Search

The purpose of this study was to investigate the drug-resistant phenotypes and genes of Escherichia coli in animal, environmental, and human samples before and after antibiotic use at a large-scale broiler farm to understand the respective effects on E. coli resistance during the broiler feeding cycle. The antibiotic use per broiler house was 143.04 to 183.50 mg/kg, and included tilmicosin, florfenicol, apramycin, and neomycin. All strains isolated on the first day the broilers arrived (T1; day 1) were antibiotic-resistant bacteria. E. coli strains isolated from animal samples were resistant to ampicillin, tetracycline, and sulfamethoxazole (100%), and those isolated from environmental samples were resistant to 5 different drugs (74.07%, 20 of 27). E. coli strains isolated on the last day before the broilers left (T2; day 47) had a higher resistance rate to florfenicol (100%, 36 of 36) than at T1 (P

The microbial contamination of pork during the slaughter process, especially that of the hygiene indicator bacteria, Escherichia coli, is closely related to the safety and quality of the meat. Some diarrheagenic E. coli can cause serious foodborne diseases, and pose a significant threat to human life and health. In order to ascertain the current status of E. coli and diarrheagenic E. coli contamination during the pig slaughter process in China, we conducted thorough monitoring of large-sized slaughterhouses, as well as small- or medium-sized slaughterhouses, in different provinces of China from 2019 to 2020. The overall positive rate of E. coli on the pork surface after slaughter was very high (97.07%). Both the amount of E. coli contamination and the positive ratio of diarrheagenic E. coli in large-sized slaughterhouses (7.50–13.33 CFU/cm2, 3.44%) were lower than those in small- or medium-sized slaughterhouses (74.99–133.35 CFU/cm2, 5.71%). Combined with the current status of sanitary control in slaughterhouses, we determined that pre-cooling treatment significantly reduced E. coli and diarrheagenic E. coli in pork after slaughter, while microbiological testing reduced E. coli. Based on our monitoring data, China urgently needs to establish relevant standards to better control microbial contamination during pig slaughtering progress. This study provided a theoretical basis for the hygiene quality management of the pig slaughter industry in China.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death globally. Currently there is a lack of tumor-selective and efficacious therapies for hepatocellular carcinoma. β-Lapachone (ARQ761 in clinical form) selectively kill NADPH: quinone oxidoreductase 1 (NQO1)-overexpressing cancer cells. However, the effect of β-Lapachone on HCC is virtually unknown. In this study, we found that relatively high NQO1 and low catalase levels were observed in both clinical specimens collected from HCC patients and HCC tumors from the TCGA database. β-Lapachone treatment induced NQO1-selective killing of HCC cells and caused ROS formation and PARP1 hyperactivation, resulting in a significant decrease in NAD+ and ATP levels and a dramatic increase in double-strand break (DSB) lesions over time in vitro. Administration of β-Lapachone significantly inhibited tumor growth and prolonged survival in a mouse xenograft model in vivo. Our data suggest that NQO1 is an ideal potential biomarker, and relatively high NQO1:CAT ratios in HCC tumors but low ratios in normal tissues offer an optimal therapeutic window to use β-Lapachone. This study provides novel preclinical evidence for β-Lapachone as a new promising chemotherapeutic agent for use in NQO1-positive HCC patients.

Purpose: Development of tumor-specific therapies for the treatment of recalcitrant non–small cell lung cancers (NSCLC) is urgently needed. Here, we investigated the ability of β-lapachone (β-lap, ARQ761 in clinical form) to selectively potentiate the effects of ionizing radiation (IR, 1–3 Gy) in NSCLCs that overexpress NAD(P)H:Quinone Oxidoreductase 1 (NQO1). Experimental Design: The mechanism of lethality of low-dose IR in combination with sublethal doses of β-lap was evaluated in NSCLC lines in vitro and validated in subcutaneous and orthotopic xenograft models in vivo. Pharmacokinetics and pharmacodynamics (PK/PD) studies comparing single versus cotreatments were performed to validate therapeutic efficacy and mechanism of action. Results: β-Lap administration after IR treatment hyperactivated PARP, greatly lowered NAD+/ATP levels, and increased double-strand break (DSB) lesions over time in vitro. Radiosensitization of orthotopic, as well as subcutaneous, NSCLCs occurred with high apparent cures (>70%), even though 1/8 β-lap doses reach subcutaneous versus orthotopic tumors. No methemoglobinemia or long-term toxicities were noted in any normal tissues, including mouse liver that expresses the highest level of NQO1 (∼12 units) of any normal tissue. PK/PD responses confirm that IR + β-lap treatments hyperactivate PARP activity, greatly lower NAD+/ATP levels, and dramatically inhibit DSB repair in exposed NQO1+ cancer tissue, whereas low NQO1 levels and high levels of catalase in associated normal tissue were protective. Conclusions: Our data suggest that combination of sublethal doses of β-lap and IR is a viable approach to selectively treat NQO1-overexpressing NSCLC and warrant a clinical trial using low-dose IR + β-lap against patients with NQO1+ NSCLCs.

Significance: Head and neck squamous cell cancer (HNSCC) is a complex disease characterized by high genetic and metabolic heterogeneity. Radiation therapy (RT) alone or combined with systemic chemotherapy is widely used for treatment of HNSCC as definitive treatment or as adjuvant treatment after surgery. Antibodies against epidermal growth factor receptor are used in definitive or palliative treatment. Recent Advances: Emerging targeted therapies against other proteins of interest as well as programmed cell death protein 1 and programmed death-ligand 1 immunotherapies are being explored in clinical trials. Critical Issues: The disease heterogeneity, invasiveness, and resistance to standard of care RT or chemoradiation therapy continue to constitute significant roadblocks for treatment and patients' quality of life (QOL) despite improvements in treatment modality and the emergence of new therapies over the past two decades. Future Directions: As reviewed here, alterations in redox metabolism occur at all stages of HNSCC management, providing opportunities for improved prevention, early detection, response to therapies, and QOL. Bioinformatics and computational systems biology approaches are key to integrate redox effects with multiomics data from cells and clinical specimens and to identify redox modifiers or modifiable target proteins to achieve improved clinical outcomes. Antioxid. Redox Signal.

OBJECTIVE This study aimed to evaluate the efficacy and safety of mulberry twig alkaloids (Sangzhi alkaloids [SZ-A]) in the treatment of type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS This was a multicenter, randomized, double-blind, double-dummy, and parallel controlled noninferiority clinical trial that was conducted for 24 weeks. A total of 600 patients were randomly allocated to the SZ-A group (n = 360) or acarbose group (n = 240). The primary efficacy end point was the change of glycosylated hemoglobin (HbA1c) compared with baseline. In addition, adverse events (AEs), severe AEs (SAEs), treatment-related AEs (TAEs), and gastrointestinal disorders (GDs) were monitored. RESULTS After treatment for 24 weeks, the change in HbA1c was –0.93% (95% CI –1.03 to –0.83) (–10.2 mmol/mol [–11.3 to –9.1]) and –0.87% (–0.99 to –0.76) (–9.5 mmol/mol [–10.8 to –8.3]) in the SZ-A and acarbose groups, respectively, and the least squares mean difference was –0.05% (95% CI –0.18 to 0.07) (–0.5 mmol/mol [–2.0 to 0.8]) between the two groups, with no significant difference on the basis of covariance analysis (P > 0.05). The incidence of TAEs and GDs was significantly lower in the SZ-A group than the acarbose group (P < 0.01), but no differences for AEs or SAEs between the two groups were observed (P > 0.05). CONCLUSIONS SZ-A exhibited equivalent hypoglycemic effects to acarbose in patients with T2D. Nevertheless, the incidence of TAEs and GDs was lower following SZ-A treatment than acarbose treatment, suggesting good safety.

Ionizing radiation (IR) creates lethal DNA damage that can effectively kill tumor cells. However, the high dose required for a therapeutic outcome also damages healthy tissue. Thus, a therapeutic strategy with predictive biomarkers to enhance the beneficial effects of IR allowing a dose reduction without losing efficacy is highly desirable. NAD(P)H:quinone oxidoreductase 1 (NQO1) is overexpressed in the majority of recalcitrant solid tumors in comparison with normal tissue. Studies have shown that NQO1 can bioactivate certain quinone molecules (e.g., ortho-naphthoquinone and β-lapachone) to induce a futile redox cycle leading to the formation of oxidative DNA damage, hyperactivation of poly(ADP-ribose) polymerase 1 (PARP1), and catastrophic depletion of NAD+ and ATP, which culminates in cellular lethality via NAD+-Keresis. However, NQO1-bioactivatable drugs induce methemoglobinemia and hemolytic anemia at high doses. To circumvent this, NQO1-bioactivatable agents have been shown to synergize with PARP1 inhibitors, pyrimidine radiosensitizers, and IR. This therapeutic strategy allows for a reduction in the dose of the combined agents to decrease unwanted side effects by increasing tumor selectivity. In this review, we discuss the mechanisms of radiosensitization between NQO1-bioactivatable drugs and IR with a focus on the involvement of base excision repair (BER). This combination therapeutic strategy presents a unique tumor-selective and minimally toxic approach for targeting solid tumors that overexpress NQO1.

Chickens contaminated with Campylobacter are a major risk factor for human Campylobacter disease. As a result of the slaughter process, infections should be strictly controlled due to complete exposure of the chickens and the cross-contamination of pathogens. Using @RISK software, quantitative evaluation models of Campylobacter contamination during slaughtering in a large broiler slaughterhouse were constructed. Broiler scalding was set as the starting point of evaluation and four major processes including defeathering, eviscerating, pre-cool rinsing, and splitting-transmission were included. Through the simulation of the constructed model, 90% probability of Campylobacter in 100 g chickens after slaughtering were distributed between 0.3 and 50.2 MPN, which was consistent with simulated actual monitoring data 0–16.6 MPN, indicating that the model shows high credibility. In addition, growth curves of Campylobacter during whole slaughtering showed that contamination significantly increased after defeathering, and increased again after pre-cool rinsing. Using correlation coefficients to analyze the sensitivity of each parameter in the model, it was determined that the concentration of Campylobacter in the pre-cool pond water (correlation coefficient: 0.95) was the most critical risk point of sanitary control in this slaughterhouse. In conclusion, this study is the first to incorporate environmental factors during broiler slaughtering into the risk evaluation of Campylobacter contamination, which provides guidance for the sanitary control and risk management of Campylobacter contamination during broiler slaughtering.

Developing cancer therapeutics that radiosensitize in a tumor-selective manner remains an ideal. We developed a novel means of radiosensitization, exploiting NAD(P)H:Quinone Oxidoreductase 1 (NQO1) overexpression, and lowered catalase expression in solid human tumors using NQO1-bioactivatable drugs. Non-small cell lung (NSCLC), pancreatic (PDAC), prostate, and breast cancers overexpress NQO1. Ionizing radiation (IR) creates a spectrum of DNA lesions, including lethal DNA double-strand breaks (DSBs), and mutagenic but rarely lethal altered DNA bases and DNA single-strand breaks (SSBs). NQO1-bioactivatable drugs (e.g., β-lapachone and deoxynyboquiones) also promote abasic DNA lesions and SSBs. These hyperactivate poly (ADP-ribose) polymerase 1 (PARP1) and dramatically increase calcium release from the endoplasm reticulum (ER). Exposure of human cancer cells overexpressing NQO1 to NQO1-bioactivatable drugs immediately following IR, therefore, hyperactivates PARP1 synergistically, which in turn depletes NAD+ and ATP, inhibiting DSB repair. Ultimately, this leads to cell death. Combining IR with NQO1-bioactivatable drugs allows for a reduction in drug dose. Similarly, a lower IR dose can be used in combination with the drug, reducing the effects of IR on normal tissue. The combination treatment is effective in preclinical animal models with NSCLC, prostate, and head and neck xenografts, indicating that clinical trials are warranted.

Most patients are resistant to PD-1/PD-L1 blockade therapy but mechanisms are not well defined. Defective innate sensing limits reactivation of T cells after the blockade. Patients with well-established solid tumors often generate complicated immunosuppressive networks and are generally refractory to immunotherapy. NAD(P)H:quinone oxidoreductase 1 (NQO1) is a two-electron oxidoreductase elevated (more than 100-fold) in most solid cancers and has emerged as a promising target for direct tumor-killing. Here, we demonstrate that novel NQO1 targeting drug-Isobutyldeoxynyboquinone (IB-DNQ) causes tumor-selective innate sensing leading to T cell dependent tumor suppression. IB-DNQ treatment increases PD-L1 expression in the tumor microenvironment. Upregulated PD-L1 within TME contributes to tumor relapse and provides therapeutic window for combination therapy of IB-DNQ with immune checkpoint blockade. We demonstrate that IB-DNQ or PD-1 blockade treatment alone leads to tumor rejection in mice bearing small but not large established tumors. However, combination therapy of IB-DNQ with anti-PD-L1 eradicates well-established and checkpoint blockade refractory tumors. Citation Format: Lingxiang Jiang, Paul J. Hergenrother, Xiumei Huang. Tumor selective immunotherapy to overcome checkpoint blockade resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1657.

Novel, tumor-selective therapies are needed to increase the survival rate of pancreatic cancer patients. K-Ras-mutant-driven NAD(P)H:quinone oxidoreductase 1 (NQO1) is over-expressed in pancreatic tumor versus associated normal tissue, while catalase expression is lowered compared to levels in associated normal pancreas tissue. ARQ761 undergoes a robust, futile redox cycle in NQO1+ cancer cells, producing massive hydrogen peroxide (H2 O2 ) levels; normal tissues are spared by low NQO1 and high catalase expression. DNA damage created by ARQ761 in pancreatic cancer cells "hyperactivates" PARP1, causing metabolic catastrophe and NAD ± keresis cell death. NQO1: catalase levels (high in tumor, low in normal tissue) are an attractive therapeutic window to treat pancreatic cancer. Based on a growing body of literature, we are leading a clinical trial to evaluate the combination of ARQ761 and chemotherapy in patients with pancreatic cancer.

Lack of proper innate sensing inside tumor microenvironment (TME) limits T cell-targeted immunotherapy. NAD(P)H:quinone oxidoreductase 1 (NQO1) is highly enriched in multiple tumor types and has emerged as a promising target for direct tumor-killing. Here, we demonstrate that NQO1-targeting prodrug β-lapachone triggers tumor-selective innate sensing leading to T cell-dependent tumor control. β-Lapachone is catalyzed and bioactivated by NQO1 to generate ROS in NQO1high tumor cells triggering oxidative stress and release of the damage signals for innate sensing. β-Lapachone-induced high mobility group box 1 (HMGB1) release activates the host TLR4/MyD88/type I interferon pathway and Batf3 dendritic cell-dependent cross-priming to bridge innate and adaptive immune responses against the tumor. Furthermore, targeting NQO1 is very potent to trigger innate sensing for T cell re-activation to overcome checkpoint blockade resistance in well-established tumors. Our study reveals that targeting NQO1 potently triggers innate sensing within TME that synergizes with immunotherapy to overcome adaptive resistance., Improper innate sensing within the tumor microenvironment limits immunotherapy success. Here, the authors show that targeting NQO1 triggers immunogenic innate sensing to reactivate T cells and overcome immune checkpoint blockade resistance.

Alzheimer’s disease (AD) is the most common form of dementia in the elderly. It is generally believed that β-amyloidogenesis, tau-hyperphosphorylation and synaptic loss underlie cognitive decline in AD. Rps23rg1, a functional retroposed mouse gene, has been shown to reduce Alzheimer’s β-amyloid (Aβ) production and tau phosphorylation. In this study, we have identified its human homolog and demonstrated that RPS23RG1 regulates synaptic plasticity, thus counteracting Aβ oligomer (oAβ)-induced cognitive deficits in mice. The level of RPS23RG1 mRNA is significantly lower in the brains of AD compared to non-AD patients, suggesting its potential role in the pathogenesis of the disease. Similar to its mouse counterpart, human RPS23RG1 interacts with adenylate cyclase, activating PKA/CREB and inhibiting GSK-3. Furthermore, we show that human RPS23RG1 promotes synaptic plasticity and offsets oAβ-induced synaptic loss in a PKA-dependent manner in cultured primary neurons. Overexpression of Rps23rg1 in transgenic mice consistently prevented oAβ-induced PKA inactivation, synaptic deficits, suppression of long-term potentiation and cognitive impairment as compared to wild type littermates. Our study demonstrates that RPS23RG1 may reduce the occurrence of key elements of AD pathology and enhance synaptic functions to counteract oAβ-induced synaptic and cognitive deficits in AD.

Inhibitors of cancer-specific pathways can selectively kill off tumor cells. However, heterogeneity of neoplastic tissue often allows other cancer cells to repopulate the tissue area, leading to regeneration of resistant disease. β-Lapachone is a novel bioactivatable drug that relies specifically on tumor-directed upregulated levels of NAD(P)H:quinone oxidoreductase 1 (NQO1) to kill most solid cancers, such as 90 % of pancreatic and non-small cell lung, 60 % of breast, colon, and prostate, as well as 50 % of head and neck cancers. Once β-lapachone is bioactivated by the NQO1 enzyme, massive levels of hydrogen peroxide are produced that, in turn, damage the DNA of cancer cells, while associated normal tissues, which lack NQO1, are protected by high levels of catalase. If tumors are irradiated prior to applying β-lapachone, the drug (clinical form, ARQ761) can work in combination with the vast spectrum of DNA lesions created by ionizing radiation, particularly DNA base lesions, single and double strand breaks (SSBs and DSBs), in addition to the massive hydrogen peroxide-based lesions created by β-lapachone, to cause tumor-dependent poly(ADP-ribose) polymerase 1 (PARP1) hyperactivation. Once tumor-selective PARP hyperactivation is induced in cancer cells, they die due to low concomitant catalase levels. In contrast, associated normal tissue, as well as other normal tissue, lack elevated levels of NQO1 and have high catalase levels. Cancer cell death ultimately occurs by NAD+-depletion, where resistance to NQO1 bioactivatable drugs has not been noted to date. Current studies are focused on pancreatic and non-small cell lung cancers, as NQO1 is elevated in nearly all of these cancers.

Apoptosis is an essential cellular process in multiple diseases and a major pathway for neuronal death in neurodegeneration. The detailed signaling events/pathways leading to apoptosis, especially in neurons, require further elucidation. Here we identify a β-amyloid precursor protein (APP)-interacting protein, designated as appoptosin, whose levels are upregulated in brain samples from Alzheimer's disease and infarct patients, and in rodent stroke models, as well as in neurons treated with β-amyloid (Aβ) and glutamate. We further demonstrate that appoptosin induces reactive oxygen species release and intrinsic caspase-dependent apoptosis. The physiological function of appoptosin is to transport/exchange glycine/5-amino-levulinic acid across the mitochondrial membrane for heme synthesis. Downregulation of appoptosin prevents cell death and caspase activation caused by glutamate or Aβ insults. APP modulates appoptosin-mediated apoptosis through interaction with appoptosin. Our study identifies appoptosin as a crucial player in apoptosis and a novel pro-apoptotic protein involved in neuronal cell death, providing a possible new therapeutic target for neurodegenerative disorders.

This study investigated the psychological characteristics and clinical features of 55 patients with geriatric depression, and evaluated the efficacy and safety of escitalopram in the treatment of geriatric depression, in a randomized controlled trial. Fifty-five patients with geriatric depression were randomly assigned to receive 8 weeks of escitalopram 10 mg, daily, orally ( n = 29) or placebo ( n = 26). At baseline, these patients had significantly higher neuroticism and psychoticism scores on the Eysenck Personality Questionnaire - Adult scale than Chinese population norms. General Severity Index scores and the mean values of the nine subscales of the Symptom Checklist-90- Revised scale were also significantly higher in these patients than in Chinese population norms. The response rate to escitalopram after 8 weeks' treatment was 74.1% (20/27 patients). Adverse reactions included nausea, dry mouth and dizziness. In conclusion, depressed geriatric patients were found to have abnormal personality traits, and escitalopram was efficacious and had a good safety profile in the treatment of geriatric depression.

Alzheimer's disease (AD) is characterized by the formation of extracellular senile plaques in the brain, whose major component is a small peptide called beta-amyloid (Abeta). Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) has been found beneficial for AD and several reports suggest that NSAIDs reduce the generation of Abeta, especially the more amyloidogenic form Abeta42. However, the exact mechanism underlying NSAIDs' effect on AD risk remains largely inconclusive and all clinical trials using NSAIDs for AD treatment show negative results so far. Recent studies have shown that some NSAIDs can bind to certain nuclear receptors, suggesting that nuclear receptors may be involved in NSAID's effect on AD risk. Here we find that (R)-flurbiprofen, the R-enantiomer of the racemate NSAID flurbiprofen, can significantly reduce Abeta secretion, but at the same time, increases the level of intracellular Abeta. In addition, we find that a nuclear receptor, retinoid X receptor alpha (RXRalpha), can regulate Abeta generation and that down-regulation of RXRalpha significantly increases Abeta secretion. We also show that (R)-flurbiprofen can interfere with the interaction between RXRalpha and 9-cis-retinoid acid, and that 9-cis-retinoid acid decreases (R)-flurbiprofen's reduction of Abeta secretion. Moreover, the modulation effect of (R)-flurbiprofen on Abeta is abolished upon RXRalpha down-regulation. Together, these results suggest that RXRalpha can regulate Abeta generation and is also required for (R)-flurbiprofen-mediated Abeta generation.

Current cancer chemotherapy lacks specificity and is limited by undesirable toxic side-effects, as well as a high rate of recurrence. Nanotechnology has the potential to offer paradigm-shifting solutions to improve the outcome of cancer diagnosis and therapy. β-Lapachone (β-lap) is a novel anticancer agent whose mechanism of action is highly dependent onquinone oxidoreductase 1 (NQO1), a phase II detoxifying enzyme overexpressed in solid tumors from a variety of cancer types. However, the poor water solubility of β-lap limits its clinical potential. A series of drug formulations were developed for systemic administration in preclinical evaluations. Encapsulation of β-lap into polymeric micelles showed less side-effects and higher maximum tolerated dose (MTD), prolonged blood circulation time and preferential accumulation in tumors with greatly improved safety and antitumor efficacy. The prodrug strategy of β-lap further decreases the crystallization of β-lap by introducing esterase degradable side chains to the rigid fused ring structure. β-Lap prodrugs considerably increased the stability, drug-loading content and delivery efficiency of nanoparticles. The optimized formulation of β-lap-dC3 prodrug micelles showed excellent antitumor efficacy in treating orthotopic non-small cell lung tumors that overexpress NQO1, with target validation using pharmacodynamic endpoints.

Lung cancer is one of the most lethal forms of cancer and current chemotherapeutic strategies lack broad specificity and efficacy. Recently, β-lapachone (β-lap) was shown to be highly efficacious in killing non-small cell lung cancer (NSCLC) cells regardless of their p53, cell cycle and caspase status. Pre-clinical and clinical use of β-lap (clinical form, ARQ501 or 761) is hampered by poor pharmacokinetics and toxicity due to hemolytic anemia. Here, we report the development and preclinical evaluation of β-lap prodrug nanotherapeutics consisting of diester derivatives of β-lap encapsulated in biocompatible and biodegradable poly(ethylene glycol)-b-poly(d,l-lactic acid) (PEG-b-PLA) micelles. Compared to the parent drug, diester derivatives of β-lap showed higher drug loading densities inside PEG-b-PLA micelles. After esterase treatment, micelle-delivered β-lap-dC3 and -dC6 prodrugs were converted to β-lap. Cytotoxicity assays using A549 and H596 lung cancer cells showed that both micelle formulations maintained NAD(P)H:quinone oxidoreductase 1 (NQO1)-dependent cytotoxicity. However, antitumor efficacy study of β-lap-dC3 micelles against orthotopic A549 NSCLC xenograft-bearing mice showed significantly greater long-term survival over β-lap-dC6 micelles or β-lap-HPβCD complexes. Improved therapeutic efficacy of β-lap-dC3 micelles correlated with higher area under the concentration-time curves of β-lap in tumors, and enhanced pharmacodynamic endpoints (e.g., PARP1 hyperactivation, γH2AX, and ATP depletion). β-Lap-dC3 prodrug micelles provide a promising strategy for NQO1-targeted therapy of lung cancer with improved safety and antitumor efficacy.

This work is to study the anti-inflammatory effect and its mechanisms of sophoridine in vitro and in vivo. For this aim, the influences of sophoridine on several inflammatory mediators were investigated. Excessive inflammatory response in vitro model was developed by using lipopolysaccharide (LPS) to stimulate the mouse peritoneal macrophages and HL-60 cells to produce IL-6 and IL-8. Carrageenin-induced mouse paw edema model was used as inflammatory response in vivo model. MTT method, ultraviolet spectrophotometric method, and radioimmunoassay were used to measure the changes of TNFα, IL-6, PGE2, and IL-8 in in vitro cell culture supernatant or in the local inflammatory exudates. The results showed that sophoridine inhibited the production of IL-8 in in vitro cell culture supernatant and inhibited the production of TNFα, PGE2, and IL-8 in the local inflammatory exudates but had no significant effects on the production of IL-6 in vitro and in vivo. It is demonstrated that sophoridine’s anti-inflammatory effect was due to its ability to inhibit the production of cytokine and inflammatory mediators.

Agents, such as β-lapachone, that target the redox enzyme, NAD(P)H:quinone oxidoreductase 1 (NQO1), to induce programmed necrosis in solid tumors have shown great promise, but more potent tumor-selective compounds are needed. Here, we report that deoxynyboquinone kills a wide spectrum of cancer cells in an NQO1-dependent manner with greater potency than β-lapachone. Deoxynyboquinone lethality relies on NQO1-dependent futile redox cycling that consumes oxygen and generates extensive reactive oxygen species (ROS). Elevated ROS levels cause extensive DNA lesions, PARP1 hyperactivation, and severe NAD+/ATP depletion that stimulate Ca2+–dependent programmed necrosis, unique to this new class of NQO1 “bioactivated” drugs. Short-term exposure of NQO1+ cells to deoxynyboquinone was sufficient to trigger cell death, although genetically matched NQO1− cells were unaffected. Moreover, siRNA-mediated NQO1 or PARP1 knockdown spared NQO1+ cells from short-term lethality. Pretreatment of cells with BAPTA-AM (a cytosolic Ca2+ chelator) or catalase (enzymatic H2O2 scavenger) was sufficient to rescue deoxynyboquinone-induced lethality, as noted with β-lapachone. Investigations in vivo showed equivalent antitumor efficacy of deoxynyboquinone to β-lapachone, but at a 6-fold greater potency. PARP1 hyperactivation and dramatic ATP loss were noted in the tumor, but not in the associated normal lung tissue. Our findings offer preclinical proof-of-concept for deoxynyboquinone as a potent chemotherapeutic agent for treatment of a wide spectrum of therapeutically challenging solid tumors, such as pancreatic and lung cancers. Cancer Res; 72(12); 3038–47. ©2012 AACR.

The major problem plaguing DNA repair and metabolic inhibitors is their lack of tumor-selectivity, resulting in unwanted toxicities. In contrast, NAD(P)H:quinone oxidoreductase 1 (NQO1) bioactivatable drugs (e.g., ß-lapachone (ß-lap) and deoxynyboquinine (DNQ) and their derivatives) offer exquisite tumor-selectivity, with one form of the drug, ARQ761, currently in Phase I clinical trials against solid cancers, most of which have elevated levels of NQO1; pancreatic and nonsmall cell lung cancers (NSCLC) have the highest levels of this two-electron oxidoreductase. NQO1 levels are elevated during early steps of carcinogenesis in most solid cancers in response to activated K-Ras, c-Myc or other oncogenic drivers, as well as re-expression of human telomerase (hTERT). NQO1 catalyzes an unique futile redox cycle using either of these two unique classes of NQO1 bioactivatable drugs, resulting in super-lethal doses of hydrogen peroxide; in fact one mole of ß-lap used by NQO1 produces >60 moles H2O2 in 2 mins. The elevated levels of H2O2 generates tremendous DNA lesions (e.g., 8-oxoguanine formation) that ultimately results in massive levels of DNA single strand breaks. The H2O2 generated also results in release of ERCa2+ and culminates in the hyperactivation of Poly(ADP-ribose) polymerase (PARP1). GAPDH is then inhibited initially by direct suppression by H2O2 and then by posttranslational modification, resulting in accumulation of glyceraldehyde-3phosphate (GA3P). This unique, NQO1-dependent tumor-selective hyperactivation of PARP1 results in simultaneous losses of NAD+ (generated by the NQO1 futile redox cycle) and ATP, with suppressed recovery by inhibition of glycolysis (by inhibition of GAPDH) and the Krebs cycle through suppression of pyruvate production. Understanding the mechanism of action of these two classes of unique drugs has allowed tumor-selective combination therapies with DNA damaging agents, DNA repair inhibitors, and more recently metabolic inhibitors, such as agents that block NaMPt and GLS1. Addition of these inhibitors, in turn, results in a dramatic lowering of the required doses of NQO1 bioactivatable drugs-a true synergy is established with nontoxic levels of drugs combined to achieve one log or greater loss of colony forming ability. This work is supported by grants from Texas CPRIT, AACR/PanCan Action Network and NIH R01 CA102792-11 to DAB. Citation Format: Xiumei Huang, Zachary Moore, Xiuquan Luo, Gaurab Chakrabarti, Mariya Ilcheva, Rolf Brekken, Sandeep Burma, Jinming Gao, Ralph Deberardinis, William Bornmann, Paul Hergenrother, David A. Boothman. DNA repair and metabolism inhibitors are tumor-selective when combined with NQO1 bioactivatable drugs for therapy against pancreatic and nonsmall cell lung cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 787. doi:10.1158/1538-7445.AM2014-787

Pancreatic cancer will be the second leading cause of cancer-related deaths in the US by 2020, where 5-year survival is To improve its efficacy, we examined the synergistic effects of adding the AP site-modifying drug and base excision repair (BER) inhibitor, methoxyamine (MeOX), with beta-lap against NQO1 over-expressing pancreatic cancer cells. MeOX + beta-lap synergy resulted in: a, enhanced lethality of sublethal doses of beta-lap, reducing the shoulder (Dq), increasing the lethality rate (Do), and inducing apoptosis (TUNEL+) in NQO1+, but not in NQO1-, MIA PaCa-2 cells; b, increased DNA lesion formation; c, dramatic losses in ATP levels, with little recovery; and d, dramatic suppression of glycolysis. These data strongly suggests that MeOX enhances PARP1 hyperactivation and synergistic cell killing of beta-lap. Similar results were noted in shRNA-XRCC1 knockdown cells. Mechanistically, our data suggests that PARP1 detects MeOX-AP modified sites or SSBs, allowing PARP1 hyperactivation and synergistic cell death. Since MeOX is a nontoxic agent, and both agents are currently in clinical trials (i.e., beta-lap as Arq761, Arqule, Boston, MA), combination therapies for the treatment of pancreatic, as well as other NQO1 over-expressing solid cancers could be rapidly developed. An AACR Innovator Award from the George and June Block Foundation to DAB supported this work. Citation Format: Xiuquan Luo, Longshan Li, Xiumei Huang, Lifen Cao, Zachary Moore, Ralph Deberardinis, Rolf Brekken, Stanton Gerson, Lili Liu, David A. Boothman. Inhibiting base excision repair synergistically enhances beta-lapachone-mediated ‘kiss of death’ for tumor-selective therapy of pancreatic cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3344. doi:10.1158/1538-7445.AM2013-3344

Alzheimer's disease (AD) is characterized by the deposition of β-amyloid (Aβ) peptides in the brain, inducing neuronal cell death and microglial activation. Endoplasmic reticulum (ER) stress has been proposed to be a mediator of Aβ neurotoxicity. In this study, we test whether salubrinal, an ER stress inhibitor, can protect against Aβ-mediated neurotoxicity. We show in rat primary cortical neurons and mouse microglial BV-2 cells that short-term treatment with salubrinal attenuates Aβ-induced neuronal death and microglial activation. Remarkably, our results show that salubrinal's neuroprotective effects are not due to inhibition of ER stress. Rather, we demonstrate that salubrinal exerts its effects through the inhibition of IκB kinase (IKK) activation, IκB degradation, and the subsequent nuclear factor-kappa B (NF-κB) activation. These results elucidate inhibition of the NF-κB pathway as a new mechanism responsible for the protective effects of salubrinal against Aβ neurotoxicity. This study also suggests that modulation of Aβ-induced NF-κB activation could be a potential therapeutic strategy for Alzheimer's disease.

Summary Senile plaques consisting of β-amyloid (Aβ) and neurofibrillary tangles composed of hyperphosphorylated tau are major pathological hallmarks of Alzheimer's disease (AD). Elucidation of factors that modulate Aβ generation and tau hyperphosphorylation is crucial for AD intervention. Here, we identify a mouse gene Rps23r1 that originated through retroposition of ribosomal protein S23. We demonstrate that RPS23R1 protein reduces the levels of Aβ and tau phosphorylation by interacting with adenylate cyclases to activate cAMP/PKA and thus inhibit GSK-3 activity. The function of Rps23r1 is demonstrated in cells of various species including human, and in transgenic mice overexpressing RPS23R1. Furthermore, the AD-like pathologies of triple transgenic AD mice were improved and levels of synaptic maker proteins increased after crossing them with Rps23r1 transgenic mice. Our studies reveal a new target/pathway for regulating AD pathologies and uncover a retrogene and its role in regulating protein kinase pathways.