Cetuximab plus FOLFOXIRI versus cetuximab plus FOLFOX as conversion regimen in RAS/BRAF wild-type patients with initially unresectable colorectal liver metastases (TRICE trial): A randomized controlled trial.

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.

Construction of CDKN2A-related competitive endogenous RNA network and identification of GAS5 as a prognostic indicator for hepatocellular carcinoma.

BACKGROUND: Competitive endogenous RNA (ceRNA) is an innovative way of gene expression modulation, which plays a crucial part in neoplasia. However, the intricacy and behavioral characteristics of the ceRNA network in hepatocellular carcinoma (HCC) remain dismal. AIM: To establish a cyclin dependent kinase inhibitor 2A (CDKN2A)-related ceRNA network and recognize potential prognostic indicators for HCC. METHODS: The mutation landscape of CDKN2A in HCC was first explored using the cBioPortal database. Differential expression analysis was implemented between CDKN2Ahigh and CDKN2Alow expression HCC samples. The targeted microRNAs were predicted by lncBasev3.0, and the targeted mRNAs were predicted by miRDB, and Targetscan database. The univariate and multivariate analysis were utilized to identify independent prognostic indicators. RESULTS: CDKN2A was frequently mutated and deleted in HCC. The single-cell RNA-sequencing analysis revealed that CDKN2A participated in cell cycle pathways. The CDKN2A-related ceRNA network-growth arrest specific 5 (GAS5)/miR-25-3p/SRY-box transcription factor 11 (SOX11) was successfully established. GAS5 was recognized as an independent prognostic biomarker, whose overexpression was correlated with a poor prognosis in HCC patients. The association between GAS5 expression and methylation, immune infiltration was explored. Besides, traditional Chinese medicine effective components targeting GAS5 were obtained. CONCLUSION: This CDKN2A-related ceRNA network provides innovative insights into the molecular mechanism of HCC formation and progression. Moreover, GAS5 might be a significant prognostic biomarker and therapeutic target in HCC.

Design of a dynamic target simulator optical system with a large FOV and long exit pupil distance.

According to new generation missile test and detection requirements, it is necessary to introduce hardware-in-the-loop (HIL) simulation technology to realize the performance test of the seeker. This paper introduces the concept of secondary imaging and uses the method of focal distance allocation so that the optical system field of view (FOV) can still be greater than 6°, under the condition that the exit pupil distance is larger than 800 mm and a high-quality lighting system is designed. The design results show that when the exit pupil distance of the system is 1000 mm and the FOV is 6.4°, the modulation transfer function (MTF) of the system is 60l p/m m>0.4, and the distortion is less than 0.1%. The uniformity of the illumination system is greater than 90%, meeting the requirements of the design index.

Bibenzyl and naphthalene derivatives from Dendrobium chrysanthum and their anti-hepatic-steatosis activities.

In this study, 16 new compounds, six bibenzyls (1-6) and 10 naphthalenes (7-13), including three pairs of naphthalene enantiomers and three known compounds (14-16), were isolated from Dendrobium chrysanthum. Structurally, compounds 1-5 are previously undescribed dimeric bibenzyls, uniquely linked by unusual carbon bonds. The structures of the compounds were determined using spectroscopy and X-ray crystallography. The screening results indicated that 1, 2, and 5 showed remarkable lipid-lowering activities in FFA-induced HepG2 cells, with EC50 values ranging from 3.13 to 6.57 µM. Moreover, 1, 2, and 5 significantly decreased both the mRNA and protein levels of the target SREBP-1c, and 5 also reduced PPARα mRNA and protein levels. Therefore, 1, 2, and 5 are potential drugs against hepatic steatosis by targeting PPARα or SREBP-1c.

Primary malignant melanoma of the esophagus combined with squamous cell carcinoma: A case report.

BACKGROUND: Primary malignant melanoma of the esophagus is a rare malignant tumor of the esophagus, and its combination with squamous cell carcinoma is also rare. Here, we report the diagnosis and treatment of a case of primary esophageal malignant melanoma combined with squamous cell carcinoma. CASE SUMMARY: A middle-aged man underwent gastroscopy for dysphagia. Gastroscopy revealed multiple bulging esophageal lesions, and after pathologic and immunohistochemical analyses, the patient was finally diagnosed with "malignant melanoma with squamous cell carcinoma". This patient received comprehensive treatment. After one year of follow-up, the patient was in good condition, and the esophageal lesions seen on gastroscopy were controlled, but unfortunately, liver metastasis occurred. CONCLUSION: When multiple esophageal lesions are present, the possibility of multiple pathological sources should be considered. This patient was diagnosed with primary esophageal malignant melanoma combined with squamous cell carcinoma.

Is endoscopic mucosal ablation a valid option for treating colon polyps?

The present letter to editor is related to endoscopic mucosal ablation (EMA). EMA is safe and effective in the treatment of colonic polyps when endoscopic resection is not possible or available, but the indication of EMA should be determined for a further large number of studies. EMA should be used with caution for larger lesions.

The Effects of the SARS-CoV-2 Virus on the Cardiovascular System and Coagulation State Leading to Cardiovascular Diseases: A Narrative Review.

The novel coronavirus pandemic has led to morbidity and mortality throughout the world. Until now, it is a highly virulent contagion attacking the respiratory system in humans, especially people with chronic diseases and the elderly who are most vulnerable. A majority of afflicted are those suffering from cardiovascular and coronary diseases. In this review article, an attempt has been made to discuss and thoroughly review the mode of therapies that alleviate cardiac complications and complications due to hypercoagulation in patients infected with the SARS-CoV-2 virus. Presently a host of thrombolytic drugs are in use like Prourokinase, Retelapse, RhTNK-tPA and Urokinase. However, thrombolytic therapy, especially if given intravenously, is associated with a serious risk of intracranial haemorrhage, systemic haemorrhage, immunologic complications, hypotension and myocardial rupture. The effects of the SARS-CoV-2 virus upon the cardiovascular system and coagulation state of the body are being closely studied. In connection to the same, clinical prognosis and complications of thrombolytic therapy are being scrutinized. It is noteworthy to mention that myocardial oxygen supply/demand mismatch, direct myocardial cells injury and acute plaque rupture are the multiple mechanisms responsible for acute coronary syndrome and cardiac complications in Covid-19 infection. However, this review has limitations as data available in this context is limited, scattered and heterogenous that questions the reliability of the same. So, more multi-centric studies involving representative populations, carried out meticulously, could further assist in responding better to cardiac complications among Covid-19 patients.

Circularly polarized luminescence from helical N,O-boron-chelated dipyrromethene (BODIPY) derivatives.

We report N,O-boron-chelated dipyrromethene derivatives exhibiting circularly polarized luminescence (CPL) in the red/near-infrared region, both in solution and the aggregated state. The CPL is originated from the helical chirality through intramolecular substitution of fluorine by an alkenolic substituent. The self-assembly of the fluorophores significantly enhances the |glum| values from 10-4 to 10-2.

Genome sequencing and transcriptome analyses provide insights into the origin and domestication of water caltrop (Trapa spp., Lythraceae).

Humans have domesticated diverse species from across the plant kingdom; however, our current understanding of plant domestication is largely founded on major cereal crops. Here, we examine the evolutionary processes and genetic basis underlying the domestication of water caltrop (Trapa spp., Lythraceae), a traditional, yet presently underutilized non-cereal crop that sustained early Chinese agriculturalists. We generated a chromosome-level genome assembly of tetraploid T. natans, and then divided the allotetraploid genome into two subgenomes. Based on resequencing data from 57 accessions, representing cultivated diploid T. natans, wild T. natans (2x and 4x) and diploid T. incisa, we showed that water caltrop was likely first domesticated in the Yangtze River Valley as early as 6300 yr BP, and experienced a second improvement c. 800 years ago. We also provided strong support for an allotetraploid origin of T. natans within the past 230 000-310 000 years. By integrating selective sweep and transcriptome profiling analyses, we identified a number of genes potentially selected and/or differentially expressed during domestication, some of which likely contributed not only to larger fruit sizes but also to a more vigorous root system, facilitating nutrient uptake, environmental stress response and underwater photosynthesis. Our results shed light on the evolutionary and domestication history of water caltrop, one of the earliest domesticated crops in China. This study has implications for genomic-assisted breeding of this presently underutilized aquatic plant, and improves our general understanding of plant domestication.

Gut Microbiome-Mediated Alteration of Immunity, Inflammation, and Metabolism Involved in the Regulation of Non-alcoholic Fatty Liver Disease.

Non-alcoholic fatty liver disease (NAFLD) is one of the leading causes of end-stage liver disease, leading to a rapidly growing global public health burden. The term "gut microbiome (GM)" refers to the approximately 100 trillion microbial cells that inhabit the host's gastrointestinal tract. There is increasing evidence that GM is involved in the pathogenesis of NAFLD and may be a potential target for intervention. To explore GM-based strategies for precise diagnosis and treatment of NAFLD, great efforts have been made to develop a comprehensive and in-depth understanding of the host-microbe interaction. This review evaluates this interaction critically, mainly considering the intricate regulation of the metabolism, immunity, and inflammatory status during the evolution of the disease pathogenesis, revealing roles for the GM in NAFLD by examining advances in potential mechanisms, diagnostics, and modulation strategies. Synopsis: Considering the intricate metabolic and immune/inflammatory homeostasis regulation, we evaluate the latest understanding of the host-microbe interaction and reveal roles for the gastrointestinal microbiome in NAFLD. Strategies targeting the gastrointestinal microbiome for the diagnosis and treatment of NAFLD are proposed.

The Role and Mechanism of Autophagy in Pancreatic Cancer: An Update Review.

Pancreatic cancer, with high morbidity and mortality rates, is one of the most malignant tumors worldwide. Despite extensive research, the prognosis remains poor. Autophagy, a lysosomal-mediated, highly conserved degradation process that removes abnormal proteins and damaged organelles from the body, is upregulated in pancreatic ductal adenocarcinoma. Based on differences in the tumor microenvironment and tumor stage, the functions of autophagy in the pathophysiology and treatment of pancreatic cancer differ. In the initial phase, autophagy inhibits the transformation of precancerous lesions to cancer. However, in the progressive stage, autophagy promotes tumor growth. Autophagy is also one of the main mechanisms of drug resistance during treatment. Here, we describe the role of autophagy in pancreatic cancer progression and discuss relevant treatment strategies for this disease.

Nomogram for hepatic venous pressure gradient in patients with cirrhosis.

OBJECTIVE: The hepatic venous pressure gradient (HVPG) plays an important role in the treatment and prognosis of patients with cirrhosis. Our study aimed to develop and validate a nomogram for an HVPG >12 mmHg. METHODS: A retrospective study was performed to create a nomogram for an HVPG >12 mmHg in a training cohort that was validated in another cohort. The discriminatory ability and calibration of the nomogram were tested using the C-statistic, area under the receiver operating characteristic curve (AUROC) and calibration plots. RESULTS: The nomogram was based on portosystemic shunts identified on computed tomography images, the etiology of cirrhosis and the Child-Pugh grade. These parameters were significantly associated with an HVPG >12 mmHg (P < 0.05 for both the training and validation cohorts). In the training cohort, the model showed good discrimination (C-statistic, AUROC, and R2 of 0.71, 0.71 and 0.13, respectively) and good calibration. The total cutoff value was 112 and the sensitivity and specificity were 57.1% and 77.6%, respectively. The application of the nomogram in the validation cohort still yielded good discrimination (C-statistic 0.75 [95% confidence interval 0.61-0.89], AUROC 0.75, and R2 0.16) and good calibration. CONCLUSIONS: This nomogram is a convenient tool for predicting an HVPG >12 mmHg in patients with cirrhosis and can help clinicians quickly identify patients with decompensated cirrhosis.

"Cytokine-microfactories" recruit DCs and deliver tumor antigens via gap junctions for immunotherapy.

The majority (~80%) of patients with cancer do not derive clinical benefit from current immunotherapy, largely due to attenuation of immune responses imposed by robust immunosuppression at tumor sites. Here, a cell-based tumor antigen delivery strategy was developed to boost tumor-specific immunity. Notably, the platform constructing ferric oxide nanoparticle-trained macrophages loading tumor antigens (MFe-N) acquired an immunostimulatory program and functioned as the tumoritropic "cytokine-microfactories" to sustainably produce high levels of multiple therapeutic cytokines (GM-CSF, TNFα, and MIP-1α), which are important in activation of immune cells with antitumor potential. Indeed, MFe-N markedly enhanced recruitment of the professional antigen-presenting cells, dendritic cells (DCs), to the tumor sites of an established B16F10 mouse melanoma model. Subsequently, MFe-N effectively delivered tumor antigens to DCs by gap junction-mediated cell-to-cell transmission. And this trafficking was critical for DC maturation to augment antitumor T-cell responses. Simultaneously, the "cytokine-microfactories" elicited high production of the tumoricidal effectors, and in turn blunted the pro-angiogenic activity of tumor-associated macrophages, resulting in conversion of the tumor-supporting milieu to a tumoricidal function that favored infiltration of antitumor T-cells. The findings provided a novel "cytokine-microfactories" harnessing effective delivery of tumor antigens and production of therapeutic cytokines to robustly promote antigen presentation and reshape the tumor immune milieu for priming antitumor immunity. This can enhance existing T-cell mediated immunotherapeutic potency and extend the curative potential immunotherapy to a broader range of patients.

Neuropilin1 silencing impairs the proliferation and migration of cells in pancreatic cancer.

BACKGROUND: Neuropilin1 (NRP1) participates in cancer cell proliferation, migration, and metastasis as a multifunctional co-receptor by interacting with multiple signal pathways, but few studies have addressed the precise function of NRP1 in pancreatic cancer (PACA) cells. We aimed to study whether NRP1 gene silencing involved in the proliferation and migration of PACA cells in vitro. METHODS: A lentiviral vector expressing NRP1 shRNA was constructed and transfected into human PACA cells (CFPAC-1 and PANC-1). The expression of NRP1 protein and mRNA was detected by Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) assay, respectively. CCK-8 assay, wound healing assay, and transwell assay were conducted to examine the effect of NRP1 silencing on cells proliferation and migration capability. RESULTS: Results of qRT-PCR and Western blot showed successfully established, stably transfected shRNA-NRP1 cells in PACA cells. The proliferation capacity of PACA cells in NRP1 shRNA group was lower significantly than that in the negative control (NC) group (P < .05). The invasion and migration capability of PACA cells in NRP1 shRNA group was lower significantly than that in the NC group (P < .01). CONCLUSIONS: NRP1-shRNA lentiviral interference vectors can effectively decrease NRP1 gene expression in PACA cells, thereby inhibiting cells proliferation and migration, which provides a basis for finding a valuable therapeutic target for PACA therapy.

A FRET-based supramolecular nanoprobe with switch on red fluorescence to detect SO2 derivatives in living cells.

SO2, an important gasotransmitter, plays significant roles in human physiological activities. The reported probes for the detection of SO2 derivatives are mostly based on the quenching or blue-shift of fluorescence, leading to interference from the background signal. Herein, we develop a novel FRET-based nanoprobe that shows turn-on fluorescence at 615 nm in the presence of SO32-/HSO3-. The nanoprobe consists of N,O,B-chelated dipyrromethene (BDP) as the energy donor, and hemicyanine derivatives of HEM-CO-Ph with a responsive site to SO32-/HSO3- as the energy acceptor. Initially, the fluorescence of BDP is quenched by HEM-CO-Ph due to the efficient FRET process. In the presence of sulfites, the nucleophilic addition interrupts the conjugation of HEM-CO-Ph and results in a 200 nm blue-shift of the absorption, leading to the suppression of the FRET process and recovery of the red fluorescence of BDP. The nanoprobe shows fast response to SO32-/HSO3- with high selectivity, great biocompatibility and cellular uptake. It is the first supramolecular nanoprobe for the detection of SO32-/HSO3- by using intermolecular energy transfer, ingeniously turning the nanoprobe from "OFF" state to "ON" state. The nanoprobe is applied to monitor exogenous and endogenous SO2 derivatives in the mitochondria of living cells.

Comprehensive analysis of the differential expression profile of microRNAs in missed abortion.

To screen the key circulating microRNAs (miRNAs) involved in missed abortion (MA) and explore their role in MA process. We examined the miRNA profile from the serum of three MA patients and three early pregnancy induced abortion patients (controls) by next-generation sequencing. We analyzed the target genes of the differentially expressed (DE) miRNAs to analyze the function and pathway enrichment using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, respectively. We validated five candidate miRNAs by real time-qPCR. Integrated miRNA-mRNA-pathway network analysis was performed to show the interaction network of the candidate miRNAs and their target genes of interest with the involved pathways. It was observed that 227 miRNAs were differently expressed between the MA group and the early pregnancy control group, with 58 miRNAs downregulated and 169 miRNAs upregulated in the MA group. Real-time qPCR results revealed that expression of the five candidate miRNAs, namely hsa-miR-22-3p, hsa-miR-145-3p, hsa-miR-107, hsa-miR-361-3p, and hsa-miR-378c, was consistent with the miRNA data obtained by sequencing. Integrated miRNA-mRNA-pathway network analysis illustrated that target genes of the candidate miRNAs were mainly involved in the PI3K-Akt signaling pathway, HIF-1 signaling pathway, and VEGF signaling pathway, which would have potential significance in pregnancy and MA. We are the first to reveal the DE miRNAs involved in MA and illustrate their functional interaction network. These results might provide potential circulating biomarkers and new therapeutic targets for MA.

Arterial stiffness in adults with steady-state bronchiectasis: association with clinical indices and disease severity.

BACKGROUND: Cardiovascular disease are common co-morbidities in bronchiectasis and contribute substantially to disease burden and mortality. Brachial-ankle pulse wave velocity (baPWV), a measure of arterial stiffness, has a strong predictive value for cardiovascular event. We hypothesized that baPWV would be increased in steady-state bronchiectasis patients, and correlates with the degree of systemic inflammation and disease severity assessed with Bronchiectasis Severity Index and FACED scores. METHODS: Eighty patients with steady-state bronchiectasis and 80 age- and sex-matched controls were enrolled. BaPWV was measured as an indicator of arterial stiffness. Demographic, clinical indices, radiology, spirometry, sputum bacteriology and systemic inflammatory mediators were also assessed. RESULTS: Bronchiectasis patients had significantly increased baPWV [median 1514 cm/s vs. 1352 cm/s, P = 0.0003] compared with control subjects. BaPWV significantly correlated with Bronchiectasis Severity Index (rho = 0.65, P < 0.001) and FACED (rho = 0.49, P < 0.001) scores. In multivariate regression analysis, age, Pseudomonas aeruginosa colonization, systolic blood pressure, body-mass index and exacerbation frequency in the last 12 months, but not systemic inflammatory markers, were independent factors influencing on baPWV in bronchiectasis patient after adjustment for other clinical variables. Reproducibility of baPWV measurement was good. CONCLUSION: Bronchiectasis patients have increased arterial stiffness compared with control subjects, which correlates with disease severity, but not systemic inflammatory markers. Age, Pseudomonas aeruginosa colonization, systolic blood pressure, body-mass index and exacerbation frequency in last 12 months might independently predict the severity of arterial stiffness in bronchiectasis. Therefore, arterial stiffness might have contributed to the increased risks of developing cardiovascular diseases in bronchiectasis.

Subclinical atherosclerosis in adults with steady-state bronchiectasis: A case-control study.

BACKGROUND AND OBJECTIVE: Bronchiectasis has been associated with increased risks of cardiovascular disease, in which early-stage endothelial dysfunction might have played pivotal roles. We aimed to investigate endothelial function in bronchiectasis patients, by measuring flow-mediated dilatation (FMD) and carotid intima-media thickness (CIMT) as compared with control subjects, and to elucidate the impact of different risk factors on subclinical atherosclerosis. METHODS: The study included 80 bronchiectasis patients and 80 age- and sex-matched healthy subjects. Vascular endothelial function was evaluated with FMD in the brachial artery in response to reactive hyperemia, and CIMT was measured with high-resolution ultrasonography. Disease severity was evaluated with Bronchiectasis Severity Index and FACED scores. Demographic, disease duration, radiology, spirometry, sputum bacteriology and systemic inflammatory indices were also assessed. RESULTS: FMD was significantly lower in bronchiectasis patients than in control subjects (8.92 ± 2.70% vs. 11.17 ± 3.44%, P < 0.001). FMD significantly correlated with Bronchiectasis Severity Index (rho = -0.60, P < 0.001) and FACED score (rho = -0.39, P < 0.001). In multivariate regression analysis, age, body-mass index, Pseudomonas aeruginosa colonization and high-resolution computed tomography scores were independent factors influencing on the FMD in bronchiectasis patients, even after adjustment for other clinical variables. No significant difference in CIMT was detected between bronchiectasis patients and healthy subjects (P > 0.05). CONCLUSIONS: Compared with healthy subjects, bronchiectasis patients have greater risks of endothelial dysfunction which is independent of previously well-studied risk factors, calling for the vigilance to screen early for vascular changes to minimize the future risks of cardiovascular events.

SUMO-specific protease 2-mediated deSUMOylation is required for NDRG2 stabilization in gastric cancer cells.

N-myc downstream regulated gene 2 (NDRG2) is frequently down-regulated in various cancers and functions as a candidate tumor suppressor gene. NDRG2 has been shown to be SUMOylated on the lysine 333 residue, which promoted its ubiquitination and sequentially degradation by the SUMO-targeted ubiquitin E3 ligase RNF4. However, how to regulated NDRG2 deSUMOylation process remains largely unknown. Here, we report that Sentrin/SUMO specific protease (SENP2) was down-regulated in clinic gastric cancer samples and possessed a tumor-suppressive role in gastric cancer. At the molecular level, we found that SENP2 interacts with NDRG2 and mediates the de-SUMOylation process of NDRG2. Overexpression of SENP2 stabilized NDRG2, whereas silencing SENP2 caused rapid NDRG2 SUMOylation and degradation, indicating SENP2 antagonizes NDRG2 ubiquitination and degradation, thereby promoting the stability and function of this protein. Thus, our study reveals that SENP2 acts as a tumor suppressor which is deregulated in gastric cancer and the specific de-SUMOylation activity of SENP2 for NDRG2 is critical for it stabilization as well as gastric cancer cells proliferation.

Self-assembled structures of N-alkylated bisbenzimidazolyl naphthalene in aqueous media for highly sensitive detection of picric acid.

A 2,6-dibenzimidazole-appended naphthalene derivative flanking with two N-alkyl chains (sensor 4) was designed and applied for highly sensitive detection of picric acid (PA) in aqueous media. Driven by the hydrophobicity of alkyl chain and π-π stacking effect of aryl, sensor 4 can undergo self-assembly to form an orderly rod-like structure in H2O/THF (v/v, 90/10) solution, as shown by the dynamic light scattering (DLS) and scanning electron microscopy (SEM) studies. Sensor 4 shows high selectivity and sensitivity toward PA over other nitroaromatic explosives. DFT calculations and 1H NMR, the time-correlated single photon counting (TCSPC) experiments confirm that the quenching mechanism is due to both electron and energy transfer from the electron-rich sensor 4 to the electron-deficient PA. Sensor 4 can detect as low as 0.57 ppb PA in aqueous media and 11.46 ag cm-2 PA by contact mode. Importantly, sensor 4 exhibits low interference against common solvents, metal ions and anions. Thus, it is practically applicable for sensing PA in real environmental samples and vapor phase.