Abstract 5-Fluorouracil (5-FU) is known as a first-line chemotherapeutic agent against colorectal cancer (CRC), but drug resistance occurs frequently and significantly limits its clinical success. Our previous study showed that the protocadherin 17 ( PCDH17 ) gene was frequently methylated and functioned as a tumor suppressor in CRC. However, the relationship between PCDH17 and 5-FU resistance in CRC remains unclear. Here, we revealed that PCDH17 was more highly expressed in 5-FU-sensitive CRC tissues than in 5-FU-resistant CRC tissues, and high expression of PCDH17 was correlated with high BECN1 expression. Moreover, this expression profile contributed to superior prognosis and increased survival in CRC patients. Restoring PCDH17 expression augmented the 5-FU sensitivity of CRC in vitro and in vivo by promoting apoptosis and autophagic cell death. Furthermore, autophagy played a dominant role in PCDH17 -induced cell death, as an autophagy inhibitor blocked cell death to a greater extent than the pancaspase inhibitor Z-VAD-FMK. PCDH17 inhibition by siRNA decreased the autophagy response and 5-FU sensitivity. Mechanistically, we showed that c-Jun NH2-terminal kinase (JNK) activation was a key determinant in PCDH17 -induced autophagy. The compound SP600125, an inhibitor of JNK, suppressed autophagy and 5-FU-induced cell death in PCDH17 -reexpressing CRC cells. Taken together, our findings suggest for the first time that PCDH17 increases the sensitivity of CRC to 5-FU treatment by inducing apoptosis and JNK-dependent autophagic cell death. PCDH17 may be a potential prognostic marker for predicting 5-FU sensitivity in CRC patients.
A recent ion mobility-mass spectrometry (IM-MS) study of the nonapeptide bradykinin (BK, amino acid sequence Arg(1)-Pro(2)-Pro(3)-Gly(4)-Phe(5)-Ser(6)-Pro(7)-Phe(8)-Arg(9)) found evidence for 10 populations of conformations that depend upon the solution composition [J. Am. Chem. Soc. 2011, 133, 13810]. Here, the role of the three proline residues (Pro(2), Pro(3), and Pro(7)) in establishing these conformations is investigated using a series of seven analogue peptides in which combinations of alanine residues are substituted for prolines. IM-MS distributions of the analogue peptides, when compared to the distribution for BK, indicate the multiple structures are associated with different combinations of cis and trans forms of the three proline residues. These data are used to assign the structures to different peptide populations that are observed under various solution conditions. The assignments also show the connectivity between structures when collisional activation is used to convert one state into another.
During bioanalytical assay development and validation, maintaining the stability of the parent drug and metabolites of interest is critical. While stability of the parent drug has been thoroughly investigated, the stability of unanalyzed metabolites is often overlooked. When an unstable metabolite is known or suspected to interfere with measurement of the parent drug or other metabolites of interest through back-conversion or other routes, additional tests with these unstable metabolites should be conducted. Here, the development and validation of two assays for quantification of rosuvastatin, one in human plasma and one in human urine, was reported. To this end, additional sets of quality control samples were added during assay validation to ensure the reliability of the assays. Acid treatment of samples is shown to be necessary for rosuvastatin quantification. In this regard, stability issues caused by the metabolite, rosuvastatin lactone, may have been overlooked if assay development and validation had only considered the parent drug, rosuvastatin. These assays represent a case study for how to develop and validate assays with unstable metabolites. Taken together, unstable metabolites should be included in all applicable stability tests.
Abstract Summary: A protection‐graft‐deprotection method was developed to prepare chitosan‐ g ‐polycaprolactone graft copolymers, during which the ring‐opening copolymerization of ε ‐caprolactone onto phthaloylchitosan (PHCS) happened without any additional catalysis. The intermediate PHCS was introduced primarily to protect the active amino group of chitosan. After controlled experiments, the phthalimido compound was proposed to be a novel kind of organic catalyst for the ring‐opening polymerization of caprolactone monomers, while the hydroxyl group acted as an initiator. Hence, in this graft system, PHCS was endowed with both self‐catalysis and self‐initiation at the same time, and the PCL side chains grew from the hydroxyl groups of the chitosan backbone. magnified image
Macroautophagy/autophagy is a conserved catabolic process through which cellular excessive or dysfunctional proteins and organelles are transported to the lysosome for terminal degradation and recycling. Over the past few years increasing evidence has suggested that autophagy is not only a simple metabolite recycling mechanism, but also plays a critical role in the removal of intracellular pathogens such as bacteria and viruses. When autophagy engulfs intracellular pathogens, the pathway is called 'xenophagy' because it leads to the elimination of foreign microbes. Recent studies support the idea that xenophagy can be modulated by bacterial infection. Meanwhile, convincing evidence indicates that xenophagy may be involved in malignant transformation and cancer therapy. Xenophagy can suppress tumorigenesis, particularly during the early stages of tumor initiation. However, in established tumors, xenophagy may also function as a prosurvival pathway in response to microenvironment stresses including bacterial infection. Therefore, bacterial infection-related xenophagy may have an effect on tumor initiation and cancer treatment. However, the role and machinery of bacterial infection-related xenophagy in cancer remain elusive. Here we will discuss recent developments in our understanding of xenophagic mechanisms targeting bacteria, and how they contribute to tumor initiation and anticancer therapy. A better understanding of the role of xenophagy in bacterial infection and cancer will hopefully provide insight into the design of novel and effective therapies for cancer prevention and treatment.
// Hongming Pan 1,2,* , Liuxi Chen 1,2,* , Yinghua Xu 1,2 , Weidong Han 1,2 , Fang Lou 1,2 , Weiqiang Fei 2 , Shuiping Liu 2 , Zhao Jing 2 and Xinbing Sui 1,2 1 Department of Medical Oncology, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou, China 2 Biomedical Research Center and Key Laboratory of Biotherapy of Zhejiang Province, Hangzhou, China * These authors have contributed equally to this work Correspondence to: Xinbing Sui, email: // Keywords : autophagy, immune, cancer immunotherapy Received : September 16, 2015 Accepted : January 06, 2016 Published : January 13, 2016 Abstract Autophagy is an evolutionarily conserved catabolic process by which cellular components are sequestered into a double-membrane vesicle and delivered to the lysosome for terminal degradation and recycling. Accumulating evidence suggests that autophagy plays a critical role in cell survival, senescence and homeostasis, and its dysregulation is associated with a variety of diseases including cancer, cardiovascular disease, neurodegeneration. Recent studies show that autophagy is also an important regulator of cell immune response. However, the mechanism by which autophagy regulates tumor immune responses remains elusive. In this review, we will describe the role of autophagy in immune regulation and summarize the possible molecular mechanisms that are currently well documented in the ability of autophagy to control cell immune response. In addition, the scientific and clinical hurdles regarding the potential role of autophagy in cancer immunotherapy will be discussed.
Low-volume sampling devices offer the promise of lower discomfort and greater convenience for patients, potentially reducing patient burden and enabling decentralized clinical trials. In this study, we determined whether low-volume sampling devices produce pharmacokinetic (PK) data comparable to conventional venipuncture for a diverse set of monoclonal antibodies (mAbs) and small molecules. We adopted an open-label, non-randomized, parallel-group, single-site study design, with four cohorts of 10 healthy subjects per arm. The study drugs, doses, and routes of administration included: crenezumab (15 mg/kg, intravenous infusion), etrolizumab (210 mg, subcutaneous), GDC-X (oral), and hydroxychloroquine (HCQ, 200 mg, oral). Samples were collected after administration of a single dose of each drug using conventional venipuncture and three low-volume capillary devices: TassoOne Plus for liquid blood, Tasso-M20 for dry blood, both applied to the arm, and Neoteryx Mitra® for dry blood obtained from fingertips. Serum/plasma concentrations from venipuncture and TassoOne Plus samples overlapped and PK parameters were comparable for all drugs, except HCQ. After applying a baseline hematocrit value, the dry blood concentrations and PK parameters for the two monoclonal antibodies were comparable to those obtained from venipuncture. For the two small molecules, two bridging strategies were evaluated for converting dry blood concentrations to equivalent plasma concentrations. A baseline hematocrit correction and/or linear regression-based correction was effective for GDC-X, but not for HCQ. Additionally, the study evaluated the bioanalytical data quality and comparability from the various collection methods, as well as patient preference for the devices.
The urose of this study was to observe the dynamic changes of liver damage in mice infected with Schistosoma jaonicum(S.jaonicum) and investigate the correlation among granulomatous lesions,liver fibrosis and serological indexes.Mice were infected subcutaneously with cercariae of S.jaonicum,and then sacrificed to observe the athological changes of livers and record the liver index regularly.Liver samles were embedded in araffin for routine histological examination.The sizes of egg granuloma and degrees of liver fibrosis were observed dynamically by HE stain and Masson's trichrome stain,resectively.The liver-associated AST and ALT levels in individual serum samles were measured in enzymatic assay using a commercial kit.The content of hyaluronic acid(HA),laminin(LN) and Ⅳ collagen(Ⅳ-C) in serum were detected by radioimmunoassay.It was found that bleeding oints began to emerge on 24d.i.and yellowish-white dots began to emerge on 29d.i.on the surface of livers.HE stain showed that numerous small and mixed inflammatory cell foci aeared on 21d,and eggs without granulomatous reaction could be seen on 28d.Egg granuloma resented on 29d and the size of the granuloma reached maximum on 42d.i.The ALT/AST level in serum elevated obviously on 28d,eaked on 39d,began to decrease on 42d and was closed to normal level on 70d.i..There were ositive correlation between aminotransferase concentration and the size of liver granuloma of infected mice(0.01).Masson's stain demonstrated that liver fibrosis could be seen from 42d.i.and increased gradually.Meanwhile,the levels of serum HA and LN increased with the emergence of fibrosis.Ⅳ-C,however,showed no obvious change along with fibrosis aggravation.But there were no correlation between fibrosis arameters and Masson's stain.It is evident that liver granuloma and fibrosis are the rimary causes for liver damage.The serological aminotransferase changes are consistent with the rogress in liver athology.But serum fibrosis indexes could not reresent early liver fibrosis aroriately.
GDC-0334 is a novel small molecule inhibitor of transient receptor potential cation channel member A1 (TRPA1), a promising therapeutic target for many nervous system and respiratory diseases. The pharmacokinetic (PK) profile and pharmacodynamic (PD) effects of GDC-0334 were evaluated in this first-in-human (FIH) study. A starting single dose of 25 mg was selected based on integrated preclinical PK, PD, and toxicology data following oral administration of GDC-0334 in guinea pigs, rats, dogs, and monkeys. Human PK and PK-PD of GDC-0334 were characterized after single and multiple oral dosing using a population modeling approach. The ability of GDC-0334 to inhibit dermal blood flow (DBF) induced by topical administration of allyl isothiocyanate (AITC) was evaluated as a target-engagement biomarker. Quantitative models were developed iteratively to refine the parameter estimates of the dose-concentration-effect relationships through stepwise estimation and extrapolation. Human PK analyses revealed that bioavailability, absorption rate constant, and lag time increase when GDC-0334 was administered with food. The inhibitory effect of GDC-0334 on the AITC-induced DBF biomarker exhibited a clear sigmoid-Emax relationship with GDC-0334 plasma concentrations in humans. This study leveraged emerging preclinical and clinical data to enable iterative refinement of GDC-0334 mathematical models throughout the FIH study for dose selection in subsequent cohorts throughout the study. Study Highlights WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC? GDC-0334 is a novel, small molecule TRPA1 inhibitor and a pharmacokinetic-pharmacodynamic (PK-PD) modeling strategy could be implemented in a systematic and step-wise manner to build and learn from emerging data for early clinical development. WHAT QUESTION DID THIS STUDY ADDRESS? Can noncompartmental and population-based analyses be used to describe the PK and PD characteristics of GDC-0334 in preclinical and clinical studies? WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE? GDC-0334 exposure generally increased with dose in rats, dogs, and monkeys. The starting dose (25 mg) in the clinical study was determined based on the preclinical data. GDC-0334 exhibited linear PK in humans and the bioavailability was increased with food. The inhibitory effect of GDC-0334 on dermal blood flow induced by the TRPA1 agonist allyl isothiocyanate in humans indicates a clear PK-PD relationship. HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE? The models developed based on TRPA1 agonist-induced dermal blood flow inhibition data can be used to predict PK-PD relationships in future preclinical and clinical studies evaluating new drug entities that target TRPA1.
Abstract Background: In China, traditional Chinese medicine (TCM) is an increasingly important part of the treatment of non-small cell lung cancer (NSCLC), which usually includes a combination of prescription and syndrome differentiation. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have been proven to be the first-line drugs for the treatment of advanced EGFR mutation-positive NSCLC. In China, EGFR-TKIs are used in combination with traditional Chinese medicines to reduce side effects and/or enhance effectiveness. Nevertheless, the relationship between TCMs and EGFR-TKIs remain unclear. This meta-review aimed to explore the clinical evidence of TCMs combined with EGFR-TKIs in the treatment of NSCLC. Methods: Related studies were found by searching the databases of EMBASE, PubMed, Web of Science, MEDLINE, Cochrane library database, China Academic Journals (CNKI), Wanfang and Weipu. This study included 57 randomized controlled trials, all of these were processed by Stata software (version 12.0). In the study, all the materials are published articles, patient anonymity and informed consent and ethics Approval/Institutional review board are not necessary. Results: This study demonstrated that the objective response rate was higher in the group of TCMs plus EGFR-TKIs than in the group of EGFR-TKIs alone (risk ratios 1.39, 95% confidence intervals [1.29, 1.50]). Further research of specific herbal medicines showed that Huangqi, Baishu, Fuling, Gancao, Maidong, Baihuashecao, Shashen, Dangshen and Renshen, had significant higher contributions to results. Conclusion: TCMs may improve the efficacy of EGFR-TKIs in the treatment of NSCLC.
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