addition, the uptake activity of three SNPs of hOAT2 (C329T, G571A, and G1514A) was all reduced. In conclusion, this study revealed bile acids could interact with hOAT2, providing new insight into the alteration of drug ADME and therapeutic effect mediated by hOAT2.

UDP-glucuronosyltransferases (UGTs) play important roles in the disposition of many drugs and xenobiotics. Herbal medicine, an important group of multicomponent therapeutics, is widely and increasingly used. Drug metabolism of herbal medicine mediated by cytochrome P450s has been extensively studied; however, herbal medicine metabolism mediated by UGTs has not been adequately investigated. Thus, it is necessary to evaluate current evidence on the glucuronidation of herbal medicines by UGTs. In this review, the research advances of the potential for commonly used herbal medicines as UGT substrate and modulator are summarized. In addition, the herb-drug interactions associated with UGTs are also discussed.

Introduction: Despite the proven efficacy of plant-based diets in the management of cardiometabolic diseases, most healthcare providers do not incorporate them into treatment plans.Objective: Conduct a post-hoc evaluation of a novel plant-based nutrition program in a large integrated health care system, including the impact on health care outcomes.Methods: A large integrated health care system launched an innovative 12-week plant-based nutrition program that included weekly nutrition education, peer mentoring, and support. Plasma cholesterol levels, hemoglobin A1C, blood pressure, body weight, and healthcare utilization parameters were measured before and after the program. The current study is a pre- and post-descriptive analysis of the health metrics of individuals who participated in the program and a matched comparison group.Results: A total of 408 patients, across a wide range of weight categories, demographics, and co-morbidities, participated in a plant-based nutrition program, and program completers experienced mean reductions in total and LDL plasma cholesterol levels of 11.0 and 8.1 mg/dL, respectively, as well as reductions in medication usage, office visits, and body weight.Conclusion: Implementation of a novel plant-based, nutrition program in a large integrated health care system was associated with improvements in health outcomes.

In this Letter, the quantum group structure of the q-deformed Virasoro algebra Virqwill be given.

Weakly supervised temporal action localization (WS-TAL) aims to simultaneously recognize and localize action instances of interest in untrimmed videos with the use of the video-level label only. Some works have demonstrated that pseudo labels play an important role for performance improvement in WS-TAL. Since pseudo labels are inevitably inaccurate, direct adoption of noisy labels can lead to inappropriate knowledge transfer. Although some previous studies have shown the benefits of using only "reliable" pseudo labels, performance improvement is still limited. In this work, we experimentally analyze how the noise in pseudo labels affects model performance within the self-distillation framework. Motivated by the finding that incorrect pseudo labels with large confidence scores have a significant impact on performance, we propose the overconfidence suppression (OCS) strategy to mitigate the effect of the overconfident pseudo labels, and thus prevent over-fitting of the student model. In addition, a simplified contrast learning method is utilized to fine-tune the feature representation by increasing the separation of the foreground and background snippets. Equipped with the proposed methods, the benefits of pseudo labels can be better exploited and allow the model to achieve state-of-the-art performance on THUMOS'14 and ActivityNet-1.2 benchmarks. [ABSTRACT FROM AUTHOR]