Hepatotoxicity of epidermal growth factor receptor - tyrosine kinase inhibitors (EGFR-TKIs).

Drug-induced liver injury (DILI) is one of the most frequently adverse reactions in clinical drug use, usually caused by drugs or herbal compounds. Compared with other populations, cancer patients are more prone to abnormal liver function due to primary or secondary liver malignant tumor, radiation-induced liver injury and other reasons, making potential adverse reactions from liver damage caused by anticancer drugs of particular concernduring clinical treatment process. In recent years, the application of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has changed the treatment status of a series of solid malignant tumors. Unfortunately, the increasing incidence of hepatotoxicitylimits the clinical application of EGFR-TKIs. The mechanisms of liver injury caused by EGFR-TKIs were complex. Despite more than a decade of research, other than direct damage to hepatocytes caused by inhibition of cellular DNA synthesis and resulting in hepatocyte necrosis, the rest of the specific mechanisms remain unclear, and few effective solutions are available. This review focuses on the clinical feature, incidence rates and the recent advances on the discovery of mechanism of hepatotoxicity in EGFR-TKIs, as well as rechallenge and therapeutic strategies underlying hepatotoxicity of EGFR-TKIs.

Discovery of a potent and selective PARP1 degrader promoting cell cycle arrest via intercepting CDC25C-CDK1 axis for treating triple-negative breast cancer.

PARP1 is a multifaceted component of DNA repair and chromatin remodeling, making it an effective therapeutic target for cancer therapy. The recently reported proteolytic targeting chimera (PROTAC) could effectively degrade PARP1 through the ubiquitin-proteasome pathway, expanding the therapeutic application of PARP1 blocking. In this study, a series of nitrogen heterocyclic PROTACs were designed and synthesized through ternary complex simulation analysis based on our previous work. Our efforts have resulted in a potent PARP1 degrader D6 (DC50 = 25.23 nM) with high selectivity due to nitrogen heterocyclic linker generating multiple interactions with the PARP1-CRBN PPI surface, specifically. Moreover, D6 exhibited strong cytotoxicity to triple negative breast cancer cell line MDA-MB-231 (IC50 = 1.04 µM). And the proteomic results showed that the antitumor mechanism of D6 was found that intensifies DNA damage by intercepting the CDC25C-CDK1 axis to halt cell cycle transition in triple-negative breast cancer cells. Furthermore, in vivo study, D6 showed a promising PK property with moderate oral absorption activity. And D6 could effectively inhibit tumor growth (TGI rate = 71.4 % at 40 mg/kg) without other signs of toxicity in MDA-MB-321 tumor-bearing mice. In summary, we have identified an original scaffold and potent PARP1 PROTAC that provided a novel intervention strategy for the treatment of triple-negative breast cancer.

Tetrahydrocurcumin Attenuates Polymyxin B Sulfate-Induced HK-2 Cells Apoptosis by Inhibiting Endoplasmic Reticulum Stress-Mediated PERK/eIF2α/ATF4/CHOP Signaling Pathway Axis.

The clinical application of polymyxin B (PMB) is limited by its nephrotoxic effects, making the reduction of PMB-induced nephrotoxicity has become a pressing concern for clinicians. Tetrahydrocurcumin (THC), known for its beneficial characteristics in biological functions, presents an attractive option for intervention therapy to mitigate PMB-induced nephrotoxicity. However, the underlying mechanism of how THC mitigates PMB-induced nephrotoxicity is still poorly understood. Here, we first evaluated the potential of THC intervention therapy to mitigate PMB-induced nephrotoxicity in an in vitro model of PMB-induced cell injury. Moreover, we demonstrated that THC effectively protected HK-2 cells from PMB-induced apoptosis by using cell counting kit-8 and flow cytometry assay. THC could also suppress PMB-induced endoplasmic reticulum (ER) stress via PERK/eIF2α/ATF4/CHOP pathway. In addition, using PERK inhibitor GSK2606414 to inhibit ER stress also alleviated PMB-induced apoptosis. Taken together, these findings provide novel insights that THC possesses the ability to alleviate PMB-induced nephrotoxicity by inhibiting the ER stress-mediated PERK/eIF2α/ATF4/CHOP axis, which sheds light on the benefits of THC as an intervention strategy to reduce PMB-induced nephrotoxicity, thus providing a potential avenue for improved clinical outcomes in patients receiving PMB treatment.

Fluorescent immunochromatography of vancomycin in plasma: A rapid and sensitive quantitative analysis.

Vancomycin (VAN) has a narrow therapeutic window and variable pharmacokinetic properties, which require timely monitoring of plasma concentration to adjust the dosage for better effectiveness. A sensitive and quantitative immunochromatographic method was developed to detect VAN in plasma. The linear response range of the method to detect plasma VAN was 1.25-50 µg/mL. The intra- and inter-assay coefficients were 4.68% and 8.81%, respectively, while the recovery was 89.10%-98.32%. The clinical comparative experiment results demonstrated a good correlation (r > 0.90) between the fluorescent immunochromatographic strip test and the mass spectrum. In this study, a simple, rapid, and high-sensitivity immunochromatographic method was established for detecting VAN, which helped establish the basis for further application of monitoring plasma concentration.

Metabolism and pharmacokinetic study of deuterated osimertinib.

Osimertinib is a highly selective third-generation irreversible inhibitor of epidermal growth factor receptor mutant, which can be utilized to treat non-small cell lung cancer. As the substrate of cytochrome P450 enzyme, it is mainly metabolized by the CYP3A enzyme in humans. Among the metabolites produced by osimertinib, AZ5104, and AZ7550, which are demethylated that is most vital. Nowadays, deuteration is a new design approach for several drugs. This popular strategy is deemed to improve the pharmacokinetic characteristics of the original drugs. Therefore, in this study the metabolism profiles of osimertinib and its deuterated compound (osimertinib-d3) in liver microsomes and human recombinant cytochrome P450 isoenzymes and the pharmacokinetics in rats and humans were compared. After deuteration, its kinetic isotope effect greatly inhibited the metabolic pathway that produces AZ5104. The plasma concentration of the key metabolite AZ5104 of osimertinib-d3 in rats and humans decreased significantly compared with that of the osimertinib. This phenomenon was consistent with the results of the metabolism studies in vitro. In addition, the in vivo results indicated that osimertinib-d3 had higher systemic exposure (AUC) and peak concentration (Cmax ) compared with the osimertinib in rats and human body.

Inhibition of TRIM32 by ibr-7 treatment sensitizes pancreatic cancer cells to gemcitabine via mTOR/p70S6K pathway.

Pancreatic cancer is one of the most notorious diseases for being asymptomatic at early stage and high mortality rate thereafter. However, either chemotherapy or targeted therapy has rarely achieved success in recent clinical trials for pancreatic cancer. Novel therapeutic regimens or agents are urgently in need. Ibr-7 is a novel derivative of ibrutinib, displaying superior antitumour activity in pancreatic cancer cells than ibrutinib. In vitro studies showed that ibr-7 greatly inhibited the proliferation of BxPC-3, SW1990, CFPAC-1 and AsPC-1 cells via the induction of mitochondrial-mediated apoptosis and substantial suppression of mTOR/p70S6K pathway. Moreover, ibr-7 was able to sensitize pancreatic cancer cells to gemcitabine through the efficient repression of TRIM32, which was positively correlated with the proliferation and invasiveness of pancreatic cancer cells. Additionally, knockdown of TRIM32 diminished mTOR/p70S6K activity in pancreatic cancer cells, indicating a positive feedback loop between TRIM32 and mTOR/p70S6K pathway. To conclude, this work preliminarily explored the role of TRIM32 in the malignant properties of pancreatic cancer cells and evaluated the possibility of targeting TRIM32 to enhance effectiveness of gemcitabine, thereby providing a novel therapeutic target for pancreatic cancer.

Bilirubin Reduces the Uptake of Estrogen Precursors and the Followed Synthesis of Estradiol in Human Placental Syncytiotrophoblasts via Inhibition and Downregulation of Organic Anion Transporter 4.

Estrogen biosynthesis in human placental trophoblasts requires the human organic anion transporter 4 (hOAT4)-mediated uptake of fetal derived precursors such as dehydroepiandrosterone-3-sulfate (DHEAS) and 16α-hydroxy-DHEA-S (16α-OH-DHEAS). Scant information is available concerning the contribution of fetal metabolites on the impact of placental estrogen precursor transport and the followed estrogen synthesis. This study substantiated the roles of bilirubin as well as bile acids (taurochenodeoxycholic acid, taurocholic acid, glycochenodeoxycholic acid, chenodeoxycholic acid) on the inhibition of hOAT4-mediated uptake of probe substrate 6-carboxylfluorescein and DHEAS in stably transfected hOAT4-Chinese hamster ovary cells, with the IC50 of 1.53 and 0.98 µM on 6-carboxylfluorescein and DHEAS, respectively, for bilirubin, and 90.2, 129, 16.4, and 12.3 µM on 6-CF for taurochenodeoxycholic acid, glycochenodeoxycholic acid, taurocholic acid, and chenodeoxycholic acid. Bilirubin (2.5-10 µM) concentration-dependently inhibited the accumulation of estradiol precursor DHEAS in human choriocarcinoma JEG-3 cells (reduced by 60% at 10 µM) and primary human trophoblast cells (reduced by 80% at 10 µM). Further study confirmed that bilirubin (0.625-2.5 µM) concentration-dependently reduced the synthesis and secretion of estradiol in primary human trophoblast cells, among which 2.5 µM of bilirubin reduced the synthesis of estradiol by 30% and secretion by 35%. In addition, immunostaining and Western blot results revealed a distinct downregulation of hOAT4 protein expression in primary human trophoblast cells pretreated with 2.5 µM of bilirubin. In conclusion, this study demonstrated that bilirubin reduced the uptake of estrogen precursors and the followed synthesis of estradiol in human placenta via inhibition and downregulation of organic anion transporter 4. SIGNIFICANCE STATEMENT: Fetal metabolites, especially bilirubin, were first identified with significant inhibitory effects on the hOAT4-mediated uptake of estrogen precursor DHEAS in hOAT4-CHO, JEG-3 and PHTCs. Bilirubin concentration-dependently suppressed the estradiol synthesis and secretion in PHTCs treated with DHEAS, which was synchronized with the decline of hOAT4 protein expression. Additionally, those identified bile acids exhibited a weaker inhibitory effect on the secretion of estradiol.

Decreased INPP5B expression predicts poor prognosis in lung adenocarcinoma.

BACKGROUND: Inositol Polyphosphate-5-Phosphatase B (INPP5B), a inositol 5-phosphatase, plays an important role in many biological processes through phosphorylating PI(4,5)P2 and/or PI(3,4,5)P3 at the 5-position. Nevertheless, little is known about its function and cellular pathways in tumors. This study aims to investigate the potential role of INPP5B as a diagnostic and prognostic biomarker for lung adenocarcinoma (LUAD), as well as its biological functions and molecular mechanisms in LUAD. METHODS: TCGA, GEO, CTPAC, and HPA datasets were used for differential expression analysis and pathological stratification comparison. The prognostic and diagnostic role of INPP5B was determined by Kaplan-Meier curves, univariate and multivariate Cox regression analysis, and receiver operating characteristics (ROC) curve analyses. The potential mechanism of INPP5B was explored through GO, KEGG, and GSEA enrichment analysis, as well as GeneMANIA and STRING protein-protein interaction (PPI) network. PicTar, PITA, and miRmap databases were used for exploring miRNA targeting INPP5B. In molecular biology experiments, immunohistochemical analyses and Western blot analyses were used to determine protein expression. Co-immunoprecipitation assay was used to detect protein-protein interactions. CCK8 assays and colony formation assays were used for the measurement of cell proliferation. Cell cycle was assessed by PI staining with flow cytometry. Cell migration was performed by Transwell assays and wound healing assays. RESULT: INPP5B was decreased in LUAD tissues compared with normal adjacent tissues. And the low expression of INPP5B was associated with late-stage pathological features. In addition, INPP5B was found to be a significant independent prognostic and diagnostic factor for LUAD patients. Hsa-miR-582-5p was predicted as a negative regulator of INPP5B mRNA expression. INPP5B was significantly correlated with the expression of PTEN and the activity of PI3K/AKT signaling pathways, as determined by enrichment analysis and PPI network. In vitro experiments partially confirmed the aforementioned findings. INPP5B could interact directly with PTEN. INPP5B overexpression inhibited LUAD cell proliferation and migration while downregulating the AKT pathway. CONCLUSION: Our results demonstrated that INPP5B could inhibit the proliferation and metastasis of LUAD cells. It could serve as a novel diagnostic and prognostic biomarker for LUAD patients. Trial registration LUAD tissues and corresponding para-cancerous tissues were collected from 10 different LUAD patients at Hangzhou First People's Hospital. The Ethics Committee of Hangzhou First People's Hospital has approved this study. (registration number: IIT-20210907-0031-01; registration date: 2021.09.13).

DYRK1A reinforces epithelial-mesenchymal transition and metastasis of hepatocellular carcinoma via cooperatively activating STAT3 and SMAD.

BACKGROUND: Hepatocellular carcinoma (HCC) accounts for the majority of liver cancer cases, while metastasis is considered the leading cause of HCC-related death. However, the currently available treatment strategies for efficient suppression of metastasis are limited. Therefore, novel therapeutic targets to inhibit metastasis and effectively treat HCC are urgently required. METHODS: Wound healing and Transwell assays were used to determine the migration and invasion abilities of HCC cells in vitro. Quantitative real-time PCR (qRT-PCR), protein array, immunofluorescence, and immunoprecipitation experiments were used to study the mechanism of DYRK1A-mediated metastasis. A tail vein metastasis model and H&E staining were utilized to assess metastatic potential in vivo. RESULTS: The results of the current study demonstrated that dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) was upregulated in HCC tissues compared with normal liver tissues. Additionally, the level of DYRK1A was increased in primary HCC tissues of patients with metastasis compared with those of patients without metastasis, and DYRK1A overexpression correlated with worse outcomes in liver cancer patients. Gain- and loss-of-function studies suggested that DYRK1A enhanced the invasion and migration abilities of HCC cells by promoting epithelial-mesenchymal transition (EMT). Regarding the promoting effect of DYRK1A on cell invasion, the results showed that DYRK1A was coexpressed with TGF-ß/SMAD and STAT3 signalling components in clinical tumour samples obtained from patients with HCC. DYRK1A also activated TGF-ß/SMAD signalling by interacting with tuberous sclerosis 1 (TSC1) and enhanced metastasis of HCC cells by activating STAT3. Furthermore, DYRK1A promoted EMT by cooperatively activating STAT3/SMAD signalling. CONCLUSION: Overall, the present study not only uncovered the promoting effect of DYRK1A on HCC metastasis and revealed the mechanism but also provided a new approach to predict and treat metastatic HCC.

Downregulation of the farnesoid X receptor promotes colorectal tumorigenesis by facilitating enterotoxigenic Bacteroides fragilis colonization.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second leading cause of cancer-related deaths in the world. The downregulation of farnesoid X receptor (FXR) is frequently founded in CRC patients. The current study found that the decreased expression of FXR in colorectal cancer leads to disorders of bile acids (BAs) metabolism. The altered BAs profile shaped distinct intestinal flora and positively regulated secretory immunoglobulin A (sIgA). The dual regulation of BAs and sIgA enhanced adhesion and biofilm formation of enterotoxigenic Bacteroides fragilis (ETBF), which has a colorectal tumorigenesis effect. The abundance of ETBF increased significantly in intestinal mucosa of colitis-associated cancer (CAC) mice, and finally promoted the development of colorectal cancer. This study suggests that downregulation of FXR in CRC results in BAs dysregulation, and BAs have strong effects on sIgA and gut flora. The elevated BAs concentration and altered gut microbiome are risk factors for CRC.

Effect of renal function on the risk of thrombocytopaenia in patients receiving linezolid therapy: A systematic review and meta-analysis.

AIMS: The association of renal function and linezolid-induced thrombocytopaenia (LIT) remains controversial. We performed a meta-analysis to determine whether impaired renal function is associated with an increased LIT risk. METHODS: We conducted a systematic search of PubMed, EMBASE and the Cochrane Library from inception to February 2021 for eligible studies evaluating the relationship between renal function and LIT. Indicators of renal function included renal impairment (RI), severe RI, haemodialysis status, creatinine clearance rate (Ccr) and estimated glomerular filtration rate (eGFR). Unadjusted and adjusted estimates and 95% confidence intervals (CIs) were calculated separately using a random-effect model. RESULTS: A total of 24 studies with 3580 patients were included in the meta-analysis. RI patients had an increased LIT risk compared to non-RI patients in both the unadjusted (OR 3.54; 95% CI 2.27, 5.54; I2 = 77.7%) and adjusted analyses (OR 2.51; 95% CI 1.82, 3.45; I2 = 17.9%). This association persisted in the subset of studies involving only patients receiving a fixed conventional dose (600 mg every 12 h) and other subgroup analyses by ethnicity, sample size and study quality. Moreover, the LIT risk was significantly higher in patients with severe RI and haemodialysis than in patients without severe RI and haemodialysis. The eGFR and Ccr were significantly lower in LIT patients than in non-LIT patients. CONCLUSIONS: Impaired renal function is associated with an increased risk of LIT. A reduced linezolid dose may be considered in RI patients at a low risk of treatment failure, ideally guided by therapeutic drug monitoring.

Incidence, risk factors and mortality of invasive pulmonary aspergillosis in patients with influenza: A systematic review and meta-analysis.

BACKGROUND: An increasing number of cases of invasive pulmonary aspergillosis (IPA) complicating influenza have been described. We performed a meta-analysis to estimate the incidence, risk factors and outcomes of IPA in patients with influenza. METHODS: A systematic search was conducted in the PubMed, EMBASE and Cochrane Library databases from their inception to 31 August 2021 for eligible studies. Data on the incidence and risk factors of and mortality due to IPA in influenza patients were pooled using a random-effects model. Sensitivity analyses restricted to severe influenza requiring intensive care unit (ICU) support and multiple subgroup analyses were performed. RESULTS: Fourteen studies involving 6024 hospitalised patients with influenza were included. IPA was estimated to occur in 10% of influenza patients, with a mortality rate of 52%. Similar incidence (11%) and mortality (54%) estimates for IPA were observed in the sensitivity analysis including severe cases requiring ICU support. Subgroup analysis by geographical location showed a similar IPA rate between European (10%) and non-European (11%) studies. The IPA rate in the subset of nine studies using the modified AspICU criteria was 13%. Most subgroup analyses showed ≥50% mortality in IPA patients. Several predictors for IPA susceptibility were identified, including male sex, smoking history, chronic lung disease, influenza A (H1N1), severe conditions requiring supportive therapy, corticosteroid use before admission, solid organ transplant and haematological malignancy. CONCLUSIONS: The IPA is common in individuals with severe influenza, and the prognosis is particularly poor. Influenza patients, especially those with high-risk factors, should be thoroughly screened for IPA.

Structural Characterization and Tumor Microvascular Inhibition Activity of Total Polysaccharide from Trametes sanguinea Lloyd.

Trametes sanguinea Lloyd total polysaccharide (TsLTP), was obtained by water extraction and ethanol precipitation from T. sanguinea. The structural characterization of TsLTP was elucidated mutually by TsL1 and TsL2, whose mass ratio is 1: 4. TsL1 is mainly composed of mannose, glucose, galactose, and fucose, and consist of T-Linked-Fucp, T-Linked-Manp, T-Linked-Galp, 1,4-Linked-Manp, 1,4-Linked-Glcp, 1,6-Linked-Manp, 1,6-Linked-Galp, 1,3,4-Linked-Glcp, 1,4,6-Linked-Glcp and 1,3,6-Linked-Glcp, with a molar ratio of 2.1: 1.7: 1.4: 1.0: 3.6: 2.0: 8.6: 1.3: 2.2: 1.2, while TsL2 mainly comprise of glucose and consist of T-Linked-Glcp, 1,3-Linked-Glcp, 1,4-Linked-Glcp and 1,4,6-Linked-Glcp, with a molar ratio of 1.0: 2.1: 7.6: 1.4. TsLTP exhibited strong inhibitory effects on the migration, invasion, and tube formation of human umbilical vein endothelial cells (iHUVECs) and chick embryo chorioallantoic membrane (CAM) angiogenesis, whereas no inhibitory activity on human TNBC cell lines. Taken together, our study suggests that TsLTP possesses a significant inhibition of tumor microvascular activity both in vitro and in vivo. The study of TsLTP with novel monosaccharide composition and tumor microvascular inhibitory activity might be a beneficial attempt for application of polysaccharide from the genus Trametes in tumor therapy.

Stimuli-Responsive Drug Delivery Systems for the Diagnosis and Therapy of Lung Cancer.

Lung cancer is the most commonly diagnosed cancer and the leading cause of cancer death worldwide. Numerous drugs have been developed to treat lung cancer patients in recent years, whereas most of these drugs have undesirable adverse effects due to nonspecific distribution in the body. To address this problem, stimuli-responsive drug delivery systems are imparted with unique characteristics and specifically deliver loaded drugs at lung cancer tissues on the basis of internal tumor microenvironment or external stimuli. This review summarized recent studies focusing on the smart carriers that could respond to light, ultrasound, pH, or enzyme, and provided a promising strategy for lung cancer therapy.

Determination of intracellular anlotinib, osimertinib, afatinib and gefitinib accumulations in human brain microvascular endothelial cells by liquid chromatography/tandem mass spectrometry.

RATIONALE: Brain metastases are a common complication in patients with non-small-cell lung cancer (NSCLC). Anlotinib hydrochloride is a novel multi-target tyrosine kinase inhibitor (TKI) exhibiting a superior overall response rate for brain metastases from NSCLC. The penetrability of anlotinib and three generations of epidermal growth factor receptor (EGFR) TKIs (osimertinib, afatinib and gefitinib) into brain microvascular endothelial cells (HBMECs) was compared. METHODS: A sensitive quantification method for the four TKIs was developed using liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS). Anlotinib and the three EGFR TKIs were separated on an ACQUITY BEH C18 column after a direct protein precipitation, and then analyzed using electrospray ionization in positive ion mode. The linearity, accuracy, precision, limit of quantification, specificity and stability were assessed. RESULTS: The four analytes could be efficiently quantified in a single run of 3.8 min. The validation parameters of all analytes satisfy the acceptance criteria of bioanalytical method guidelines. The calibration range was 0.2-200 ng mL-1 for anlotinib and gefitinib, 1-500 ng mL-1 for osimertinib and 1-200 ng mL-1 for afatinib. The penetration of anlotinib across HBMECs was comparable with that of afatinib and gefitinib but less than that of osimertinib. CONCLUSIONS: A sensitive LC/MS/MS method to simultaneously measure anlotinib, osimertinib, afatinib and gefitinib in cell extracts was successfully validated and applied to determine their uptake inside HBMECs, which could pave the way for future research on the role of anlotinib in NSCLC brain metastases.

Predictors of mortality in patients with coronavirus disease 2019: a systematic review and meta-analysis.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is associated with a high mortality rate, especially in patients with severe illness. We conducted a systematic review and meta-analysis to assess the potential predictors of mortality in patients with COVID-19. METHODS: PubMed, EMBASE, the Cochrane Library, and three electronic Chinese databases were searched from December 1, 2019 to April 29, 2020. Eligible studies reporting potential predictors of mortality in patients with COVID-19 were identified. Unadjusted prognostic effect estimates were pooled using the random-effects model if data from at least two studies were available. Adjusted prognostic effect estimates were presented by qualitative analysis. RESULTS: Thirty-six observational studies were identified, of which 27 were included in the meta-analysis. A total of 106 potential risk factors were tested, and the following important predictors were associated with mortality: advanced age, male sex, current smoking status, preexisting comorbidities (especially chronic kidney, respiratory, and cardio-cerebrovascular diseases), symptoms of dyspnea, complications during hospitalization, corticosteroid therapy and a severe condition. Additionally, a series of abnormal laboratory biomarkers of hematologic parameters, hepatorenal function, inflammation, coagulation, and cardiovascular injury were also associated with fatal outcome. CONCLUSION: We identified predictors of mortality in patients with COVID-19. These findings could help healthcare providers take appropriate measures and improve clinical outcomes in such patients.

The Ibr-7 derivative of ibrutinib radiosensitizes pancreatic cancer cells by downregulating p-EGFR.

BACKGROUND: Radiotherapy is one of the main treatments for pancreatic cancer, but radiation resistance limits its clinical application. As a result, novel therapeutic agents to improve radiosensitivity are urgently needed. This study aimed to investigate the effect of Ibr-7 (a derivative of ibrutinib) on the radiosensitivity of human pancreatic cancer cells. METHODS: The effect of Ibr-7 on pancreatic cancer cell proliferation was detected by CCK-8 assays. Radiosensitivity was assessed by clonogenic formation assays. Cell cycle and cell apoptosis were analysed by flow cytometry. DNA damage was evaluated by immunofluorescence analysis. The expression levels of PARP, Cleaved caspase 3, p-EGFR and EGFR were determined by western blot. RESULTS: Ibr-7 showed an anti-proliferative effect on PANC-1 and Capan2 cells in a dose- and time-dependent manner. Ibr-7 (2 µmol/L) enhanced the effect of radiation on PANC-1 and Capan2 cells. Further findings showed that this combination enhanced G2/M phase arrest and increased cell apoptosis. Additional molecular mechanism studies revealed that the expression of p-EGFR was decreased by Ibr-7 alone or in combination with radiation. Overexpression of p-EGFR reversed the cell apoptosis induced by Ibr-7 combined with radiation. Moreover, the expression of γ-H2AX was significantly decreased in the Ibr-7 plus radiation group. CONCLUSIONS: Our study indicated the potential application of Ibr-7 as a highly effective radiosensitizer for the treatment of pancreatic cancer cells.

Rapid quantification of tenofovir in umbilical cord plasma and amniotic fluid in hepatitis B mono-infected pregnant women during labor by ultra-performance liquid chromatography/tandem mass spectrometry.

RATIONALE: Tenofovir (TFV) is a first-line antiviral agent against hepatitis B virus (HBV) and is recommended for the prevention of mother-to-infant transmission of HBV. To study the distribution of TFV in umbilical cord plasma and amniotic fluid of HBV-infected pregnant women, a rapid and sensitive method for TFV determination was developed and validated. METHODS: The quantification method was developed using liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS). The analytes were separated on an Acquity UPLC HSS T3 column under gradient elution with methanol and 0.01% ammonia solution in 10 mM ammonium acetate/water. This is the first reported method for the determination of TFV using alkaline rather than acidic mobile phases. Linearity, accuracy, precision, limit of quantification, specificity and stability were assessed. RESULTS: Detection of TFV was achieved within 4 min. The calibration curves for TFV quantification showed excellent linearity in the range of 1-500 ng/mL. The intra- and interbatch precision and accuracy ranged from -4.35% to 6.92%. This method was successfully applied to determination of samples from 50 HBV mono-infected women undergoing tenofovir disoproxil fumarate therapy. The mean concentrations of TFV in the umbilical cord and amniotic fluid samples were 29.2 (4.6-86) and 470.9 (156-902) ng/mL, respectively, which showed a moderate positive correlation (r = 0.5299, P<0.001). CONCLUSIONS: A simple, rapid but sensitive bioanalytical method to determine TFV concentration in both umbilical cord plasma and amniotic fluid using LC/MS/MS was developed and applied to HBV-infected women during labor who were undergoing TDF therapy, which will help us understand the efficacy and safety of tenofovir during pregnancy.

A novel derivative of valepotriate inhibits the PI3K/AKT pathway and causes Noxa-dependent apoptosis in human pancreatic cancer cells.

Natural compound valepotriate exhibits inhibitory activity against a number of cancers, but the effect of valepotriate against pancreatic cancer is unclear, and the structure-activity relationship of valepotriate has not been characterized. In this study, we performed a structure-based similarity search and found 16 hit compounds. Among the 16 hits, (1S,6S,7R)-6-(acetyloxy)-1-[(3-methylbutanoyl)oxy]-4a,5,6,7a-tetrahydro-1H-spiro[cyclopenta[c]pyran-7,2'-oxiran]-4-ylmethyl 3-methylbutanoate (denoted as Amcp) exhibited superior anticancer activity against human pancreatic cancer BxPC-3 and SW1990 cells. The anti-proliferation activity of Amcp was validated in human pancreatic cancer BxPC-3 and SW1990 cells in vitro. Amcp more effectively induced apoptosis in BxPC-3 and SW1990 cells than gemcitabine. At a concentration of 15 µM, Amcp significantly suppressed the PI3K/AKT pathway and disrupted the mitochondrial membrane equilibrium through modulation of Noxa and Mcl-1 balance in both cell lines. Meanwhile, knockdown of Noxa substantially attenuated Amcp-induced reduction of cell viability and anti-apoptotic protein Mcl-1 level in BxPC-3 cells. In addition, Amcp showed synergistic anticancer effects when combined with gemcitabine in BxPC-3 cells. To conclude, this work not only suggests that Amcp possesses a dual-inhibitory activity towards PI3K/AKT pathway and Mcl-1, but also enlightens further development of bioactive valepotriate derivatives.

Application of a DSS colitis model in toxicologically assessing norisoboldine.

In standard nonclinical drug safety evaluation studies, limitations exist in predicting the clinical risk of a drug based only on data from healthy animals. To obtain more comprehensive toxicological information on norisoboldine (NOR), we conducted an exploratory study using C57BL/6 mice in addition to healthy mice as models of dextran sodium sulfate (DSS) colitis to evaluate the safety of NOR. The healthy mice and DSS colitis mice were exposed to 30 or 90 mg NOR/kg body weight or water for 15 days. Compared with the model control group, 90 mg/kg of NOR aggravated the symptoms and colonic lesions of the DSS colitis mice and even caused death in two animals. No significant adverse effects were observed in the healthy mice. These different toxic reactions to NOR in the healthy and DSS colitis mice indicate that NOR toxicity varies by status among animals and suggests that the DSS colitis mouse model may be more susceptible, accurate and comprehensive in evaluating the safety of NOR. In conclusion, 90 mg/kg of NOR may be safe for healthy mice but not for DSS colitis mice. The DSS colitis mouse model, with many features similar to those of human colitis patients, may be a novel choice to counteract the deficiencies of using healthy mice to evaluate the safety of anti-inflammatory bowel disease (IBD) drugs, and further research is required.