Generation of Human iPSC-Derived Intestinal Epithelial Cell Monolayers by CDX2 Transduction.

BACKGROUND & AIMS: To develop an effective and safe orally administered drug, it is important to predict its intestinal absorption rate, intestinal first-pass effect, and drug-drug interactions of orally administered drugs. However, there is no existing model to comprehensively predict the intestinal pharmacokinetics and drug-response of orally administered drugs. In this study, we attempted to generate homogenous and functional intestinal epithelial cells from human induced pluripotent stem (iPS) cells for pharmaceutical research. METHODS: We generated almost-homogenous Villin- and zonula occludens-1 (ZO1)-positive intestinal epithelial cells by caudal-related homeobox transcription factor 2 (CDX2) transduction into human iPS cell-derived intestinal progenitor cells. RESULTS: The drug absorption rates in human iPS cell-derived intestinal epithelial cell monolayers (iPS-IECM) were highly correlated with those in humans (R2=0.91). The expression levels of cytochrome P450 (CYP) 3A4, a dominant drug-metabolizing enzyme in the small intestine, in human iPS-IECM were similar to those in human small intestine in vivo. In addition, intestinal availability in human iPS-IECM (the fraction passing the gut wall: Fg=0.73) was more similar to that in the human small intestine in vivo (Fg=0.57) than to that in Caco-2 cells (Fg=0.99), a human colorectal adenocarcinoma cell line. Moreover, the drug-drug interaction and drug-food interaction could be observed by using our human iPS-IECM in the presence of an inducer and inhibitor of CYP3A4, i.e., rifampicin and grape fruit juice, respectively. CONCLUSION: Taking these results together, we succeeded in generating the human iPS-IECM that can be applied to various intestinal pharmacokinetics and drug-response tests of orally administered drugs.

Analysis of Nonlinear Pharmacokinetics of a Highly Albumin-Bound Compound: Contribution of Albumin-Mediated Hepatic Uptake Mechanism.

The cause of nonlinear pharmacokinetics (PK) (more than dose-proportional increase in exposure) of a urea derivative under development (compound A: anionic compound [pKa: 4.4]; LogP: 6.5; and plasma protein binding: 99.95%) observed in a clinical trial was investigated. Compound A was metabolized by CYP3A4, UGT1A1, and UGT1A3 with unbound Km of 3.3-17.8 µmol/L. OATP1B3-mediated uptake of compound A determined in the presence of human serum albumin (HSA) showed that unbound Km and Vmax decreased with increased HSA concentration. A greater decrease in unbound Km than in Vmax resulted in increased uptake clearance (Vmax/unbound Km) with increased HSA concentration, the so-called albumin-mediated uptake. At 2% HSA concentration, unbound Km was 0.00657 µmol/L. A physiologically based PK model assuming saturable hepatic uptake nearly replicated clinical PK of compound A. Unbound Km for hepatic uptake estimated from the model was 0.000767 µmol/L, lower than the in vitro unbound Km at 2% HSA concentration, whereas decreased Km with increased concentration of HSA in vitro indicated lower Km at physiological HSA concentration (4%-5%). In addition, unbound Km values for metabolizing enzymes were much higher than unbound Km for OATP1B3, indicating that the nonlinear PK of compound A is primarily attributed to saturated OATP1B3-mediated hepatic uptake of compound A.

Newly established ELISA for N-ERC/mesothelin improves diagnostic accuracy in patients with suspected pleural mesothelioma.

Pleural mesothelioma is an aggressive tumor, commonly caused by exposure to asbestos. The prognosis of mesothelioma remains disappointing despite multimodal treatment. We reported previously that N-ERC/mesothelin could be a useful biomarker for the early diagnosis of pleural mesothelioma and developed an enzyme-linked immunosorbent assay (ELISA) system for its detection. However, the reproducibility of our previous 7-16 ELISA system has been revealed to be unsatisfactory. To measure N-ERC/mesothelin more precisely, we developed a new 7-20 ELISA system. The subjects of this study were patients who were referred to our department with suspected pleural mesothelioma. The current study demonstrated that the newly established 7-20 ELISA system improved the sensitivity and specificity for diagnosing pleural mesothelioma compared with the previous system. Moreover, the 7-20 ELISA system showed better reproducibility and displayed the tendency of both higher sensitivity and higher specificity in plasma than in serum. Particularly for the epithelioid type, the area under the curve (AUC) and the diagnostic accuracy of N-ERC/mesothelin were excellent; the AUC was 0.91, the sensitivity was 0.95, and the specificity was 0.76 in plasma. In conclusion, assessment of N-ERC/mesothelin with our newly established 7-20 ELISA system is clinically useful for the precise diagnosis of pleural mesothelioma.

Cystic, nodular and cavitary metastases to the lungs in a patient with endometrial stromal sarcoma of the uterus.

A 57-year-old woman, who had undergone hysterectomy for uterine myoma 11 years earlier presented with cystic, nodular and cavitary lesions simultaneously visible on computed tomography images of the chest. Histological examinations of both the resected lung and past "myoma" specimens demonstrated that the original uterine tumor was a low-grade endometrial stromal sarcoma (ESS) that had metastasized to the lungs. No previous reports have described the coexistence of cystic, nodular and cavitary lesions with pulmonary metastasis of ESS; however, we successfully correlated the radiologic appearance with the corresponding pathologic findings. Medroxyprogesterone acetate therapy has effectively kept the patient asymptomatic for approximately five years.

Substrate- and dose-dependent drug interactions with grapefruit juice caused by multiple binding sites on OATP2B1.

PURPOSE: OATP2B1-mediated grapefruit juice (GFJ)-drug interactions are substrate-dependent; for example, GFJ ingestion significantly reduces bioavailability of fexofenadine, but not pravastatin. In the present study, we aimed to establish whether this observation can be explained by the presence of multiple binding sites (MBS) on OATP2B1. METHODS: OATP2B1-mediated drug uptake was evaluated using a Xenopus oocyte expression system. Drug concentration was quantified by LC/MS/MS analysis. RESULTS: OATP2B1-mediated uptake of pravastatin and fexofenadine exhibited biphasic saturation kinetics, indicating the presence of MBS on OATP2B1. GFJ strongly inhibited pravastatin uptake mediated by the high-affinity site on OATP2B1, while no significant inhibition of the low-affinity site was observed. In contrast, high-affinity transport of fexofenadine was only modestly inhibited by GFJ, while significant inhibition of the low-affinity site was observed. Contribution analysis indicated that both drugs are transported via the low-affinity site on OATP2B1 at therapeutically relevant concentrations. These findings indicate that only fexofenadine is expected to interact with GFJ on OATP2B1 at therapeutic concentrations, in accordance with the clinical observations. CONCLUSION: Substrate- and dose-dependent GFJ-drug interactions mediated by OATP2B1 might be explained in terms of the presence of MBS: interaction occurs only when drug and GFJ components share the same binding site on OATP2B1.

Major active components in grapefruit, orange, and apple juices responsible for OATP2B1-mediated drug interactions.

We aimed to explore the major active components in grapefruit juice (GFJ), orange juice (OJ), and apple juice (AJ) that are responsible for OATP2B1-mediated drug interactions, by means of in vitro studies using Xenopus oocytes expressing OATP2B1 with a typical OATP2B1 substrate, estrone-3-sulfate. All three juices inhibited OATP2B1-mediated estrone-3-sulfate uptake with half-maximum inhibition (IC50 ) values of 0.222% (GFJ), 0.807% (OJ), and 2.27% (AJ). Eight major flavonoids (naringin, naringenin, hesperidin, hesperetin, phloridzin, phloretin, quercetin, and kaempferol) contained in the juices inhibited OATP2B1-mediated estrone-3-sulfate uptake with IC50 values of 4.63, 49.2, 1.92, 67.6, 23.2, 1.31, 9.47, and 21.3 µM, respectively. When the concentration-IC50 ratios ([C]/IC50 ) of these flavonoids in GFJ, OJ, and AJ were calculated, values of [C]/IC50 ≥ 100 were obtained for naringin in GFJ and hesperidin in OJ. No flavonoid in AJ showed a ratio higher than unity. However, significant inhibition of OATP2B1 was observed with a mixture of phloridzin, phloretin, hesperidin, and quercetin at the concentrations present in AJ. In conclusion, our results indicate that naringin and hesperidin are the major OATP2B1 inhibitors in GFJ and OJ, respectively, whereas a combination of multiple components appears to be responsible for OATP2B1 inhibition by AJ.

The N-ERC index is a novel monitoring and prognostic marker for advanced malignant pleural mesothelioma.

BACKGROUND: Although N-ERC/mesothelin (N-ERC) is an attractive diagnostic and treatment monitoring biomarker for malignant pleural mesothelioma (MPM), its clinical utility for predicting the prognosis has not yet been clarified. The aim of this study is to investigate whether the serum N-ERC level can accurately predict the outcome in patients with MPM. METHODS: Twenty-six patients with MPM were enrolled. Serum N-ERC level was measured before and after chemotherapy. The N-ERC index was determined by the logarithm of the division of the N-ERC level after two courses of chemotherapy by the prior level. RESULTS: The median N-ERC index in the partial response (PR) group was significantly lower than that in patients with the stable disease (SD) plus the progressive disease (PD) group. The overall survival in the group whose median N-ERC index was lower than its median value was significantly longer than the group whose median N-ERC index was higher than its median value. CONCLUSIONS: The N-ERC index is therefore considered to be a useful biomarker for predicting not only the chemotherapeutic response, but also the prognosis in patients with advanced MPM.

Major active components in grapefruit, orange, and apple juices responsible for OATP2B1-mediated drug interactions.

We aimed to explore the major active components in grapefruit juice (GFJ), orange juice (OJ), and apple juice (AJ) that are responsible for OATP2B1-mediated drug interactions, by means of in vitro studies using Xenopus oocytes expressing OATP2B1 with a typical OATP2B1 substrate, estrone-3-sulfate. All three juices inhibited OATP2B1-mediated estrone-3-sulfate uptake with half-maximum inhibition (IC(50) ) values of 0.222% (GFJ), 0.807% (OJ), and 2.27% (AJ). Eight major flavonoids (naringin, naringenin, hesperidin, hesperetin, phloridzin, phloretin, quercetin, and kaempferol) contained in the juices inhibited OATP2B1-mediated estrone-3-sulfate uptake with IC(50) values of 4.63, 49.2, 1.92, 67.6, 23.2, 1.31, 9.47, and 21.3 µM, respectively. When the concentration-IC(50) ratios ([C]/IC(50) ) of these flavonoids in GFJ, OJ, and AJ were calculated, values of [C]/IC(50) ≥ 100 were obtained for naringin in GFJ and hesperidin in OJ. No flavonoid in AJ showed a ratio higher than unity. However, significant inhibition of OATP2B1 was observed with a mixture of phloridzin, phloretin, hesperidin, and quercetin at the concentrations present in AJ. In conclusion, our results indicate that naringin and hesperidin are the major OATP2B1 inhibitors in GFJ and OJ, respectively, whereas a combination of multiple components appears to be responsible for OATP2B1 inhibition by AJ.

Long-lasting inhibitory effect of apple and orange juices, but not grapefruit juice, on OATP2B1-mediated drug absorption.

Enzyme-based grapefruit juice (GFJ)-drug interactions are mainly due to mechanism-based irreversible inhibition of metabolizing enzyme CYP3A4 by GFJ components, but the transporter organic anion transporting polypeptide (OATP)2B1 is also a putative site of interaction between drugs and fruit juices (FJ) in the absorption process. Here we aimed to investigate the effect of preincubation with FJ on OATP2B1-mediated transport of drugs in vitro. When OATP2B1-expressing Xenopus oocytes were preincubated with GFJ, orange juice (OJ), or apple juice (AJ), AJ induced a remarkable decrease in OATP2B1-mediated estrone-3-sulfate uptake in a concentration-dependent manner (IC(50) = 1.5%). A similar but less potent effect was observed with OJ (IC(50) = 21%), whereas GFJ had no effect. Similar results were obtained in preincubation studies using fexofenadine. Preincubation with OJ and AJ resulted in time-dependent inhibition of OATP2B1. Again, AJ had the more potent effect; its action lasted for at least 240 minutes, suggesting that AJ irreversibly inhibits OATP2B1-mediated drug uptake. Kinetic analysis revealed that coincubation and preincubation with AJ reduced OATP2B1-mediated estrone-3-sulfate uptake via competitive and noncompetitive mechanisms, respectively. Thus, OATP2B1 is functionally impaired through both competitive and long-lasting inhibition mechanisms by AJ and OJ, but not GFJ. Interestingly, although GFJ but not AJ is able to irreversibly inhibit CYP3A4, in the case of OATP2B1, AJ but not GFJ has a long-lasting inhibitory effect. Accordingly, complex FJ-drug interactions may occur in vivo, and their clinical significance should be examined.

Coexistence of pyriform sinus fistula, ectopic lingual thyroid, and ectopic cervical thymus.

OBJECTIVE: We report an extremely rare case of coexistence of pyriform sinus fistula, ectopic lingual thyroid, and ectopic cervical thymus. CASE REPORT: A 16-year-old girl with ectopic lingual thyroid had suffered repetitive painful swelling in the left anterior neck. Barium swallow radiography and computed tomography revealed a fistula arising from the pyriform sinus running down to the anterior neck. She underwent transcervical fistulectomy with preservation of the recurrent laryngeal nerve. Histopathological examination of the surgical specimen showed coexisting thymic tissue. CONCLUSION: This illustrative case exemplifies the different embryological origin of the thyroid from that of the third and fourth pharyngeal pouch derivatives.

Functional pleiotropy of organic anion transporting polypeptide OATP2B1 due to multiple binding sites.

The purpose of this study was to examine whether the presence of multiple binding sites can explain the pleiotropy of substrate recognition by OATP2B1, using Xenopus oocytes expressing OATP2B1. OATP2B1-mediated uptake of estrone-3-sulfate apparently exhibited biphasic saturation kinetics, with Km values of 0.10 ± 0.05 and 29.9 ± 12.1 µM and Vmax values of 14.1 ± 6.4 and 995 ± 273 fmol/min/oocyte for high- and low-affinity sites, respectively. Contribution analysis revealed that transport of estrone-3-sulfate mediated by high- and low-affinity sites on OATP2B1 could be evaluated at the concentrations of 0.005 and 50 µM, respectively. pH-dependence study of OATP2B1-mediated estrone-3-sulfate uptake suggested that high- and low-affinity sites show different pH sensitivity. When the inhibitory effect of 12 compounds on estrone-3-sulfate uptake by high- and low-affinity sites on OATP2B1 was examined, 4 compounds appeared to be inhibitors of the high-affinity site on OATP2B1. Two other compounds appeared to be inhibitors for the low-affinity site and four others were inhibitory at both sites. These results indicated the presence of multiple binding sites on OATP2B1 with different affinity for drugs. Accordingly, it is likely that drug-drug and drug-beverage interactions occur only when two drugs share the same binding site on OATP2B1.

Prediction model for hearing outcome in patients with idiopathic sudden sensorineural hearing loss.

The aim of this study is to develop a regression model for predicting hearing outcome in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). A total of 174 consecutive patients with ISSNHL (average of the hearing levels at 250, 500, 1,000, 2,000, and 4,000 Hz was ≥40 dB; time from onset to treatment was ≤30 days) were retrospectively analyzed. They received steroid administration (400 mg/day of hydrocortisone sodium succinate followed by tapered doses) in combination with hyperbaric oxygen therapy. The hearing improvement rate compared to the unaffected contralateral ear was calculated. Correlations between the hearing improvement rate and four prognostic factors (patient's age, days from onset to treatment, initial hearing level, and the presence of vertigo) were examined by simple and multiple regression analyses. In the simple regression analysis, significant correlations were observed between the hearing improvement rate and all four prognostic factors. In the multiple regression analysis, the correlation was significant for patient's age, days from onset to treatment, and the presence of vertigo with partial correlation coefficients of -0.221, -0.324, and -0.329, respectively, but was not significant for the initial hearing level. We subsequently formulated a multiple regression equation for predicting the hearing improvement rate. The multiple correlation coefficient was 0.495 with a p value of 1.42 × 10(-9). Using this regression model, the hearing improvement rate is still difficult to predict with 95% probability, but is predictable with 70% probability.

Phosphodiesterase 4 inhibitor GPD-1116 markedly attenuates the development of cigarette smoke-induced emphysema in senescence-accelerated mice P1 strain.

Phosphodiesterase 4 (PDE4) is an intracellular enzyme specifically degrading cAMP, a second messenger exerting inhibitory effects on many inflammatory cells. To investigate whether GPD-1116 (a PDE4 inhibitor) prevents murine lungs from developing cigarette smoke-induced emphysema, the senescence-accelerated mouse (SAM) P1 strain was exposed to either fresh air or cigarette smoke for 8 wk with or without oral administration of GPD-1116. We confirmed the development of smoke-induced emphysema in SAMP1 [air vs. smoke (means +/- SE); the mean linear intercepts (MLI), 52.9 +/- 0.8 vs. 68.4 +/- 4.2 microm, P < 0.05, and destructive index (DI), 4.5% +/- 1.3% vs. 16.0% +/- 0.4%, P < 0.01]. Emphysema was markedly attenuated by GPD-1116 (MLI = 57.0 +/- 1.4 microm, P < 0.05; DI = 8.2% +/- 0.6%, P < 0.01) compared with smoke-exposed SAMP1 without GPD-1116. Smoke-induced apoptosis of lung cells were also reduced by administration of GPD-1116. Matrix metalloproteinase (MMP)-12 activity in bronchoalveolar lavage fluid (BALF) was increased by smoke exposure (air vs. smoke, 4.1 +/- 1.1 vs. 40.5 +/- 16.2 area/microg protein; P < 0.05), but GPD-1116 significantly decreased MMP-12 activity in smoke-exposed mice (5.3 +/- 2.1 area/microg protein). However, VEGF content in lung tissues and BALF decreased after smoke exposure, and the decrease was not markedly restored by oral administration of GPD-1116. Our study suggests that GPD-1116 attenuates smoke-induced emphysema by inhibiting the increase of smoke-induced MMP-12 activity and protecting lung cells from apoptosis, but is not likely to alleviate cigarette smoke-induced decrease of VEGF in SAMP1 lungs.

[Clinical study of early laryngeal cancer].

We retrospectively analyzed 71 consecutive cases of early laryngeal cancer (stage I or II) that had undergone primary treatment in our department between 1999 and 2004. There were 68 males and 3 females, and their ages ranged from 40 to 85 years of age (average; 67.7 years). Eight patients had the supraglottic type, 61 had the glottic type, and 2 had the subglottic type. Chemoradiotherapy was performed as the primary treatment except in the patients with glottic T1a cancer, who received radiotherapy alone. The 5-year survival rates was 91.1% for glottic cancer (T1a: 100%, T1b: 92.3%, T2: 85.8%) and 75.0% for supraglottic cancer. The local control rate of glottic cancer was 79.6% (T1a: 80.0%, T1b: 74.0%, T2: 85.2%), and significantly higher than that of supraglottic cancer (56.2%, p < 0.05). The laryngeal preservation rate was 84.4% in glottic cancer (T1a: 100%, T1b: 76.9%, T2: 77.5%) and 58.3% in supraglottic cancer, and the difference between T1a and T2 glottic cancer was significant (p < 0.05). Local recurrence and cervical lymph node metastasis were seen in 9 patients and 6 patients, respectively. Distant metastasis occurred in 4 patients, all of whom had the glottic type. Four patients died of their disease, and distant metastasis was the major cause of death in 3 of them. These results indicate that additional treatment should be performed in cases in which radiotherapy/chemoradiotherapy is ineffective and that both in the early stages glottic and supraglottic cancers can be successfully treated by radiotherapy/chemoradiotherapy. The results also suggested that the survival of patients with early laryngeal cancer depends on whether they develop distant metastasis. Introduction of adjuvant chemotherapy to improve their prognosis remains to be assessed.

Hyperbaric oxygen and steroid therapy for idiopathic sudden sensorineural hearing loss.

In our controlled retrospective analysis of medical records in tertiary care academic medical center, we aimed to investigate the therapeutic effects of hyperbaric oxygen (HBO) therapy combined with steroid administration for idiopathic sudden sensorineural hearing loss (ISSNHL) in comparison with that of steroid administration alone. Our subjects were 130 consecutive inpatients with ISSNHL (hearing levels >/=40 dB; time from the onset of hearing loss to the start of treatment /=80 dB, the hearing improvement rate was significantly higher in the HBO group than in the steroid group (51.1 +/- 7.0% vs. 27.1 +/- 7.8%; P < 0.05), while in patients whose initial hearing levels were <80 dB, hearing outcomes were not statistically different between the two groups. In both the HBO and steroid groups, patients with initial hearing levels of <80 dB showed a better hearing improvement rate than those with initial hearing levels of >/=80 dB. In conclusion HBO therapy shows a significant additional effect in combination with steroid therapy for ISSNHL, particularly in patients with severe hearing loss.

Intense accumulation of gallium-67 citrate in pancreatic endocrine tumor.

We report intense accumulation of gallium-67 (Ga-67) citrate in a pancreatic endocrine tumor. A 69-year-old woman was admitted because of cough, fever, and weight loss. An abdominal enhanced computed tomography (CT) scan revealed a large tumor located between the liver and pancreas as well as swollen paraaortic lymph nodes. Whole-body scintigraphy with Ga-67 revealed intense accumulation in the upper abdomen corresponding to the mass, as well as in the midabdomen and the mediastinal lesion. Percutaneous needle biopsy was performed, and the diagnosis was adenocarcinoma of the pancreas. The patient's condition deteriorated, and she died 2 months after admission. The pathological examination at autopsy revealed a pancreatic endocrine tumor. No report has described findings of Ga-67 citrate scintigraphy of pancreatic endocrine tumors. Pancreatic endocrine tumor should be included in a differential diagnosis when such scintigraphic findings are encountered.

Senescence marker protein-30 protects mice lungs from oxidative stress, aging, and smoking.

RATIONALE: Senescence marker protein-30 (SMP30) is a multifunctional protein providing protection to cellular functions from age-associated deterioration. We previously reported that SMP30 knockout (SMP30Y/-) mice are capable of being novel models for senile lung with age-related airspace enlargement and enhanced susceptibility to harmful stimuli. OBJECTIVES: Aging and smoking are considered as major contributing factors for the development of pulmonary emphysema. We evaluated whether SMP30Y/- mice are susceptible to oxidative stress associated with aging and smoking. METHODS: Age-related changes of protein carbonyls in lung tissues from the wild-type (SMP30Y/+) and SMP30Y/- mice were evaluated. Both strains were exposed to cigarette smoke for 8 wk. Histopathologic and morphologic evaluations of the lungs, protein carbonyls and malondialdehyde in the lung tissues, total glutathione content in the bronchoalveolar lavage fluid, and degree of apoptosis of lung cells were determined. MEASUREMENTS AND MAIN RESULTS: In the lungs of SMP30Y/- mice, protein carbonyls tended to increase with aging and were significantly higher than the age-matched SMP30Y/+ mice. Cigarette smoke exposure generated marked airspace enlargement (23.3% increase of the mean linear intercepts) with significant parenchymal destruction in the SMP30Y/- mice but not in the SMP30Y/+ mice (5.4%). The protein carbonyls, malondialdehyde, total glutathione, and apoptosis of lung cells were significantly increased after 8-wk exposure to cigarette smoke in the SMP30Y/- mice. CONCLUSIONS: Our results suggest that SMP30 protects mice lungs from oxidative stress associated with aging and smoking. The SMP30Y/- mice could be useful animal models for investigating age-related lung diseases, including cigarette smoke-induced pulmonary emphysema.

Management of malignant pericardial effusion with instillation of mitomycin C in non-small cell lung cancer.

BACKGROUND: To evaluate the clinical efficacy and safety of mitomycin C in the local control of malignant pericardial effusion, we carried out a trial of pericardial drainage with local instillation of mitomycin C in eight patients who suffered from cardiac tamponade or symptomatic large pericardial effusion caused by advanced non-small cell lung cancer. METHODS: After complete removal of the pericardial effusion by an ultrasound-guided inserted catheter, 2 mg of mitomycin C was instilled into the pericardial space via the catheter. RESULTS: The drainage catheter was successfully removed in all patients. The duration of pericardial drainage ranged from 7 to 14 days (median 10.5 days). Six of the eight patients achieved a complete remission of pericardial effusions without any adverse effects. CONCLUSION: Intrapericardial instillation of 2 mg of mitomycin C was feasible and demonstrated a promising response against malignant pericardial effusion resulting from non-small cell lung cancer.