Effects of total coumarins from Pileostegia tomentella on exosomal miRNA expression and angiogenesis in colorectal cancer cells.

CONTEXT: Pileostegia tomentella Hand. Mazz (Saxifragaceae) total coumarins (TCPT) show antitumour activity in colorectal cancer (CRC) with unknown mechanism of action. Tumour angiogenesis mediated by exosomes-derived miRNA exhibits the vital regulation of endothelial cell function in metastasis of CRC. OBJECTIVE: To investigate the effect of TCPT on exosomal miRNA expression and angiogenesis of CRC cells. MATERIALS AND METHODS: HT-29-derived exosomes were generated from human CRC cells (HT-29) or either treated with TCPT (100 µg/mL) for 24 h, followed by identification by transmission electron microscope, nanoparticle tracking analysis (NTA) and Western blot. Co-culture experiments for human umbilical vein endothelial cells (HUVECs) and exosomes were performed to detect the uptake of exosomes in HUVECs and its influence on HUVECs cells migration and lumen formation ability. Potential target miRNAs in exosomes were screened out by sequencing technology. Rescue assays of angiogenesis were performed by the transfecting mimics or inhibitors of targeted miRNA into HUVECs. RESULTS: HT-29-derived exosomes, after TCPT treatment (Exo-TCPT), inhibited the migration and lumen formation of HUVECs, reduced the expression levels of vascular marker (FLT-1, VCAM-1 and VEGFR-2) in HUVECs. Furthermore, the level of miR-375-3p was significantly upregulated in Exo-TCPT. Rescue assays showed that high expression of miR-375-3p in HUVECs inhibited migration and lumen formation abilities, which was consistent with the effects of Exo-TCPT, whereas applying miR-375-3p inhibitors displayed opposite effects. DISCUSSION AND CONCLUSION: TCPT exhibits anti-angiogenesis in CRC, possibly through upregulating exosomal miR-375-3p. Our findings will shed light on new target exosomes miRNA-mediated tumour microenvironment and the therapeutic application of Pileostegia tomentella in CRC.

Therapeutic drug monitoring of disease-modifying antirheumatic drugs in circulating leukocytes in immune-mediated inflammatory diseases.

The treatment of immune-mediated inflammatory diseases (IMIDs) is one of the main challenges of modern medicine. Although a number of disease-modifying antirheumatic drugs (DMARDs) are available, there is wide variability in clinical response to treatment among individuals. Therapeutic drug monitoring (TDM) has been proposed to optimize treatment; however, some patients still experience unsatisfactory outcomes, although the blood concentrations of drugs in these patients remain in the therapeutic range. One possible reason for this is that the conventional samples (e.g., whole blood or plasma) used in TDM may not accurately reflect drug concentrations or concentrations of their metabolites at the target site. Hence, more refined TDM approaches to guide clinical decisions related to dose optimization are necessary. Circulating leukocytes or white blood cells have a critical role in driving the inflammatory process. They are recruited to the site of injury, infection and inflammation, and the main target of small molecule DMARDs is within immune cells. Given this, assaying drug concentrations in leukocytes has been proposed to be of possible relevance to the interpretation of outcomes. This review focuses on the clinical implications and challenges of drug monitoring of DMARDs in peripheral blood leukocytes from therapeutic or toxicological perspectives in IMIDs.

Drug-Induced Liver Injury during Consolidation Therapy in Childhood Acute Lymphoblastic Leukemia as Assessed for Causality Using the Updated RUCAM.

Purpose: The presence of serious toxicities is a major problem in the treatment of childhood acute lymphoblastic leukemia (ALL). The objective of this research is to evaluate drug-induced liver injury (DILI) during consolidation therapy in childhood ALL. Methods: Clinical data of pediatric patients who received consolidation therapy between August 2012 and July 2018 were collected. Characteristics (incidences and patterns) of DILI at different stratifications were determined. Risks of DILI were evaluated using binary logistic regression analysis. Drug causality assessment was carried out by the updated Roussel Uclaf Causality Assessment Method (RUCAM). Results: Patients with high risk (HR) and standard risk (SR)/intermediate risk (IR) received 270 and 1539 courses of consolidation therapy, respectively; among these courses, 15 (5.6%) and 38 (2.5%) developed DILI. The occurrences of DILI in SR/IR patients were primarily associated with age (≤5.2 years), treatment course (≥5), and baseline serum parameters before treatment (cystatin C > 0.79 mg/L, albumin ≤45 g/L, and gamma-glutamyl transpeptidase (GGT) > 17 U/L). The ROC curve generated using the parameters assigned to specific values achieved an area under the curve (AUC) of 0.846 (95% CI 0.827-0.863) with a cutoff value of 3, and the sensitivity and specificity were 94.7% and 62.3%, respectively. For HR patients, a decrease in baseline albumin and elevation of baseline liver enzymes (GGT and aspartate aminotransferase) were observed in DILI cases compared with the non-DILI subjects. In the SR/IR group with DILI, the causality gradings for high-dose methotrexate (HD-MTX) were highly probable in 5 (13.2%) cases, probable in 31 (81.6%) cases, and possible in 2 (5.3%) cases. Among the DILI cases in HR-1, HR-2, and HR-3 groups, high causality gradings (probable + highly probable) were detected in "100% of HD-MTX + 57% of high-dose cytarabine (HD-Ara-C)," "100% of HD-MTX + 20% of pegylated asparaginase (PEG-ASP)," and "100% of HD-Ara-C + 33.3% of PEG-ASP," respectively. Conclusion: Incidence of DILI in HR patients was significantly higher than that in SR/IR patients. A number of potential risk factors were identified, among which the preexisting liver conditions were suggested as shared risk factors in all stratification groups. HD-MTX, HD-Ara-C, and PEG-ASP were the main causative agents of DILI. The knowledge generated from this study will be helpful for understanding characteristics of DILI during consolidation treatment in childhood ALL.

Ventilagolin Suppresses Migration, Invasion and Epithelial-Mesenchymal Transition of Hepatocellular Carcinoma Cells by Downregulating Pim-1.

OBJECTIVE: Inhibition of tumor metastasis is a useful strategy to improve the efficacy of cancer therapy. Ventilagolin, a natural 1, 4-naphthoquinone derivative extracted from Ventilago leiocarpa Benth, has shown promising antitumor effects in previous studies. However, the effects and underlying mechanisms of Ventilagolin against migration, invasion and epithelial-mesenchymal transition (EMT) of hepatocellular carcinoma (HCC) remain unclear. The present study has examined these effects and determined whether the proto-oncogene Pim-1 is involved. METHODS: The effects of Ventilagolin on migration, invasion, Pim-1 and EMT-related proteins (eg, E-cadherin, N-cadherin, Vimentin) expression were assessed by scratch wound healing, Transwell, qRT-PCR and Western blot assays, respectively. Pim-1 stably overexpressed HepG2 and SMMC-7721 cells were generated to explore whether Ventilagolin inhibited migration, invasion and EMT of HCC cells via regulating Pim-1. Subcutaneous xenograft tumor model in nude mice was established. Histopathological changes of tumor tissues were examined by H&E staining and expressions of Pim-1 and EMT-related proteins were detected by immunohistochemistry. RESULTS: Ventilagolin significantly (P < 0.01) reduced the expression of Pim-1 levels in HepG2 and SMMC-7721 cells. Compared with the control group, the migration and invasion abilities of Pim-1-overexpressing HepG2 and SMMC-7721 cells were significantly (P < 0.05, P < 0.01) enhanced, the expression of E-cadherin was decreased (P < 0.01), and the levels of N-cadherin and Vimentin were upregulated (P < 0.05, P < 0.01). Ventilagolin treatment effectively reversed these effects of Pim-1 overexpression. In vivo experiments showed that Ventilagolin could effectively suppress HCC tumor growth, downregulate Pim-1, N-cadherin and Vimentin expression, and upregulate E-cadherin expression. CONCLUSION: Ventilagolin suppresses HCC cell proliferation, migration and invasion and reverses EMT process by downregulating Pim-1, suggesting Ventilagolin is a potential therapeutic agent for treatment of HCC.

Myeloid neddylation targets IRF7 and promotes host innate immunity against RNA viruses.

Neddylation, an important type of post-translational modification, has been implicated in innate and adapted immunity. But the role of neddylation in innate immune response against RNA viruses remains elusive. Here we report that neddylation promotes RNA virus-induced type I IFN production, especially IFN-α. More importantly, myeloid deficiency of UBA3 or NEDD8 renders mice less resistant to RNA virus infection. Neddylation is essential for RNA virus-triggered activation of Ifna gene promoters. Further exploration has revealed that mammalian IRF7undergoes neddylation, which is enhanced after RNA virus infection. Even though neddylation blockade does not hinder RNA virus-triggered IRF7 expression, IRF7 mutant defective in neddylation exhibits reduced ability to activate Ifna gene promoters. Neddylation blockade impedes RNA virus-induced IRF7 nuclear translocation without hindering its phosphorylation and dimerization with IRF3. By contrast, IRF7 mutant defective in neddylation shows enhanced dimerization with IRF5, an Ifna repressor when interacting with IRF7. In conclusion, our data demonstrate that myeloid neddylation contributes to host anti-viral innate immunity through targeting IRF7 and promoting its transcriptional activity.

Antitumor Effects of Ethanol Extract from Ventilago leiocarpa Benth on Sarcoma 180 Tumor-Bearing Mice and Possible Immune Mechanism.

OBJECTIVE: To explore the antitumor effects of ethanol extract from Ventilago leiocarpa Benth (EEVLB) on sarcoma 180 (S180) tumor-bearing mice and the potential mechanism. METHODS: Sixty mice were randomly assigned to 6 groups according to a random number table: normal group, model group, 5-fluorouracil (5-FU) group (0.02 g·kg-1), and high-, medium-, low-dose EEVLB groups (100, 84, and 56 g of raw material·kg-1 body weight, respectively), with 10 mice each group. All treatments were given once daily for 10 consecutive days. Effects of EEVLB on inhibiting tumor growth and immune function in mice were evaluated among all groups after the treatments by detecting tumor inhibition rate, organ index, serum levels of interleukin (IL)-2, -6, -10, CD3+CD4+ T lymphocytes, CD4+/CD8+ ratio, caspase-3 and Bcl-2. RESULTS: EEVLB with different concentrations achieved inhibition of tumor growth in vivo, wherein the high-dose group showed the most significant reduction in tumor weight and increased apoptosis of tumor cells (P<0.05). In addition, both net weight gain and spleen index of mice showed uptrend in EEVLB treatment groups (P<0.05). Besides, serum levels of IL-2 and IL-6, percentages of CD3+CD4+ T lymphocytes and ratio of CD4+/CD8+ in peripheral blood were elevated in high- and medium-dose EEVLB groups compared with the model group (P<0.05). Also, upregulation of caspase-3 and downregulation of Bcl-2 were observed at protein levels in the high-dose EEVLB group (P<0.01). CONCLUSIONS: EEVLB exhibits promising antitumor activity in vivo. This effect might be due to activation of apoptotic signaling pathway, increase of cytokine levels and enhancement of immune function in tumor-bearing mice.

A Population Pharmacokinetics Model for Vancomycin Dosage Optimization Based on Serum Cystatin C.

BACKGROUND AND OBJECTIVES: Renal function has an important influence on the pharmacokinetics of vancomycin, and serum cystatin C (CysC) exhibits accurate predictive performance as a marker for renal function. This study aimed to develop a population pharmacokinetics (PopPK) model of vancomycin based on serum CysC in pediatric patients. In addition, vancomycin dosage was optimized with the area under the serum concentration-time curve over 24 h (AUC0-24)/minimum inhibitory concentration (MIC) ratio in the target range of 400-700 and the steady-state trough concentration (Css,trough). METHODS: Data were retrospectively obtained from pediatric patients aged 2-18 years who received vancomycin treatment for infection from January 2014 to June 2019. PopPK analysis and Monte Carlo simulations were conducted using nonlinear mixed effects model (NONMEM) software. RESULTS: A total of 220 children were included. Serum CysC and age were significant covariates affecting the pharmacokinetics of vancomycin. The final typical value of clearance was 2.25 L/h; the volume of distribution was 8.17 L. The average probability of target attainment values of AUC0-24/MIC ratios within 400-700 in the 2-7, 7-12, and 12-18 years age groups were 66.1%, 68.1% and 66.5%, respectively. The median Css,trough values of vancomycin for the 2-7, 7-12, and 12-18 years age groups were 7.49-11.84, 5.98-11.32, and 5.15-11.39 mg/L, respectively, and were highly correlated with AUC0-24/MIC ratios in the range of 400-700 when the MIC was 1 mg/L. CONCLUSIONS: The pharmacokinetic parameters for vancomycin in pediatric patients were estimated using a serum CysC model. The simulated dosages provide a reference for vancomycin therapy.

A population pharmacokinetic model of vancomycin for dose individualization based on serum cystatin C as a marker of renal function.

OBJECTIVES: This study aimed to establish a vancomycin population pharmacokinetics (PPK) model based on serum cystatin C and to optimize dosing for achieving targeted steady-state trough concentrations (Css ) of 10-15 and 15-20 mg/l. METHODS: Patients aged ≥18 years were prospectively enrolled. A vancomycin PPK model was built with glomerular filtration rate (GFR) as a renal covariate estimated by cystatin C. A new group of patients were used for external evaluation. PPK analysis and Monte Carlo simulations were performed using nonlinear mixed effect modelling programme. KEY FINDINGS: Two hundreds of patients with 514 samples were included. The final model was CL (L/h) = (5.07 × (GFR/105.5)0.524 × (AGE/48.5)-0.309 × (WT/60)0.491 ); V (l) = 46.3. Internal and external evaluations demonstrated good stability and predictability. The average probability of target attainment (PTA) of optimal dosing regimens for targeted Css achieving 10-15 and 15-20 mg/l were 51.2% and 40.6%, respectively. An average PTA ≥71% for targeted concentration of 10-20 mg/l was obtained. CONCLUSIONS: A vancomycin PPK model with cystatin C as the renal marker has good stability and predictability. The new proposed dosing regimens were predicted to achieve a good PTA.

Identification of Risk Factors in High-Dose Methotrexate-Induced Acute Kidney Injury in Childhood Acute Lymphoblastic Leukemia.

AIMS: Although high-dose methotrexate (HDMTX) is an effective means for the treatment of acute lymphoblastic leukemia (ALL), the development of renal dysfunction remains a significant management challenge. This study aimed to identify the key factors in HDMTX-induced acute kidney injury (AKI) in childhood ALL. METHODS: We retrospectively analyzed the clinical data in 1,329 courses of HDMTX treatment in 336 Chinese ALL children at the First Affiliated Hospital of Guangxi Medical University from September 2012 to November 2016. The clinical data were compared between the groups of children with development of AKI and those without. Risk factors were identified by multiple logistic regression analysis, and the diagnostic performance of plasma MTX concentration was evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: AKI was observed in 88 patients (26.2%) and 104 courses (7.8%). Binary logistic regression revealed that age (OR 1.349; p = 0.005), first HDMTX course (OR 1.767; p = 0.013), MTX dose per body surface area (BSA; OR 1.944; p = 0.015), and baseline serum total protein (OR 0.929; p = 0.021) significantly correlated with AKI. The area under the ROC for 48-h plasma MTX concentration was 0.890 (95% CI 0.850-0.930), and sensitivity and specificity values of the cut-off value were 78.8 and 90.4%, respectively. CONCLUSION: Increasing age, higher MTX dose per BSA, lower baseline serum protein, and first HDMTX course were significant risk factors for developing HDMTX-induced AKI in childhood ALL. The threshold of 48-h MTX plasma concentration is valuable for the prediction of HDMTX-induced AKI.

Population pharmacokinetics of vancomycin in Chinese pediatric patients
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OBJECTIVE: This study was conducted to develop a population pharmacokinetic (PopPK) model for vancomycin and to detect the significant covariates that influence the PopPKs to facilitate individualized therapy for Chinese pediatric patients. METHODS: Patients ≤ 10 years old who received vancomycin for ≥ 72 hours between 2007 and 2010 were analyzed using a nonlinear mixed-effects modeling approach (-NONMEM). A one-compartment model with first-order elimination was chosen to depict the data. Stepwise covariate modeling (SCM) was employed to detect significant covariates and obtain a final model. Internal validation methods, including bootstrapping and visual predictive checks (VPC), were applied to evaluate the robustness and predictive power of the final model. RESULTS: The analysis included 54 pediatric inpatients with 128 serum concentration samples. The mean age (range) was 124.30 (1.29 - 541.4) weeks, the mean weight was 10.36 (1.4 - 33.5) kg, and the mean baseline serum creatinine (Scr) level was 0.39 (0.15 - 1.32) mg/dL. Pneumonia was the most common indication for vancomycin therapy (33.33%), followed by bacteremia (25.93%), and meningitis (22.22%). A PopPK model of vancomycin in Chinese pediatric patients was developed. Postnatal age (PNA) significantly affected the vancomycin clearance (CL) of pediatric patients, and the influence was described using the sigmoid maximum effect (Emax) model. The effect of body weight (WT) on CL and volume of distribution (V) was investigated using an allometric scaling equation. The final model parameters were CL(L/h) = 11.75×[PNA0.4672/(PNA0.4672+33.30.4672)]×(WT/70)0.75×e0.362 and V(L) = 54.49×WT/70×e0.6711. The model evaluation results suggested robustness and good predictability of the final model. CONCLUSION: A PopPK model of vancomycin for Chinese pediatric patients was developed in this study. The significant covariates distinguished in the final model can provide helpful information to facilitate individualized therapy for Chinese pediatric patients.
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Initial dosage regimens of vancomycin for Chinese adult patients based on population pharmacokinetic analysis.

OBJECTIVE: To build a population pharmacokinetic model for Chinese adult patients and develop initial dosage regimens for patients with different degrees of renal function to achieve target steady-state trough concentrations in the range of 10 - 15 and 15 - 20 mg/l. METHOD: Data on serum vancomycin concentration was collected from a retrospective study including 72 Chinese adult patients. NONMEM was used to build the population pharmacokinetic model, and a one-compartment model was chosen to describe the vancomycin concentration-time profile. Internal evaluation by bootstrap and visual predictive check (VPC) was performed to evaluate the robustness and prediction of the final model. Monte Carlo simulations were conducted to develop initial dosage regimens to achieve target trough concentrations. RESULTS: A one-compartment model was built with creatinine clearance (CLcr) as the key covariate influencing drug clearance. The estimated drug clearance for patients with normal renal function (CLcr ≥ 80 ml/min) was 4.90 l/h, and 0.0654 × CLcr if CLcr was < 80 ml/min. The apparent volume of the central compartment was 47.76 l and no covariate was found to affect it. The results of bootstrap analysis were in agreement with the original parameters of the final model, and VPC of the final model demonstrated good predictability. Initial dosage regimens were developed based on the simulations of the population pharmacokinetic model. CONCLUSION: A one-compartment model fitted the retrospective data and CLcr had a significant effect on drug clearance. Initial dosage regimens for vancomycin were proposed to provide some help to individual therapy for Chinese adult patients with different renal functions.

Cellular Redox Status Regulates Emodin-Induced Radiosensitization of Nasopharyngeal Carcinoma Cells In Vitro and In Vivo.

Here, we report that regulation of cellular redox status is required for radiosensitization of nasopharyngeal carcinoma (NPC) cells by emodin. We evaluated emodin's radiosensitivity-enhancing ability by using NPC cells in vitro and xenografts in vivo. A clonogenic assay was performed to evaluate NPC cell survival and to determine dose modification factors. Flow cytometry, western blot analysis, and in vivo radiation-induced tumor regrowth delay assays were performed to characterize emodin's effects. Exposure of CNE-1 NPC cells to emodin enhanced their radiosensitivity. HIF-1α expression significantly increased under hypoxic conditions but did not change after treatment with emodin alone. Emodin downregulated mRNA and protein expression of HIF-1α. Cells exposed to radiation and emodin underwent significant cell cycle arrest at the G2/M phase. The percentage of apoptotic cells and reactive oxygen species (ROS) levels were significantly higher in the group exposed to emodin and radiation hypoxic group than in the other groups. Compared to the CNE-1 xenografts exposed to radiation alone, CNE-1 xenografts exposed to radiation with emodin showed significantly enhanced radiation effects. Our data suggest that emodin effectively enhanced the radiosensitivity of CNE-1 cells in vitro and in vivo. The mechanism appears to involve ROS generation and ROS-mediated inhibition of HIF-1α expression.