Efficacy and safety of early initiation of eplerenone treatment in patients with acute heart failure (EARLIER trial): a multicenter, randomized, double-blind, placebo-controlled trial

AIMS

A mineralocorticoid receptor antagonist (MRA) is effective in patients with chronic heart failure; however, the effects of the early initiation of an MRA in patients with acute heart failure (AHF) have not been elucidated.

METHODS AND RESULTS

In this multicenter, randomized, double-blind, placebo-controlled, parallel-group study, we focused on the safety and effectiveness of the treatment with eplerenone, a selective MRA in 300 patients with AHF, that is, 149 in the eplerenone group and 151 in the placebo group in 27 Japanese institutions. The key inclusion criteria were (1) patients aged 20 years or older and (2) those with left ventricular ejection fraction of ≤ 40%. The primary outcome was a composite of cardiac death or first re-hospitalization due to cardiovascular disease within 6 months. The mean age of the participants was 66.8 years, 27.3% were women, and the median levels of brain natriuretic peptide were 376.0 pg/mL. The incidences of the primary outcome were 19.5% in the eplerenone group and 17.2% in the placebo group (hazard ratio (HR): 1.09, 95% confidence interval (CI): 0.642-1.855). In prespecified secondary outcomes, HR for the composite endpoint, cardiovascular death, or first re-hospitalization due to heart failure (HF) within 6 months was 0.55 (95% CI: 0.213 to 1.434). The safety profile for eplerenone was as expected.

CONCLUSION

The early initiation of eplerenone in patients with AHF could safely be utilized. The reduction of the incidence of a composite of cardiovascular death or first re-hospitalization for cardiovascular diseases by eplerenone is inconclusive because of inadequate power.

Cardiovascular Outcomes in Patients With Previous Myocardial Infarction and Mild Diabetes Mellitus Following Treatment With Pioglitazone: Reports of a Randomised Trial From The Japan Working Group for the Assessment Whether ioglitazone rotects DM Patients gainst e-Infarction (PPAR Study)

BACKGROUND

Secondary prevention in patients with myocardial infarction (MI) is critically important to prevent ischaemic heart failure and reduce social burden. Pioglitazone improves vascular dysfunction and prevents coronary atherosclerosis, mainly via anti-inflammatory and antiatherogenic effects by enhancing adiponectin production in addition to antihyperglycemic effects, thus suggesting that pioglitazone attenuates cardiovascular events in patients with mild (HbA1c levels < 6·5%) diabetes mellitus (DM). Therefore, we evaluated the effects of pioglitazone on cardiovascular events in patients with both previous MI and mild DM.

METHODS

In this multicentre, prospective, randomised, open, blinded-endpoint trial, we randomly assigned 630 patients with mild DM with a history of MI to undergo either DM therapy with (pioglitazone group) or without (control group) pioglitazone. DM was diagnosed using the 75-g oral glucose tolerance test, and mild DM was defined if HbA1c level was < 6·5%. The primary endpoint was the composite of cardiovascular death and hospitalisation caused by acute MI, unstable angina, coronary revascularisation (including percutaneous coronary intervention and cardiac bypass surgery), and stroke.

FINDINGS

HbA1C levels were 5·9 and 5·8% (p = 0·71) at baseline and 6·0 and 5·8% (p < 0·01) at 2 years for the control and pioglitazone groups, respectively.The primary endpoint was observed in 14·2% and 14·1% patients in the control and pioglitazone groups during two years (95% confidential interval (CI):0.662-1·526, p = 0·98), respectively; the incidence of MI and cerebral infarction was 0·3% and 2·2% (95%CI: 0·786-32·415, p = 0·09) and 1·0% and 0·3% (95%CI: 0·051-3·662, p = 0·44), respectively. Post-hoc analyses of the 7-year observation period showed that these trends were comparable (21·9% and 19·2% in the control and pioglitazone groups, 95%CI: 0.618-1·237, p = 0·45).

INTERPRETATION

Pioglitazone could not reduce the occurrence of cardiovascular events in patients with mild DM and previous MI.

Oncogenic signaling by Kit tyrosine kinase occurs selectively on the Golgi apparatus in gastrointestinal stromal tumors

Gastrointestinal stromal tumors (GISTs) are caused by gain-of-function mutations in the Kit receptor tyrosine kinase. Most primary GIST patients respond to the Kit inhibitor imatinib, but this drug often becomes ineffective because of secondary mutations in the Kit kinase domain. The characteristic intracellular accumulation of imatinib-sensitive and -resistant Kit protein is well documented, but its relationship to oncogenic signaling remains unknown. Here, we show that in cancer tissue from primary GIST patients as well as in cell lines, mutant Kit accumulates on the Golgi apparatus, whereas normal Kit localizes to the plasma membrane (PM). In imatinib-resistant GIST with a secondary Kit mutation, Kit localizes predominantly on the Golgi apparatus. Both imatinib-sensitive and imatinib-resistant Kit (Kit(mut)) become fully auto-phosphorylated only on the Golgi and only if in a complex-glycosylated form. Kit(mut) accumulates on the Golgi during the early secretory pathway, but not after endocytosis. The aberrant kinase activity of Kit(mut) prevents its export from the Golgi to the PM. Furthermore, Kit(mut) on the Golgi signals and activates the phosphatidylinositol 3-kinase–Akt (PI3K–Akt) pathway, signal transducer and activator of transcription 5 (STAT5), and the Mek–Erk pathway. Blocking the biosynthetic transport of Kit(mut) to the Golgi from the endoplasmic reticulum inhibits oncogenic signaling. PM localization of Kit(mut) is not required for its signaling. Activation of Src-family tyrosine kinases on the Golgi is essential for oncogenic Kit signaling. These results suggest that the Golgi apparatus serves as a platform for oncogenic Kit signaling. Our study demonstrates that Kit(mut)’s pathogenicity is related to its mis-localization, and may offer a new strategy for treating imatinib-resistant GISTs.

Calibration of the microcalorimeter spectrometer on-board the Hitomi (Astro-H) observatory (invited)

The Hitomi Soft X-ray Spectrometer (SXS) was a pioneering non-dispersive imaging x-ray spectrometer with 5 eV FWHM energy resolution, consisting of an array of 36 silicon-thermistor microcalorimeters at the focus of a high-throughput soft x-ray telescope. The instrument enabled astrophysical plasma diagnostics in the 0.3-12 keV band. We introduce the SXS calibration strategy and corresponding ground calibration measurements that took place from 2012-2015, including both the characterization of the microcalorimeter array and measurements of the x-ray transmission of optical blocking filters.

Effects of bisphosphonates on human esophageal squamous cell carcinoma cell survival

Esophageal squamous cell carcinoma (ESCC) is one of the most malignant cancers in Japan. Anticancer chemotherapy has been useful for ESCC treatment. However, therapeutic options are limited. Recently, bisphosphonates (BPs), which are osteoporosis drugs, have shown anticancer effects in several cancer cell lines, but the effects against ESCC cell lines are unknown. In this study, we examined the cytotoxic effects of BPs and their mechanisms of cytotoxicity in human ESCC cell lines. A first-generation BP (etidronate), two second-generation BPs (alendronate and pamidronate), and two third-generation BPs (risedronate and zoledronate) were used in this study. All BPs, except etidronate, were cytotoxic, as indicated by increased caspase-3/7 activity and numbers of Annexin-fluorescein isothiocyanate positive cells in ESCC cell lines. From cell cycle analysis, G0/G1-phase arrest was observed upon treatment with second- and third-generation BPs. In addition, Cyclin D1 protein expression levels were decreased by second- and third-generation BP treatment. Although squalene and trans, trans-farnesol minimally affected BP cytotoxicity, treatment with geranylgeraniol inhibited BP cytotoxicity almost completely. We concluded that second- and third-generation BPs are cytotoxic to ESCC cell lines as they induce apoptosis and inhibit the cell cycle through mevalonate pathway inhibition. Therefore, BP treatment may be a beneficial therapy in ESCC patients.

Addition of cilostazol to aspirin therapy for secondary prevention of cardiovascular and cerebrovascular disease in patients undergoing percutaneous coronary intervention: A randomized, open-label trial

BACKGROUND

Patients with established coronary artery disease are at increased risk for future ischemic events and require secondary prevention for systemic vascular disease. We performed a randomized clinical trial to evaluate the impact of cilostazol on cardiovascular and cerebrovascular disease in patients undergoing percutaneous coronary intervention.

METHODS

A total of 514 patients who had undergone coronary stent implantation >6 months previously and were thought to no longer need dual antiplatelet therapy with aspirin and a thienopyridine were randomly assigned to receive aspirin plus cilostazol therapy or aspirin therapy alone after discontinuation of thienopyridine therapy. The primary efficacy end point was a composite of all-cause death, myocardial infarction, stroke, or cardiovascular or cerebrovascular revascularization at 2 years after randomization. The main safety end point was major or minor bleeding, according to the Thrombolysis in Myocardial Infarction bleeding definition.

RESULTS

At 2 years, follow-up clinical data were available for 98.1% of patients. The primary efficacy end point occurred in 13.9% of the aspirin plus cilostazol group versus 22.1% of the aspirin-only group (hazard ratio 0.61, 95% CI 0.40-0.93, P = .021). The rate of major or minor bleeding was not significantly different between the aspirin plus cilostazol and aspirin-only groups (1.6% and 4.0%, respectively, hazard ratio 0.40, 95% CI 0.13-1.28, P = .12).

CONCLUSIONS

In patients who underwent coronary stent implantation, the addition of cilostazol to aspirin therapy was associated with lower rates of cardiovascular and cerebrovascular events at 2 years compared with aspirin monotherapy.

Well-defined SiO2-coated Fe2Co nanoparticles prepared by reduction with CaH2

Well-defined SiO₂-coated Fe₂Co nanoparticles can be prepared by the reduction of SiO₂-coated CoFe₂O₄ nanoparticles with CaH₂ even at 250 °C.

Tunable terahertz emission from the intrinsic Josephson junctions in acute isosceles triangular Bi₂Sr₂CaCu₂O₈+δ mesas

In order to determine if the mesa geometry might affect the properties of the coherent terahertz (THz) radiation emitted from the intrinsic Josephson junctions in mesas constructed from single crystals of the high-temperature superconductor, Bi₂Sr₂CaCu₂O₈+δ, we studied triangular mesas. For equilateral triangular mesas, the observed emission was found to be limited to the single mesa TM(1,0) mode. However, tunable radiation over the range from 0.495 to 0.934 THz was found to arise from an acute isosceles triangular mesa. This 47% tunability is the widest yet observed from the outer current-voltage characteristic branch of such mesas of any geometry. Although the radiation at a few of the frequencies in the tunable range appear to have been enhanced by cavity resonances, most frequencies are far from such resonance frequencies, and can only be attributed to the ac-Josephson effect.

A case of Helicobacter pylori infection complicated with gastric cancer, gastric mucosa-associated lymphoid tissue lymphoma, and idiopathic thrombocytopenic purpura successfully treated with laparoscopy-assisted total gastrectomy and splenectomy

Helicobacter pylori infection plays a key role in the pathogenesis of H. pylori-associated diseases, including gastroduodenal and non-gastroduodenal diseases. A 71-year-old man was evaluated for a positive fecal occult blood test by upper gastrointestinal endoscopy, which revealed H. pylori infection, two adenocarcinomas and two gastric mucosa-associated lymphoid tissue lymphomas. Hematological examination revealed low platelet-count, elevated platelet-associated immunoglobulin G and anti-H. pylori immunoglobulin G antibodies. We diagnosed H. pylori infection complicated by simultaneous occurrence of gastric cancer, gastric mucosa-associated lymphoid tissue lymphoma, and idiopathic thrombocytopenic purpura. These diseases were successfully treated with laparoscopy-assisted total gastrectomy and splenectomy, and there was no evidence of recurrence for about 2 years. This is the first reported case of H. pylori infection complicated by these three diseases and cured with laparoscopic surgery.

Prolonged carotid sinus reflex is a risk factor for contrast-induced nephropathy following carotid artery stenting

BACKGROUND AND PURPOSE

Although many studies have demonstrated that CIN is associated with in-hospital and long-term mortality, the incidence of CIN following CAS is unclear. We investigated the incidence of CIN, defined as an increase from a baseline creatinine value of at least 0.5 mg/dL or 25% within 72 hours of contrast administration, and we also examined renal function in the late phase after CAS.

MATERIALS AND METHODS

We examined 80 patients who underwent CAS between April 2005 and December 2009. Clinical background, laboratory data, contrast volume, and clinical course were collected and analyzed.

RESULTS

The incidence of CIN was 8.8% (7/80), and no patients required hemodialysis. In the group that developed CIN, prolonged CSR after CAS was found in 57.1% (4/7) of cases; this incidence differed significantly (P = .001) from that in the group without development of CIN. Neither preoperative renal function, contrast volume, nor history was related to the incidence of CIN, while on multivariate analysis, prolonged CSR was found to be an independent risk factor for CIN. The incidence of elevation in creatinine values at 6 months after CAS was 8.2% (6/73). All patients who developed delayed renal impairment had pre-existing CKD; this finding differed significantly (P = .04) from that in the group without development of delayed renal impairment.

CONCLUSIONS

Because patients who develop prolonged CSR after CAS are at increased risk of perioperative major adverse clinical events including CIN, patients at high risk for this condition should be carefully managed to prevent increased morbidity and mortality.

The effect of recombinant aminopeptidase A on hypertension in spontaneously hypertensive rats: its effect in comparison with candesartan

An understanding of aminopeptidase A in hypertension is important, given its ability to cleave the N-terminal aspartic acid of potent vasoconstrictor angiotensin II. However, the role of aminopeptidase A in hypertension has received limited attention. Because we have succeeded in producing recombinant human aminopeptidase A, the effect of aminopeptidase A on systolic blood pressure in the spontaneously hypertensive rat was examined. Aminopeptidase A of 0.016 mg/kg was administrated intravenously to spontaneously hypertensive rats and blood pressure was monitored for 72 h. For repeated administration, aminopeptidase A doses of 0.016 mg/kg and 0.1-mg/kg doses of candesartan (an angiotensin II receptor 1 subtype blocker) were administrated daily in spontaneously hypertensive rats and blood pressure was monitored for 5 d. Bolus intravenous injection of aminopeptidase A at a dose of 0.016 mg/kg significantly decreased systolic blood pressure for 36 h in spontaneously hypertensive rats. A comparison of the antihypertensive effects of aminopeptidase A versus candesartan in spontaneously hypertensive rats showed that the effective dose of aminopeptidase A was about one-tenth that of candesartan. These results suggest the novel approach of utilizing aminopeptidase A to treat hypertension by degrading circulating angiotensin II before it binds to the receptor 1 subtype.

CDK2 and CDK1 specific activities: A novel prognostic indicator in early breast cancer

10592

Background: Cyclin-dependent kinases (CDKs) are expressed almost constantly but their activities change according to cell cycle phase. We studied the specific activity (SA; activity/expression) of CDKs to accurately evaluate their role in cell proliferation. We focused on the ratio of CDK2 SA to CDK1 SA because this ratio has been associated with rapid tumor growth in human breast cancer xenografts. Our goal was to investigate the prognostic significance of CDK2/1 ratio in node-negative breast cancer. Methods: We used a novel assay to measure SAs of CDK2 and CDK1 in 365 primary breast tumors. All tumors were histologically confirmed invasive breast cancer without lymph node involvement. The primary endpoint was relapse-free survival (RFS). Cut-off values for CDK2/1 ratio were defined as those points that best discriminated groups according to RFS. Tumors were grouped as low (136pts), intermediate (84pts), and high (145pts) CDK2/1 ratio. The median follow-up was 59 months (range 4–102). Results: Pts characteristics are described as follows: menopausal status: pre- 42%, post- 58%; tumor size: =20mm 48%, >20mm 52%; histologic grade (HG): I 28%, II 47%, III 23%; ER: (+) 57%, (-) 42%; PR: (+) 51%, (-) 48%. Pts with HG III or high CDK2/1 ratio showed significantly lower 5y-RFS rates than those with HG I/II or low/intermediate CDK2/1 ratio, respectively (HG: I 97%, II 91%, III 85%, P=0.040; CDK2/1 ratio: low 97%, intermediate 92%, high 85%, P=0.017). In univariate analysis, PR (- vs +, P=0.088) had a tendency to associate with relapse, and HG (III vs I, P=0.024) and CDK2/1 ratio (high vs low, P=0.011) also had a significant correlation with relapse. However, only CDK2/1 ratio showed a significant independent prognostic indicator in multivariate analysis (hazard ratio 2.86, 95% CI 1.25–6.58, P=0.01). More important, among women (n=185) with hormone receptor (HR) positive disease given adjuvant hormone therapy alone, who have had no useful factors to predict their outcomes, high CDK2/1 ratio was also associated with worse prognosis than low CDK2/1 ratio (5y-RFS 84% vs 100%, P=0.007). Conclusions: For patients with node- negative disease, especially those with HR positive tumors given adjuvant hormone therapy alone, the CDK2/1 ratio might be useful as a routine laboratory test to predict outcome.

No significant financial relationships to disclose.

Antacid interaction with new quinolones: dose regimen recommendations based on pharmacokinetic modeling of clinical data for ciprofloxacin, gatifloxacin and norfloxacin and metal cations

OBJECTIVE

New quinolones (NQs) are widely used to treat various infections. However, concomitant oral administration of metal cations may decrease absorption of NQs and consequently decrease their blood concentration and pharmacological effect. A convenient approach to avoid this interaction is to separate the dosages by a certain interval. In this study, we aimed to develop a novel pharmacokinetic model to describe NQs-metal cation interactions in order to estimate the optimal dosing interval.

METHODS

Plasma concentration-time profiles of NQs after administration without or with metal cations at various dosing intervals were collected from the literature and analyzed with a pharmacokinetic model incorporating the formation ofNQs-metal cations complex. The model was fitted to the reported time profiles ofciprofloxacin (CPFX) plasma concentration after concomitant administration with aluminum hydroxide/magnesium hydroxide antacid (Al/Mg antacid; Maalox, Maalox70) at various dosing intervals to obtain the pharmacokinetic parameters of CPFX. Model analysis was also carried out for gatifloxacin (GFLX) and norfloxacin (NFLX).

RESULTS

The developed model could adequately explain the interactions in all the combinations investigated. The model predicted, in the cases of usual doses of CPFX with Maalox, GFLX with Maalox70 and NFLX with sucralfate, that the NQ should be administered 4.5, 4.5 and 3.5 hours after, or 1, 1 and 0.5 hours before the administration of metal cations, respectively, to ensure 90% of control absorption.

CONCLUSIONS

The developed model can adequately describe the extent of interaction between NQs and metal cations, and should be clinically useful to design dosage regimens to circumvent the interaction.

Dosage adjustment of quinolone antibiotics and angiotensin-converting enzyme inhibitors in patients with renal dysfunction

The aim of this study was to verify an approach for calculating pharmacokinetic parameters suitable for adjusting dosage regimens in patients with renal dysfunction. We carried out a retrospective analysis of the pharmacokinetic profiles of 12 new quinolone antibiotics and 11 angiotensin-converting enzyme inhibitors (ACEIs) in patients with normal and impaired renal function to obtain the renal excretion ratio (R(renal)) of each drug. We demonstrated that the pharmacokinetics of each drug in a patient with renal dysfunction can be adequately estimated using the R(renaI) value of each drug together with the creatinine clearance as an index of the individual's renal function. Using the R(renaI) value obtained, we could successfully simulate pharmacokinetic profiles of the drugs in publications other than that used to obtain the R(renal) values. On the other hand, age-related changes in the pharmacokinetics of new quinolone antibiotics are not always adequately predicted using the R(renal) value compared to using creatinine clearance alone as an index, and the reasons for this are not fully understood. These results demonstrate that dosage regimens of quinolone antibiotics and ACEIs in patients with renal dysfunction can be adequately optimized using the R(renal) value for each drug using the present approach.

Importance of lymph vessels in gastric cancer: a prognostic indicator in general and a predictor for lymph node metastasis in early stage cancer

BACKGROUND

Metastasis to regional lymph nodes (LNs) through lymphatic vessels is common in cancer progression and is an important prognostic factor in many cancers. Recent evidence suggests that tumour lymphangiogenesis promotes lymphatic metastasis.

AIMS

To study the role of lymph vessel density (LVD) in gastric cancer and investigate whether LVD is associated with LN metastasis/prognosis.

METHODS

Lymphatics of 117 primary human gastric cancer cases were investigated by quantitative immunohistochemical staining for podoplanin. The relation between LVD and LN metastasis and other established clinicopathological parameters was analysed. The relation between LVD and prognosis was also studied.

RESULTS

Mean LVD of "hot spots" was 11.6/case. LVD significantly correlated with LN and podoplanin positive lymphatic invasion. High LVD was associated with worse overall survival. In multivariate analysis, positive LVD was a significant independent predictor of overall survival, depth of invasion, and TNM stage. LVD significantly correlated with LN metastasis at surgery and podoplanin positive lymphatic invasion. In multivariate analysis, positive LVD was an independent significant predictor of LN metastasis.

CONCLUSIONS

Increased podoplanin expression is significantly associated with LN metastasis, and may play an important role in detecting LN metastasis in gastric cancer. Furthermore, LVD may be a significant prognostic factor in gastric cancer at any stage. In addition, LVD and lymph vessel invasion detected by podoplanin immunohistochemistry are associated with LN metastasis in T1 early gastric cancer. LVD assessment by podoplanin immunohistochemistry may become a useful predictor of LN metastasis in T1 early gastric cancer and may influence the decision making process for additional surgery.

Helicobacter bilis infection in biliary tract cancer

BACKGROUND

Biliary tract cancer is a highly fatal disease with poor prognosis, but the aetiology is poorly understood.

AIM

We aimed to identify Helicobacter bilis infection in the gallbladder in patients with biliary tract disease.

METHODS

Archival gallbladder specimens from 34 patients (14 males and 20 females) with an average age of 61.4 +/- 12.2 years (mean +/- SE) were retrieved, consisting of 11 cases of gallbladder cancer, three of bile duct cancer, 16 of cholecystolithiasis and four of pancreatic cancer. DNA was extracted and nested PCR using primers specific for 16S rRNA of H. bilis was performed.

RESULTS

Amplification was observed in 3 of 11 gallbladder cancer cases (27.2%) and one of three cases with biliary duct cancer (33.3%). In total, four of 14 cases with biliary tract cancer were positive for H. bilis (28.6%). In addition, the presence of H. bilis was shown in two of 16 cases (12.5%) with cholecystolithiasis. Notably, although the number of cases examined was small, none of the four cases with pancreatic cancer showed the presence of H. bilis infection in the gallbladder without apparent abnormalities.

CONCLUSION

H. bilis infection may play a role in biliary tract disease, particularly in biliary tract cancer.

Prognostic Factors in Breast Cancer and their Limitations

Evaluation of the prognosis of patients with breast cancer is criticai in determining post-surgical adjuvant therapy because of great heterogeneity in response to the therapy, At present, the decision-making for adjuvant therapy largely depends on histologic nodal status, but a significant number of patients without nodal involvement undergo relapse. Although great efforts have been made for more accurate and potent factors, significant indicators have not yet been found. One of the promising candidates, however, is histologic angiogenesis in tumors, which we and others have indicated as an independent prognostic factor in node-negative subset by the multivariate analysis. Here we will evaluate several prognostic factors in clinical use.

Relation between ultrasonographic and histologic findings of tracheal invasion by differentiated thyroid cancer

Between 1988 and 1999 a total of 24 patients with differentiated thyroid cancer invading the airway underwent various types of tracheal resection at the Osaka Police Hospital. Preoperative ultrasonographic (US) findings in these patients were compared with postoperative histologic results of the resected specimens to confirm the relation between the preoperative and postoperative diagnoses and to determine the indications for operative procedures. Preoperative US revealed cancer invasion to the adventitia in 2 cases, to the intercartilage space in 13, and to the tracheal mucosa in 9. Histologically, cancer invasion to the adventitia was confirmed in 4, to the intercartilage space in 10, and to the mucosa in 10. Among 13 cancer invasion instances to the intercartilage revealed by US, overdiagnosis occurred in 3 cases and underdiagnosis in 1. The actual overall diagnostic rate by US was 83.3%, which is a great improvement over other available methods. In conclusion, preoperative US findings of the trachea agreed with the histologic findings of the resected specimens, indicating US to be the first choice when making decisions about resecting the trachea and about the operative procedure.

Possible involvement of placental peptidases that degrade gonadotropin-releasing hormone (GnRH) in the dynamic pattern of placental hCG secretion via GnRH degradation

The presence of an extrahypothalamic gonadotropin releasing hormone (GnRH) in human placenta is well known and this decapeptide is presumed to play an important role in the regulation of the function and growth of human placenta. Immunohistochemistry showed that neutral endopeptidase 24.11 (NEP), a candidate of the responsible enzyme of GnRH degradation, is highly expressed on the cell surface of trophoblasts. Hydrolysis of GnRH by human villi was studied by measuring liberated amino acids using high performance liquid chromatography. The GnRH degrading activity was 1.53 times higher after incubation with the membrane fraction of first trimester villi than that after incubation with the membrane fraction of term villi. Phosphoramidon, a potent inhibitor of NEP, reduced the liberated amino acids to about a half, suggesting that NEP is a responsible enzyme for GnRH degradation. Ubenimex, which can inhibit several aminopeptidases, also reduced the liberated amino acids to about 50 per cent. O-phenanthroline, EDTA, and thiorphan could inhibit GnRH degradation but inhibitors of post proline endopeptidase could not. Furthermore, GnRH degrading activity of the membrane fraction was reduced remarkably after the membrane fraction was immunotitrated by anti NEP and anti placental leucine aminopeptidase (P-LAP) IgG. In conclusion, NEP and P-LAP are responsible enzymes for GnRH degradation in human villi.

Expression of p57/Kip2 protein in hepatocellular carcinoma

Evaluation of the biological character of carcinomas requires understanding of cell cycle regulators. In the present study, we investigated the expression of p57 (Kip2) in 90 hepatocellular carcinomas and 66 noncancerous lesions. The average p57 labeling index in noncancerous lesions was 72.3 +/- 19.7. The labeling index significantly decreased (p < 0.0001) in hepatocellular carcinoma (54.9 +/- 19.7). It was significantly lower in hepatocellular carcinoma cases with high biological aggressiveness such as advanced stage (p = 0.0041), poor differentiation (p < 0.0001), larger size (p = 0.0400), portal invasion (p < 0.0001), satellite tumor (p = 0.0023), high proliferating activity (p = 0.0002) and cyclin D(1) overexpression (p = 0.0416). Furthermore, cases with low p57 expression showed worse outcomes for disease-free survival in univariate analysis (p = 0.0235), although p57 expression could not be recognized as an independent prognostic factor. These findings suggest that p57 contributes to the downregulation of cell proliferation and to the progression of hepatocellular carcinoma.

Progesterone stimulates the expression of aminopeptidase A/angiotensinase in human choriocarcinoma cells

In human placenta aminopeptidase A (APA), a principal enzyme that converts angiotensin II to angiotensin III, seems to be involved in angiotensin II metabolism during pregnancy. In this study, we investigated the possible effects of progesterone and estrogen on APA mRNA and protein levels in choriocarcinoma cells as a model for placenta. By RNase protection assay, progesterone induced higher APA mRNA levels than estrogen at the same concentration. Progesterone exhibited dose-dependent stimulation of APA mRNA, 1.8-fold increase at 10(-6) m for 24 h treatment. Progesterone at 10(-6) m increased APA mRNA levels within 12 h and in time-dependent fashion up to 24 h. Fluorescence-activated cell sorting analysis and measurements of APA activities revealed the induction of APA protein by progesterone. Expression of progesterone receptors (PR) and glucocorticoid receptors (GR) were determined in these cells by RT-PCR, which suggested that the progesterone's actions might be displayed through PR and/or GR. These findings may serve as a useful model to study the effects of progesterone on angiotensin II metabolism in placenta, although the physiological validity of these studies remains to be clarified.

Function of nucleophosmin/B23, a nucleolar acidic protein, as a histone chaperone

We previously identified and purified a nucleolar phosphoprotein, nucleophosmin/B23, as a stimulatory factor for replication from the adenovirus chromatin. We show here that nucleophosmin/B23 functions as a histone chaperone protein such as nucleoplasmin, TAF-I, and NAP-I. Nucleophosmin/B23 was shown to bind to histones, preferentially to histone H3, to mediate formation of nucleosome, and to decondense sperm chromatin. These activities of B23 were dependent on its acidic regions as other histone chaperones, suggesting that B23/nucleophosmin is a member of histone chaperone proteins.

Expression of p57/Kip2 protein in pancreatic adenocarcinoma

INTRODUCTION

Evaluation of the biologic character of carcinomas requires understanding of cell cycle regulators.

AIMS

To investigate p57 expression in human pancreatic adenocarcinoma and cyst adenoma.

METHODOLOGY

We examined the expression of p57(Kip2), a member of the Cip/Kip family, in 45 pancreatic adenocarcinomas, 7 cystadenomas, and 7 chronic pancreatitis cases.

RESULTS

The p57 labeling index (LI) in duct epithelia in chronic pancreatitis averaged 32.8+/-8.3 and was significantly higher than in normal duct epithelia (18.8+/-6.6; p = 0.0011). For the carcinoma, the LI averaged 46.0+/-20.9, which was significantly higher than that for normal duct epithelia (p < 0.0001) and cystadenoma (16.0 11.2; p = 0.0007). However, it was significantly reduced in cases with stage IV disease (p = 0.0351), lymph node metastasis (p = 0.0003), larger size (p = 0.0094), capsular invasion (p = 0.0462), lymphatic invasion (p = 0.0351), and cell proliferating activity (p = 0.0002). In multivariate analysis, p57 LI in pancreatic adenocarcinoma was independently linked to high proliferating activity (p = 0.0230).

CONCLUSION

These results suggest that p57 plays a role in the hyperplastic change of the ducts in chronic pancreatitis and that pS7 overexpression contributes to the downregulation of cell proliferation, and its decreased expression contributes to the progression of pancreatic adenocarcinoma.

Transcriptional regulation of human placental leucine aminopeptidase/oxytocinase gene

Human placental leucine aminopeptidase (P-LAP) plays a major role in the clearance of oxytocin, which is a key hormone in regulating labour pain. To explore the transcriptional regulation of P-LAP gene expression in placenta, we performed systematic studies using human choriocarcinoma cells, BeWo and JEG-3, as a model of placental trophoblastic cells. Transient transfection and luciferase assays using various 5'-deleted P-LAP-luciferase constructs showed that the region from -297 to +49 of the transcription start site was responsible for promoter activity in these cells. Footprinting analysis with nuclear extracts from both cell lines demonstrated at least four sites for nucleoprotein interactions in this region (FP1 to FP4). Site-directed deletion of FP1-4 in luciferase assays indicated the significance of the FP3 region (-214 to -183) for high promoter activity in the cells. Electrophoretic mobility shift assays to identify the proteins interacting with DNA at FP3 revealed three retarded bands, one of which was generated by activator protein-2 (AP-2) binding. Our findings suggest that AP-2 may be one of the important factors regulating P-LAP gene expression in human placenta.

Thyroid clear cell adenoma with marked dilatation of membranous structures: electron-microscopic study

The electron-microscopic features of a thyroid follicular adenoma with clear cell change is described. The tumor was 7 mm in size and located in the upper portion of the left lobe of the thyroid of a 29-year-old Japanese female. Its cut surface was pale brown in color and well demarcated. The lesion consisted of solid nests with pinpoint lumina. The cytoplasm of the tumor cells was completely clear, but slightly vesicular without oncocytic change. Electron-microscopic examination revealed that the cytoplasm of the tumor cells was filled with numerous empty vacuoles. The vacuoles consisted of dilated membranous structures, indicating that they had been formed from rough endoplasmic reticulum and Golgi apparatus. There was no accumulation of glycogen, mucin, or lipid. The dilated membranous structures in the cytoplasm may be related to the increased thyroglobulin synthesis by the tumor.

Regulation of receptor activator of NF-kappaB ligand-induced tartrate-resistant acid phosphatase gene expression by PU.1-interacting protein/interferon regulatory factor-4. Synergism with microphthalmia transcription factor

The receptor activator of NF-kappaB ligand induces the expression of tartrate-resistant acid phosphatase (TRAP) and transcription factor, PU.1-interacting protein (Pip), during osteoclastogenesis. In this paper, we have examined the role of transcription factors in the regulation of TRAP gene expression employing reporter constructs containing the promoter region of TRAP gene. Transient transfection of RAW264 cells with sequential 5'-deletions of mouse TRAP gene promoter-luciferase fusion constructs indicated that at least two sites are required for the full promoter activity. Deletion and site-directed mutation studies revealed that M-box and interferon regulatory factor element sites are critical for TPAP gene expression in the cell, suggesting that microphthalmia transcription factor (MITF) and Pip could induce the gene expression independently. Moreover, the overexpression of MITF and Pip functionally stimulated TRAP promoter activity in a synergistic manner. Analysis of the deletion mutants of Pip protein indicated that both N-terminal DNA-binding and C-terminal regulatory domains are indispensable to the promoter-enhancing activity. Subcellular localization of green fluorescence protein-fused Pip and its mutant proteins indicated that the C-terminal domain is required for the translocation of Pip into the nucleus. These results suggest that Pip regulates and acts synergistically with MITF to induce the promoter activity of TRAP gene.

Merits and demerits of operative procedure to the trachea in patients with differentiated thyroid cancer

Local radical thyroidectomy, including cervical lymph node dissection and combined circumferential resection of the trachea, has been performed over the past 20 years in 31 patients with differentiated cancer invading the trachea. The 5- and 10-year survival rates for these patients were 77.4% and 66.7%, respectively. In 19 of the 31 (61%) cases the recurrent nerve was resected because of direct cancer invasion. Bilateral recurrent nerve palsy occurred in 12 patients, 3 of whom were managed postoperatively using a T-shaped tube for preservation of the larynx. Hoarseness remained in 21 patients. In two patients with recurrent cancer invasion of the larynx, partial laryngectomy and hemilaryngectomy were performed, and reconstruction was done using ear cartilage without postoperative dyspnea or dysphagia. Parathyroid function is an important factor in regard to the quality of life of patients. In 22 patients at least one of the parathyroids was preserved. Postoperative calcium administration was necessary in 14 patients. Our long-term observations indicate that local radical thyroidectomy with combined resection of the trachea can serve as a useful treatment for advanced differentiated cancer invading the airway.

Identification of nucleophosmin/B23, an acidic nucleolar protein, as a stimulatory factor for in vitro replication of adenovirus DNA complexed with viral basic core proteins

The processes governing chromatin remodeling and assembly, which occur prior to and/or after transcription and replication, are not completely understood. To understand the mechanisms of transcription and replication from chromatin templates, we have established in vitro replication and transcription systems using adenovirus (Ad) DNA complexed with viral basic core proteins, called Ad core, as a template. Using this system, we have previously identified, from HeLa cells, template activating factor-I as a stimulatory factor for the Ad core DNA replication. Here, using this system as a tool, we identified and purified a novel template activating factor activity that consists of two acidic polypeptides whose apparent molecular masses are 38 kDa and 37 kDa. These two polypeptides correspond to two splicing variants of nucleolar phosphoprotein, nucleophosmin/B23. Recombinant B23 proteins stimulate the Ad core DNA replication, and the acidic regions of B23 proteins are important for its activity. In addition, B23 proteins directly bind to core histones and transfer them to naked DNA. Furthermore, chromatin components such as histones and topoisomerase II are co-immunoprecipitated with B23 from cell extracts. These observations lead to a hypothesis that nucleophosmin/B23 is involved in structural changes of chromatin, thereby regulating transcription and replication within the ribosomal DNA region or maintaining the nucleolar structure.

Further evidence for the involvement of insulin receptor substrates in epidermal growth factor-induced activation of phosphatidylinositol 3-kinase

In accordance with our recent results obtained with cultured rat hepatocytes [Fujioka, T. & Ui, M. (2001) Eur. J. Biochem. 268, 25-34], epidermal growth factor (EGF) gave rise to transient tyrosine phosphorylation of insulin receptor substrates (IRS-1 and IRS-2), thereby activating the bound phosphatidylinositol 3-kinase in human epidermoid carcinoma A431 cells normally abundant in EGF receptors (EGFR) and Chinese hamster ovary (CHO) cells transfected with full-length EGFR. These actions of EGF, although much smaller in magnitude than those of insulin or IGF-I in the same cells, were accompanied by tyrosine phosphorylation of EGFR rather than insulin or IGF-I receptors, never observed in wild-type CHO cells expressing no EGFR, and totally inhibited by an inhibitor of EGFR kinase, AG1478, that was without effect on insulin or IGF-I actions. Recombinant IRS-1 was phosphorylated on tyrosines upon incubation with purified EGFR from A431 cells and 32P-labeled ATP. When CHO cells were transfected with C-terminal truncated EGFR lacking three NPXY motifs responsible for direct binding to phosphotyrosine-binding domains of IRSs, no effect of EGF could be observed. We suggest that tyrosine phosphorylation of IRS-1 or IRS-2 could mediate EGFR-induced activation of phosphatidylinositol 3-kinase in mammalian cells.

Genomic organization of the human adipocyte-derived leucine aminopeptidase gene and its relationship to the placental leucine aminopeptidase/oxytocinase gene

The genomic organization of the gene encoding the human adipocyte-derived leucine aminopeptidase (A-LAP) has been determined. The gene is composed of 20 exons and 19 introns and spans approximately 47 kilobases of chromosome 5q15. The gluzincin aminopeptidase motif, the HEXXH(X)(18)E zinc-binding motif essential for enzymatic activity, is encoded by exons 6 and 7. A comparison of the exon/intron boundaries, together with phylogenetic analysis, shows the close relationship between A-LAP and placental leucine aminopeptidase (P-LAP)/oxytocinase, another gluzincin aminopeptidase considered to be important for the maintenance of normal pregnancy. Primer extension analysis revealed two transcriptional initiation sites. Analysis of the sequence immediately upstream of the transcriptional initiation sites revealed that the A-LAP promoter contains no canonical TATA- or CCAAT-box, but has a PyPyA(+1)N(T/A)PyPy initiator consensus sequence and multiple putative regulatory elements. Finally, luciferase-reporter assays revealed a functional promoter activity of the 5'-flanking region of the gene, and suggested that the activity is regulated in a cell type-specific manner.

Primary pancreatic lymphoma: clinicopathological analysis of 19 cases from Japan and review of the literature

Primary pancreatic lymphoma (PL) is an extremely rare disease, and large-scale studies are rarely performed even in Western countries, in which all cases of PL reported to date were of the B-cell type. Little information regarding PL is available in Japan. Nineteen cases of PL were collected through a nationwide study in Japan, and paraffin-embedded specimens were processed for staining with hematoxylin and eosin and by immunohistochemical procedures. Clinicopathological findings were reviewed and compared with those reported in Western countries. The patient population consisted of 13 men and 6 women, ranging in age from 46 to 84 (average 62) years. Abdominal pain was the most common presenting symptom. Tumors were located in the pancreatic head (12 cases), tail (4 cases) and body (2 cases), and ranged in size from 4 to 17 cm. Clinical stage was I(E) in 9 cases and II(E) in 10. Radical resection was performed in 10 cases and bypass operation in 1, followed by chemotherapy in 8. Immunophenotypically, 15 cases were B-cell and 4 were T-cell lymphomas. Seventy-three percent of B-cell tumors were diffuse large B-cell lymphomas. The 1-year actuarial survival rate for B-cell lymphomas (51.9%) was better than that of T-cell lymphomas (0%). However, in Japan the incidence of T-cell PLs was higher, and, partly as a consequence of this, prognosis was poorer than in Western countries.

Expression of p73 and p63 proteins in pancreatic adenocarcinoma: p73 overexpression is inversely correlated with biological aggressiveness

The significance of p53, a prominent tumor suppressor gene, and its product in various neoplasms including pancreatic adenocarcinoma has been established. We investigated the expression of two types of homologue of p53, p73 and p63, in pancreatic adenocarcinoma by means of immunohistochemistry. Overexpression of p73 was observed in 45.6% of the cases and this phenomenon was more frequently seen in cystic adenocarcinomas than in ductal carcinomas. Furthermore, p73 overexpression was inversely linked to lymph node metastasis, tumor size, and Ki-67 labeling index. On the other hand, p63 overexpression was observed in 68.2% of the cases, but was not related to any clinicopathological features. No correlation was established between the expression of these proteins and aberrant p53 expression. These results suggest that decreased expression of p73 protein and over-expression of p63 protein may play a role in the development of pancreatic adenocarcinoma.

Activation of c-Src gene product in hepatocellular carcinoma is highly correlated with the indices of early stage phenotype

BACKGROUND/AIMS

The aim of this study was to investigate whether c-Src is involved in carcinogenesis and progression of human hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma.

METHODS

We designed an immunohistochemical study using Clone 28, an antibody that specifically recognizes the activated form of c-Src.

RESULTS

Hepatocytes in normal liver, chronic hepatitis with or without cirrhosis, atypical adenomatous hyperplasia, as well as bile ductular cells, and infiltrating mononuclear cells were all negative for immunohistochemical staining for the activated c-Src. Among 87 cases of HCC tested, 40 (46%) were positively stained for the activated c-Src, and this positive staining was inversely correlated with the Ki-67 labeling index (LI) (P = 0.0031), intrahepatic metastasis (P = 0.0099), TNM stage (P = 0.0062), alpha-fetoprotein (P = 0.0103) and epidermal growth factor-receptor expression (P = 0.0153). Positive staining for the activated c-Src was more frequently observed in well- or moderately-differentiated carcinoma (P = 0.0256). In multivariate analysis, the activated c-Src expression was independently related to the Ki-67 LI (P = 0.0197). In contrast to positive staining in HCC, cholangiocarcinoma were classified as negative in all 19 cases examined.

CONCLUSIONS

These results strongly suggest the involvement of activated c-Src in early stages of HCC, and suggest that cholangiocarcinoma might employ different signaling mechanisms.

Expression of heparin binding epidermal growth factor-like growth factor in hepatocellular carcinoma: an immunohistochemical study

Previous studies have demonstrated an elevated level of heparin-binding epidermal growth factor-like growth factor (HB-EGF) mRNA in hepatocarcinogenesis in a rodent model and of its protein as well as mRNA in human hepatocellular carcinoma (HCC). In order to elucidate the clinical significance of HB-EGF in human HCC, we immunohistochemically investigated its expression in 100 HCC cases with different characteristics. HB-EGF was not or only faintly expressed in non-cancerous hepatocytes. On the other hand, 59% of the HCC cases were classified as positive for HB-EGF, and its expression was more frequently observed in cases with low proliferating activity, at an early stage, of small size, without portal invasion, low alpha-fetoprotein level, without satellite nodules (borderline significance), and well or moderate differentiation. Furthermore, HB-EGF expression showed prognostic significance in both univariate and multivariate analyses and can be regarded as an independent prognostic factor of disease-free survival. These results strongly suggest the involvement of HB-EGF in early stage of HCC.

Expression and clinical significance of erb-B receptor family in hepatocellular carcinoma

In order to elucidate the clinical significance of the erbB family, epidermal growth factor receptor (EGF-R), c-erbB-2, c-erbB-3 and c-erbB-4 in hepatocellular carcinoma (HCC), we investigated the expression of these proteins by means of immunohistochemistry for HCC as well as adjacent noncancerous lesions. EGF-R was expressed in 68% of the HCC examined and showed correlation with the proliferating activity, stage, intrahepatic metastasis and carcinoma differentiation. c-erbB-2 was expressed in only 21% of the cases and showed no relationships with the clinicopathological parameters. c-erbB-3 protein was observed in 84% of the HCC and 38.1% of the noncancerous lesions. Its expression in HCC was equal to or greater than noncancerous lesions in 90.5% of the cases, and was related to the stage, portal invasion, cell proliferating activity, tumour size, intrahepatic metastasis and carcinoma differentiation. c-erbB-4 protein was expressed in 61.0% of HCC and in as much as 86.1% of the noncancerous lesions. Unlike the expression of c-erbB-3, that of c-erbB-4 in HCC was less than that of the adjacent noncancerous lesions in 51.2% of the cases. No statistical significance could be established between this protein expression in HCC and clinicopathological features. EGF-R and c-erbB-3 affected disease-free survival, but were not recognized as independent prognostic factors by multivariate analysis. The present study suggests that, of the four receptors, EGF-R and c-erbB-3 play important roles in the progression of HCC. © 2001 Cancer Research Campaign www.bjcancer.com

Expression and clinical significance of the erbB family in intrahepatic cholangiocellular carcinoma

The type I family of growth factor receptors is known to play a role in the development of several carcinomas, but its role in hepatic malignancies is not clearly understood. In this study we investigated the expression of this family of EGF-R, c-erbB-2, c-erbB-3 and c-erbB-4 in 38 intrahepatic cholangiocellular carcinomas (CCC) by means of immunohistochemistry. EGF-R expression was related to lymph node metastasis, aberrant p53 expression, proliferating activity, and carcinoma differentiation. c-erbB-2 expression was observed in more than 50% of the cases, but was not related to any clinicopathological features, c-erbB-3 expression was linked to lymph node metastasis, and c-erbB-4 expression was directly related to proliferating activity and lymph node metastasis. These results indicate that: 1) EGF-R contributes greatly to CCC progression, and c-erbB-3 and c-erbB-4 have roles similar to but less than that of EGFR, and 2) c-erbB-2 is expressed in CCC in high incidence, but its clinical role in CCC remains unclear.