Manipulating host secreted protein gene expression: an indirect approach by HPV11/16 E6/E7 to suppress PBMC cytokine secretion.

Human papillomavirus (HPV) 11/16 E6/E7 proteins have been recognized to be pivotal in viral pathogenesis. This study sought to uncover the potential mechanisms of how HPV11/16 E6/E7-transfected keratinocytes inhibit cytokine secretion in peripheral blood mononuclear cells (PBMC). Upon co-culturing HPV11/16 E6/E7-transfected keratinocytes with PBMC in a non-contact manner, we observed a marked decrease in various cytokines secreted by PBMC. To determine if this suppression was mediated by specific common secreted factors, we conducted transcriptomic sequencing on these transfected cells. This analysis identified 53 common differentially secreted genes in all four HPV-transfected cells. Bioinformatics analysis demonstrated these genes were predominantly involved in immune regulation. Results from quantitative PCR (qPCR) and an extensive literature review suggested the downregulation of 12 genes (ACE2, BMP3, BPIFB1, CLU, CST6, CTF1, HMGB2, MMP12, PDGFA, RNASE7, SULF2, TGM2), and upregulation of 7 genes (CCL17, CCL22, FBLN1, PLAU, S100A7, S100A8, S100A9), may be crucial in modulating tumor immunity and combating pathogenic infections, with genes S100A8 and S100A9, and IL-17 signaling pathway being particularly noteworthy. Thus, HPV11/16 E6/E7 proteins may inhibit cytokine secretion of immune cells by altering the expression of host-secreted genes. Further exploration of these genes may yield new insights into the complex dynamics of HPV infection.

New resorcylic acid derivatives of Lysimachia tengyuehensis against MRSA and VRE by interfering with bacterial metabolic imbalance.

The abuse of antibiotics leads to the rapid spread of bacterial resistance, which seriously threatens human life and health. Now, 8 resorcylic acid derivatives, including 4 new compounds (1-4) were isolated from Lysimachia tengyuehensis by bio-guided isolation, and they inhibited both methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) (MIC = 4-8 µg/mL). Notably, 1 and 2 rapidly killed MRSA and VRE within 40 min without drug resistance in 20 days. Mechanically, they potently disrupted biofilm and cell membrane by interfering with bacterial metabolic imbalance. The structure-activity relationship (SAR) revealed that the lipophilic long carbon chains (C-5/C-6) and hydrophilic hydroxyl/carboxyl groups were essential for the anti-MRSA and VRE bioactivity. Additionally, they effectively recovered MRSA-infected skin wounds and VRE-infected peritoneal in vivo. Resorcylic acid derivatives showed significant anti-MRSA and VRE bioactivity in vitro and in vivo with potential application for the first time.

Nocardamine mitigates cellular dysfunction induced by oxidative stress in periodontal ligament stem cells.

BACKGROUND: The role of periodontal ligament stem cells (PDLSCs) in repairing periodontal destruction is crucial, but their functions can be impaired by excessive oxidative stress (OS). Nocardamine (NOCA), a cyclic siderophore, has been shown to possess anti-cancer and anti-bacterial properties. This study aimed to investigate the protective mechanisms of NOCA against OS-induced cellular dysfunction in PDLSCs. METHODS: The cytotoxicity of NOCA on PDLSCs was assessed using a CCK-8 assay. PDLSCs were then treated with hydrogen peroxide (H2O2) to induce OS. ROS levels, cell viability, and antioxidant factor expression were analyzed using relevant kits after treatment. Small molecule inhibitors U0126 and XAV-939 were employed to block ERK signaling and Wnt pathways respectively. Osteogenic differentiation was assessed using alkaline phosphatase (ALP) activity staining and Alizarin Red S (ARS) staining of mineralized nodules. Expression levels of osteogenic gene markers and ERK pathway were determined via real-time quantitative polymerase chain reaction (RT-qPCR) or western blot (WB) analysis. ß-catenin nuclear localization was examined by western blotting and confocal microscopy. RESULTS: NOCA exhibited no significant cytotoxicity at concentrations below 20 µM and effectively inhibited H2O2-induced OS in PDLSCs. NOCA also restored ALP activity, mineralized nodule formation, and the expression of osteogenic markers in H2O2-stimulated PDLSCs. Mechanistically, NOCA increased p-ERK level and promoted ß-catenin translocation into the nucleus; however, blocking ERK pathway disrupted the osteogenic protection provided by NOCA and impaired its ability to induce ß-catenin nuclear translocation under OS conditions in PDLSCs. CONCLUSIONS: NOCA protected PDLSCs against H2O2-induced OS and effectively restored impaired osteogenic differentiation in PDLSCs by modulating the ERK/Wnt signaling pathway.

The association of haemoglobin A1c variability with adverse outcomes in patients with atrial fibrillation prescribed anticoagulants.

AIMS: The association of haemoglobin A1c (HbA1c) variability with the risk of adverse outcomes in patients with atrial fibrillation (AF) prescribed anticoagulants remains unclear. This study aimed to evaluate the association of HbA1c variability with the risk of ischaemic stroke (IS)/systemic embolism (SE) and all-cause mortality among patients with non-valvular AF prescribed anticoagulants. METHODS AND RESULTS: Patients newly diagnosed with AF from 2013 to 2018 were included. Variability in HbA1c, indexed by the coefficient of variation (CV), was determined for those with at least three HbA1c measurements available from the time of study enrolment to the end of follow-up. To evaluate whether prevalent diabetes would modify the relationship between HbA1c variability and outcomes, participants were divided into diabetes and non-diabetes groups. The study included 8790 patients (mean age 72.7% and 48.5% female). Over a median follow-up of 5.5 years (interquartile range 5.2, 5.8), the incident rate was 3.74 per 100 person-years for IS/SE and 4.89 for all-cause mortality in the diabetes group. The corresponding incident rates in the non-diabetes group were 2.41 and 2.42 per 100 person-years. In the diabetes group, after adjusting for covariates including mean HbA1c, greater HbA1c variability was significantly associated with increased risk of IS/SE [hazard ratio (HR) = 1.65, 95% confidence interval (CI): 1.27-2.13) and all-cause mortality (HR = 1.24, 95% CI: 1.05-1.47) compared with the lowest CV tertile. A similar pattern was evident in the non-diabetes group (IS/SE: HR = 1.58, 95% CI: 1.23-2.02; all-cause mortality: HR = 1.35, 95% CI: 1.10-1.64). CONCLUSION: Greater HbA1c variability was independently associated with increased risk of IS/SE and all-cause mortality among patients with AF, regardless of diabetic status.

In patients with atrial fibrillation (AF), greater haemoglobin A1c (HbA1c) variability was independently associated with increased risk of ischaemic stroke/systemic embolism and all-cause mortality, regardless of diabetic status. The usefulness of HbA1c variability as a risk predictor is significant and could be integrated into the stratification of patients with AF. Even if HbA1c measurements are within standard guideline limits, patients with larger fluctuations in HbA1c level may be at higher risk of thromboembolism and death than patients with more stable HbA1c level.

A Non-invasive Blood Glucose Detection System Based on Photoplethysmogram with Multiple Near-infrared Sensors.

Recent advancements in non-invasive blood glucose detection have seen progress in both photoplethysmogram and multiple near-infrared methods. While the former shows better predictability of baseline glucose levels, it lacks sensitivity to daily fluctuations. Near-infrared methods respond well to short-term changes but face challenges due to individual and environmental factors. To address this, we developed a novel fingertip blood glucose detection system combining both methods. Using multiple light sensors and a lightweight deep learning model, our system achieved promising results in oral glucose tolerance tests. A total of 10 participants were involved in the study, each providing approximately 700 data segments of about 10 seconds each. With a root mean squared error of 0.242 mmol/L and 100% accuracy in zone A of the Parkes error grid, our approach demonstrates the potential of multiple near-infrared sensors for non-invasive glucose detection.

Formononetin Derivative for Osteoporosis by Simultaneous Regulating Osteoblast and Osteoclast.

Seven new formononetin derivatives (1-7) were designed and prepared from formononetin (phase II phytoestrogen). The derivatives 9-butyl-3-(4-methoxyphenyl)-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]oxazin-4-one (2) and 9-(furan-3-ylmethyl)-3-(4-methoxyphenyl)-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]oxazin-4-one (7) promoted significant osteoblast formation by modulating the BMP/Smad pathway. Compound 7 exhibited potent antiosteoclastogenesis activity in RANKL-induced RAW264.7 cells and ovariectomy (OVX)-induced osteoporosis in mice by regulation of the RANK/RANKL/OPG pathway. Compound 7 regulated osteoblast and osteoclast simultaneously and showed better effect than the well-known drug ipriflavone in vivo, suggesting 7 as a patented antiosteoporosis candidate.

Sanitization of hydroponic farming facilities in Singapore: what, why, and how.

This study performed microbial analysis of nutrient film technique (NFT) hydroponic systems on three indoor farms in Singapore (the "what"). To justify the necessity of sanitizing hydroponic systems, strong biofilm-forming bacteria were isolated from the facility and investigated for their influence on Salmonella colonization on polyvinyl chloride (PVC) coupons in hydroponic nutrient solutions (the "why"). Finally, sanitization solutions were evaluated with both laboratory-scale and field-scale tests (the "how"). As a result, the microbiome composition in NFT systems was found to be highly farm specific. The strong biofilm formers Corynebacterium tuberculostearicum C2 and Pseudoxanthomonas mexicana C3 were found to facilitate the attachment and colonization of Salmonella on PVC coupons. When forming dual-species biofilms, the presence of C2 and C3 also significantly promoted the growth of Salmonella (P < 0.05). Compared with hydrogen peroxide (H2O2) and sodium percarbonate (SPC), sodium hypochlorite (NaOCl) exhibited superior efficacy in biofilm removal. At 50 ppm, NaOCl reduced the Salmonella Typhimurium, C2, and C3 counts to <1 log CFU/cm2 within 12 h, whereas neither 3% H2O2 nor 1% SPC achieved this effect. In operational hydroponic systems, the concentration of NaOCl needed to achieve biofilm elimination increased to 500 ppm, likely due to the presence of organic matter accumulated during crop cultivation and the greater persistence of naturally formed multispecies biofilms. Sanitization using 500 ppm NaOCl for 12 h did not impede subsequent plant growth, but chlorination byproduct chlorate was detected at high levels in the hydroponic solution and in plants in the sanitized systems without rinsing. IMPORTANCE: This study's significance lies first in its elucidation of the necessity of sanitizing hydroponic farming systems. The microbiome in hydroponic systems, although mostly nonpathogenic, might serve as a hotbed for pathogen colonization and thus pose a risk for food safety. We thus explored sanitization solutions with both laboratory-scale and field-scale tests. Of the three tested sanitizers, NaOCl was the most effective and economical option, whereas one must note the vital importance of rinsing the hydroponic systems after sanitization with NaOCl.

Target organ damage in untreated hypertensive patients with primary aldosteronism.

An increased risk of target organ damage (TOD) has been reported in patients with primary aldosteronism (PA). However, there is relatively little related research on the correlation between the degree of TOD and those with and without PA in newly diagnosed hypertensive patients. The aim of this study was to assess the association between PA and TOD among patients with newly diagnosed hypertension. Newly diagnosed hypertensive patients were consecutively recruited from January 2015 to June 2020 at the University of Hong Kong-Shenzhen Hospital. Patients were stratified into those with and without PA. Data for left ventricular mass index (LVMI), carotid intima-media thickness (CIMT) and plaque, and microalbuminuria were systematically collected. A total of 1044 patients with newly diagnosed hypertension were recruited, 57 (5.5%) of whom were diagnosed with PA. Patients with PA had lower blood pressure, serum lipids, body mass index, and plasma renin activity and a higher incidence of hypokalemia than those without PA. In contrast, the prevalence of left ventricular hypertrophy, increased CIMT, and microalbuminuria was higher in patients with PA than in those without PA. Multivariable regression analysis demonstrated that PA was independently associated with increased LVMI, CIMT and microalbuminuria. Among patients with newly diagnosed hypertension, those with PA had more severe TOD, including a higher LVMI, CIMT and microalbuminuria, than those without PA. These findings emphasize the need for screening TOD in newly diagnosed hypertension due to underlying PA.

Norditerpenoid alkaloids from Aconitum refractum var. circinatum as autophagy inducers.

A total of twenty-two diterpenoid alkaloids, including ten unprecedented ones, namely refractines C-L, were isolated from the roots of Aconitum refractum (Finet et Gagnep.) Hand.-Mazz. Refractine C was the first example of a natural diterpenoid alkaloid wherein C-19 is linked to N position by an oxaziridine ring. Refractine L was a rare glycosidic diterpenoid alkaloid with fructofuranoside. Most of the isolated compounds obtained from a previous study were screened for their anti-inflammatory and myocardial protective activities. The autophagy-inducing effects of some of these compounds on RAW 264.7 cells were evaluated by assessing the expression of microtubule-associated protein 1 light chain 3 (LC3-II/LC3-I). Results revealed that some compounds exerted varying levels of inhibitory effects on the proliferative activity of RAW 264.7 cells.

Glycated Hemoglobin Variability Is Associated With Adverse Outcomes in Patients With Heart Failure Irrespective of Diabetic Status.

BACKGROUND: The effect of glycated hemoglobin (HbA1c) variability on adverse outcomes in patients with heart failure (HF) is unclear. We aim to investigate the predictive value of HbA1c variability on the risks of all-cause death and HF rehospitalization in patients with HF irrespective of their diabetic status. METHODS AND RESULTS: Using a previously validated territory-wide clinical data registry, HbA1c variability was assessed by average successive variability (ASV) or SD of all HbA1c measurements after HF diagnosis. Multivariable Cox proportional hazards models were used to estimate the adjusted hazard ratio (HR) and its corresponding 95% CI. A total of 65 950 patients with HF were included in the study. Over a median follow-up of 6.7 (interquartile range, 4.0-10.6) years, 34 508 patients died and 52 446 required HF rehospitalization. Every unit increment of variability in HbA1c was significantly associated with higher HF rehospitalization (HR ASV, 1.20 [95% CI, 1.18-1.23]) and all-cause death (HR ASV, 1.50 [95% CI, 1.47-1.53]). Diabetes significantly modified the association between HbA1c variability and outcomes (Pinteraction<0.001). HbA1c variability in patients with HF without diabetes conferred a higher risk of rehospitalization (HR ASV, 1.92 [95% CI, 1.70-2.17] versus HR ASV, 1.19 [95% CI, 1.17-1.21]), and all-cause death (HR ASV, 3.90 [95% CI, 3.31-4.61] versus HR ASV, 1.47 [95% CI, 1.43-1.50] compared with patients with diabetes). CONCLUSIONS: HbA1c variability is significantly associated with greater risk of rehospitalization and all-cause death in patients with HF, irrespective of their diabetic status. These observations were more pronounced in patients with HF without diabetes.

Prediabetes is associated with increased cardiac events in patients with cancer who are prescribed anthracyclines.

BACKGROUND: Prediabetes, which is a precedent of overt diabetes, is a known risk factor for adverse cardiovascular outcomes. Its impact on adverse cardiovascular outcomes in patients with cancer who are prescribed anthracycline-containing chemotherapy (ACT) is uncertain. The objective of this study was to evaluate the association of prediabetes with cardiovascular events in patients with cancer who are prescribed ACT. METHODS: The authors identified patients with cancer who received ACT from 2000 to 2019 from Clinical Data Analysis Reporting System of Hong Kong. Patients were divided into diabetes, prediabetes, and normoglycemia groups based on their baseline glycemic profile. The Primary outcome, a major adverse cardiovascular event (MACE), was the composite event of hospitalization for heart failure and cardiovascular death. RESULTS: Among 12,649 patients at baseline, 3997 had prediabetes, and 5622 had diabetes. Over median follow-up of 8.7 years, the incidence of MACE was 211 (7.0%) in the normoglycemia group, 358 (9.0%) in the prediabetes group, and 728 (12.9%) in the diabetes group. Compared with normoglycemia, prediabetes (adjusted hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.01-1.43) and diabetes (adjusted HR, 1.46; 95% CI, 1.24-1.70) were associated with an increased risk of MACE. In the prediabetes group, 475 patients (18%) progressed to overt diabetes and exhibited a greater risk of MACE (adjusted HR, 1.76; 95% CI, 1.31-2.36) compared with patients who remained prediabetic. CONCLUSIONS: In patients with cancer who received ACT, those who had prediabetes at baseline and those who progressed to diabetes at follow-up had an increased risk of MACE. The optimization of cardiovascular risk factor management, including prediabetes, should be considered in patients with cancer who are treated before and during ACT to reduce cardiovascular risk. PLAIN LANGUAGE SUMMARY: Patients with cancer who have preexisting diabetes have a higher risk of cardiovascular events, and prediabetes is often overlooked. In this study of 12,649 patients with cancer identified in the Clinical Data Analysis Reporting System of Hong Kong who were receiving treatment with anthracycline drugs, prediabetes was correlated with increased deaths from cardiovascular disease and/or hospitalizations for heart failure. Patients who progressed from prediabetes to diabetes within 2 years had an increased risk of combined hospitalization for heart failure and death from cardiovascular disease. These findings indicate the importance of paying greater attention to cardiovascular risk factors, including how prediabetes is managed, in patients who have cancer and are receiving chemotherapy with anthracyclines, emphasizing the need for surveillance, follow-up strategies, and consideration of prediabetes management in cancer care.

MicroRNA-298 determines the radio-resistance of colorectal cancer cells by directly targeting human dual-specificity tyrosine(Y)-regulated kinase 1A.

BACKGROUND: Radiotherapy stands as a promising therapeutic modality for colorectal cancer (CRC); yet, the formidable challenge posed by radio-resistance significantly undermines its efficacy in achieving CRC remission. AIM: To elucidate the role played by microRNA-298 (miR-298) in CRC radio-resistance. METHODS: To establish a radio-resistant CRC cell line, HT-29 cells underwent exposure to 5 gray ionizing radiation that was followed by a 7-d recovery period. The quantification of miR-298 levels within CRC cells was conducted through quantitative RT-PCR, and protein expression determination was realized through Western blotting. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and proliferation by clonogenic assay. Radio-induced apoptosis was discerned through flow cytometry analysis. RESULTS: We observed a marked upregulation of miR-298 in radio-resistant CRC cells. MiR-298 emerged as a key determinant of cell survival following radiation exposure, as its overexpression led to a notable reduction in radiation-induced apoptosis. Intriguingly, miR-298 expression exhibited a strong correlation with CRC cell viability. Further investigation unveiled human dual-specificity tyrosine(Y)-regulated kinase 1A (DYRK1A) as miR-298's direct target. CONCLUSION: Taken together, our findings underline the role played by miR-298 in bolstering radio-resistance in CRC cells by means of DYRK1A downregulation, thereby positioning miR-298 as a promising candidate for mitigating radio-resistance in CRC.

Microheater Chips with Carbon Nanotube Resistors.

The specific and excellent properties of the low-dimensional nanomaterials have made them promising building blocks to be integrated into microelectromechanical systems with high performances. Here, we present a new microheater chip for in situ TEM, in which a cross-stacked superaligned carbon nanotube (CNT) film resistor is located on a suspended SiNx membrane via van der Waals (vdW) interactions. The CNT microheater has a fast high-temperature response and low power consumption, thanks to the micro/nanostructure of the CNT materials. Moreover, the membrane bulging amplitude is significantly reduced to only ∼100 nm at 800 °C for the vdW interaction between the CNTs and the SiNx membrane. An in situ observation of the Sn melting process is successfully conducted with the assistance of a customized flexible temperature control system. The uniform wafer-scaled CNT films enable a high level of consistency and cost-effective mass production of such chips. The as-developed in situ chips, as well as the related techniques, hold great promise in nanoscience, materials science, and electrochemistry.

Structure optimizing of flavonoids against both MRSA and VRE.

Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) cause more than 100,000 deaths each year, which need efficient and non-resistant antibacterial agents. SAR analysis of 162 flavonoids from the plant in this paper suggested that lipophilic group at C-3 was crucial, and then 63 novel flavonoid derivatives were designed and total synthesized. Among them, the most promising K15 displayed potent bactericidal activity against clinically isolated MRSA and VRE (MICs = 0.25-1.00 µg/mL) with low toxicity and high membrane selectivity. Moreover, mechanism insights revealed that K15 avoided resistance by disrupting biofilm and targeting the membrane, while vancomycin caused 256 times resistance against MRSA, and ampicillin caused 16 times resistance against VRE by the same 20 generations inducing. K15 eliminated residual bacteria in mice skin MRSA-infected model (>99 %) and abdominal VRE-infected model (>92 %), which was superior to vancomycin and ampicillin.

Engineering van der Waals Contacts by Interlayer Dipoles.

Tuning the interfacial Schottky barrier with van der Waals (vdW) contacts is an important solution for two-dimensional (2D) electronics. Here we report that the interlayer dipoles of 2D vdW superlattices (vdWSLs) can be used to engineer vdW contacts to 2D semiconductors. A bipolar WSe2 with Ba6Ta11S28 (BTS) vdW contact was employed to exhibit this strategy. Strong interlayer dipoles can be formed due to charge transfer between the Ba3TaS5 and TaS2 layers. Mechanical exfoliation breaks the superlattice and produces two distinguished surfaces with TaS2 and Ba3TaS5 terminations. The surfaces thus have opposite surface dipoles and consequently different work functions. Therefore, all the devices fall into two categories in accordance with the rectifying direction, which were verified by electrical measurements and scanning photocurrent microscopy. The growing vdWSL family along with the addition surface dipoles enables prospective vdW contact designs and have practical application in nanoelectronics and nano optoelectronics.

ECGAN-Assisted ResT-Net Based on Fuzziness for OSA Detection.

OBJECTIVE: Growing attention has been paid recently to electrocardiogram (ECG) based obstructive sleep apnea (OSA) detection, with some progresses been made on this topic. However, the lack of data, low data quality, and incomplete data labeling hinder the application of deep learning to OSA detection, which in turn affects the overall generalization capacity of the network. METHODS: To address these issues, we propose the ResT-ECGAN framework. It uses a one-dimensional generative adversarial network (ECGAN) for sample generation, and integrates it into ResT-Net for OSA detection. ECGAN filters the generated ECG signals by incorporating the concept of fuzziness, effectively increasing the amount of high-quality data. ResT-Net not only alleviates the problems caused by deepening the network but also utilizes multi-head attention mechanisms to parallelize sequence processing and extract more valuable OSA detection features by leveraging contextual information. RESULTS: Through extensive experiments, we verify that ECGAN can effectively improve the OSA detection performance of ResT-Net. Using only ResT-Net for detection, the accuracy on the Apnea-ECG and private databases is 0.885 and 0.837, respectively. By adding ECGAN-generated data augmentation, the accuracy is increased to 0.893 and 0.848, respectively. CONCLUSION AND SIGNIFICANCE: Comparing with the state-of-the-art deep learning methods, our method outperforms them in terms of accuracy. This study provides a new approach and solution to improve OSA detection in situations with limited labeled samples.

Classical swine fever virus non-structural protein 5B hijacks host METTL14-mediated m6A modification to counteract host antiviral immune response.

Classical Swine Fever (CSF), caused by the Classical Swine Fever Virus (CSFV), inflicts significant economic losses on the global pig industry. A key factor in the challenge of eradicating this virus is its ability to evade the host's innate immune response, leading to persistent infections. In our study, we elucidate the molecular mechanism through which CSFV exploits m6A modifications to circumvent host immune surveillance, thus facilitating its proliferation. We initially discovered that m6A modifications were elevated both in vivo and in vitro upon CSFV infection, particularly noting an increase in the expression of the methyltransferase METTL14. CSFV non-structural protein 5B was found to hijack HRD1, the E3 ubiquitin ligase for METTL14, preventing METTL14 degradation. MeRIP-seq analysis further revealed that METTL14 specifically targeted and methylated TLRs, notably TLR4. METTL14-mediated regulation of TLR4 degradation, facilitated by YTHDF2, led to the accelerated mRNA decay of TLR4. Consequently, TLR4-mediated NF-κB signaling, a crucial component of the innate immune response, is suppressed by CSFV. Collectively, these data effectively highlight the viral evasion tactics, shedding light on potential antiviral strategies targeting METTL14 to curb CSFV infection.

Characterization of AST-001 non-clinical pharmacokinetics: A novel selective AKR1C3-activated prodrug in mice, rats, and cynomolgus monkeys.

AST-001 is a chemically synthesized inactive nitrogen mustard prodrug that is selectively cleaved to a cytotoxic aziridine (AST-2660) via aldo-keto reductase family 1 member C3 (AKR1C3). The purpose of this study was to investigate the pharmacokinetics and tissue distribution of the prodrug, AST-001, and its active metabolite, AST-2660, in mice, rats, and monkeys. After single and once daily intravenous bolus doses of 1.5, 4.5, and 13.5 mg/kg AST-001 to Sprague-Dawley rats and once daily 1 h intravenous infusions of 0.5, 1.5, and 4.5 mg/kg AST-001 to cynomolgus monkeys, AST-001 exhibited dose-dependent pharmacokinetics and reached peak plasma levels at the end of the infusion. No significant accumulation and gender differences were observed after 7 days of repeated dosing. In rats, the half-life of AST-001 was dose independent and ranged from 4.89 to 5.75 h. In cynomolgus monkeys, the half-life of AST-001 was from 1.66 to 5.56 h and increased with dose. In tissue distribution studies conducted in Sprague-Dawley rats and in liver cancer PDX models in female athymic nude mice implanted with LI6643 or LI6280 HepG2-GFP tumor fragments, AST-001 was extensively distributed to selected tissues. Following a single intravenous dose, AST-001 was not excreted primarily as the prodrug, AST-001 or the metabolite AST-2660 in the urine, feces, and bile. A comprehensive analysis of the preclinical data and inter-species allometric scaling were used to estimate the pharmacokinetic parameters of AST-001 in humans and led to the recommendation of a starting dose of 5 mg/m2 in the first-in-human dose escalation study.