Simultaneous detection of myostatin-targeting monoclonal antibodies in dried blood spots and plasma using liquid chromatography-tandem mass spectrometry with field asymmetric ion mobility spectrometry.

Transforming growth factor-ß superfamily members, such as myostatin, growth/differentiation factor 11, and activin A, negatively regulate skeletal muscle mass. Inhibitors targeting these cytokines or activin receptor type IIB have the potential to treat muscular diseases and enhance physical performance. However, because of their effects on muscle mass and potential misuse, they are strictly prohibited in sports. Given the high potential for misuse as a doping agent in sports, effective analytical methods for these prohibited antibodies targeting these specific cytokines or their receptor are critically needed. In this study, we aimed to develop and validate a multitarget method to detect the prohibited transforming growth factor-ß superfamily-targeting monoclonal antibodies, such as landogrozumab, domagrozumab, and the activin receptor type IIB-targeting antibody, bimagrumab, in human plasma and dried blood spot (DBS) samples using liquid chromatography-tandem mass spectrometry. Antibodies were purified from both the DBS and plasma samples using protein G magnetic beads and field-asymmetric ion mobility spectrometry (FAIMS) to minimize interference, followed by liquid chromatography-tandem mass spectrometry analysis. The validation process included tests for specificity, selectivity, linearity, limit of detection (LOD), limit of identification, precision, recovery, carryover effect, and matrix effect. The LODs for the target antibodies were identical in both DBS and plasma samples at 0.1 µg/mL for landogrozumab heavy and light chains, as well as 0.25 µg/mL for the domagrozumab light chain and 0.25 µg/mL for the bimagrumab heavy chain. However, the heavy chain of domagrozumab exhibited an LOD of 0.5 µg/mL in DBS and 1 µg/mL in plasma. The analytical method demonstrated strong linearity, with R² values greater than 0.99 for both plasma and DBS, and no carryover effect. Precision (CV%) was below 15 % at both middle (1 or 5 µg/mL; specific to the heavy chain of domagrozumab in plasma) and high (10 µg/mL) concentrations and was less than 20 % at the LOD. The selectivity and specificity indicated no interference in the analysis of target mAbs in different blood samples. Recovery was 31.6-49.8 % for DBS and 51.4-85.3 % for plasma, with no significant matrix effect. This study provides an effective method for doping analysis and novel protein detection.

14K prolactin derived 14-mer antiangiogenic peptide targets bradykinin-/nitric oxide-cGMP-dependent angiogenesis.

Over the past few decades, VEGF-targeted antiangiogenic therapy for cancers has gained increasing attention. Nevertheless, there are still several limitations such as the potential resistance mechanisms arising in cancer cells against these therapies and their potential adverse effects. These limitations highlight the need for novel anti-angiogenesis molecules and better understanding of the mechanisms of tumor angiogenesis. In the present study, we investigated the antiangiogenic properties of a novel 14-mer antiangiogenic peptide (14-MAP) derived from N-terminal 14 kDa buffalo prolactin and characterized its mode of action. 14-MAP at the picomolar concentration inhibited VEGF- and bradykinin (an autacoid peptide expressed in vascular tissues in pathophysiology, BK)-stimulated endothelial nitric oxide (eNO) production, cell migration, and proliferation in endothelial cells and vessel development in the chick embryo. Although this peptide inhibited both VEGF- and BK-dependent angiogenic processes, its action was more pronounced in the latter. Moreover, the interference of 14-MAP with the eNO synthase (eNOS)-cyclic GMP pathway was also identified. A combination of a low dose of Avastin, a widely used drug targeting VEGF-dependent angiogenesis, and 14-MAP significantly reduced tumor size in an in vivo model of human colon cancer. Taken together, our results suggest that 14-MAP, a BK- and eNOS-dependent antiangiogenic peptide, might be useful for overcoming the limitation of VEGF-targeted antiangiogenic therapy in cancer patients. However, further studies will be required to further characterize its mode of action and therapeutic potential.

Optimizing Outcomes: Bevacizumab with Carboplatin and Paclitaxel in 5110 Ovarian Cancer Patients-A Systematic Review and Meta-Analysis.

BACKGROUND/OBJECTIVES: The study aimed to evaluate the efficacy and safety of incorporating bevacizumab into the combination therapy of carboplatin and paclitaxel for epithelial ovarian cancer and other clinical applications. METHODS: A systematic review was conducted following PRISMA guidelines using keyword searches in PubMed, Embase, Cochrane Library, CINAHL, ClinicalTrials.gov, and ICTRP until February 2024. Randomized controlled trials (RCTs) comparing carboplatin and paclitaxel with and without bevacizumab in ovarian cancer patients were included. Efficacy outcomes were overall survival (OS) and progression-free survival (PFS), as described by hazard ratios (HRs). Safety outcomes were analyzed with risk ratios (RRs) for 16 adverse events. RESULTS: Seven RCTs (n = 5110) were included. The combination with bevacizumab significantly improved PFS (HR: 0.73; 95% confidence interval: 0.58, 0.92; p = 0.008). The chemotherapy group receiving bevacizumab with carboplatin and paclitaxel showed a significantly higher incidence of hypertension, non-CNS bleeding, thromboembolic events, GI perforation, pain, and proteinuria. CONCLUSIONS: The combination of carboplatin, paclitaxel, and bevacizumab improves PFS compared to the regimen without bevacizumab, but it raises significant safety concerns. Clinical management should consider adverse event prevention by vigilantly monitoring blood pressure, signs and symptoms of bleeding, thromboembolism, GI perforation, and pain to balance the therapeutic benefits with the potential risks of this combination therapy.

Development of an Ephedrine In-House Matrix Reference Material and Its Application to Doping Analysis.

Biomatrix-based reference materials (RMs) improve the quality of laboratory test results by better representing actual samples. However, a matrix RM of ephedrine (EP) for threshold substances that require accurate analysis results has not yet been developed. Therefore, this study aimed to develop an in-house matrix RM for EP and subsequently apply it to analytical procedures. During the development of the in-house matrix EP RM, the system underwent homogeneity and stability studies. Additionally, it was subjected to interlaboratory comparison study in 11 laboratories, including 10 World Anti-Doping Agency (WADA)-accredited laboratories and our laboratory. Stability testing revealed no significant changes in the RM characteristics. For homogeneity, 10 random batches out of 200 were analyzed to confirm the uniformity within and between bottles. These results, combined with data from 11 laboratories, ensured retroactive validation. The traceability value of the in-house matrix EP RM was assigned as 9.83 ± 0.57 µg/mL (k = 2) by interlaboratory comparison studies and traceable uncertain evaluation. The feasibility of this method as a single calibration standard was confirmed in two laboratories. This substance is reliable and consistent for quality control during EP quantification, ensuring accurate and trustworthy outcomes. Consequently, this study establishes a framework and guidelines for producing in-house matrix RMs and serves as a reference for generating similar matrix RMs in other contexts.

Occurrence and health risk assessment of tropane alkaloids in cereal foods consumed in Korea.

Tropane alkaloids (TA) are natural toxins found in certain plants, including cereals, of which atropine and scopolamine are the main species of concern due to their acute toxicity. This study aimed to determine the occurrence of TA in cereal foods and assess the potential health risks associated with their consumption in Korea. TA levels were analyzed in 80 raw and 71 processed cereal samples, which were distributed throughout Korea in 2021, using ultra-performance liquid chromatography-tandem mass spectrometry. At least one of the six TA species, namely atropine, scopolamine, pseudotropine, tropinone, scopine, and 6-hydroxytropinone, was detected in 10 out of the 151 samples at levels ranging from 0.12 to 88.10 µg kg-1. Dietary exposure (mean, 0.23 ng kg-1 bw day-1) to atropine and scopolamine in the Korean population was estimated to be low across all age groups. This is despite considering worst-case scenarios using the total concentrations of atropine and scopolamine in a millet sample, both of which were detected, and 95th percentile consumption for consumers of millet only. Both the hazard index and margin of exposure methods indicated that the current levels of TA exposure from millet consumption were unlikely to pose significant health risks to the Korean population.

Population pharmacokinetics and model-based dosing optimization of teicoplanin in elderly critically ill patients with pneumonia.

PURPOSE: To evaluate the population pharmacokinetics and pharmacodynamics of teicoplanin in elderly critically ill patients with pneumonia for optimal dosages. METHODS: Fifteen critically ill patients (9 men) ≥ 60 years received teicoplanin 6 mg/kg for three doses followed by standard maintenance doses (6 mg/kg q24h) with renal dosing adjustment. Serial plasma samples from all patients were analyzed simultaneously by population pharmacokinetic modeling using NONMEM. Probability of target attainment (PTA) was calculated through Monte Carlo simulations for various dosing regimens to achieve adequate systemic exposures. RESULTS: The median (interquartile range, IQR) age, body mass index, and creatinine clearance (CrCl) was 75 (64-78) years, 22.5 (20.8-25.4) kg/m2, and 64 (47-106) mL/min, respectively. The median (IQR) peak and trough concentration was 46.5 (42.7-51.0) and 8.7 (7.2-9.5) mg/L. The population pharmacokinetic model showed slower clearance (CL) and larger peripheral volume of distribution (V2) in patients with reduced CrCl: CL (L/h) = 0.629 × (CrCl/64)0.656, V2 (L) = 55.7 × (CrCl/64)-0.665. Model-based simulations showed PTAs ≥85% only for higher-dose regimens (12 mg/kg) up to an MIC of 0.5 mg/L. CONCLUSIONS: Standard teicoplanin dosages for pneumonia may provide inadequate systemic exposures in elderly critically ill patients. High-dose regimens should be considered as empiric therapy or for less susceptible pathogens.

BEAR: A Novel Virtual Screening Method Based on Large-Scale Bioactivity Data.

Data-driven drug discovery exploits a comprehensive set of big data to provide an efficient path for the development of new drugs. Currently, publicly available bioassay data sets provide extensive information regarding the bioactivity profiles of millions of compounds. Using these large-scale drug screening data sets, we developed a novel in silico method to virtually screen hit compounds against protein targets, named BEAR (Bioactive compound Enrichment by Assay Repositioning). The underlying idea of BEAR is to reuse bioassay data for predicting hit compounds for targets other than their originally intended purposes, i.e., "assay repositioning". The BEAR approach differs from conventional virtual screening methods in that (1) it relies solely on bioactivity data and requires no physicochemical features of either the target or ligand. (2) Accordingly, structurally diverse candidates are predicted, allowing for scaffold hopping. (3) BEAR shows stable performance across diverse target classes, suggesting its general applicability. Large-scale cross-validation of more than a thousand targets showed that BEAR accurately predicted known ligands (median area under the curve = 0.87), proving that BEAR maintained a robust performance even in the validation set with additional constraints. In addition, a comparative analysis demonstrated that BEAR outperformed other machine learning models, including a recent deep learning model for ABC transporter family targets. We predicted P-gp and BCRP dual inhibitors using the BEAR approach and validated the predicted candidates using in vitro assays. The intracellular accumulation effects of mitoxantrone, a well-known P-gp/BCRP dual substrate for cancer treatment, confirmed nine out of 72 dual inhibitor candidates preselected by primary cytotoxicity screening. Consequently, these nine hits are novel and potent dual inhibitors for both P-gp and BCRP, solely predicted by bioactivity profiles without relying on any structural information of targets or ligands.

Comparison between laparoscopic pylorus-preserving gastrectomy and laparoscopic distal gastrectomy for overweight patients with early gastric cancer.

Purpose: Laparoscopic pylorus-preserving gastrectomy (LPPG) has a nutritional advantage over laparoscopic distal gastrectomy (LDG), however, may be less beneficial in overweight patients in terms of weight loss. The purpose of this study was to compare LPPG and LDG in overweight patients with early gastric cancer. Methods: Clinicopathologic data of overweight patients (body mass index [BMI], ≥25 kg/m2) who underwent LPPG (n = 63) or LDG (n = 183) in 2016-2018 were retrospectively reviewed. In the LDG group, patients with Billroth-II anastomosis were separately grouped (LDG B-II, n = 66). Changes in BMI, hemoglobin, albumin, and total protein were compared among groups. Results: Changes in BMI were not significant different among groups. The LPPG group had significantly higher albumin than the LDG group at postoperative 6 months and 1 year. The LPPG group had higher total protein than the LDG group at postoperative 2 years. The LPPG group had a higher complication rate of Clavien-Dindo classification III or higher (20.6%) than the LDG group (8.2%, P = 0.007). However, after excluding pyloric stenosis, there was no significant difference among groups (LPPG vs. LDG, P = 0.290; LPPG vs. LDG B-II, P = 0.921). Conclusion: LPPG and LDG groups showed similar weight loss. However, the LPPG group had higher albumin and protein levels than the LDG group of overweight patients. Thus, it is not necessary to select LDG only for weight loss. LPPG may be selected as one option due to its potential nutritional benefit when pyloric stenosis is properly managed.

NOAEL cancer therapy: a tumor targetable docetaxel-inorganic polymer nanohybrid prevents drug-induced neutropenia.

To date, cancer therapies largely consist of five pillars: surgery, radiation, chemotherapy, targeted therapy, and immunotherapy. Still, researchers are trying to innovate the current cancer therapies to pursue an ideal one without side effects. For developing such a therapy, we designed a chemically well-defined route to a PEG- and docetaxel (DTX)-conjugated inorganic polymer, polyphosphazene, named "polytaxel (PTX)" with a prolonged blood circulation time and tumor localization. Here, we conducted the proof-of-concept study of the ideal therapy in orthotopic and xenograft pancreatic cancer models. We found that the average tumor inhibition rates of PTX were similar to those of DTX without any DTX toxicity-related side effects, such as neutropenia and weight loss. In conclusion, PTX met the requirements of an ideal anticancer drug with high anticancer efficacy and 100% survival rate. PTX is expected to replace any existing anticancer therapies in clinical practice.

COVID-19 drugs: potential interaction with ATP-binding cassette transporters P-glycoprotein and breast cancer resistance protein.

Background: The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2, has resulted in acute respiratory distress, fatal systemic manifestations (extrapulmonary as well as pulmonary), and premature mortality among many patients. Therapy for COVID-19 has focused on the treatment of symptoms and of acute inflammation (cytokine storm) and the prevention of viral infection. Although the mechanism of COVID-19 is not fully understood, potential clinical targets have been identified for pharmacological, immunological, and vaccinal approaches. Area covered: Pharmacological approaches including drug repositioning have been a priority for initial COVID-19 therapy due to the time-consuming nature of the vaccine development process. COVID-19 drugs have been shown to manage the antiviral infection cycle (cell entry and replication of proteins and genomic RNA) and anti-inflammation. In this review, we evaluated the interaction of current COVID-19 drugs with two ATP-binding cassette transporters [P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP)] and potential drug-drug interactions (DDIs) among COVID-19 drugs, especially those associated with P-gp and BCRP efflux transporters. Expert opinion: Overall, understanding the pharmacodynamic/pharmacokinetic DDIs of COVID-19 drugs can be useful for pharmacological therapy in COVID-19 patients.

Discovery of a NADPH oxidase inhibitor, (E)-3-cyclohexyl-5-(4-((2-hydroxyethyl)(methyl)amino)benzylidene)-1-methyl-2-thioxoimidazolidin-4-oneone, as a novel therapeutic for Parkinson's disease.

Several lines of evidence indicated that generation of NADPH oxidase (Nox)-mediated reactive oxygen species are associated with neuronal inflammation, leading to Parkinson's disease (PD). Novel benzylidene-1-methyl-2-thioxoimidazolidin-one derivatives as Nox inhibitors were designed and synthesized in order to increase blood-brain barrier (BBB) permeability to target Nox in brain cells. In lucigenin chemiluminescence assay, eight compounds showed excellent inhibition activity against NADPH oxidases and parallel artificial membrane permeability assay (PAMPA) identified compound 11 with high passive permeability. To validate the effect of compound 11 on neuronal inflammation, we tested the regulatory activity of compound 11 in lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines in BV-2 microglial cells and LPS-mediated microglial migration. Treatment of BV2 cells with compound 11 resulted in suppressed production of pro-inflammatory cytokines and migration activity of BV2 cells in response to LPS. To evaluate the therapeutic efficacy of compound 11 in PD animal model, compound 11 was applied to MPTP-induced PD mouse model. Oral administration of compound 11 (30 mg/kg/daily, 4 weeks) into the mice resulted in suppression of dopaminergic neuronal death in substantia nigra (SN) and in striatum as well as inhibition of microglial migration into SN. These results implicate compound 11 as a novel therapeutic agent for the treatment of PD.

Discovery of (E)-3-(3-((2-Cyano-4'-dimethylaminobiphenyl-4-ylmethyl)cyclohexanecarbonylamino)-5-fluorophenyl)acrylic Acid Methyl Ester, an Intestine-Specific, FXR Partial Agonist for the Treatment of Nonalcoholic Steatohepatitis.

A series of fexaramine analogs were synthesized and evaluated to develop an intestine-selective/specific FXR partial agonist. Introduction of both a CN substituent at the C-2 in the biphenyl ring and a fluorine at the C-5 in the aniline ring in fexaramine markedly increased FXR agonistic activity. 27c showed 53 ± 3% maximum efficacy relative to GW4064 in an FXR agonist assay. A substantial amount of 27c was absorbed in the intestine after oral administration in rats, and then it was rapidly metabolized to inactive carboxylic acid 44 by serum esterases. In CDAHFD-fed mice, oral administration of 27c strongly induced multiple intestinal FXR target genes, FGF15, SHP, IBABP, and OST-α, but failed to activate SHP in the liver. 27c significantly reduced the liver fibrogenesis area, hepatic fibrosis markers, and serum level of AST. Rational optimization of fexaramine has led to the identification of an intestine-specific FXR partial agonist 27c.

Occurrence and risk assessment of sterigmatocystin in agricultural products and processed foods in Korea.

Sterigmatocystin (STC), a carcinogenic mycotoxin, is known to be produced during the biosynthetic pathway of aflatoxin B1. STC in various foods was determined by LC-MS/MS and its risks were assessed. The analytical method was validated in different food categories, and the performance was acceptable based on the criteria of AOAC. A total 1,135 samples (613 agricultural products and 522 processed foods) were analysed, and STC was detected in 46 samples, indicating a detection rate of 4.1%. STC was found in the range of 0.08-10.07 ng/g, and the detection rates of STC were 3.9% in agricultural products and 4.2% in processed foods. The exposure to STC by average consumption of foods was estimated to 0.09 ng/kg b.w./day. The margin of exposure (MOE) approach was applied to assess the risk of STC, and MOE for the whole population was over 1 × 106. Exposure to STC from the consumption of foods distributed in Korea is unlikely to cause human health problems.

Microwave-assisted digestion method using diluted nitric acid and hydrogen peroxide for the determination of major and minor elements in milk samples by ICP-OES and ICP-MS.

A novel method for microwave-assisted digestion of milk samples using diluted HNO3and H2O2 with a single reaction chamber was developed for elemental analysis by ICP-based techniques. The optimal conditions for digestion were 0.25 g of sample mass, 6 mL of 0.1 molL-1HNO3and 2 mL of 30% H2O2 at 250 ℃ and 160 bar. The optimized procedure resulted in low residual carbon content and residual acidity of 260 mgL-1 and 0.06 mol L-1, respectively. The limits of detection ranged from 0.286Õ¸g g-1(Ca) to 82.990Õ¸g g-1(Fe). In addition, the proposed method was considered an excellent green analysis method with a final score of 87 based on the analytical Eco-Scale. Finally, the method was validated and applied to the determination of Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sb, Se, and Zn in milk samples from South Korea.

Anticancer Activity of Periplanetasin-5, an Antimicrobial Peptide from the Cockroach Periplaneta americana.

Cockroaches live in places where various pathogens exist and thus are more likely to use antimicrobial compounds to defend against pathogen intrusions. We previously performed an in silico analysis of the Periplaneta americana transcriptome and detected periplanetasin-5 using an in silico antimicrobial peptide prediction method. In this study, we investigated whether periplanetasin-5 has anticancer activity against the human leukemia cell line K562. Cell growth and survival of K562 cells treated with periplanetasin-5 were decreased in a dose-dependent manner. By using flow cytometric analysis, acridine orange/ethidium bromide (AO/EB) staining and DNA fragmentation, we found that periplanetasin-5 induced apoptotic and necrotic cell death in leukemia cells. In addition, these events were associated with increased levels of the pro-apoptotic proteins Fas and cytochrome c and reduced levels of the anti-apoptotic protein Bcl-2. Periplanetasin-5 induces the cleavage of pro-caspase-9, pro-caspase-8, pro-caspase-3, and poly (ADP-ribose) polymerase (PARP). The above data suggest that periplanetasin-5 induces apoptosis via both the intrinsic and extrinsic pathways. Moreover, caspase-related apoptosis was further confirmed by using the caspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (Z-VAD-FMK), which reversed the periplanetasin-5-induced reduction in cell viability. In conclusion, periplanetasin-5 caused apoptosis in leukemia cells, suggesting its potential utility as an anticancer therapeutic agent.

Antiseptic effect of antimicrobial peptide psacotheasin 2 derived from the yellow-spotted longicorn beetle (Psacothea hilaris).

Given the challenges posed by antibiotic resistant microbes and the high mortality rate associated with sepsis, there is an urgent need to develop novel peptide antibiotics that exhibit both antimicrobial and anti-inflammatory activities. Herein, we evaluated antimicrobial activity and anti-inflammatory activity of psacotheasin 2, one of the antimicrobial peptide candidates identified previously using an in silico analysis on the transcriptome of Psacothea hilaris. In addition to exhibiting antimicrobial activities against microorganisms without inducing hemolysis, psacotheasin 2 also decreased the nitric oxide production in lipopolysaccharide (LPS)-induced Raw264.7 cells. Moreover, ELISA and western blot analysis revealed that psacotheasin 2 reduced the expression levels of pro-inflammatory enzymes such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Further, we found that psacotheasin 2 markedly reduced the expression levels of pro-inflammatory cytokines (IL-6 and IL-1ß) by regulating mitogen-activated protein kinases (MAPKs) and nuclear factor-kB (NF-kB) signaling in LPS-induced Raw264.7 cells. We also confirmed that the binding of psacotheasin 2 to bacterial cell membranes occurs via a specific interaction with LPS. In mouse models of LPS-induced shock, psacotheasin 2 significantly enhanced the survival rate and recovered weight by attenuating pro-inflammatory cytokines. Thus, psacotheasin 2 could be a promising candidate as a peptide antiseptic agent.

Dual Inhibition of P-gp and BCRP Improves Oral Topotecan Bioavailability in Rodents.

P-glycoprotein (P-gp) inhibition has been studied to overcome multidrug resistance in cancer chemotherapy but failed in clinical trials due to low/toxic effects. Recently, a dual modulation of transporters and natural derivatives have been examined to surmount this limitation. We examined breast cancer resistance protein (BCRP) inhibition in vitro and in vivo by P-gp inhibitors derived from natural compounds in previous studies. P-gp inhibitors increased the accumulation of the anticancer drug, topotecan (TPT)-a substrate of P-gp and BCRP, albeit with higher affinity for BCRP-in BCRP-overexpressing cells, resulting in cell death. These dual inhibitors, when orally co-administered with TPT, enhanced TPT bioavailability with slightly reduced total oral clearance (Clt/F) in rats. In xenograft mice, they strengthened oral TPT-induced tumor reduction with no alterations in body weight. Moreover, we investigated the effects of an oral drug formulation (Cremophor® EL, Tween® 80, and polyethylene glycol 400) on the transporters function. The excipients increased TPT accumulation in P-gp- or BCRP-overexpressing cells. Oral TPT bioavailability was higher with the formulation than with a control, as shown by the increases in the maximum plasma concentration (Cmax) and the area under the plasma concentration-time curve from zero to infinity (AUCINF) (p< 0.01). Therefore, oral TPT bioavailability was enhanced by P-gp/BCRP dual inhibition, which resulted in a formulation-mediated increase in absorption and decrease in elimination, and a dual inhibitor-mediated decrease in elimination. These results suggest that the combination of dual inhibition by a natural derivative and the drug formulation can be a useful clinical approach.

Drug-Like Small Molecule HSP27 Functional Inhibitor Sensitizes Lung Cancer Cells to Gefitinib or Cisplatin by Inducing Altered Cross-Linked Hsp27 Dimers.

Relationships between heat shock protein 27 (HSP27) and cancer aggressiveness, metastasis, drug resistance, and poor patient outcomes in various cancer types including non-small cell lung cancer (NSCLC) were reported, and inhibition of HSP27 expression is suggested to be a possible strategy for cancer therapy. Unlike HSP90 or HSP70, HSP27 does not have an ATP-binding pocket, and no effective HSP27 inhibitors have been identified. Previously, NSCLC cancer cells were sensitized to radiation and chemotherapy when co-treated with small molecule HSP27 functional inhibitors such as zerumbone (ZER), SW15, and J2 that can induce abnormal cross-linked HSP27 dimer. In this study, cancer inhibition effects of NA49, a chromenone compound with better solubility, longer circulation time, and less toxicity than J2, were examined in combination with anticancer drugs such as cisplatin and gefitinib in NSCLC cell lines. When the cytotoxic drug cisplatin was treated in combination with NA49 in epidermal growth factor receptors (EGFRs) WT cell lines, sensitization was induced in an HSP27 expression-dependent manner. With gefitinib treatment, NA49 showed increased combination effects in both EGFR WT and Mut cell lines, also with HSP27 expression-dependent patterns. Moreover, NA49 induced sensitization in EGFR Mut cells with a secondary mutation of T790M when combined with gefitinib. Augmented tumor growth inhibition was shown with the combination of cisplatin or gefitinib and NA49 in nude mouse xenograft models. These results suggest the combination of HSP27 inhibitor NA49 and anticancer agents as a candidate for overcoming HSP27-mediated drug resistance in NSCLC patients.

Quantification of Teicoplanin Using the HPLC-UV Method for Clinical Applications in Critically Ill Patients in Korea.

A high-performance liquid chromatography-ultraviolet detector (HPLC-UV) method has been used to quantify teicoplanin concentrations in human plasma. However, the limited analytical accuracy of previously bioanalytical methods for teicoplanin has given rise to uncertainty due to the use of an external standard. In this study, an internal standard (IS), polymyxin B, was applied to devise a precise, accurate, and feasible HPLC-UV method. The deproteinized plasma sample containing teicoplanin and an IS of acetonitrile was chromatographed on a C18 column with an acidic mobile phase consisting of NaH2PO4 buffer and acetonitrile (78:22, v/v) by isocratic elution and detection at 220 nm. The linearity was in the range 7.8-500 mg/L calculated by the ratio of the teicoplanin signal to the IS signal. This analytical method, validated by FDA guidelines with ICH Q2 (R1), was successfully applied to analyze the plasma samples of patients in the intensive care unit for treating serious resistant bacterial infectious diseases, such as those by methicillin-resistant Staphylococcus aureus and Enterococcus faecalis. The methods suggested the potential for use in routine clinical practice for therapeutic drug monitoring of teicoplanin, providing both improved accuracy and a wide range of linearity from lower than steady-state trough concentrations (10 mg/L) to much higher concentrations.

Optimization, validation, and comparison of a rapid method for the quantification of insulin-like growth factor 1 in serum using liquid chromatography-high-resolution mass spectrometry.

Human insulin-like growth factor 1 (IGF-I) is the primary mediator of the effects of the growth hormone (GH). Therefore, it has been used as a biomarker to detect the abuse of GH in sports. The measurement of IGF-I relies on mass-based and immunological approaches to analysis. Among the mass-based analysis methods, liquid chromatography-mass spectrometry (LC-MS) has a number of functional advantages. LC-MS measurements based on the quantification of IGF-I, according to trypsin digestion, are used in the most common method of analyzing doping. However, this method is time-consuming and subject to experimental variability. In this study, we optimized a rapid method for detecting IGF-I without the trypsin digestion step. This method of analysis uses an ultra-centrifugal filter and an LC-HRMS through narrow-range mass scan method. To verify the validity of this method, eight categories of validation testing were applied with the following results: linearity, R2 > 0.99; limit of detection, 15 ng/ml; limit of quantification, 20 ng/ml; accuracy, >99%; recovery rate, >95%; carryover, <0.03; and inter- and intra-day precision values, %CV < 2% and %CV < 6%, respectively. Furthermore, we discussed the correlation of the quantified concentration from two other methods, immunoradiometric assay (IRMA) and parallel reaction monitoring method, using 209 serum samples. In conclusion, although both mass spectrometry-based methods worked equally well in terms of analytical performance and correlation with IRMA results, narrow-range mass scan method had several advantages, such as time and cost savings and reliable reproducibility, over the existing methods.