A comprehensive investigation on modified cellulose nanocrystals and their films properties.

In this work, we aimed to tune cellulose nanocrystals (CNCs) properties by introducing different functional groups (aldehyde, carboxyl, silane, and ammonium groups) on the surface through different chemical modifications. These functional groups were obtained by combining: the periodate oxidation with TEMPO-oxidation, aminosylation or cationization. CNCs produced and their films were characterized to elucidate their performances. The results showed that the properties of obtained CNCs varied depending on the grafted functionalities on the surface. The results reveal that after each modification a colloidal stability is preserved. Interestingly, Periodate oxidation of cellulose nanocrystals results in film components that interact through intra- and intermolecular hemiacetals and lead to films with a tensile strength of 116 MPa compared to the pristine CNCs, in contrast the subsequent modifications led to lower tensile strength. Of note, remarkable thermal stability has been achieved after modifications reaching a maximum of 280 °C. The oxygen barrier properties of the films after modifications varied between 0.48 and 0.54 cm3µm/(m2d*kPa) at 50 % RH.

JMJD1C knockdown affects myeloid cell lines proliferation, viability, and gemcitabine/carboplatin-sensitivity.

OBJECTIVES: Chemotherapy-induced hematological toxicities are potentially life-threatening adverse drug reactions that vary between individuals. Recently, JMJD1C has been associated with gemcitabine/carboplatin-induced thrombocytopenia in non-small-cell lung cancer patients, making it a candidate marker for predicting the risk of toxicity. This study investigates if JMJD1C knockdown affects gemcitabine/carboplatin-sensitivity in cell lines. METHODS: Lentiviral transduction-mediated shRNA knockdown of JMJD1C in the cell lines K562 and MEG-01 were performed using shRNA#32 and shRNA#33. The knockdown was evaluated using qPCR. Cell proliferation, viability, and gemcitabine/carboplatin-sensitivity were subsequently determined using cell counts, trypan blue, and the MTT assay. RESULTS: ShRNA#33 resulted in JMJD1C downregulation by 56.24% in K562 and 68.10% in MEG-01. Despite incomplete knockdown, proliferation (reduction of cell numbers by 61-68%, day 7 post-transduction) and viability (reduction by 21-53%, day 7 post-transduction) were impaired in K562 and MEG-01 cells. Moreover, JMJD1C knockdown reduced the gemcitabine IC50-value for K562 cells (P < 0.01) and MEG-01 cells (P < 0.05) compared to scrambled shRNA control transduced cells. CONCLUSIONS: Our results suggest that JMJD1C is essential for proliferation, survival, and viability of K562 and MEG-01 cells. Further, JMJD1C also potentially affects the cells gemcitabine/carboplatin-sensitivity. Although further research is required, the findings show that JMJD1C could have an influential role for gemcitabine/carboplatin-sensitivity.

Genetic association of gemcitabine/carboplatin-induced leukopenia and neutropenia in non-small cell lung cancer patients using whole-exome sequencing.

OBJECTIVES: Gemcitabine/carboplatin treatment is known to cause severe adverse drug reactions which can lead to the need for reduction or cessation of chemotherapy. It would be beneficial to identify patients at risk of severe hematological toxicity in advance before treatment start. This study aims to identify genetic markers for gemcitabine/carboplatin-induced leukopenia and neutropenia in non-small cell lung cancer patients. MATERIAL AND METHODS: Whole-exome sequencing was performed on 215 patients. Association analysis was performed on single-nucleotide variants (SNVs) and genes, and the validation was based on an independent genome-wide association study (GWAS). Based on the association and validation analyses the genetic variants were then selected for and used in weighted genetic risk score (wGRS) prediction models for leukopenia and neutropenia. RESULTS: Association analysis identified 50 and 111 SNVs, and 12 and 20 genes, for leukopenia and neutropenia, respectively. Of these SNVS 20 and 19 were partially validated for leukopenia and neutropenia, respectively. The genes SVIL (p = 2.48E-06) and EFCAB2 (p = 4.63E-06) were significantly associated with leukopenia contain the partially validated SNVs rs3740003, rs10160013, rs1547169, rs10927386 and rs10927387. The wGRS prediction models showed significantly different risk scores for high and low toxicity patients. CONCLUSION: We have identified and partially validated genetic biomarkers in SNVs and genes correlated to gemcitabine/carboplatin-induced leukopenia and neutropenia and created wGRS models for predicting the risk of chemotherapy-induced hematological toxicity. These results provide a strong foundation for further studies of chemotherapy-induced toxicity.

The influence of ABCG2 polymorphism on erlotinib efflux in the K562 cell line.

Single nucleotide polymorphisms (SNPs) in the gene for multidrug resistance protein ABCG2, an erlotinib transporter, is a possible contributor to the interindividual variation observed in erlotinib pharmacokinetics and toxicity. Therefore, the aim was to study erlotinib efflux by ABCG2 wild-type (wt) and ABCG2 polymorphic variants in the K562 cell line. The chronic myeloid leukemia K562 cell line, neither expressing EGFR nor ABCG2, was transduced with vectors containing the ABCG2 wt, the SNPs: 34 G > A and 421 C > A, or with empty vector (K562/ve). ABCG2-expressing cells were enriched using magnetic sorting and the expression was verified using flow cytometry. Intracellular erlotinib concentrations were analyzed by LC-MS/MS after incubation with 1 µmol/L erlotinib for 60 minutes. All recombinant cell lines were confirmed carriers of the vector and expressed ABCG2. Differences in intracellular erlotinib concentrations were observed between K562/ve and K562 ABCG2 wt and between K562/ve and K562 ABCG2 34G > A (both P ≤ .001, one-way ANOVA with Tukey HSD post hoc test), indicating that the cell lines carrying ABCG2 wt and ABCG2 34G > A actively transports erlotinib out of the cells. The ABCG2 34G > A cell line had a higher transport capacity compared with ABCG2 wt after adjusting for ABCG2 expression (P = .024, t test). No differences were observed between K562/ve and K562 ABCG2 421 C > A. Genetic polymorphism in the ABCG2 gene has an influence on the transport of erlotinib which can contribute to the observed variation in erlotinib pharmacokinetics and toxicity.

Genes and variants in hematopoiesis-related pathways are associated with gemcitabine/carboplatin-induced thrombocytopenia.

Chemotherapy-induced myelosuppression, including thrombocytopenia, is a recurrent problem during cancer treatments that may require dose alterations or cessations that could affect the antitumor effect of the treatment. To identify genetic markers associated with treatment-induced thrombocytopenia, we whole-exome sequenced 215 non-small cell lung cancer patients homogeneously treated with gemcitabine/carboplatin. The decrease in platelets (defined as nadir/baseline) was used to assess treatment-induced thrombocytopenia. Association between germline genetic variants and thrombocytopenia was analyzed at single-nucleotide variant (SNV) (based on the optimal false discovery rate, the severity of predicted consequence, and effect), gene, and pathway levels. These analyses identified 130 SNVs/INDELs and 25 genes associated with thrombocytopenia (P-value < 0.002). Twenty-three SNVs were validated in an independent genome-wide association study (GWAS). The top associations include rs34491125 in JMJD1C (P-value = 9.07 × 10-5), the validated variants rs10491684 in DOCK8 (P-value = 1.95 × 10-4), rs6118 in SERPINA5 (P-value = 5.83 × 10-4), and rs5877 in SERPINC1 (P-value = 1.07 × 10-3), and the genes CAPZA2 (P-value = 4.03 × 10-4) and SERPINC1 (P-value = 1.55 × 10-3). The SNVs in the top-scoring pathway "Factors involved in megakaryocyte development and platelet production" (P-value = 3.34 × 10-4) were used to construct weighted genetic risk score (wGRS) and logistic regression models that predict thrombocytopenia. The wGRS predict which patients are at high or low toxicity risk levels, for CTCAE (odds ratio (OR) = 22.35, P-value = 1.55 × 10-8), and decrease (OR = 66.82, P-value = 5.92 × 10-9). The logistic regression models predict CTCAE grades 3-4 (receiver operator characteristics (ROC) area under the curve (AUC) = 0.79), and large decrease (ROC AUC = 0.86). We identified and validated genetic variations within hematopoiesis-related pathways that provide a solid foundation for future studies using genetic markers for predicting chemotherapy-induced thrombocytopenia and personalizing treatments.

Role of functional groups in the production of self-assembled microfibrillated cellulose hybrid frameworks and influence on separation mechanisms of dye from aqueous medium.

In this article, the role of surface ζ-potential, surface charge density of functional groups and available surface functional groups (-OH and -COO-) of microfibrillated cellulose (MFC) was explored in the production of self-assembled dimensional frameworks. Furthermore, 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) oxidation of MFC and in situ TEMPO functionalization of produced frameworks were performed. The effect of increased charge density of carboxylic groups (-COO-) and decrease in surface ζ-potential on binding of titanium dioxide (TiO2) and horseradish peroxidase (HRP) was investigated further. High binding of TiO2 and HRP was reported due to high density of carboxylic group (-COO-) on produced functional frameworks. Thereafter, a model water of Irgalite Violet NZ dye was targeted to understand the behavior of available functional groups and introduced surface ζ-potential of frameworks towards adsorption of dye. Possible size-exclusion of dye aggregates was also explored using neat-MFC frameworks. Photo-oxidation (TiO2) and enzymatic catalysis (HRP) were studied further and highly effective system towards dye degradation was reported. Lastly, this study has shown a well deliberated quantitative understanding of functional groups/their density responsible for the production of frameworks and separation of dye.

Processing-Structure-Property Correlation Understanding of Microfibrillated Cellulose Based Dimensional Structures for Ferric Ions Removal.

In this research article, wood based microfibrillated cellulose (MFC) was studied to gain a better understanding of the process of dependent network formation. Networking potential and obtained properties of the produced dimensional structures could be controlled using opted processing routes. The fabricated dimensional structure, using freeze-drying (FD) is a highly open and porous network (98% porosity) compared to slightly tight, dense and less porous network produced after pressing at 200kN (96% porosity), followed by vacuum-filtered (VF) networks (33% porosity). The porosity (17%) was further decreased when the casting (CS) method was used, further producing a highly dense and compressed network. High water flux (180.8 ± 11 L/m2h) of pressed freeze-dried (PFD) followed by vacuum-filtered (VF) (11.4 ± 1.9 L/m2h) and casting CS (0.7 ± 0.01 L/m2h) were calculated using device. Furthermore, increased water flux (1.4 fold) of Experimental Paper Machine (XPM) based structures was reported in comparison with CS structures. Pore-sized distribution and surface area were measured using Hg porosimetry; they showed an average pore size of 16.5 µm for FD, followed by PFD (8.2 µm) structures. A 27-fold decrease in average pore-size was observed for CS structure in comparison with the FD structures. Highest tensile strength (87 ± 21 MPa) was recorded for CS structures, indicating a more highly compacted network formation compared to VF (82 ± 19 MPa) and PFD (1.6 ± 0.06 MPa). Furthermore, an attempt was made to upscale the VF structures using traditional paper making approach on XMP. Improved tensile strength (73 ± 11 MPa) in machine produced structures is due to alignment of fibers towards machine direction compared to cross directional (43 ± 9 MPa) fractured structures as shown in our Scanning Electron Microscopy (SEM) analysis. Surface functionalization of MFC using enzyme (hexokinase) was performed to increase the adsorption efficiency towards ferric ions removal. All fabricated structures were further evaluated for Fe(iii) removal and it was summarized that charge densities of functional groups, produced ζ-potential and networking potential were dominating influential factors for adsorption fluctuation of ferric ions.

Erlotinib treatment induces cytochrome P450 3A activity in non-small cell lung cancer patients.

AIMS: Erlotinib is a tyrosine kinase inhibitor used in the treatment of non-small cell lung cancer highly metabolized by the cytochrome P450 (CYP) 3A. Hence, CYP3A4 activity might be a useful predictor of erlotinib pharmacokinetics in personalized medicine. The effect of erlotinib on CYP3A activity was therefore studied in non-small cell lung cancer patients. METHODS: The study included 32 patients scheduled for erlotinib monotherapy. CYP3A activity was assessed using quinine as a probe before and during erlotinib treatment. Plasma from blood samples drawn 16 hours post quinine administration were analysed using HPLC with fluorescence detection to determine the quinine/3-OH-quinine ratio. RESULTS: Matched samples, available from 13 patients, showed an induction of CYP3A activity (P = 0.003, Wilcoxon's signed rank test) after 2 months of treatment. The quinine/3-OH-quinine ratio decreased from 20.2 (± 13.4) at baseline to 11.0 (± 4.34). Single-point samples, available from 19 patients, supported the decrease in ratio (P = 0.007, Mann-Whitney U-test). Generally, females had a higher CYP3A activity both at baseline and after two months of treatment. Statistical analysis by gender also showed significant increase in CYP3A activity (males, n = 10, P = 0.001, and females, n = 22, P = 0.001). CONCLUSIONS: An induction of CYP3A activity was observed after 2 months of erlotinib treatment which was also seen when subdividing based on gender. It could be important to take this into consideration for patients co-administering other CYP3A-metabolizing drugs during erlotinib treatment and also makes it difficult to use baseline CYP3A activity to predict erlotinib pharmacokinetics.

In Vivo Cytochrome P450 3A Isoenzyme Activity and Pharmacokinetics of Imatinib in Relation to Therapeutic Outcome in Patients With Chronic Myeloid Leukemia.

BACKGROUND: Cytochrome P450 3A (CYP3A) isoenzyme metabolic activity varies between individuals and is therefore a possible candidate of influence on the therapeutic outcome of the tyrosine kinase inhibitor imatinib in patients with chronic myeloid leukemia (CML). The aim of this study was to investigate the influence of CYP3A metabolic activity on the plasma concentration and outcome of imatinib in patients with CML. METHODS: Forty-three patients with CML were phenotyped for CYP3A activity using quinine as a probe drug and evaluated for clinical response parameters. Plasma concentrations of imatinib and its main metabolite, CGP74588, were determined using liquid chromatography-mass spectrometry. RESULTS: Patients with optimal response to imatinib after 12 months of therapy did not differ in CYP3A activity compared to nonoptimal responders (quinine metabolic ratio of 14.69 and 14.70, respectively; P = 0.966). Neither the imatinib plasma concentration nor the CGP74588/imatinib ratio was significantly associated with CYP3A activity. CONCLUSIONS: The CYP3A activity does not influence imatinib plasma concentrations or the therapeutic outcome. These results indicate that although imatinib is metabolized by CYP3A enzymes, this activity is not the rate-limiting step in imatinib metabolism and excretion. Future studies should focus on other pharmacokinetic processes so as to identify the major contributor to patient variability in imatinib plasma concentrations.

Novel rapid liquid chromatography tandem masspectrometry method for vemurafenib and metabolites in human plasma, including metabolite concentrations at steady state.

A novel, rapid and sensitive liquid chromatography tandem-mass spectrometry method for quantification of vemurafenib in human plasma, that also for the first time allows for metabolite semi-quantification, was developed and validated to support clinical trials and therapeutic drug monitoring. Vemurafenib was analysed by precipitation with methanol followed by a 1.9 min isocratic liquid chromatography tandem masspectrometry analysis using an Acquity BEH C18 column with methanol and formic acid using isotope labelled internal standards. Analytes were detected in multireaction monitoring mode on a Xevo TQ. Semi-quantification of vemurafenib metabolites was performed using the same analytical system and sample preparation with gradient elution. The vemurafenib method was successfully validated in the range 0.5-100 µg/mL according to international guidelines. The metabolite method was partially validated owing to the lack of commercially available reference materials. For the first time concentration levels at steady state for melanoma patients treated with vemurafenib is presented. The low abundance of vemurafenib metabolites suggests that they lack clinical significance. Copyright © 2016 John Wiley & Sons, Ltd.

A validated liquid chromatography tandem mass spectrometry method for quantification of erlotinib, OSI-420 and didesmethyl erlotinib and semi-quantification of erlotinib metabolites in human plasma.

A liquid chromatography tandem mass spectrometry method was developed and validated for quantification of erlotinib and its metabolites in human plasma. The method is suitable for therapeutic drug monitoring and pharmacokinetic studies. The substances were extracted using protein precipitation, separated on a BEH XBridge C18 column (100 ×2.1 mm, 1.7 µm) by gradient elution at 0.7 mL/min of acetonitrile and 5 mM ammonium acetate. The concentration was determined using a Waters Xevo triple quadrupole mass spectrometer in a multi reaction monitoring mode. The total run time was 7 min. Deuterated erlotinib and OSI-597 were used as internal standard for erlotinib and its metabolites, respectively. Erlotinib, OSI-420 and didesmethyl erlotinib were quantified in the concentration range 25-5000 ng/mL, 0.5-500 ng/mL and 0.15-10 ng/mL, respectively. Precision and accuracy was <14% except for OSI-420 at LLOQ (17%). Extraction recovery was above 89%, 99% and 89% for erlotinib, OSI-420 and didesmethyl erlotinib, respectively. The human liver microsomes generated 14 metabolites, three of them not previously reported. Twelve metabolites were measured semi-quantitatively and validated with respect to selectivity, precision and stability.