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1.
Biomed Chromatogr ; : e5924, 2024 Jun 23.
Article in English | MEDLINE | ID: mdl-38922973

ABSTRACT

The co-administration of dapagliflozin (DPF) and sacubitril/valsartan (LCZ696) has emerged as a promising therapeutic approach for managing heart failure. Given that DPF and LCZ696 are substrates for P-glycoprotein, there is a plausible potential for drug-drug interactions when administered concomitantly. To investigate the pharmacokinetic changes when these drugs are co-administered, we have established and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method capable of simultaneously detecting DPF, LBQ657 (the active metabolite of sacubitril) and valsartan in rat plasma. This method has demonstrated selectivity, sensitivity, and accuracy. Drug-drug interactions were examined by the LC-MS/MS method. The mechanisms were investigated using everted intestinal sac models and Caco-2 cells. The results showed that DPF significantly increased the area under the curve (AUC(0-t)) (3,563.3 ± 651.7 vs. 7,146.5 ± 1,714.9 h µg/L) of LBQ657 (the active metabolite of sacubitril) and the AUC(0-t) (24,022.4 ± 6,774.3 vs. 55,728.3 ± 32,446.3 h µg/L) of valsartan after oral co-administration. Dapagliflozin significantly increased the amount of LBQ657 and valsartan in intestinal sacs by 1- and 1.25-fold at 2.25 h. Caco-2 cell uptake studies confirmed that P-glycoprotein is the transporter involved in this interaction. This finding enhances the understanding of drug-drug interactions in the treatment of heart failure and provides a guidence for clinical therapy.

2.
Inquiry ; 60: 469580231183695, 2023.
Article in English | MEDLINE | ID: mdl-37357728

ABSTRACT

As online health communities (OHCs) continue to proliferate, narrative reviews on doctors have become a vital reference source for patients when choosing online health services. However, the potential value of subjective information reflecting patient experiences in OHCs has not been fully explored. The present study seeks to investigate the impact of narrative reviews on patients' selection of e-doctors and the extent to which such reviews are moderated by doctors' specialties. This paper collected data from 747 doctors and 105 032 reviews from WeDoctor, one of China's most popular OHCs, in 2019. We employed Latent Dirichlet Allocation topic modeling to extract 3 topics and analyzed their effects on patient e-doctor choice using a multiple regression method. Our findings indicate that Topic 1, clinical skills and effects, had a positive impact on patient choice in OHCs (ß1 = .243, P < .001), as did Topic 2, service attitude and trust (ß2 = .130, P < .05). However, the impact of Topic 3, convenience, did not show a significant effect in this study. Moreover, our results suggest that the specialty of Internal Medicine can positively moderate the relationship between Topic 1 (clinical skills and effects) and patient e-doctor choice (ß9 = .087, P < .05). Based on the findings of this study, e-doctors are encouraged to enhance their technical competence to improve treatment effectiveness and adjust their communication methods to increase patient trust and sense of security. OHC platform managers should accurately understand the key factors that influence patient choice and take measures to improve their service quality accordingly.


Subject(s)
Medicine , Physicians , Telemedicine , Humans , Clinical Competence , Physician-Patient Relations , Surveys and Questionnaires , Quality of Health Care , Choice Behavior , Patient Participation
3.
Infect Drug Resist ; 16: 2611-2623, 2023.
Article in English | MEDLINE | ID: mdl-37152403

ABSTRACT

Purpose: Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a serious medical condition with a high short-term mortality rate, making accurate prognostic assessment essential for informed clinical decision-making. In this study, we aimed to develop a simple and effective prognostic model for predicting short-term mortality in patients with HBV-ACLF. Patients and Methods: To achieve our objective, we enrolled both a cross-sectional cohort (n = 291) and a retrospective cohort (n = 185) in this study. We collected laboratory and clinical data from these cohorts and performed univariate and multivariate logistic regression analyses to identify independent predictors of short-term mortality. Subsequently, we developed a novel prognostic score for HBV-ACLF, which was validated and assessed using receiver operating characteristic (ROC) curve analysis to determine its performance. Results: Our analysis revealed that the admission prealbumin (PAB) level was a robust independent predictor of 30-day mortality, with an area under the receiver operating characteristic (AUROC) of 0.760. Moreover, we developed the HIAPP score, a prognostic-score model based on PAB. The HIAPP score was significantly lower in survivors compared to non-survivors (-2.80±0.21 vs 0.97±0.41, P < 0.001). The HIAPP score's AUROC value was 0.899, which was found to be superior to the MELD score (AUROC = 0.795) and the CLIF-C ACLF score (AUC =0.781) and comparable to the COSSH-ACLF II score (AUC =0.825) for predicting 30-day mortality. These findings were also validated in a separate cohort, further supporting the utility of the HIAPP score as a prognostic tool for HBV-ACLF patients. Conclusion: Our study identifies the admission PAB level as a simple and valuable predictive index for 30-day mortality in HBV-ACLF patients. Furthermore, the HIAPP score, which incorporates PAB, PLT, INR, HE, and age, is an easy-to-use and pragmatic prognostic score in predicting short-term mortality.

4.
Front Pharmacol ; 13: 943812, 2022.
Article in English | MEDLINE | ID: mdl-36188594

ABSTRACT

Purpose: The "radiotherapy-pharmacokinetic" ("RT-PK") phenomenon refers to the fact that radiation can significantly alter the pharmacokinetic behavior of a drug. At present, it is not clear whether there is an "RT-PK" phenomenon that can affect apatinib during concurrent chemoradiotherapy. In this study, we used a rat irradiation model to study the effects of X-ray radiation on absorption, tissue distribution, and excretion of apatinib. Method: Healthy Sprague-Dawley (SD) rats were randomly divided into control and radiation groups. The radiation group was given an appropriate dose of abdominal X-ray radiation, while the control group was not given irradiation. After 24 h of recovery, both groups were given apatinib solution 45 mg/kg by gavage. A quantitative LC-MS/MS method was developed to determine the concentration of apatinib in the rats, so as to compare the differences between the control and radiation groups and thus investigate the modulating effect of radiation on the pharmacokinetics of apatinib in rats. Results: After abdominal X-ray irradiation, the area under the curve (AUC0-t) of apatinib in rat plasma decreased by 33.8% and 76.3% at 0.5 and 2 Gy, respectively. Clearance (CL) and volume of distribution (Vd) increased and were positively correlated with radiation dose. X-ray radiation significantly reduced the concentration of apatinib in the liver and small intestine, and there was no tissue accumulation. In excretion studies, we found that X-ray radiation reduced the cumulative excretion of apatinib in feces and urine by 11.24% and 86.17%, respectively. Conclusion: Abdominal X-ray radiation decreased plasma exposure, tissue distribution, and excretion of apatinib in rats, suggesting that the RT-PK phenomenon affects apatinib. We speculate that this RT-PK phenomenon is closely related to changes in metabolic enzymes in vivo. In clinical practice, when apatinib is combined with radiotherapy, attention should be paid to adjusting the dose of apatinib and optimizing the treatment plan to alleviate the adverse effects of this RT-PK phenomenon.

5.
J Infect Dev Ctries ; 16(8): 1336-1342, 2022 08 30.
Article in English | MEDLINE | ID: mdl-36099378

ABSTRACT

INTRODUCTION: The introduction of antiviral therapy in chronic hepatitis B (CHB) infection depends on precise evaluation of hepatic lesions. Total serum bile acids (TSBAs) are highly sensitive in monitoring liver dysfunction. We evaluated the predictive role of TSBAs for hepatic lesions in CHB patients with borderline alanine aminotransferase (ALT) and high level of hepatitis B virus (HBV) DNA copies. METHODOLOGY: 328 CHB patients were enrolled, 241 were hepatitis B e antigen (HBeAg)-positive and 87 were HBeAg-negative. Patients were further divided into two entities according to inflammation/fibrosis evaluated by liver biopsy, low-grade (inflammation grade < 2 and fibrosis stage < 2) and high-grade (inflammation grade ≥ 2 or/and fibrosis stage ≥ 2) cohorts. TSBAs were compared with noninvasive tools including aspartate aminnotransferase (AST)-to-platelet ratio index (APRI), fibrosis-4 (FIB-4) and red cell distribution width (RDW)-to-platelet ratio (RPR) to predict high-grade hepatic lesions in CHB subgroups. RESULTS: TSBAs, APRI, FIB-4 and RPR were statistically different between low- and high-grade patients in HBeAg-positive cohort. Only TSBAs showed significant difference between low and high grade in HBeAg-negative patients. Similarly, APRI, FIB-4 and RPR were correlated with different division of inflammation/fibrosis only in HBeAg-positive while TSBAs were correlated with inflammation/fibrosis levels in both HBeAg-positive and HBeAg-negative groups. Of the four indicators, the receiver operating characteristic (ROC) curve analysis showed that TSBAs have the maximum AUC (area under the curve) in HBeAg-negative group but the minimum in HBeAg-positive cohort. CONCLUSIONS: TSBAs can be used for predicting antiviral therapy in CHB patients with HBeAg-negative, borderline ALT and high HBV DNA.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Antiviral Agents/therapeutic use , Bile Acids and Salts , DNA, Viral , Fibrosis , Hepatitis B e Antigens , Hepatitis B, Chronic/drug therapy , Humans , Inflammation , Liver Cirrhosis/pathology
6.
Cytotherapy ; 23(10): 874-885, 2021 10.
Article in English | MEDLINE | ID: mdl-34116946

ABSTRACT

BACKGROUND AIMS: Cell-based regenerative medicine is an innovative field that can potentially alter the overall survival and quality of life of patients with devastating diseases. Several cell therapy products (CTPs) have been approved within the last two decades, and more are under development. The establishment of an effective developmental strategy in accordance with the regulatory bodies of each country/region is crucial for fast delivery of each respective CTP. In particular, facilitating investigational new drug (IND) approval is important for accelerating the transition from non-clinical to clinical research/trial phases. METHODS: Here the authors compared the non-clinical prerequisites for initiating clinical studies in five Asian countries/regions (India, China, Korea, Taiwan and Japan) from an industry viewpoint. The authors first identified the differences and tried to clarify the perspectives/considerations underpinning the different requirements. RESULTS: The authors' findings revealed that differences in regulations and development experiences, especially with CTPs, have led to clear differences in the non-clinical study package and its corresponding study design. CONCLUSIONS: By sharing experiences of the research and development of CTPs among Asian countries/regions and including not only industry but also regulatory authorities, we will be able to expedite cross-border IND approval and eventually contribute to the early delivery of innovative CTPs to many Asian patients.


Subject(s)
Cell- and Tissue-Based Therapy , Quality of Life , Asia , China , Humans , Japan
8.
Medicine (Baltimore) ; 99(23): e20548, 2020 Jun 05.
Article in English | MEDLINE | ID: mdl-32502018

ABSTRACT

Few studies have paid attention to the performances of non-invasive models in diagnosing stages of liver fibrosis and inflammation, which are critical for early and accurate assessment of prognostication and decisions on antiviral treatment in chronic hepatitis B infection patients with high hepatitis B virus DNA and normal or mildly elevated alanine transaminase levels (≤2 times upper limit of normal (ULN)). This study aimed to investigate the value of routine serum markers in evaluation of liver inflammation and fibrosis in these patients.A total of 370 consecutive chronic hepatitis B virus-infected patients who underwent liver biopsy were retrospectively analyzed. The Scheuer scoring system was adopted as the pathological standard for diagnosing liver inflammation and fibrosis. The receiver-operating characteristic curves (ROC) and the area under the ROC curves (AUROCs) were used to analyze the performances of the models, including aspartate transaminase to platelet ratio index (APRI), fibrosis index based on the 4 factors (FIB-4), red cell volume distribution width-to-platelet ratio (RPR), globulin-platelet model (GP), and gamma-glutamyl transpeptidase to platelet ratio index (GPR).To predict significant inflammation (G ≥2), the AUROC of APRI was higher than that of FIB-4 (0.705 vs 0.629, P = .001), RPR (0.705 vs 0.593, P < .001) and GP (0.705 vs 0.620, P = .002), equivalent to that of GPR (0.705 vs 0.690, P = .606). As for severe inflammation (≥G3) and significant fibrosis (≥S2), there was no statistic difference among them. To predict severe fibrosis (≥ S3), the AUROC of FIB-4 was higher than that of RPR (0.805 vs 0.750, P = .006) and GP (0.805 vs 0.755, P = .046), comparable to that of APRI (0.805 vs 0.785, P = .550) and GPR (0.805 vs 0.818, P = .694). As for significant liver histological changes (G ≥ 2 or/and S ≥ 2), the performance of APRI was higher than that of RPR (0.717 vs 0.652, P = .006), GP (0.717 vs 0.659, p = .011), equivalent to that of FIB-4 (0.717 vs 0.692, P = .254) and GPR (0.717 vs 0.680, P = .166).We found that APRI, GPR, and FIB-4 were more effective than RPR and GP for diagnosing liver inflammation and fibrosis.


Subject(s)
Alanine Transaminase/blood , Hepatitis B, Chronic/complications , Inflammation/diagnosis , Liver Cirrhosis/diagnosis , Adult , DNA, Viral , Erythrocyte Volume , Female , Globulins/analysis , Hepatitis B virus/genetics , Humans , Male , Platelet Count , Retrospective Studies , Severity of Illness Index , gamma-Glutamyltransferase/blood
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 640-7, 2016 Mar.
Article in Chinese | MEDLINE | ID: mdl-27400497

ABSTRACT

To satisfy the demand of multilayer films on polarization detection, polarized bidirectional reflectance distribution function of multilayer films on slightly rough substrate is established on the basis of first-order vector perturbation theory and polarization transfer matrix. Due to the function, light scattering polarization properties are studied under multi-factor impacts of two typical targets-monolayer anti-reflection film and multilayer high-reflection films. The result shows that for monolayer anti-reflection film, observing positions have a great influence on the degree of polarization, for the left of the peak increased and right decreased compared with the substrate target. Film target and bare substrate can be distinguished by the degree of polarization in different observation angles. For multilayer high-reflection films, the degree of polarization is significantly associated with the number and optical thickness of layers at different wavelengths of incident light and scattering angles. With the increase of the layer number, the degree of polarization near the mirror reflection area decreases. It reveals that the calculated results coincide with the experimental data, which validates the correctness and rationality of the model. This paper provides a theoretical method for polarization detection of multilayer films target and reflection stealth technology.

10.
Opt Express ; 24(9): 9397-411, 2016 May 02.
Article in English | MEDLINE | ID: mdl-27137556

ABSTRACT

A novel Monte Carlo model is proposed to acquire the reflective polarization information from a rough surface with arbitrary layers and profiles. Based on the micro-facets theory, the local normal vectors can be randomly sampled from the normal vector distribution of each layer. The incident light that propagates inside of the multi-layer media will be traced until being collected after leaving the surface or be ignored due to lacking enough energy. The simulated results (by our proposed theoretical model) agree well with the reported measured data and the analytical models from SCATMECH, which demonstrates the correctness and effectiveness of our model. Based on our model, the effects of the surface layer number, the surface geometry, the incident wavelength and polarization states of incidence on the reflective polarization from multi-layer surfaces have been analyzed in detail, which can be a guide in tasks such as target detection and so on.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 700-5, 2015 Mar.
Article in Chinese | MEDLINE | ID: mdl-26117882

ABSTRACT

Study on polarized skylight spectral characters while observation geometry changing in different solar zenith angles (SZA), viewing zenith angles (VZA) or relative azimuth angles (RAA). Simulation calculation of cloudless daylight polarimetric spectrum is realized based on the solver, vector discrete ordinate method, of radiative transfer equation. In the Sun's principal and perpendicular plane, the spectral irradiance data, varying at wavelengths in the range between 0.4 and 3 µm, are calculated to extend the atmospheric polarization spectral information under the conditions: the MODTRAN solar reference spectrur is the only illuminant source; the main influencing factors of polarized radiative transfer include underlying surface albedo, aerosol layers and components, and the absorption of trace gases. Simulation analysis results: (1) While the relative azimuth angle is zero, the magnitude of spectrum U/I is lower than 10(-7) and V/I is negligible, the degree of polarization and the spectrum Q/I are shaped like the letter V or mirror-writing U. (2) In twilight, when the Sun is not in FOV of the detector, the polarization of the daytime sky has two maximum near 0.51 and 2.75 µm, and a minimum near 1.5 µm. For arbitrary observation geometry, the spectral signal of V/I may be ignored. According to observation geometry, choosing different spectral bands or polarized signal will be propitious to targets detection.

12.
Int J Clin Exp Pathol ; 7(9): 6395-8, 2014.
Article in English | MEDLINE | ID: mdl-25337298

ABSTRACT

Mixed adenoneuroendocrine carcinoma (MANEC) is exceedingly rare with a poor outcome. In this article, we reported a MANEC in a 68-year-old woman with a symptom of abdominal pain and distension. MANEC derived from the ascending colon with highly aggressive behavior. The diagnosis and distinguish of MANEC must base on histological findings and immunohistochemical findings. In this case, microscopic observation showed tumor cells were arranged in conglobate and nested by fibrous tissue with a visible cell atypia and mitotic. NEC-like and exocrine glandular cells were also been seen in a single neoplasm. MANEC tissues were immunopositive for CK, CK20, P53, CK7, CDX-2, Ki-67 (70%+), E-cad, CD56, CEA, Syn, villin and CgA, and immunonegative for CA125, NSE, ER and PR. Here, the patient was treated by surgical operation and was followed-up near 3 months, no local recurrence and distant metastasis.


Subject(s)
Adenocarcinoma/pathology , Carcinoma, Neuroendocrine/pathology , Colonic Neoplasms/pathology , Intestinal Mucosa/pathology , Neoplasms, Complex and Mixed/pathology , Adenocarcinoma/chemistry , Adenocarcinoma/surgery , Aged , Biomarkers, Tumor/analysis , Biopsy , Carcinoma, Neuroendocrine/chemistry , Carcinoma, Neuroendocrine/surgery , Colectomy , Colonic Neoplasms/chemistry , Colonic Neoplasms/surgery , Female , Humans , Immunohistochemistry , Intestinal Mucosa/chemistry , Neoplasm Invasiveness , Neoplasms, Complex and Mixed/chemistry , Neoplasms, Complex and Mixed/surgery , Treatment Outcome
13.
Int J Clin Exp Med ; 7(8): 2377-9, 2014.
Article in English | MEDLINE | ID: mdl-25232441

ABSTRACT

In this article, we described a mucoepidermoid carcinoma (MEC) located in the left forearm of a 39-year-old pregnant woman. Here, the patient had a superficial tip size apophysis nearly 3 years, which begin to sustained growth after pregnant in 2012, and stopped growth after childbirth. MEC is a rare malignant tumor. Previously reports showed it mainly arise from the salivary, bronchial, thyroid, breast, lacrimal gland and conjunctiva. Here, we reported a case of MEC arising from the forearm gland for the first time. Histological finding showed a cystic and solid tumor in fibrous tissue below the squamous epithelium, and some columnar or cuboidal mucous cells covering on the epidermal cells or mixed with epidermal cells included in the tumor tissues. Also, Focal hyperplasia epidermal cells with round or oval nucleus in center were distributed in small pieces but no keratosis. The tumor tissues were immunopositive for CEA, P63, ki-67 (10%), CK7 and CK5/6, and immunonegative for CK20 and GCDFP-15. This case is a low-grade MEC and the patient's postoperative recovery is smooth.

14.
Int J Clin Exp Pathol ; 7(7): 4516-8, 2014.
Article in English | MEDLINE | ID: mdl-25120845

ABSTRACT

ACC derived from nasopharyngeal epithelial cells is rare, usually benign. In this article, we reported a nasopharyngeal adenoid cystic carcinoma (NACC) in a 31-year-old woman with a symptom of hoarseness, headache, epistaxis slightly, diplopia, facial numbness and dysphagia near 3 months. A tumor on the right side of the nasopharynx was confirmed by laryngoscope check and MRI of the skull base. Histopathological findings showed that tumor cells were arranged in cord-like or acinar-like by atypical hyperplastic epithelial cells forming a cribriform and tubular pattern, and immunohistochemical findings showed that tumor tissues were immunopositive for p63 (+), CK7 (+), CK19 (+), CK8 (+), CK18 (+), SMA (+), CK (+), p53 (++), S-100 (+) and Ki-67 (5%+), and negative for CD34 (-), CK5/6 (-), CEA (-) and CD117 (-). Patient was treated by surgical operation and radiotherapy, and was followed-up near 10 months, no local recurrence and distant metastasis.


Subject(s)
Carcinoma, Adenoid Cystic/pathology , Nasopharyngeal Neoplasms/pathology , Adult , Biomarkers, Tumor/analysis , Female , Humans , Immunohistochemistry
15.
Int J Clin Exp Pathol ; 7(5): 2654-7, 2014.
Article in English | MEDLINE | ID: mdl-24966981

ABSTRACT

In this article, we described a malignant myoepithelioma of the breast (MMB) in a 69-year-old woman. Breast cancer derived from myoepithelial cells is very rare, usually benign. The diagnosis of MMB based on histological and immunohistochemical finding. In this case, the author diagnosed the tumor as MMB, because tumor tissues were immunopositive for 34ßE12, P63, SMA, S-100, CD10, E-Cad and Ki-67, and immunnegative for CK5/6, desmin, ER, PR and C-erbB-2, because tumor tissue showed invasive growth and local hemorrhage or necrosis, suggesting malignant, and also because there was a transition between the tumor cells and hyperplastic myoepithelium of non-tumorous ducts. The patient's postoperative recovery is smooth and regular following of patient is essential.


Subject(s)
Breast Neoplasms/pathology , Myoepithelioma/pathology , Aged , Biomarkers, Tumor/analysis , Biopsy , Breast Neoplasms/chemistry , Breast Neoplasms/surgery , Cell Proliferation , Female , Humans , Hyperplasia , Immunohistochemistry , Mastectomy, Radical , Myoepithelioma/chemistry , Myoepithelioma/surgery , Necrosis , Neoplasm Invasiveness
16.
Int J Clin Exp Pathol ; 7(1): 456-9, 2014.
Article in English | MEDLINE | ID: mdl-24427372

ABSTRACT

In this article, we described an ovarian sclerosing stromal tumor (SST) in a young woman with ectopic pregnancy. It is important to distinguish SST from fibroma, thecoma, and lipoid cell tumors clinically and histologically. Several unique histologic features including pseudolobulation, sclerosis and prominent vascularity are clearly reflected at histopathological findings. The SST cells were immunopositive for CD34, Desmin and SMA, and negative for factor VIII-related antigen, CD31, S-100, ER and PR. The patient's postoperative recovery was smooth and she was discharged after 21 days.


Subject(s)
Ovarian Neoplasms/pathology , Pregnancy Complications, Neoplastic/pathology , Pregnancy, Tubal , Sex Cord-Gonadal Stromal Tumors/pathology , Adult , Female , Humans , Pregnancy
17.
Biochem Biophys Res Commun ; 439(3): 351-6, 2013 Sep 27.
Article in English | MEDLINE | ID: mdl-24012675

ABSTRACT

Receptor tyrosine kinases (RTKs) regulate many cellular processes, and Sprouty2 (Spry2) is known as an important regulator of RTK signaling pathways. Therefore, it is worth investigating the properties of Spry2 in more detail. In this study, we found that Spry2 is able to self-assemble into oligomers with a high-affinity KD value of approximately 16nM, as determined through BIAcore surface plasmon resonance analysis. The three-dimensional (3D) structure of Spry2 was resolved using an electron microscopy (EM) single-particle reconstruction approach, which revealed that Spry2 is donut-shaped with two lip-cover domains. Furthermore, the method of energy dispersive spectrum obtained through EM was analyzed to determine the elements carried by Spry2, and the results demonstrated that Spry2 is a silicon- and iron-containing protein. The silicon may contribute to the electroconductivity of Spry2, and this property exhibits a concentration-dependent feature. This study provides the first report of a silicon- and iron-containing protein, and its 3D structure may allow us (1) to study the potential mechanism through the signal transduction is controlled by switching the electronic transfer on or off and (2) to develop a new type of conductor or even semiconductor using biological or half-biological hybrid materials in the future.


Subject(s)
Intracellular Signaling Peptides and Proteins/chemistry , Membrane Proteins/chemistry , Animals , Electric Conductivity , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Iron/analysis , Membrane Proteins/metabolism , Microscopy, Electron , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Silicon/analysis
18.
PLoS One ; 8(6): e65762, 2013.
Article in English | MEDLINE | ID: mdl-23840364

ABSTRACT

Advanced gastrointestinal stromal tumors (GIST), a KIT oncogene-driven tumor, on imatinib mesylate (IM) treatment may develop secondary KIT mutations to confer IM-resistant phenotype. Second-line sunitinib malate (SU) therapy is largely ineffective for IM-resistant GISTs with secondary exon 17 (activation-loop domain) mutations. We established an in vitro cell-based platform consisting of a series of COS-1 cells expressing KIT cDNA constructs encoding common primary±secondary mutations observed in GISTs, to compare the activity of several commercially available tyrosine kinase inhibitors on inhibiting the phosphorylation of mutant KIT proteins at their clinically achievable plasma steady-state concentration (Css). The inhibitory efficacies on KIT exon 11/17 mutants were further validated by growth inhibition assay on GIST48 cells, and underlying molecular-structure mechanisms were investigated by molecular modeling. Our results showed that SU more effectively inhibited mutant KIT with secondary exon 13 or 14 mutations than those with secondary exon 17 mutations, as clinically indicated. On contrary, at individual Css, nilotinib and sorafenib more profoundly inhibited the phosphorylation of KIT with secondary exon 17 mutations and the growth of GIST48 cells than IM, SU, and dasatinib. Molecular modeling analysis showed fragment deletion of exon 11 and point mutation on exon 17 would lead to a shift of KIT conformational equilibrium toward active form, for which nilotinib and sorafenib bound more stably than IM and SU. In current preclinical study, nilotinib and sorafenib are more active in IM-resistant GISTs with secondary exon 17 mutation than SU that deserve further clinical investigation.


Subject(s)
Antineoplastic Agents/pharmacology , Gastrointestinal Neoplasms/drug therapy , Gastrointestinal Stromal Tumors/drug therapy , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-kit/genetics , Amino Acid Motifs , Animals , Benzamides/pharmacology , COS Cells , Chlorocebus aethiops , Dasatinib , Drug Resistance, Neoplasm/genetics , Drug Screening Assays, Antitumor , Humans , Hydrogen Bonding , Imatinib Mesylate , Indoles/pharmacology , Molecular Docking Simulation , Mutation, Missense , Piperazines/pharmacology , Protein Binding , Proto-Oncogene Proteins c-kit/antagonists & inhibitors , Proto-Oncogene Proteins c-kit/chemistry , Pyrimidines/pharmacology , Pyrroles/pharmacology , Sunitinib , Thiazoles/pharmacology
19.
J Proteome Res ; 12(8): 3573-85, 2013 Aug 02.
Article in English | MEDLINE | ID: mdl-23782096

ABSTRACT

Malignant tumors are relatively resistant to treatment due to their heterogeneous nature, drug resistance, and tendency for metastasis. Recent studies suggest that a subpopulation of cancer cells is responsible for the malignant outcomes. These cells are considered as cancer stem cells (CSC). Although a number of molecules have been identified in different cancer cells as markers for cancer stem cells, no promising markers are currently available for hepatocellular carcinoma cells. In this study, two clones of Hep3B cell lines were functionally characterized as control or CSC-like cells, based on properties including spheroid formation, drug resistance, and tumor initiation. Furthermore, their protein expression profiles were investigated by isobaric tags for relative and absolute quantitation (iTRAQ), and a total of 1,127 proteins were identified and quantified from the combined fractions; 50 proteins exhibited at least 2-fold differences between these two clones. These 50 proteins were analyzed by GeneGo and were found to be associated with liver neoplasms, hepatocellular carcinoma (HCC), and liver diseases. They were also components of metabolic pathways, immune responses, and cytoskeleton remodeling. Among these proteins, the expressions of S100P, S100A14, and vimentin were verified in several HCC cell lines, and their expressions were correlated with tumorigenicity in HCC cell lines. The functional significance of vimentin and S100A14 were also investigated and verified.


Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Hepatocellular/genetics , Cell Transformation, Neoplastic/genetics , Liver Neoplasms/genetics , Neoplastic Stem Cells/metabolism , Proteome/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Drug Resistance, Neoplasm/genetics , Gene Expression , Gene Expression Profiling , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Mass Spectrometry , Molecular Sequence Annotation , Neoplastic Stem Cells/pathology , Proteome/metabolism , S100 Proteins/genetics , S100 Proteins/metabolism , Staining and Labeling/methods , Vimentin/genetics , Vimentin/metabolism
20.
Bioorg Med Chem Lett ; 20(20): 6129-32, 2010 Oct 15.
Article in English | MEDLINE | ID: mdl-20833039

ABSTRACT

A series of azulene-based derivatives were synthesized as potent inhibitors for receptor tyrosine kinases such as FMS-like tyrosine kinase 3 (FLT-3). Systematic side chain modification of prototype 1a was carried out through SAR studies. Analogue 22 was identified from this series and found to be one of the most potent FLT-3 inhibitors, with good pharmaceutical properties, superior efficacy, and tolerability in a tumor xenograft model.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/therapeutic use , Azulenes/chemistry , Azulenes/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Receptor Protein-Tyrosine Kinases/antagonists & inhibitors , Animals , Antineoplastic Agents/blood , Antineoplastic Agents/pharmacology , Azulenes/blood , Azulenes/pharmacology , Cell Line, Tumor , Cell Proliferation , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Rats , Receptor Protein-Tyrosine Kinases/metabolism , fms-Like Tyrosine Kinase 3/antagonists & inhibitors
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