Splicing factor hnRNPA1 regulates alternative splicing of LOXL2 to enhance the production of LOXL2Δ13.

Lysyl oxidase-like 2 (LOXL2) is a member of the lysyl oxidase family and has the ability to catalyze the cross-linking of extracellular matrix collagen and elastin. High expression of LOXL2 is related to tumor cell proliferation, invasion, and metastasis. LOXL2 contains 14 exons. Previous studies have found that LOXL2 has abnormal alternative splicing and exon skipping in a variety of tissues and cells, resulting in a new alternatively spliced isoform denoted LOXL2Δ13. LOXL2Δ13 lacks LOXL2WT exon 13, but its encoded protein has greater ability to induce tumor cell proliferation, invasion, and metastasis. However, the molecular events that produce LOXL2Δ13 are still unclear. In this study, we found that overexpression of the splicing factor hnRNPA1 in cells can regulate the alternative splicing of LOXL2 and increase the expression of LOXL2Δ13. The exonic splicing silencer exists at the 3' splice site and 5' splice site of LOXL2 exon 13. HnRNPA1 can bind to the exonic splicing silencer and inhibit the inclusion of exon 13. The RRM domain of hnRNPA1 and phosphorylation of hnRNPA1 at S91 and S95 are important for the regulation of LOXL2 alternative splicing. These results show that hnRNPA1 is a splicing factor that enhances the production of LOXL2Δ13.

Antibody-Protein-Aptamer Electrochemical Biosensor based on Highly Efficient Proximity-Induced DNA Hybridization on Tetrahedral DNA Nanostructure for Sensitive Detection of Insulin-like Growth Factor-1.

Herein, an antibody-protein-aptamer electrochemical biosensor was designed by highly efficient proximity-induced DNA hybridization on a tetrahedral DNA nanostructure (TDN) for ultrasensitive detection of human insulin-like growth factor-1 (IGF-1). Impressively, the IGF-1 antibody immobilized on the top vertex of the TDN could effectively capture the target protein with less steric effect, and the ferrocene-labeled signal probe (SP) bound on the bottom vertex of the TDN was close to the electrode surface for generating a strong initial signal. In the presence of target protein IGF-1 and an aptamer strand, an antibody-protein-aptamer sandwich could be formed on the top vertex of TDN, which would trigger proximity-induced DNA hybridization to release the SP on the bottom vertex of TDN; therefore, the signal response would decrease dramatically, enhancing the sensitivity of the biosensor. As a result, the linear range of the proposed biosensor for target IGF-1 was 1 fM to 1 nM with the limit of detection down to 0.47 fM, which was much lower than that of the traditional TDN designs on electrochemical biosensors. Surprisingly, the use of this approach offered an innovative approach for the sensitive detection of biomarkers and illness diagnosis.

Efficacy and safety of Qingda granule versus valsartan capsule in Chinese grade 1 hypertensive patients with low-moderate risk: A randomized, double-blind, double dummy, non-inferiority, multi-center trial.

BACKGROUND: The efficacy and safety of Qingda granule (QDG) in managing blood pressure (BP) among grade 1 hypertensive patients with low-moderate risk remain uncertain. METHODS: In the randomized, double-blind, double dummy, non-inferiority and multicenter trial, 552 patients with grade 1 hypertension at low-moderate risk were assigned at a ratio of 1:1 to receive either QDG or valsartan for 4 weeks, followed up by a subsequent 4 weeks. RESULTS: Post-treatment, clinic systolic/diastolic BPs (SBP/DBP) were reduced by a mean change of 9.18/4.04 mm Hg in the QDG group and 9.85/5.05 mm Hg in the valsartan group (SBP P = 0.47, DBP P = 0.16). Similarly, 24-hour, daytime and nighttime BPs were proportional in both groups (P > 0.05) after 4 weeks treatment. After discontinuing medications for 4 weeks, the mean reduction of clinic SBP/DBP were 0.29/0.57 mm Hg in the QDG group compared to -1.59/-0.48 mm Hg in the valsartan group (SBP P = 0.04, DBP P = 0.04). Simultaneously, the 24-hour SBP/DBP were reduced by 0.9/0.31 mm Hg in the QDG group and -1.66/-1.08 mm Hg in the valsartan group (SBP P = 0.006, DBP P = 0.02). And similar results were observed regarding the outcomes of daytime and nighttime BPs. There was no difference in occurrence of adverse events between two groups (P > 0.05). CONCLUSION: QDG proves to be efficacious for grade 1 hypertension at a low-to-medium risk, even after discontinuation of the medication for 4 weeks. These findings provide a promising option for managing grade 1 hypertension and suggest the potential for maintaining stable BP through intermittent administration of QDG. TRIAL REGISTRATION: ChiCTR2000033890.

Quercetin protects against hypertensive renal injury by attenuating apoptosis: an integrated approach using network pharmacology and RNA-Seq.

Quercetin is kown for its antihypertensive effects. However, its role on hypertensive renal injury has not been fully eucidated. In this study, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) staining, and Annexin V staining were used to assess the pathological changes and cells apoptosis in the renal tissues of Ang II-infused mice and Ang II- stimulated renal tubular epithelial cell line (NRK-52E). A variety of technologies, including network pharmacology, RNA-sequencing, immunohistochemistry, and Western blotting were performed to investigate its underlying mechanisms. Network pharmacology analysis identified multiple potential candidate targets (including TP53, Bcl-2 and Bax) and enriched signaling pathways (including apoptosis and p53 signaling pathway). Quercetin treatment significantly alleviated the pathological changes in renal tissues of Ang II-infused mice and reversed 464 differentially expressed transcripts (DETs), as well as enriched several signaling pathways, including those related apoptosis and p53 pathway. Furthermore, quercetin treatment significantly inhibited the cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells. Additionally, quercetin treatment inhibited the upregulation of p53, Bax, cleaved-caspase-9, and cleaved-caspase-3 protein expression and the downregulation of Bcl-2 protein expression in both renal tissue of Ang II-infused mice and Ang II-stimulated NRK-52E cells. Moreover, the molecular docking results indicated a potential binding interaction between quercetin and TP53. Quercetin treatment significantly attenuated hypertensive renal injury and cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells, and by targeting p53 may be one of the potential underlying mechanisms.

Optical bistability in a heterodimer composed of a quantum dot and a metallic nanoshell.

We theoretically explore the conditions for generating optical bistability (OB) in a heterodimer comprised of a semiconductor quantum dot (SQD) and a metallic nanoshell (MNS). The MNS is made of a metallic nanosphere as a core and a dielectric material as a shell. For the specific hybrid system considered, the bistable effect appears only if the frequency of the pump field is equal to (or slightly less than) the exciton frequency for a proper shell thickness. Bistability phase diagrams, when plotted, show that the dipole-induced bistable region can be greatly broadened by changing the shell thickness of the MNS in a strong exciton-plasmon coupling regime. In particular, we demonstrate that the multipole polarization not only narrows the bistable zone but also enlarges the corresponding thresholds for a given intermediate scaled pumping intensity. On the other hand, when the SQD couples strongly with the MNS, the multipole polarization can also significantly broaden the bistable region and induce a great suppression of the FWM (four-wave mixing) signal for a fixed shell thickness. These interesting findings offer a fresh understanding of the bistability conditions in an SQD/MNS heterodimer, and may be useful in the fabrication of high-performance and low-threshold optical bistable nanodevices.

Prediction of the SF-6D utility score from Lung cancer FACT-L: a mapping study in China.

OBJECTIVE: To develop a mapping algorithm for generating the Short Form Six-Dimension (SF-6D) utility score based on the Functional Assessment of Cancer Therapy-Lung (FACT-L) of lung cancer patients. METHODS: Data were collected from 625 lung cancer patients in mainland China. The Spearman rank correlation coefficient and principal component analysis were used to evaluate the conceptual overlap between the FACT-L and SF-6D. Five model specifications and four statistical techniques were used to derive mapping algorithms, including ordinary least squares (OLS), Tobit and beta-mixture regression models, which were used to directly estimate health utility, and ordered probit regression was used to predict the response level. The prediction performance was evaluated using the correlations between the root mean square error (RMSE), mean absolute error (MAE), concordance correlation coefficient (CCC), Akaike information criterion (AIC) and Bayesian information criterion (BIC) and the observed and predicted SF-6D scores. A five-fold cross-validation method was used to test the universality of each model and select the best model. RESULTS: The average FACT-L score was 103.024. The average SF-6D score was 0.774. A strong correlation was found between FACT-L and SF-6D scores (ρ = 0.797). The ordered probit regression model with the total score of each dimension and its square term, as well as age and sex as covariates, was most suitable for mapping FACT-L to SF-6D scores (5-fold cross-validation: RMSE = 0.0854; MAE = 0.0655; CCC = 0.8197; AEs > 0.1 (%) = 53.44; AEs > 0.05 (%) = 21.76), followed by beta-mixture regression for direct mapping. The Bland‒Altman plots showed that the ordered probit regression M5 had the lowest proportion of prediction scores outside the 95% agreement limit (-0.166, 0.163) at 4.96%. CONCLUSIONS: The algorithm reported in this paper enables lung cancer data from the FACT-L to be mapped to the utility of the SF-6D. The algorithm allows the calculation of quality-adjusted life years for cost-utility analyses of lung cancer.

Discovery of carbamate-based N-salicyloyl tryptamine derivatives as novel pleiotropic agents for the treatment of Alzheimer's disease.

In this work, based on the potential anti-AD molecule previously studied by our group, we continue to introduce different substituents at different positions to improve both drug-like properties and on target activities. 33 N-salicyloyl tryptamine-carbamate hybrids were designed, synthesized and evaluated as cholinesterase inhibitors. H327 was the most potent BChE inhibitor (eqBChE IC50 = 0.057 ± 0.005 µM), and showed threefold improved inhibitory potency than the positive drug rivastigmine (eqBChE IC50 = 0.19 ± 0.001 µM). In addition, H327 as a pseudo-irreversible BChE inhibitor was endowed with neuroprotective, antioxidative and anti-neuroinflammatory properties. Cytotoxicity and acute toxicity tests confirmed the safety of compound H327. The pharmacokinetics study showed that compound H327 had a longer T1/2 time and higher bioavailability than the lead compound 1 g. Compound H327 was able to cross the blood-brain barrier (BBB) in vivo. Moreover, the behavioral tests showed that compound H327 could significantly improve scopolamine-induced cognitive impairment in vivo. Overall, these results demonstrated that compound H327 is a promising multi-target agent for the treatment of AD.

Verbascoside enhances radiosensitivity of hepatocellular carcinoma cells through regulating miR-101-3p/Wee1 axis.

Verbascoside is a kind of phenylpropanoid glycoside derived from multiple medicinal plants, exerting anti-tumor effects in diverse human malignancies. However, the function of Verbascoside on the radiosensitivity of hepatocellular carcinoma (HCC) cells remains unknown. Human Huh7 and HepG2 cell lines were treated with Verbascosideis, and cell viability was detected with cell counting kit-8 (CCK-8) assay. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to detect miR-101-3p expression, and Western blot was used to quantify the expression of WEE1 G2 checkpoint kinase (WEE1). Then, CCK-8 and flow cytometry assays were used to detect the proliferation and apoptosis of HCC cells after Verbascoside and X-ray combined treatment, and the expressions of WEE1 and apoptosis-related proteins Bax and Bcl-2 were detected by Western blot. Verbascoside could improve the radiosensitivity of HCC cells in a dose-dependent manner. Verbascoside increased the expression of miR-101-3p but reduced WEE1 expression in HCC cells. Additionally, WEE1 was identified as a target of miR-101-3p. MiR-101-3p inhibition or WEE1 overexpression could reverse the effect of Verbascoside on the viability and apoptosis of HCC cells. Verbascoside increases the radiosensitivity of hepatocellular carcinoma cells via modulating miR-101-3p/WEE1 axis.

Promotion of rs3746804 (p. L267P) polymorphism to intracellular SLC52A3a trafficking and riboflavin transportation in esophageal cancer cells.

Riboflavin is an essential micronutrient for normal cellular growth and function. Lack of dietary riboflavin is associated with an increased risk for esophageal squamous cell carcinoma (ESCC). Previous studies have identified that the human riboflavin transporter SLC52A3a isoform (encoded by SLC52A3) plays a prominent role in esophageal cancer cell riboflavin transportation. Furthermore, SLC52A3 gene single nucleotide polymorphisms rs3746804 (T>C, L267P) and rs3746803 (C >T, T278M) are associated with ESCC risk. However, whether SLC52A3a (p.L267P) and (p.T278M) act in riboflavin transportation in esophageal cancer cell remains inconclusive. Here, we constructed the full-length SLC52A3a protein fused to green fluorescent protein (GFP-SLC52A3a-WT and mutants L267P, T278M, and L267P/T278M). It was confirmed by immunofluorescence-based confocal microscopy that SLC52A3a-WT, L267P, T278M, and L267P/T278M expressed in cell membrane, as well as in a variety of intracellular punctate structures. The live cell confocal imaging showed that SLC52A3a-L267P and L267P/T278M increased the intracellular trafficking of SLC52A3a in ESCC cells. Fluorescence recovery after photobleaching of GFP-tagged SLC52A3a meant that intracellular trafficking of SLC52A3a-L267P and L267P/T278M was rapid dynamics process, leading to its stronger ability to transport riboflavin. Taken together, the above results indicated that the rs3746804 (p.L267P) polymorphism promoted intracellular trafficking of SLC52A3a and riboflavin transportation in ESCC cells.

Dietary riboflavin deficiency induces ariboflavinosis and esophageal epithelial atrophy in association with modification of gut microbiota in rats.

PURPOSE: Riboflavin deficiency causes ariboflavinosis, a common nutritional deficiency disease. The purpose of this study is to investigate the effects of riboflavin deficiency on the important internal organs and its potential mechanisms. METHODS: Experiment 1, male F344 rats were randomly assigned to R6 (normal riboflavin, 6 mg/kg) and R0 (riboflavin-deficient, 0 mg/kg) groups. Experiment 2 rats were assigned to R6, R0.6 (0.6 mg/kg) and R0.06 (0.06 mg/kg) groups. Experiment 3 rats were assigned to R6 and R0 → R6 (riboflavin replenishment) groups. Bacterial communities were analyzed based on 16S rRNA gene sequencing. RESULTS: Riboflavin deficiency induced ariboflavinosis (R0.06 46.7%; R0 72%) and esophageal epithelial atrophy (R0.06 40%; R0 44%) in rats, while the R6 group did not display symptoms (P < 0.001, respectively). Esophageal epithelial atrophy occurred simultaneously (R0.06 66.7%; R0 63.6%) with ariboflavinosis or appeared alone (R0.06 33.3%; R0 36.4%). Esophagus is the most vulnerable internal organ. Riboflavin deficiency followed by replenishment (R0 → R6) was effective in treating ariboflavinosis (83.3% vs. 0%, P < 0.001) and esophageal epithelial atrophy (66.7% vs. 20%, P = 0.17). Riboflavin deficiency modulated gut microbiota composition. The several key genera (Romboutsia, Turicibacter and Clostridium sensu stricto 1) were strongly correlated with ariboflavinosis and esophageal epithelial atrophy (P < 0.01 or P < 0.05). The potential mechanism is that gut microbiota affects body's xenobiotic biodegradation and metabolism, and genomic instability. CONCLUSIONS: Riboflavin deficiency induces ariboflavinosis and esophageal epithelial atrophy by modulating the gut microbiota, and offers new Queryinsight into riboflavin deficiency and esophageal lesions.

Super-Enhancer-Driven Long Non-Coding RNA LINC01503, Regulated by TP63, Is Over-Expressed and Oncogenic in Squamous Cell Carcinoma.

BACKGROUND & AIMS: Long non-coding RNAs (lncRNAs) are expressed in tissue-specific pattern, but it is not clear how these are regulated. We aimed to identify squamous cell carcinoma (SCC)-specific lncRNAs and investigate mechanisms that control their expression and function. METHODS: We studied expression patterns and functions of 4 SCC-specific lncRNAs. We obtained 113 esophageal SCC (ESCC) and matched non-tumor esophageal tissues from a hospital in Shantou City, China, and performed quantitative reverse transcription polymerase chain reaction assays to measure expression levels of LINC01503. We collected clinical data from patients and compared expression levels with survival times. LINC01503 was knocked down using small interfering RNAs and oligonucleotides in TE7, TE5, and KYSE510 cell lines and overexpressed in KYSE30 cells. Cells were analyzed by chromatin immunoprecipitation sequencing, luciferase reporter assays, colony formation, migration and invasion, and mass spectrometry analyses. Cells were injected into nude mice and growth of xenograft tumors was measured. LINC01503 interaction with proteins was studied using fluorescence in situ hybridization, RNA pulldown, and RNA immunoprecipitation analyses. RESULTS: We identified a lncRNA, LINC01503, which is regulated by a super enhancer and is expressed at significantly higher levels in esophageal and head and neck SCCs than in non-tumor tissues. High levels in SCCs correlated with shorter survival times of patients. The transcription factor TP63 bound to the super enhancer at the LINC01503 locus and activated its transcription. Expression of LINC01503 in ESCC cell lines increased their proliferation, colony formation, migration, and invasion. Knockdown of LINC01503 in SCC cells reduced their proliferation, colony formation, migration, and invasion, and the growth of xenograft tumors in nude mice. Expression of LINC01503 in ESCC cell lines reduced ERK2 dephosphorylation by DUSP6, leading to activation of ERK signaling via MAPK. LINC01503 disrupted the interaction between EBP1 and the p85 subunit of PI3K, increasing AKT signaling. CONCLUSIONS: We identified an lncRNA, LINC01503, which is increased in SCC cells compared with non-tumor cells. Increased expression of LINC01503 promotes ESCC cell proliferation, migration, invasion, and growth of xenograft tumors. It might be developed as a biomarker of aggressive SCCs in patients.

ZEB1 mediates doxorubicin (Dox) resistance and mesenchymal characteristics of hepatocarcinoma cells.

The acquired chemoresistance during long term chemotherapy is one of the most important factors to limit the application of Doxorubicin (Dox) on clinical treatment of hepatocellular carcinoma (HCC) patients. Our present study found that Dox resistant HCC (HCC/Dox) cells had greater capability of in vitro migration and invasion compared to their parental cells. HCC/Dox cells exhibited mesenchymal characteristics, which was evidenced by the up regulation of fibronectin, vimentin while down regulation of E-Cadherin. Zeb1, one powerful epithelial mesenchymal transition related transcription factor (EMT-TF), was markedly upregulated in HCC/Dox cells. Targeted inhibition of Zeb1 via siRNA can suppress the cell migration and re-sensitized cells to Dox treatment. The upregulation of Zeb1 in HCC/Dox cells was due to the increasing protein and mRNA stability of Zeb1. In HCC/Dox cells, the down regulation of SIAH1 mediated the upregulation of protein stability of Zeb1, while decreased levels of miR-3129-5p was responsible for the increasing mRNA stability of Zeb1. Collectively, our data suggested that SIAH1 and miR-3129-5p induced upregulation of Zeb1 mediated the Dox resistance of HCC cells. Targeted inhibition of Zeb1 might be helpful to overcome of Dox resistance of HCC.

DWI and T2-Weighted MRI Volumetry in Resectable Rectal Cancer: Correlation With Lymphovascular Invasion and Lymph Node Metastases.

OBJECTIVE. The purpose of this study was to assess whether MR volumetric data on DW and T2-weighted MR images are correlated with lymphovascular invasion and lymph node metastases in resectable rectal cancer. MATERIALS AND METHODS. This retrospective study consisted of 50 consecutive patients with rectal cancer who underwent radical surgery within 1 week of MRI. The gross tumor volume was determined on both diffusion-weighted and T2-weighted MR images and correlated with pathologic lymphovascular invasion and lymph node metastases using univariate, multivariate, and ROC curve analyses. RESULTS. Both gross tumor volume values showed correlations with lymphovascular invasion (r = 0.750 vs r = 0.710; p < 0.0001) and lymph node metastases (r = 0.780 vs r = 0.755; p < 0.0001). Both values were associated with lymphovascular invasion and lymph node metastases in univariate analysis (all p < 0.0001), whereas only the DWI-based value was an independent risk factor for lymphovascular invasion (odds ratio = 1.207; p = 0.005) and lymph node metastases (odds ratio = 1.420; p = 0.005) in multivariate analysis. Both values could distinguish between N0 and N1, N0 and N1-N2, and N0-N1 and N2 disease (all p < 0.0001) in the Mann-Whitney U test. The area under the ROC curve was higher for the DWI-based value in lymphovascular invasion (0.899 vs 0.877), N0 vs N1 (0.865 vs 0.827), N0 vs N1-N2 (0.934 vs 0.911), and N0-N1 vs N2 (0.932 vs 0.927). CONCLUSION. Tumor volumetry data correlated with both lymphovascular invasion and lymph node metastases in resectable rectal cancer. In particular, the DWI-based gross tumor volume showed the most potential for noninvasive preoperative evaluation of lymphovascular invasion and lymph node metastases.

Correction to: Highly sensitive and robust peroxidase-like activity of Au-Pt core/shell nanorod-antigen conjugates for measles virus diagnosis.

After publication of the original article [1], an error was noted in the author affiliation. Lin Long is also affiliated to the College of Opto-electronic Engineering, Zaozhuang University, Zaozhuang, China, which is her first affiliation.

SLC52A3 expression is activated by NF-κB p65/Rel-B and serves as a prognostic biomarker in esophageal cancer.

The human riboflavin transporter-3 (encoded by SLC52A3) plays a prominent role in riboflavin absorption. Interestingly, abnormal expression patterns of SLC52A3 in multiple types of human cancers have been recently noted. However, the molecular mechanisms underlying its dysregulation remain unclear. In this study, we find that SLC52A3 has two transcript variants that differ in the transcriptional start site, and encode different proteins: SLC52A3a and SLC52A3b. Importantly, aberrant expressions of SLC52A3 are associated with stepwise development of esophageal squamous cell carcinoma (ESCC) as well as the survival rates of ESCC patients. Functionally, SLC52A3a, but not SLC52A3b, strongly promotes the proliferation and colony formation of ESCC cells. Furthermore, SLC52A3 5'-flanking regions contain NF-κB p65/Rel-B-binding sites, which are crucial for mediating SLC52A3 transcriptional activity in ESCC cells. Chromatin immunoprecipitation and electrophoretic mobility shift assay reveal that p65/Rel-B bind to 5'-flanking regions of SLC52A3. Accordingly, NF-κB signaling upregulates SLC52A3 transcription upon TNFα stimulation. Taken together, these results elucidate the mechanisms underlying SLC52A3 overexpression in ESCC. More importantly, our findings identify SLC52A3 as both a predictive and prognostic biomarker for this deadly cancer.

Low Intensity Pulsed Ultrasound Prevents Recurrent Ischemic Stroke in a Cerebral Ischemia/Reperfusion Injury Mouse Model via Brain-derived Neurotrophic Factor Induction.

The incidence of stroke recurrence is still higher despite the advanced progression of therapeutic treatment and medical technology. Low intensity pulsed ultrasound (LIPUS) has been demonstrated to possess therapeutic effects on neuronal diseases and stroke via brain-derived neurotrophic factor (BDNF) induction. In this study, we hypothesized that LIPUS treatment possessed therapeutic benefits for the improvement of stroke recurrence. Adult male C57BL/6J mice were subjected to a middle cerebral artery occlusion (MCAO) surgery and then followed to secondary MCAO surgery as a stroke recurrence occurred after nine days from the first MCAO. LIPUS was administered continuously for nine days before secondary MCAO. LIPUS treatment not only decreased the mortality but also significantly moderated neuronal function injury including neurological score, motor activity, and brain pathological score in the recurrent stroke mice. Furthermore, the administration of LIPUS attenuated the apoptotic neuronal cells and increased Bax/Bcl-2 protein expression ratio and accelerated the expression of BDNF in the brain of the recurrent stroke mice. Taken together, these results demonstrate for the first time that LIPUS treatment arouses the expression of BDNF and possesses a therapeutic benefit for the improvement of stroke recurrence in a mouse model. The neuroprotective potential of LIPUS may provide a useful strategy for the prevention of a recurrent stroke.

Riboflavin Depletion Promotes Tumorigenesis in HEK293T and NIH3T3 Cells by Sustaining Cell Proliferation and Regulating Cell Cycle-Related Gene Transcription.

Background: Riboflavin is an essential component of the human diet and its derivative cofactors play an established role in oxidative metabolism. Riboflavin deficiency has been linked with various human diseases. Objective: The objective of this study was to identify whether riboflavin depletion promotes tumorigenesis. Methods: HEK293T and NIH3T3 cells were cultured in riboflavin-deficient or riboflavin-sufficient medium and passaged every 48 h. Cells were collected every 5 generations and plate colony formation assays were performed to observe cell proliferation. Subcutaneous tumorigenicity assays in NU/NU mice were used to observe tumorigenicity of riboflavin-depleted HEK293T cells. Mechanistically, gene expression profiling and gene ontology analysis were used to identify abnormally expressed genes induced by riboflavin depletion. Western blot analyses, cell cycle analyses, and chromatin immunoprecipitation were used to validate the expression of cell cycle-related genes. Results: Plate colony formation of NIH3T3 and HEK293T cell lines was enhanced >2-fold when cultured in riboflavin-deficient medium for 10-20 generations. Moreover, we observed enhanced subcutaneous tumorigenicity in NU/NU mice following injection of riboflavin-depleted compared with normal HEK293T cells (55.6% compared with 0.0% tumor formation, respectively). Gene expression profiling and gene ontology analysis revealed that riboflavin depletion induced the expression of cell cycle-related genes. Validation experiments also found that riboflavin depletion decreased p21 and p27 protein levels by ∼20%, and increased cell cycle-related and expression-elevated protein in tumor (CREPT) protein expression >2-fold, resulting in cyclin D1 and CDK4 levels being increased ∼1.5-fold, and cell cycle acceleration. We also observed that riboflavin depletion decreased intracellular riboflavin levels by 20% and upregulated expression of riboflavin transporter genes, particularly SLC52A3, and that the changes in CREPT and SLC52A3 correlated with specific epigenetic changes in their promoters in riboflavin-depleted HEK293T cells. Conclusion: Riboflavin depletion contributes to HEK293T and NIH3T3 cell tumorigenesis and may be a risk factor for tumor development.

A Protocol for the Synthesis of CF2H-Containing Pyrazolo[1,5- c]quinazolines from 3-Ylideneoxindoles and in Situ Generated CF2HCHN2.

Herein is disclosed a selective and facile approach for the construction of CF2H-containing pyrazolo[1,5- c]quinazolines from easily accessible 3-ylideneoxindoles and in situ generated CF2HCHN2. The reaction involving a [3 + 2] cycloaddition/1,3-H shift/rearrangement/dehydrogenation cascade proceeded smoothly at room temperature in the absence of catalyst and additive. Moreover, this metal-free process along with mild conditions is desirable and valuable for the pharmaceutical industry. Importantly, this reaction features a broad substrate scope, good functional group tolerance, and gram-scale synthesis.

Highly sensitive and robust peroxidase-like activity of Au-Pt core/shell nanorod-antigen conjugates for measles virus diagnosis.

BACKGROUND: As a promising candidate for artificial enzymes, catalytically active nanomaterials show several advantages over natural enzymes, such as controlled synthesis at low cost, tunability of catalytic activities, and high stability under stringent conditions. Rod-shaped Au-Pt core/shell nanoparticles (Au@Pt NRs), prepared by Au nanorod-mediated growth, exhibit peroxidase-like activities and could serve as an inexpensive replacement for horseradish peroxidase, with potential applications in various bio-detections. The determination of measles virus is accomplished by a capture-enzyme-linked immunosorbent assay (ELISA) using Au@Pt NR-antigen conjugates. RESULTS: Based on the enhanced catalytic properties of this nanozyme probe, a linear response was observed up to 10 ng/mL measles IgM antibodies in human serum, which is 1000 times more sensitive than commercial ELISA. CONCLUSIONS: Hence, these findings provide positive proof of concept for the potential of Au@Pt NR-antigen conjugates in the development of colorimetric biosensors that are simple, robust, and cost-effective.