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1.
Med Phys ; 47(10): 5235-5249, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32654194

ABSTRACT

PURPOSE: To develop an in vivo dosimeter system for stereotactic body radiation therapy (SBRT) that can perform accurate and precise real-time measurements, using a microsized amount of a photostimulable phosphor (PSP), BaFBr:Eu2+ . METHODS: The sensitive volume of the PSP was 1.26 × 10-5  cm3 . The dosimeter system was designed to apply photostimulation to the PSP after the decay of noise signals, in synchronization with the photon beam pulse of a linear accelerator (LINAC), to eliminate the noise signals completely using a time separation technique. The noise signals included stem signals, and radioluminescence signals generated by the PSP. In addition, the dosimeter system was built on a storage-type dosimeter that could read out a signal after an arbitrary preset number of photon beam pulses were incident. First, the noise and photostimulated luminescence (PSL) signal decay times were measured. Subsequently, we confirmed that the PSL signals could be exclusively read out within the photon beam pulse interval. Finally, using a water phantom, the basic characteristics of the dosimeter system were demonstrated under SBRT conditions, and the feasibility for clinical application was investigated. The reproducibility, dose linearity, dose-rate dependence, temperature dependence, and angular dependence were evaluated. The feasibility was confirmed by measurements at various dose gradients and using a representative treatment plan for a metastatic liver tumor. A clinical plan was created with a two-arc beam volumetric modulated arc therapy using a 10 MV flattening filter-free photon beam. For the water phantom measurements, the clinical plan was compiled into a plan with a fixed gantry angle of 0°. To evaluate the energy dependence during SBRT, the percent depth dose (PDD) was measured and compared with those calculated via Monte Carlo (MC) simulations. RESULTS: All the PSL signals could be read out while eliminating the noise signals within the minimum pulse interval of the LINAC. Stable real-time measurements could be performed with a time resolution of 56 ms (i.e., number of pulses = 20). The dose linearity was good in the dose range of 0.01-100 Gy. The measurements agreed within 1% at dose rates of 40-2400 cGy/min. The temperature and angular dependence were also acceptable since these dependencies had only a negligible effect on the measurements in SBRT. At a dose gradient of 2.21 Gy/mm, the measured dose agreed with that calculated using a treatment planning system (TPS) within the measurement uncertainties due to the probe position. For measurements using a representative treatment plan, the measured dose agreed with that calculated using the TPS within 0.5% at the center of the beam axis. The PDD measurements agreed with the MC calculations to within 1% for field sizes <5 × 5 cm2 . CONCLUSION: The in vivo dosimeter system developed using BaFBr:Eu2+ is capable of real-time, accurate, and precise measurement under SBRT conditions. The probe is smaller than a conventional dosimeter, has excellent spatial resolution, and can be valuable in SBRT with a steep dose distribution over a small field. The developed PSP dosimeter system appears to be suitable for in vivo SBRT dosimetry.


Subject(s)
In Vivo Dosimetry , Radiosurgery , Monte Carlo Method , Optical Fibers , Radiation Dosimeters , Radiometry , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted , Reproducibility of Results
2.
Biochem Biophys Rep ; 22: 100740, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32099910

ABSTRACT

Endometrial cancer is the most common gynecologic malignancy and is associated with increased morbidity each year, including young people. However, its mechanisms of proliferation and progression are not fully elucidated. It is well known that abnormal glycosylation is involved in oncogenesis, and fucosylation is one of the most important types of glycosylation. In particular, fucosyltransferase 8 (FUT8) is the only FUT responsible for α1, 6-linked fucosylation (core fucosylation), and it is involved in various physiological as well as pathophysiological processes, including cancer biology. Therefore, we aimed to identify the expression of FUT8 in endometrial endometrioid carcinoma and investigate the effect of the partial silencing of the FUT8 gene on the cell proliferation of Ishikawa cells, an epithelial-like endometrial cancer cell line. Quantitative real-time PCR analysis showed that FUT8 gene expression was significantly elevated in the endometrial endometrioid carcinoma, compared to the normal endometrium. The immunostaining of FUT8 and Ulex europaeus Agglutinin 1 (UEA-1), a kind of lectin family specifically binding to fucose, was detected endometrial endometrioid carcinoma. The proliferation assay showed FUT8 partial knockdown by transfection of siRNA significantly suppressed the proliferation of Ishikawa cells, concomitant with the upregulation in the gene expressions associated with the interesting pathways associated with de-ubiquitination, aspirin trigger, mesenchymal-epithelial transition (MET) et al. It was suggested that the core fucosylation brought about by FUT8 might be involved in the proliferation of endometrial endometrioid carcinoma cells.

3.
AAPS PharmSciTech ; 18(4): 1203-1212, 2017 May.
Article in English | MEDLINE | ID: mdl-27431914

ABSTRACT

Poorly water-soluble compounds have a potential risk of low and variable bioavailability caused by incomplete dissolution. Incorporation of organic acids as pH modifiers is effective method for solubility enhancement of basic compounds and requires no special technique and equipment. The purpose of this study was to evaluate the effect of manufacturing method on the extent of drug solubility enhancement. We successfully prepared the granules and tablets containing ketoconazole (KZ), which is weakly basic, as a model compound and citric acid as a pH modifier using conventional wet and dry granulations. KZ solubility under non-sink condition was enhanced with supersaturation using both wet and dry granulations. High-shear granulation was the most effective method in terms of KZ dissolution enhancement, because both an intimate contact and strong bonding between KZ and incorporated acid were achieved. KZ dissolved amount from the granules prepared by high-shear granulation was about eight times higher than that from the granules without the acid. The granulation involved to suppress a diffusion of acid dissolved, leading to the effectively maintained supersaturation state. The bioavailability of KZ after oral administration to rats was improved by applying high-shear granulation with citric acid independent of gastrointestinal pH. The granules prepared by high-shear granulation showed the bioavailability about 1.7-fold higher than that of the physical mixture in rats with and without neutralization of stomach. As a result, both the dissolution and absorption rates of KZ after oral administration were enhanced using conventional manufacturing technology.


Subject(s)
Ketoconazole/pharmacokinetics , Absorption, Physiological , Administration, Oral , Animals , Biological Availability , Chemistry, Pharmaceutical , Citric Acid/chemistry , Hydrogen-Ion Concentration , Ketoconazole/administration & dosage , Ketoconazole/chemistry , Rats , Solubility , Tablets/chemistry , Water/chemistry
4.
Masui ; 65(9): 976-981, 2016 09.
Article in Japanese | MEDLINE | ID: mdl-30358330

ABSTRACT

BACKGROUND: When antagonism is performed using sugammadex after continuous infusion of rocuronium, if the total amount of residual rocuronium can be esti- mated prior to performing antagonism, antagonism without excess or deficiency of sugammadex will be made possible. We therefore prepared a simple formula to predict residual amount of rocuronium in the body, which can be easily applied in clinical setting, and veri- fied it using Tivatrainer©. METHODS: 1. Pharmacokinetics of rocuronium was simulated, using a 3-compartment model. The following assumptions were made to derive the simple for- mula : when rocuronium is continuously infused to reach the steady state plasma concentration, an equal concentration in each compartment is reached. Only the amounts of rocuronium infused to the central com- partment and rocuronium excreted from there are thus considered, and these two amounts are in balance. For pharmacokinetic parameters, we referred to V. Saldien, Anesth Analg 2003 ; 97 : 44-9. 2. The prepared simple formula was verified using Tivatrainero. We considered a model in which initial boluses of 0.3, 0.6, 0.9, and 1.2 mg · kg(-1) were adminis- tered, and continuous infusion began at 30 minutes at the rate of 0.2, 0.3, 0.4, 0.5, 0.6, and 0.8 mg - kg-1 - hr-1. Patients with body weight of 50, 60, 70, and 80 kg were investigated. RESULTS: 1. The derived simple formula was as fol- lows : Q=0.74 X R Q Total residual amount of rocuronium (mg) R Dose per hour (mg · hr(-1)) 2. The predicted value of the total residual amount obtained from the simple formula was consistent with the value predicted by Tivatrainer© with a high preci- sion within the error of 1.4%. Convergence time until the stable state was reached varied depending on the condition. However, it took approximately 150 minutes after the beginning of continuous infusion.for the error between values predicted by the simple formula and Tivatrainer© to stabilize within 5 mg. CONCLUSIONS: We prepared a simple formula to esti- mate the total residual amount of rocuronium at a steady state. The value predicted by the simple for- mula agreed with the value predicted by Tivatrainer) with a high precision.


Subject(s)
Neuromuscular Nondepolarizing Agents/pharmacokinetics , Rocuronium/pharmacokinetics , Humans , Neuromuscular Blockade
5.
Eur J Pharm Sci ; 76: 225-30, 2015 Aug 30.
Article in English | MEDLINE | ID: mdl-25988287

ABSTRACT

Formulation development of poorly water-soluble compounds can be challenging because of incomplete dissolution that causes low and variable bioavailability. Enhancing compound solubility is important and many techniques have been investigated to that end, but they require specific materials and machinery. This study investigates the incorporation of a pH-modifier as a method to increase compound solubility and uses ketoconazole (KZ), which is weakly basic (pKa: 6.5), as a model compound. Organic acids are effective pH-modifiers and are generally used in pharmaceutical industries. We successfully obtained granules containing variable organic acids (KZ/acid granule) using a high-shear mixer. Dissolution tests of the KZ/acid granule resulted in highly enhanced solubility under non-sink conditions. Adding water-soluble acids, such as citric acid (CA) and tartaric acid, resulted in more than 8-fold higher dissolution at pH 6.0 compared to that of KZ only. The granules containing citric acid (KZ/CA granule) improved the dissolution of KZ after oral administration to rats under low gastric acid conditions, where the bioavailability of the KZ/CA granules at elevated gastric pH was comparable with that of KZ only at gastric acidic pH. The incorporation of organic acids would result in effective therapeutic outcomes independent of gastric pH in patients. In addition, higher bioavailability of KZ was observed after oral administration of KZ/CA granules under gastric acidic pH conditions than that of KZ alone. Thus, CA improved the dissolution and absorption rate of KZ after oral administration.


Subject(s)
Citric Acid/administration & dosage , Intestinal Absorption/drug effects , Ketoconazole/pharmacokinetics , Stomach/drug effects , Administration, Oral , Animals , Biological Availability , Chemistry, Pharmaceutical , Citric Acid/chemistry , Gastric Acid/metabolism , Gastric Mucosa/metabolism , Hydrogen-Ion Concentration , Ketoconazole/administration & dosage , Ketoconazole/blood , Ketoconazole/chemistry , Male , Proton Pump Inhibitors/pharmacology , Rats, Wistar , Solubility , Tartrates/chemistry , Technology, Pharmaceutical/methods
6.
J Biol Chem ; 287(18): 14456-66, 2012 Apr 27.
Article in English | MEDLINE | ID: mdl-22375007

ABSTRACT

The physiological role of multidrug resistance protein 4 (Mrp4, Abcc4) in the testes is unknown. We found that Mrp4 is expressed primarily in mouse and human Leydig cells; however, there is no current evidence that Mrp4 regulates testosterone production. We investigated its role in Leydig cells, where testosterone production is regulated by cAMP, an intracellular messenger formed when the luteinizing hormone (LH) receptor is activated. Because Mrp4 regulates cAMP, we compared testosterone levels in Mrp4(-/-) and Mrp4(+/+) mice. Young Mrp4(-/-) mice had significantly impaired gametogenesis, reduced testicular testosterone, and disruption of Leydig cell cAMP homeostasis. Both young and adult mice had impaired testosterone production. In Mrp4(-/-) primary Leydig cells treated with LH, intracellular cAMP production was impaired and cAMP-response element-binding protein (CREB) phosphorylation was strongly attenuated. Notably, expression of CREB target genes that regulate testosterone biosynthesis was reduced in Mrp4(-/-) Leydig cells in vivo. Therefore, Mrp4 is required for normal Leydig cell testosterone production. However, adult Mrp4(-/-) mice are fertile, with a normal circulating testosterone concentration. The difference is that in 3-week-old Mrp4(-/-) mice, disruption of gonadal testosterone production up-regulates hepatic Cyp2b10, a known testosterone-metabolizing enzyme. Therefore, defective testicular testosterone production de-regulates hepatic Cyp-mediated testosterone metabolism to disrupt gametogenesis. These findings have important implications for understanding the side effects of therapeutics that disrupt Mrp4 function and are reported to alter androgen production.


Subject(s)
Aryl Hydrocarbon Hydroxylases/biosynthesis , Leydig Cells/metabolism , Liver/enzymology , Multidrug Resistance-Associated Proteins/metabolism , Spermatogenesis/physiology , Steroid Hydroxylases/biosynthesis , Testosterone/biosynthesis , Animals , Aryl Hydrocarbon Hydroxylases/genetics , Cyclic AMP/genetics , Cyclic AMP/metabolism , Cyclic AMP Response Element-Binding Protein/genetics , Cyclic AMP Response Element-Binding Protein/metabolism , Cytochrome P450 Family 2 , Gene Expression Regulation, Enzymologic/physiology , Humans , Male , Mice , Mice, Knockout , Multidrug Resistance-Associated Proteins/genetics , Receptors, LH/genetics , Receptors, LH/metabolism , Steroid Hydroxylases/genetics , Testosterone/genetics , Up-Regulation/physiology
7.
Mod Pathol ; 23(4): 581-92, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20118911

ABSTRACT

The purpose of this study was to confirm that the grades of lymph vessel tumor emboli in biopsy specimens obtained before neoadjuvant therapy and in the surgical specimens obtained after neoadjuvant therapy according to the grading system we devised are significant histological outcome predictor for invasive ductal carcinoma (IDC) patients who received neoadjuvant therapy. The subjects of this study were the 318 consecutive IDC patients who had received neoadjuvant therapy in our institution. The lymph vessel tumor embolus grades in the biopsy specimens and in the surgical specimens were significantly associated with the increases in mean number of nodal metastases. Multivariate analyses with well-known prognostic factors and p53 expression in tumor-stromal fibroblasts clearly showed that the lymph vessel tumor embolus grade based on the biopsy specimens and based on the surgical specimens significantly increased the hazard rates for tumor recurrence and tumor-related death in all the IDC patients as a whole, in the IDC patients who did not have nodal metastasis, and in the IDC patients who had nodal metastasis, and the outcome-predictive power of the lymph vessel tumor embolus grades based on the surgical specimens was superior to that of the lymph vessel tumor embolus grades based on the biopsy specimens. The grades in the grading system for lymph vessel tumor emboli were significantly associated with nodal metastasis, and the histological grading system is an excellent system for accurately predicting the outcome of patients with IDC of the breast who have received neoadjuvant therapy.


Subject(s)
Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Lymphatic Metastasis/pathology , Neoplastic Cells, Circulating/pathology , Adult , Aged , Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/mortality , Carcinoma, Ductal, Breast/drug therapy , Carcinoma, Ductal, Breast/mortality , Disease-Free Survival , Female , Humans , Immunohistochemistry , Middle Aged , Neoadjuvant Therapy , Prognosis , Proportional Hazards Models
8.
Ann Surg Oncol ; 15(2): 547-54, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18043979

ABSTRACT

PURPOSE: Aurora-A, also known as STK15/BTAK, is a member of the protein serine/threonine kinase family, and experimental studies have revealed that Aurora-A plays critical roles in cell mitosis and in carcinogenesis. However, no clinical studies on Aurora-A expression in non-small-cell lung cancer (NSCLC) have been reported. Thus, the present study was conducted to assess the clinical significance of Aurora-A status. EXPERIMENTAL DESIGN: A total of 189 consecutive patients with resected pathologic (p-)stage I-IIIA, NSCLC were retrospectively reviewed, and immunohistochemical staining was used to detect Aurora-A expression. RESULTS: Aurora-A expression was negative in 31 patients (16.4%); among Aurora-A positive patients, 124 patients showed pure diffuse cytoplasmic Aurora-A expression and the other 34 patients showed perimembrane Aurora-A expression. Perimembrane Aurora-A tumors showed the highest proliferative index (PI) (mean PIs for negative, diffuse cytoplasmic, and perimembrane tumors: 49.2, 41.7, and 63.5, respectively; P < .001). Five-year survival rates of Aurora-A negative, diffuse cytoplasmic, and perimembrane patients were 67.8%, 66.7%, and 47.6%, respectively, showing the poorest postoperative survival in perimembrane patients (P = .033). Subset analyses revealed that perimembrane Aurora-A expression was a significant factor to predict a poor prognosis in squamous cell carcinoma patients, not in adenocarcinoma patients. A multivariate analysis confirmed that perimembrane Aurora-A expression was an independent and significant factor to predict a poor prognosis. CONCLUSIONS: Perimembrane Aurora-A status was a significant factor to predict a poor prognosis in correlation with enhanced proliferative activity in NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Lung Neoplasms/metabolism , Protein Serine-Threonine Kinases/metabolism , Adenocarcinoma/metabolism , Adenocarcinoma/mortality , Adenocarcinoma/physiopathology , Aged , Aurora Kinase A , Aurora Kinases , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/physiopathology , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/physiopathology , Cell Proliferation , Female , Humans , Immunohistochemistry , In Situ Nick-End Labeling , Lung Neoplasms/mortality , Lung Neoplasms/physiopathology , Male , Middle Aged , Multivariate Analysis , Prognosis , Proportional Hazards Models , Retrospective Studies , Survival Analysis
9.
Drug Metab Dispos ; 35(12): 2166-76, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17823233

ABSTRACT

Olmesartan, a novel angiotensin II AT1-receptor antagonist, is excreted into both bile and urine, with minimal metabolism. Because olmesartan is a hydrophilic anionic compound, some transporters could be involved in its hepatic and renal clearance. In this study, we characterized the role of human drug transporters in the pharmacokinetics of olmesartan and determined the contribution of each transporter to the overall clearance of olmesartan. Olmesartan was significantly taken up into human embryonic kidney 293 cells expressing organic anion-transporting polypeptide (OATP) 1B1, OATP1B3, organic anion transporter (OAT) 1, and OAT3. We also observed its saturable uptake into human hepatocytes and kidney slices. Estimated from the relative activity factor method and application of specific inhibitors, the relative contributions of OATP1B1 and OATP1B3 to the uptake of olmesartan in human hepatocytes were almost the same, whereas OAT3 was predominantly involved in its uptake in kidney slices. The vectorial transport of olmesartan was observed in OATP1B1/multidrug resistance-associated protein (MRP) 2 double transfectants, but not in OATP1B1/multidrug resistance (MDR) 1 and OATP1B1/breast cancer resistance protein (BCRP) transfectants. ATP-dependent transport into membrane vesicles expressing human MRP2 and MRP4 was clearly observed, with K(m) values of 14.9 and 26.2 microM, respectively, whereas the urinary excretion of olmesartan in Mrp4-knockout mice was not different from that of control mice. We also investigated the transcellular transport of olmesartan medoxomil, a prodrug of olmesartan. Vectorial basal-to-apical transport was observed in OATP1B1/MRP2, OATP1B1/MDR1 double, and OATP1B1/BCRP double transfectants, suggesting the possible involvement of MRP2, MDR1, and BCRP in the limit of intestinal absorption of olmesartan medoxomil. From these results, we suggest that multiple transporters make a significant contribution to the pharmacokinetics of olmesartan and its prodrug.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/metabolism , Imidazoles/metabolism , Kidney/metabolism , Liver/metabolism , Membrane Transport Proteins/metabolism , Prodrugs/metabolism , Tetrazoles/metabolism , ATP Binding Cassette Transporter, Subfamily B , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 2 , ATP-Binding Cassette Transporters/metabolism , Adenosine Triphosphate/metabolism , Angiotensin II Type 1 Receptor Blockers/pharmacokinetics , Animals , Cell Line , Dogs , Dose-Response Relationship, Drug , Estrone/analogs & derivatives , Estrone/metabolism , Female , Hepatocytes/drug effects , Hepatocytes/metabolism , Humans , Imidazoles/pharmacokinetics , In Vitro Techniques , Kinetics , Liver/drug effects , Liver-Specific Organic Anion Transporter 1 , Membrane Transport Proteins/drug effects , Membrane Transport Proteins/genetics , Mice , Mice, Knockout , Multidrug Resistance-Associated Protein 2 , Multidrug Resistance-Associated Proteins/deficiency , Multidrug Resistance-Associated Proteins/metabolism , Neoplasm Proteins/metabolism , Olmesartan Medoxomil , Organic Anion Transporters/metabolism , Organic Anion Transporters, Sodium-Independent/metabolism , Penicillin G/pharmacology , Probenecid/pharmacology , Prodrugs/pharmacokinetics , Protein Binding , Protein Isoforms/metabolism , Sincalide/metabolism , Solute Carrier Organic Anion Transporter Family Member 1B3 , Tetrazoles/pharmacokinetics , Transfection , p-Aminohippuric Acid/pharmacology
10.
Cancer Res ; 67(14): 6965-72, 2007 Jul 15.
Article in English | MEDLINE | ID: mdl-17638908

ABSTRACT

The use of probe substrates and combinations of ATP-binding cassette (ABC) transporter knockout (KO) animals may facilitate the identification of common substrates between apparently unrelated ABC transporters. An unexpectedly low concentration of the purine nucleotide analogue, 9-(2-(phosphonomethoxy)ethyl)-adenine (PMEA), and up-regulation of Abcg2 in some tissues of the Mrp4 KO mouse prompted us to evaluate the possibility that Abcg2 might transport purine-derived drugs. Abcg2 transported and conferred resistance to PMEA. Moreover, a specific Abcg2 inhibitor, fumitremorgin C, both increased PMEA accumulation and reversed Abcg2-mediated PMEA resistance. We developed Mrp4 and Abcg2 double KO mice and used both single KOs of Abcg2 and Mrp4 mice to assess the role of these transporters in vivo. Abcg2 contributed to PMEA accumulation in a variety of tissues, but in some tissues, this contribution was only revealed by the concurrent absence of Mrp4. Abcg2 also transported and conferred resistance to additional purine analogues, such as the antineoplastic, 2-chloro-2'-deoxyadenosine (cladribine) and puromycin, a protein synthesis inhibitor that is often used as a dominant selectable marker. Purine analogues interact with ABCG2 by a site distinct from the prazosin binding site as shown by their inability to displace the substrate analogue and photoaffinity tag [(125)I]iodoarylazidoprazosin. These studies show that Abcg2, like Mrp4, transports and confers resistance to purine nucleoside analogues and suggest that these two transporters work in parallel to affect drug cytotoxicity and tissue distribution. This new knowledge will facilitate an understanding of how Abcg2 and Mrp4, separately and in combination, protect against purine analogue host toxicity as well as resistance to chemotherapy.


Subject(s)
ATP-Binding Cassette Transporters/physiology , Drug Resistance, Neoplasm , Multidrug Resistance-Associated Proteins/physiology , Purines/chemistry , ATP Binding Cassette Transporter, Subfamily G, Member 2 , Animals , Antineoplastic Agents/pharmacology , Biological Transport , Cell Line, Tumor , Female , Humans , Mice , Mice, Knockout , Spleen/cytology , Substrate Specificity , Tissue Distribution
11.
Mol Pharmacol ; 71(6): 1591-7, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17344354

ABSTRACT

The purpose of the present study was to investigate the role of multidrug resistance-associated protein 4 (MRP4) in the tubular secretion of cephalosporin antibiotics. Most of the injectable cephalosporins have an inhibitory effect on the ATP-dependent uptake of [(3)H]dehydroepiandrosterone sulfate by membrane vesicles expressing hMRP4, whereas cephaloridine, cefsulodin, and cefepime do not. Aminocephalosporins have a weak inhibitory effect. Significant ATP-dependent transport of ceftizoxime (K(m), 18 microM), cefazolin (K(m), 80 microM), cefotaxime, and cefmetazole has been observed only in the membrane vesicles expressing hMRP4. Ceftizoxime and cefazolin were given by a constant intravenous infusion to wild-type and Mrp4(-/-) mice. The steady-state plasma concentrations of ceftizoxime and cefazolin were unchanged in Mrp4(-)(/)(-) mice. The urinary recovery of ceftizoxime was significantly reduced in Mrp4(-/-) mice, whereas it was unchanged for cefazolin. The kidney-to-plasma concentration ratio of ceftizoxime and cefazolin was increased 2.0- and 2.7-fold in Mrp4(-/-) mice, respectively; thus, the renal clearance with regard to the kidney concentration was reduced in Mrp4(-/-) mice, to 7.5 and 34% of the corresponding control values, respectively. These results suggest that Mrp4 is involved in the tubular secretion of ceftizoxime and cefazolin, in concert with basolateral uptake transporters.


Subject(s)
Cefazolin/pharmacokinetics , Ceftizoxime/pharmacokinetics , Kidney/metabolism , Multidrug Resistance-Associated Proteins/metabolism , Animals , Biological Transport , Kidney Tubules, Proximal , Mice
12.
Cancer Lett ; 246(1-2): 34-40, 2007 Feb 08.
Article in English | MEDLINE | ID: mdl-16530326

ABSTRACT

Fms-like tyrosine kinase 1 (Flt-1), a receptor for vascular endothelial growth factor (VEGF), have two isoforms: membrane-bound form (mFlt-1) and soluble form. In the present study, we quantitatively evaluated expression level of mFlt-1 mRNA and VEGF mRNA in non-small cell lung cancer, and demonstrated the clinical significance of the ratio of mFlt-1 mRNA to VEGF mRNA (mFlt-1/VEGF). High mFlt-1/VEGF tumor showed a significantly lower microvessel density (P=0.004), and patients with high mFlt-1/VEGF tumor had a significantly favorable survival (P=0.037). Thus, the ratio of mFlt-1 mRNA to VEGF mRNA was inversely correlated with tumor angiogenesis, and was a significant prognostic factor.


Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Neovascularization, Pathologic/pathology , RNA, Messenger/metabolism , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor Receptor-1/genetics , Aged , Antigens, CD/analysis , Antigens, CD34/analysis , Carcinoma, Non-Small-Cell Lung/blood supply , Carcinoma, Non-Small-Cell Lung/surgery , Endoglin , Female , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Lung Neoplasms/blood supply , Lung Neoplasms/surgery , Male , Membrane Proteins/genetics , Middle Aged , Multivariate Analysis , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/metabolism , Prognosis , RNA, Messenger/genetics , Receptors, Cell Surface/analysis , Survival Analysis
13.
J Surg Oncol ; 95(1): 63-9, 2007 Jan 01.
Article in English | MEDLINE | ID: mdl-17192868

ABSTRACT

BACKGROUND AND OBJECTIVES: In this paper we examined the influence of epidermal growth factor receptor (EGFR) gene mutations on EGFR expression, downstream mediators, and survival in patients with non-small cell lung cancer (NSCLC). METHODS: We retrospectively analyzed the tumors of 53 patients with completely resected pathological stage I-IIIA NSCLC for the presence of EGFR gene mutations, the expression of EGFR mRNA and protein, phosphoryl-Akt, and phosphoryl-mitogen-activated protein kinase (MAPK) using immunostaining, and patients' prognosis. RESULTS: EGFR mutations were associated with elevations in EGFR mRNA (P = 0.004) and protein (P = 0.029) expression, but not with the expression of phosphoryl-Akt or phosphoryl-MAPK. The 5-year survival rate for all patients who exhibited an EGFR mutation was similar to those who were free of such mutations (71% vs. 56%, P = 0.252). However, the 5-year survival rate of patients with either a stage I adenocarcinoma or large cell carcinoma who had an EGFR mutation was significantly greater than for those who did not have such a mutation (92% vs. 57%, P = 0.037). CONCLUSIONS: EGFR gene mutations were significantly associated with higher EGFR expression, but not with p-Akt or p-MAPK status. In early stage NSCLC, the presence of an EGFR gene mutation bode well for the patient's prognosis.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , ErbB Receptors/metabolism , Genes, erbB-1/genetics , Lung Neoplasms/metabolism , Mutation , Adult , Aged , Carcinoma, Non-Small-Cell Lung/genetics , Female , Humans , Lung Neoplasms/genetics , Male , Middle Aged , Mitogen-Activated Protein Kinases/genetics , Phosphorylation , Prognosis , Proto-Oncogene Proteins c-akt/genetics , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction
14.
J Am Soc Nephrol ; 18(1): 37-45, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17135398

ABSTRACT

The role of ATP-binding cassette transporters in the urinary excretion of diuretics was investigated. Significant ATP-dependent uptake of hydrochlorothiazide (HCT) and furosemide was observed in membrane vesicles that expressed multidrug resistance-associated protein 4 (MRP4) and breast cancer resistance protein (BCRP). Unlike taurocholate uptake, S-methylglutathione had no effect on the ATP-dependent uptake of both compounds by MRP4. The functional importance of MRP4 and BCRP in the urinary excretion of HCT and furosemide was investigated using gene knockout mice. The renal clearance of HCT and furosemide was reduced significantly but not abolished in Mrp4 knockout mice compared with wild-type mice (9.0 +/- 0.9 versus 15 +/- 2 ml/min per kg for HCT and 1.9 +/- 0.3 versus 2.7 +/- 0.1 ml/min per kg for furosemide), and the amount of HCT that was associated with the kidney specimens was greater in Mrp4 knockout mice (21 +/- 3 versus 13 +/- 1 nmol/g kidney). In contrast, Bcrp makes only a negligible contribution because the urinary excretion was unchanged in Bcrp knockout mice. Our results suggest that Mrp4, together with other unknown transporters, accounts for the luminal efflux of HCT and furosemide from proximal tubular epithelial cells.


Subject(s)
Furosemide/urine , Hydrochlorothiazide/urine , Multidrug Resistance-Associated Proteins/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 2 , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , Animals , Diuretics/pharmacokinetics , Diuretics/pharmacology , Diuretics/urine , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , Furosemide/pharmacokinetics , Furosemide/pharmacology , Hydrochlorothiazide/pharmacokinetics , Hydrochlorothiazide/pharmacology , Kidney Tubules, Proximal/drug effects , Kidney Tubules, Proximal/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Models, Biological , Multidrug Resistance-Associated Proteins/deficiency , Multidrug Resistance-Associated Proteins/genetics
15.
Mol Pharmacol ; 71(2): 619-27, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17110501

ABSTRACT

Acyclic nucleotide phosphonates (adefovir, cidofovir, and tenofovir) are eliminated predominantly into the urine, and renal failure is their dose-limiting toxicity, particularly for adefovir and cidofovir. In this study, we examined the involvement of multidrug resistance-associated protein (MRP)4 (ABCC4) in their luminal efflux in the kidney. ATP-dependent uptake of adefovir and tenofovir but not cidofovir was observed only in the membrane vesicles expressing MRP4. The ATP-dependent uptake of adefovir and tenofovir by MRP4 was not saturated at 1 mM. The ATP-dependent uptake of adefovir by membrane vesicles expressing MRP4 was osmotic-sensitive. No ATP-dependent uptake of either agent was observed in the membrane vesicles expressing human MRP2 or breast cancer resistance protein. These nucleotide analogs were given to mice by constant intravenous infusion, and the plasma, urine, and tissue concentrations were determined. The kidney accumulation of adefovir and tenofovir was significantly greater in Mrp4 knockout mice (130 versus 66 and 191 versus 87 pmol/g tissue, respectively); thus, the renal luminal efflux clearance was estimated to be 37 and 46%, respectively, of the control. There was no difference in the fraction of mono- and diphosphorylated forms of adefovir in the kidney between wild-type and Mrp4 knockout mice. In mice, cidofovir was also eliminated via the urine by tubular secretion as well as glomerular filtration. There was no change in the kinetic parameters of cidofovir in Mrp4 knockout mice. Our results suggest that MRP4 is involved in the luminal efflux of both adefovir and tenofovir, but it makes only a limited contribution to the urinary excretion of cidofovir.


Subject(s)
Adenine/analogs & derivatives , Multidrug Resistance-Associated Proteins/physiology , Organophosphonates/pharmacokinetics , Adenine/pharmacokinetics , Adenine/urine , Adenosine Triphosphate/pharmacology , Animals , Antiviral Agents/pharmacokinetics , Antiviral Agents/urine , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Drug Resistance, Neoplasm , Female , Humans , Kidney/physiology , Mice , Mice, Knockout , Multidrug Resistance-Associated Protein 2 , Multidrug Resistance-Associated Proteins/deficiency , Organophosphonates/urine , Osmosis , Renal Insufficiency/chemically induced , Tenofovir , Tissue Distribution
16.
Ann Surg Oncol ; 13(11): 1517-23, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17009165

ABSTRACT

BACKGROUND: Maspin is a member of the serpin (serine protease inhibitor) superfamily, and its exact function in the development and progression of malignant tumors remains controversial, though some experimental studies have revealed potential tumor-suppressor activities. In addition, there have been only a few clinical studies on maspin expression in malignant tumors including non-small cell lung cancer (NSCLC). The purpose of this study was to assess maspin expression and its clinical significance in NSCLC. METHODS: A total of 210 consecutive patients with completely resected pathological (p-) stage I-IIIA NSCLC were retrospectively reviewed. Maspin expression along with intratumoral microvessel density, proliferative activity, and p53 status were evaluated immunohistochemically. The incidence of apoptotic cell death was also evaluated. RESULTS: The incidence of strong maspin expression was significantly higher in lung squamous cell carcinoma (56/76, 73.7%; P < .001) than in other histological types. The incidence of aberrant expression of p53 was significantly higher in maspin-strong than in maspin-weak tumors (56.2% and 35.8%, respectively; P = .005). There was no difference in prognosis according to maspin status for all patients. However, for squamous cell carcinoma patients, univariate analysis showed that enhanced maspin expression was a significant factor in predicting a favorable prognosis (5-year survival rates, 70.1% for maspin-strong tumors and 41.5% for maspin-weak tumors; P = .014), which was confirmed in a multivariate analysis (hazard ratio = .475, 95% confidence interval .241-.936; P = .032). CONCLUSIONS: Enhanced maspin expression was a significant and independent factor in predicting a favorable prognosis in lung squamous cell carcinoma.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Lung Neoplasms/metabolism , Serpins/metabolism , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Apoptosis , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Cell Proliferation , Female , Genes, Tumor Suppressor , Humans , Immunoenzyme Techniques , Lung Neoplasms/pathology , Male , Microcirculation , Middle Aged , Prognosis , Retrospective Studies , Survival Rate
17.
Hepatology ; 43(5): 1013-21, 2006 May.
Article in English | MEDLINE | ID: mdl-16628672

ABSTRACT

Mrp4 is a member of the multidrug resistance-associated gene family that is expressed on the basolateral membrane of hepatocytes and undergoes adaptive upregulation in response to cholestatic injury or bile acid feeding. However, the relative importance of Mrp4 in a protective adaptive response to cholestatic injury is not known. To address this issue, common bile duct ligation (CBDL) was performed in wild-type and Mrp4-/- mice and animals followed for 7 days. Histological analysis and serum aminotransferase levels revealed more severe liver injury in the absence of Mrp4 expression. Western analyses revealed that Mrp4, but not Mrp3, was significantly increased after CBDL in wild-type mice. Serum bile acid levels were significantly lower in Mrp4-/- mice than in wild-type CBDL mice, whereas serum bilirubin levels were the same, suggesting that Mrp4 was required to effectively extrude bile acids from the cholestatic liver. Mrp3 and Ostalpha-Ostbeta were upregulated in Mrp4-/- mice but were unable to compensate for the loss of Mrp4. High-performance liquid chromatography analysis on liver extracts revealed that taurine tetrahydroxy bile acid/beta-muricholic acid ratios were increased twofold in Mrp4-/- mice. In conclusion, hepatic Mrp4 plays a unique and essential protective role in the adaptive response to obstructive cholestatic liver injury.


Subject(s)
Cholestasis/physiopathology , Multidrug Resistance-Associated Proteins/deficiency , Animals , Cholestasis/pathology , Cytoprotection , Liver/pathology , Mice , Mice, Inbred C57BL , Multidrug Resistance-Associated Proteins/genetics
18.
Lung Cancer ; 51(3): 323-8, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16406136

ABSTRACT

Maspin is a member of the serpin (serine protease inhibitor) superfamily, and some experimental studies revealed a potential tumor suppressor activity of maspin. To reveal clinical significance of maspin status in non-small cell lung cancer (NSCLC), we quantitatively evaluated maspin gene expression in lung primary tumors cut from a total of 55 resected NSCLC patients. Maspin expression in squamous cell carcinoma (Sq) was significantly higher than that in adenocarcinoma (Ad, p=0.011). Five-year overall survival rates of maspin-high and maspin-low patients were 67.7 and 41.4%, respectively, demonstrating a significant favorable prognosis of maspin-high patients (log-rank, p=0.042). A multivariate analysis confirmed that high maspin expression was an independent and significant factor to predict a favorable overall survival (p=0.031). These results suggested that maspin expression was significantly increased in Sq than in Ad, and that increased maspin expression was a significant factor to predict a favorable prognosis in resected NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung/genetics , Lung Neoplasms/genetics , Serpins/genetics , Aged , Analysis of Variance , Carcinoma, Squamous Cell/metabolism , Chi-Square Distribution , Female , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Humans , Male , Middle Aged , Prognosis , Proportional Hazards Models , Reverse Transcriptase Polymerase Chain Reaction , Survival Rate
19.
Lung Cancer ; 51(1): 79-88, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16225959

ABSTRACT

PURPOSE: MAGE-D4, originally termed MAGE-E1, is a novel MAGE family gene that is expressed at high levels in malignant tumors as compared to normal tissue. The present study was conducted to assess the clinical significance of MAGE-D4 expression in non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Expression of MAGE-D4 protein was estimated by immunohistochemistry and MAGE-D4 mRNA expression was investigated using quantitative reverse transcription-PCR (RT-PCR). RESULTS: We assessed MAGE-D4 expression in NSCLC tissues and was found to be up-regulated in tumor tissues compared with normal lung tissues (mean MAGE-D4/GAPDH values, 0.035 for tumor tissues and 0.009 for normal lung tissues; p=0.002). However, there was no significant difference in MAGE-D4 expression among different pathological stages. The proliferative activity of tumor cells was significantly higher in high MAGE-D4 tumors (mean proliferative indices, 58.3 for high MAGE-D4 tumor levels and 34.0 for low MAGE-D4 tumor levels; p<0.001). In addition, a high MAGE-D4 expression was more frequently seen in squamous cell carcinoma than in adenocarcinoma (p=0.008), and less frequently in well-differentiated tumors than in moderately to poorly differentiated tumors (p=0.036). There was no difference in the postoperative survival between low and high MAGE-D4 patients (5-year survival rates, 65% and 69%, respectively; p=0.742). CONCLUSIONS: MAGE-D4 plays some roles in tumor cells proliferation in NSCLC, but MAGE-D4 expression status did not provided a prognostic significance.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Gene Expression Regulation, Neoplastic , Lung Neoplasms/metabolism , Neoplasm Proteins/genetics , RNA, Messenger/genetics , Animals , Antigens, Neoplasm , Apoptosis , Carcinoma, Non-Small-Cell Lung/immunology , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation , Female , Humans , Immunoblotting , Intracellular Fluid/metabolism , Lung Neoplasms/immunology , Lung Neoplasms/pathology , Mice , Mice, Inbred BALB C , Microscopy, Fluorescence , Neoplasm Proteins/immunology , Neoplasm Proteins/metabolism , Polymerase Chain Reaction , Prognosis
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