Parallel propagating electromagnetic waves in magnetized quantum electron plasmas with finite temperature

We studied parallel propagating electromagnetic waves in a magnetized quantum electron plasma of finite temperature, as an extension of our previous study on a zero temperature plasma. We obtained simple analytic dispersion relations in the long wavelength limit that included the thermal effect as correction terms to the zero temperature results. As in the zero temperature case, the lower branch of the R wave showed significant damping and became ill-defined at short wavelengths. Quantum effects seemed to give qualitative changes, such as the appearance of anomalous dispersion regions, to the classical dispersion relations when v_{F}/v_{th}≤0.2 for a set of exemplary parameters of v_{F}=0.1c and ω_{ce}/ω_{pe}=0.05 was used. We also noted that introduction of the Planck constant in the quantum Vlasov equation changed the shape of the anomalous dispersion region qualitatively, by forming a normal dispersion region in the middle of the original single broad anomalous dispersion region.

Open-label randomized non-inferiority trial of a fixed-dose combination of glimepiride and atorvastatin for the treatment of people whose Type 2 diabetes is uncontrolled on metformin

AIMS

To evaluate, in a randomized, open-label study, the non-inferiority of a bioequivalent fixed-dose combination of glimepiride and atorvastatin vs. separately co-administered tablets in people with Type 2 diabetes mellitus.

METHODS

Participants with HbA1c ≥ 53 to < 80 mmol/mol (≥ 7.0 to < 9.5%), average fasting blood glucose > 7.0 mmol/l, who were on metformin for ≥ 3 months, were randomized to combination (n = 215) or co-administered glimepiride and atorvastatin (n = 212) once daily for 20 weeks. Up-titration of glimepiride (1-4 mg) and atorvastatin (10-20 mg) were based on average fasting blood glucose and LDL cholesterol, respectively. Co-primary endpoints were change from baseline to week 20 in HbA1c and LDL cholesterol.

RESULTS

Non-inferiority was demonstrated for both co-primary endpoints: the upper limits of 95% CIs for differences (combination-reference) were less than the prespecified margins of 3.3 mmol/mol (0.3%) for change from baseline in HbA1c [difference 0.1 mmol/mol (95% CI -1.6, 1.9); 0.01% (95% CI -0.15, 0.17)] and 6% for percentage change from baseline in LDL cholesterol [difference 0.87% (95% CI -2.47, 4.21)]. Similar proportions of participants on combination and reference had treatment-emergent adverse events (64 vs. 61%). More participants on combination had hypoglycaemia (21 vs. 13%); most events were considered by the treating physician to be unrelated to study drug.

CONCLUSIONS

The combination was non-inferior to separately co-administered tablets and the safety profile was consistent with the known profiles of glimepiride and atorvastatin. The observed increase in hypoglycaemia on the combination cannot be explained, but may be attributable to non-systematic collectiof glucose readings and may have been influenced by reporting bias in this open-label trial.

Lobeglitazone and pioglitazone as add-ons to metformin for patients with type 2 diabetes: a 24-week, multicentre, randomized, double-blind, parallel-group, active-controlled, phase III clinical trial with a 28-week extension

We aimed to compare the efficacy and safety of lobeglitazone and pioglitazone as add-ons to metformin in patients with type 2 diabetes. Patients who were inadequately controlled by metformin were randomized and treated once daily with either lobeglitazone (0.5 mg, n = 128) or pioglitazone (15 mg, n = 125) for 24 weeks, with a 28-week extension trial of lobeglitazone treatment in patients who consented. The primary endpoint was the change in glycated haemoglobin (HbA1c) concentration from baseline to week 24. At week 24, the mean change from baseline in HbA1c was -0.74% for the lobeglitazone group and -0.74% for the pioglitazone group, with a mean difference of 0.01% [95% confidence interval (CI) of difference, -0.16 to 0.18]. The effects of lobeglitazone on lipid variables and the adverse events associated with lobeglitazone were similar to those observed with pioglitazone. Lobeglitazone was not inferior to pioglitazone as an add-on to metformin in terms of their efficacy and safety.

Anagliptin and sitagliptin as add-ons to metformin for patients with type 2 diabetes: a 24-week, multicentre, randomized, double-blind, active-controlled, phase III clinical trial with a 28-week extension

We conducted a 24-week, multicentre, double-blind, randomized study with a 28-week extension to compare the efficacy and safety of anagliptin and sitagliptin as an add-on to metformin in patients with type 2 diabetes. Patients inadequately controlled on metformin were randomized to either anagliptin (100 mg twice daily, n = 92) or sitagliptin (100 mg once daily, n = 88). The primary endpoint was the change in glycated haemoglobin (HbA1c) from baseline to week 24. The mean changes in HbA1c were -0.85 ± 0.70% (p < 0.0001) for anagliptin and -0.83 ± 0.61% (p < 0.0001) for sitagliptin, with a mean difference of -0.02% (95% confidence interval of difference, -0.22 to 0.18%). In both groups, the fasting proinsulin : insulin ratio significantly decreased from baseline, with improved insulin secretion. Safety profiles were similar in each group. In conclusion, the non-inferiority of the efficacy of anagliptin to sitagliptin as an add-on therapy was established with regard to efficacy and safety.

NAG-1/GDF15 accumulates in the nucleus and modulates transcriptional regulation of the Smad pathway

Protein dynamics, modifications, and trafficking are all processes that can modulate protein activity. Accumulating evidence strongly suggests that many proteins play distinctive roles dependent on cellular location. Nonsteroidal anti-inflammatory drug activated gene-1 (NAG-1) is a TGF-β superfamily protein that plays a role in cancer, obesity, and inflammation. NAG-1 is synthesized and cleaved into a mature peptide, which is ultimately secreted into the extracellular matrix (ECM). In this study, we have found that full-length NAG-1 is expressed in not only the cytoplasm and ECM, but also in the nucleus. NAG-1 is dynamically moved to the nucleus, exported into cytoplasm, and further transported into the ECM. We have also found that nuclear NAG-1 contributes to inhibition of the Smad pathway by interrupting the Smad complex. Overall, our study indicates that NAG-1 is localized in the nucleus and provides new evidence that NAG-1 controls transcriptional regulation in the Smad pathway.

Efficacy and safety of the dipeptidyl peptidase-4 inhibitor gemigliptin compared with sitagliptin added to ongoing metformin therapy in patients with type 2 diabetes inadequately controlled with metformin alone

AIMS

This study was designed to assess the efficacy and safety of a dipeptidyl peptidase-4 inhibitor, gemigliptin versus sitagliptin added to metformin in patients with type 2 diabetes.

METHODS

We conducted a double-blind, randomized, active-controlled trial in 425 Asian patients with inadequately controlled type 2 diabetes being treated with metformin alone. Eligible patients were randomized into three groups: 50 mg gemigliptin qd, 25 mg gemigliptin bid or sitagliptin 100 mg qd added to ongoing metformin treatment for 24 weeks. Haemoglobin A1c (HbA1c) and fasting plasma glucose (FPG) were measured periodically, and oral glucose tolerance tests were performed at baseline and 24 weeks after starting the treatment regimen.

RESULTS

Twenty-four weeks later, adding gemigliptin (50 mg/day) to ongoing metformin therapy significantly improved glycaemic control. Reduction in HbA1c caused by 50 mg gemigliptin qd (-0.77% ± 0.8) was non-inferior to that caused by 100 mg sitagliptin qd (-0.8% ± 0.85). Proportion of patients achieving HbA1c <7% while taking 25 mg gemigliptin bid (50%) or 50 mg gemigliptin qd (54.07%) was comparable to the results with 100 mg sitagliptin qd (48.87%). There were significant decreases in FPG, postprandial glucose and AUC0-2 h glucose, as well as increases in GLP-1 and β cell sensitivity to glucose (supported by homeostasis model assessment of β-cell function, postprandial 2-h c-peptide and insulinogenic index) in patients receiving gemigliptin treatment with their metformin therapy. There was no increased risk of adverse effects with this dose of gemigliptin compared with sitagliptin 100 mg qd.

CONCLUSIONS

Addition of gemigliptin 50 mg daily to metformin was shown to be efficacious, well tolerated and non-inferior to sitagliptin in patients with type 2 diabetes mellitus.

A multicentre, multinational, randomized, placebo-controlled, double-blind, phase 3 trial to evaluate the efficacy and safety of gemigliptin (LC15-0444) in patients with type 2 diabetes

AIM

This study was designed to assess the efficacy and safety of the dipeptidyl peptidase IV inhibitor gemigliptin (LC15-0444) 50 mg versus placebo in patients with type 2 diabetes.

METHODS

We conducted a 24-week, randomized, double-blind, placebo-controlled phase III trial in 182 patients (74 from Korea and 108 from India) with type 2 diabetes. After an initial 2 weeks of a diet and exercise programme followed by 2 weeks of a single-blind placebo run-in period, eligible patients were randomized to gemigliptin 50 mg or placebo, receiving the assigned treatment for 24 weeks. HbA1c and fasting plasma glucose (FPG) were measured periodically, and oral glucose tolerance test was performed at baseline and weeks 12 and 24.

RESULTS

At week 24, gemigliptin treatment led to significant reductions in HbA1c measurements compared to placebo (adjust mean after subtracting the placebo effect size: -0.71%, 95% confidence interval: -1.04 to -0.37%). A significantly greater proportion of patients achieved an HbA1c <7% with gemigliptin than with placebo. The placebo-subtracted FPG change from baseline at week 24 was -19.80 mg/dl. The overall incidence rates for adverse events were similar in the gemigliptin and placebo groups.

CONCLUSIONS

This study showed the efficacy and safety of gemigliptin 50 mg administered once daily as a monotherapy for type 2 diabetes patients.

Efficacy and safety of glimepiride/metformin sustained release once daily vs. glimepiride/metformin twice daily in patients with type 2 diabetes

AIMS

The study investigated the clinical equivalence in reducing haemoglobin A1c (A1C) between glimepiride/metformin sustained release (GM-SR) 2/500 mg, a fixed-dose combination, once daily and glimepiride/metformin (GM) 1/250 mg, a fixed-dose combination, twice daily in patients with type 2 diabetes (T2D).

METHODS

A multicentre, randomised, double-blind, double-dummy study was conducted in 14 hospitals in Korea. Inclusion criteria were age 30-75 years, T2D diagnosis no longer than 10 years previously, A1C between 7% and 10%, and body mass index <40 kg/m(2) . A total of 207 subjects were randomised into the GM-SR group (n=101) or the GM group (n=106). Participants were assessed at baseline, 8 weeks and 16 weeks after treatment.

RESULTS

After 16 weeks treatment, no difference in baseline-adjusted changes of A1C (primary efficacy variable) was observed between the two groups (-0.59% for GM-SR group vs. -0.61% for GM group, 95% CI: -0.17 to 0.21; p=0.84). In addition, there were no significant differences in secondary efficacy parameters between the two groups, including changes in A1C up to week 8, changes in fasting plasma glucose (FPG) and 2-h-postprandial plasma glucose up to week 8 and week 16, response rate, drug compliance and hypoglycaemic events. However, there was a difference in baseline-adjusted changes of FPG between the two groups (-1.01 mmol/l for GM-SR group vs. -1.52 mmol/l for GM group, p=0.01 in the intention to treat set).

CONCLUSIONS

GM-SR 2/500 mg once daily was as effective as GM 1/250 mg twice daily in lowering A1C. In addition, no difference was noted in hypoglycaemic events between the two groups.

Slewing Mirror Telescope optics for the early observation of UV/optical photons from Gamma-Ray Bursts

We report on design, manufacture, and testing of a Slewing Mirror Telescope (SMT), the first of its kind and a part of Ultra-Fast Flash Observatory-pathfinder (UFFO-p) for space-based prompt measurement of early UV/optical light curves from Gamma-Ray Bursts (GRBs). Using a fast slewing mirror of 150 mm diameter mounted on a 2 axis gimbal stage, SMT can deliver the images of GRB optical counterparts to the intensified CCD detector within 1.5~1.8 s over ± 35 degrees in the slewing field of view. Its Ritchey-Chrétien telescope of 100 mm diameter provides a 17 × 17 arcmin² instantaneous field of view. Technical details of design, construction, the laboratory performance tests in space environments for this unique SMT are described in conjunction with the plan for in-orbit operation onboard the Lomonosov satellite in 2013.

Randomized, double-blind, placebo-controlled trial of the once-daily GLP-1 receptor agonist lixisenatide in Asian patients with type 2 diabetes insufficiently controlled on basal insulin with or without a sulfonylurea (GetGoal-L-Asia)

AIMS

To assess the efficacy and safety of once-daily lixisenatide versus placebo in Asian patients with type 2 diabetes insufficiently controlled on basal insulin ± sulfonylurea.

METHODS

In this 24-week, randomized, double-blind, placebo-controlled, parallel-group, multicentre study, participants (mean baseline HbA(1c) 8.53%) from Japan, Republic of Korea, Taiwan and the Philippines received lixisenatide (n = 154) or placebo (n = 157) in a stepwise dose increase to 20 µg once daily. The primary endpoint was HbA(1c) change from baseline to week 24.

RESULTS

Once-daily lixisenatide significantly improved HbA(1c) versus placebo (LS mean difference vs. placebo = -0.88% [95%CI= -1.116, -0.650]; p < 0.0001), and allowed more patients to achieve HbA(1c) <7.0% (35.6 vs. 5.2%) and ≤ 6.5% (17.8 vs. 1.3%). Lixisenatide also significantly improved 2-h postprandial plasma glucose and glucose excursion, average 7-point self-monitored blood glucose and fasting plasma glucose. Lixisenatide was well tolerated; 86% of patients on lixisenatide completed the study versus 92% on placebo. Ten (6.5%) lixisenatide and 9 (5.7%) placebo patients experienced serious adverse events. More lixisenatide patients [14 (9.1%)] discontinued for adverse events versus placebo [5 (3.2%)], mainly with gastrointestinal causes. Nausea and vomiting were reported in 39.6 and 18.2% of patients on lixisenatide versus 4.5 and 1.9% on placebo. Symptomatic hypoglycaemia was more frequent with lixisenatide (42.9%) versus placebo (23.6%), but was similar between groups (32.6 vs. 28.3%, respectively), in those not receiving sulfonylureas. No severe hypoglycaemia was reported.

CONCLUSIONS

In an Asian type 2 diabetes population insufficiently controlled by basal insulin  ±  sulfonylurea, once-daily lixisenatide significantly improved glycaemic control, with a pronounced postprandial effect, and was well tolerated.

Randomized, double-blind, placebo-controlled trial of the once-daily GLP-1 receptor agonist lixisenatide in Asian patients with type 2 diabetes insufficiently controlled on basal insulin with or without a sulfonylurea (GetGoal-L-Asia)

AIMS

To assess the efficacy and safety of once-daily lixisenatide versus placebo in Asian patients with type 2 diabetes insufficiently controlled on basal insulin ± sulfonylurea.

METHODS

In this 24-week, randomized, double-blind, placebo-controlled, parallel-group, multicentre study, participants (mean baseline HbA(1c) 8.53%) from Japan, Republic of Korea, Taiwan and the Philippines received lixisenatide (n = 154) or placebo (n = 157) in a stepwise dose increase to 20 µg once daily. The primary endpoint was HbA(1c) change from baseline to week 24.

RESULTS

Once-daily lixisenatide significantly improved HbA(1c) versus placebo (LS mean difference vs. placebo = -0.88% [95%CI= -1.116, -0.650]; p < 0.0001), and allowed more patients to achieve HbA(1c) <7.0% (35.6 vs. 5.2%) and ≤ 6.5% (17.8 vs. 1.3%). Lixisenatide also significantly improved 2-h postprandial plasma glucose and glucose excursion, average 7-point self-monitored blood glucose and fasting plasma glucose. Lixisenatide was well tolerated; 86% of patients on lixisenatide completed the study versus 92% on placebo. Ten (6.5%) lixisenatide and 9 (5.7%) placebo patients experienced serious adverse events. More lixisenatide patients [14 (9.1%)] discontinued for adverse events versus placebo [5 (3.2%)], mainly with gastrointestinal causes. Nausea and vomiting were reported in 39.6 and 18.2% of patients on lixisenatide versus 4.5 and 1.9% on placebo. Symptomatic hypoglycaemia was more frequent with lixisenatide (42.9%) versus placebo (23.6%), but was similar between groups (32.6 vs. 28.3%, respectively), in those not receiving sulfonylureas. No severe hypoglycaemia was reported.

CONCLUSIONS

In an Asian type 2 diabetes population insufficiently controlled by basal insulin  ±  sulfonylurea, once-daily lixisenatide significantly improved glycaemic control, with a pronounced postprandial effect, and was well tolerated.

A multicenter, randomized, placebo-controlled, double-blind phase II trial evaluating the optimal dose, efficacy and safety of LC 15-0444 in patients with type 2 diabetes

AIM

The objective of this study was to evaluate the optimal dose, efficacy and safety of a novel dipeptidyl peptidase-4 (DPP-IV) inhibitor, LC15-0444, in Korean subjects with type 2 diabetes mellitus treated by diet and exercise.

METHODS

This study was a double-blind, randomized, multicenter and parallel-group, dose-range finding study. We enrolled 145 patients (91 men and 54 women) with a median age of 53 years and a median body mass index of 25.1 kg/m(2) . The median baseline fasting plasma glucose (FPG) was 8.1 mmol/l, the median HbA1c was 7.9% and the median time since the diagnosis of diabetes was 3 years. After 2 weeks of an exercise/diet programme followed by 2 weeks of a placebo period, the subjects were randomized to one of the four following groups for a 12-week active treatment period: placebo and 50, 100 or 200 mg of LC15-0444.

RESULTS

All three doses of LC15-0444 significantly reduced the HbA1c from baseline compared to the placebo group (-0.06 vs. -0.98, -0.74 and -0.78% in the placebo and 50, 100 and 200 mg groups, respectively), without a significant difference between the doses. Subjects with a higher baseline HbA1c (≥8.5%) had a greater reduction in HbA1c. Insulin secretory function, as assessed using homeostasis model assessment-beta cell, C-peptide and the insulinogenic index, improved significantly with LC15-0444 treatment. Insulin sensitivity, as assessed using homeostasis model assessment-insulin resistance, also improved significantly after 12 weeks of treatment. The 50 and 200 mg groups had significantly reduced total cholesterol and low-density lipoprotein cholesterol levels at 12 weeks compared to the placebo group. No dosage of LC15-0444 affected weight or waist circumference. The incidences of adverse events were similar in all study subjects.

CONCLUSIONS

LC15-0444 monotherapy (50 mg for 12 weeks) improved the HbA1c, FPG level, oral glucose tolerance test results, β-cell function and insulin sensitivity measures, and was well tolerated in Korean subjects with type 2 diabetes.

The effects of total energy expenditure from all levels of physical activity vs. physical activity energy expenditure from moderate-to-vigorous activity on visceral fat and insulin sensitivity in obese Type 2 diabetic women

AIMS

We examined the effects of physical activity with or without dietary restriction for 3 months on regional fat and insulin sensitivity and compared the effect of total energy expenditure from all levels of physical activity with that of physical activity energy expenditure from moderate-to-vigorous exercise in obese women with Type 2 diabetes.

METHODS

In this randomized, controlled trial, we assessed change of body weight, abdominal visceral fat area, subcutaneous fat area and insulin sensitivity, expressed as K(ITT), and monitored total energy expenditure and physical activity energy expenditure using an accelerometer during a 12-week intervention in four groups: control, diet, exercise and diet plus exercise.

RESULTS

The mean body mass index was 28.0 +/- 2.7 kg/m(2) and the mean duration of diabetes was 8 +/- 6 years. Both the diet and diet plus exercise groups showed significant body weight loss compared with the control group (P < 0.05). However, the visceral fat area was reduced only in the diet and exercise group (P = 0.017) and the subcutaneous fat area was reduced only in the diet group (P = 0.009). Mean energy intake was an independent determinant of the change in subcutaneous fat area (P = 0.020) and mean total anergy expenditure was an independent determinant of visceral fat area (P = 0.002). Insulin sensitivity K(ITT) was associated with physical activity energy expenditure (P = 0.006), energy intake (P = 0.047) and the change in fructosamine level (P = 0.016) but not with changes in body weight, subcutaneous fat area, visceral fat area or adipokine level.

CONCLUSIONS

Exercise had an additive effect to dietary restriction on visceral fat reduction. Visceral fat area was associated with total energy expenditure, but insulin sensitivity was associated with physical activity energy expenditure.

Valsartan increases circulating adiponectin levels without changing HOMA-IR in patients with type 2 diabetes mellitus and hypertension

Evaluating increasing circulating adiponectin levels is becoming an important strategy in the prevention of diabetes mellitus and cardiovascular events. This study was designed to investigate the effect of the angiotensin II receptor blocker valsartan on blood adiponectin levels and insulin sensitivity in patients with type 2 diabetes and mild-to-moderate hypertension. A total of 91 Korean patients were treated with 80 mg/day valsartan for 4 weeks followed by 160 mg/day for a further 8 weeks. Blood pressure, adiponectin levels and metabolic parameters were measured before and after treatment. The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated as an insulin sensitivity index. Valsartan significantly decreased mean blood pressure and increased circulating adiponectin levels. There were no differences in metabolic parameters, including HOMA-IR, glycosylated haemoglobin and lipid levels before and after treatment. These results indicated that valsartan increases circulating adiponectin levels, but does not change insulin sensitivity in patients with type 2 diabetes and mild-to-moderate hypertension.

Resistance Exercise Did Not Alter Intramuscular Adipose Tissue but Reduced Retinol-binding Protein-4 Concentration in Individuals with Type 2 Diabetes Mellitus

Lipid accumulation in muscle is associated with diminished insulin sensitivity. It was hypothesized that resistance exercise decreases muscular adipose tissue and reduces the level of retinol-binding protein-4 (RBP4), which is linked to adipose tissue and insulin sensitivity in diabetics. Forty-four women with type 2 diabetes were randomly assigned to three groups for a period of 12 weeks: control (asked to maintain a sedentary lifestyle); resistance exercise (elastic band exercise at moderate intensity five times per week); and aerobic exercise (walking for 60 min at moderate intensity five times per week). Subcutaneous (SCAT), subfascial (SFAT) and intramuscular (IMAT) adipose tissues at mid-thigh level were assessed using computed tomography, and RBP4 level and insulin sensitivity (fractional disappearance rate of insulin, kITT) were assessed before and after intervention. Changes in SCAT, SFAT, IMAT, RBP4 and kITT were similar among the three groups. Within-group analysis revealed that body mass index and waist circumference decreased significantly in both exercise groups, but RBP4 decreased significantly only with resistance exercise. Resistance exercise did not alter muscular adipose tissue or improve insulin sensitivity.

Transferring type 2 diabetes patients with uncontrolled glycaemia from biphasic human insulin to biphasic insulin aspart 30: experiences from the PRESENT study

AIM

The Physician's Routine Evaluation of Safety and Efficacy of NovoMix* 30 Therapy (PRESENT) aims to assess the safety and efficacy of biphasic insulin aspart (BIAsp30) used in routine clinical practice.

METHODS

This was a large, multi-national, multi-centre, prospective, 6-month study in type 2 diabetes mellitus patients who were prescribed BIAsp30. Efficacy endpoints included changes in HbA(1c), fasting plasma glucose (FPG), postprandial plasma glucose (PPPG), and proportion who achieved target HbA(1c) < 7%. Changes from baseline were analysed using paired t-test. Safety endpoints were incidence and rate of hypoglycaemic episodes. A subgroup of patients previously uncontrolled (HbA(1c) > or = 7.0%) on biphasic human insulin (BHI) were analysed.

RESULTS

Glycaemia improved significantly (mean +/- SD): HbA(1c) by 1.58 +/- 1.69% points (from 9.32 +/- 1.64% to 7.70 +/- 1.29%), FPG by 2.92 +/- 3.71 mmol/L and PPPG by 4.75 +/- 4.87 mmol/L. The incidence of hypoglycaemic episodes decreased over time, from 38.7% (baseline) to 20.8% (6 months). Episodes were mostly minor (reduced from 37.7 to 20.6% at 6 months), occurring during the day (reduced from 31.5 to 17.1% at 6 months). Major episodes were less frequently reported (reduced from 5.0 to 0.4% at 6 months). The rate of hypoglycaemia (episodes/patient year) from baseline to end of study decreased over time for overall (8.9-2.2), major (0.7-0.1), minor (8.2-2.2) and nocturnal (2.9-0.5) episodes.

CONCLUSIONS

In this observational study, in the type 2 diabetes mellitus patients who were poorly controlled on BHI, glycaemia improved when transferred to BIAsp30, and a lower incidence or rate of hypoglycaemia was observed in these patients.

Interstitial cells of Cajal (ICC) and gastrointestinal stromal tumor (GIST): facts, speculations, and myths

Interstitial cells of Cajal (ICC) is a peculiar cell network composed of cells having processes described by the eminent Spanish neuroanatomist of the 19th century, S. Ramon y Cajal. ICC became a fascinating subject to many investigators and it is estimated that there are over 100 publications yearly on the subject related to ICC, in the last three years. Now it is widely accepted that ICC are pace maker cells of the gut and probable progenitor cells of gastrointestinal stromal tumors (GIST). Lately, interstitial Cajal-like cells (ICLC) are being found in various organs and their physiological role is still to be defined. We have reviewed the literature trying to evaluate the validity of the current concept and found that there are a few salient points to be considered. 1) There has been some important departure in defining the identity of ICC from the original criteria of Cajal. In particular, ICC with myoid feafures in intestinal smooth muscle layers (ICC-DPM) do not seem to fit to the original description of interstitial cell network by Cajal. We have also pointed out that the current reports assigning a pace maker role to ICC vastly depend on the scientific data on "ICC with myoid features", not on "fibroblast-like ICC", which are more abundant and easier to identify. 2) There seem to be an overwhelming amount of data proving the relationship between ICC and GIST. Both are known to express c-Kit and the ultrastructural characteristics seen in GIST roughly parallel those of ICC including minimal myoid differentiation seen in the majority of GIST, supporting the current concept that GIST are ICC tumors. 3) According to the original description of Cajal, ICC was not limited to the gut, suggesting an existence of ICC in other organs. The list of organs reported to contain ICC (currently identified by immunohistochemistry and electron microscopy) is ever growing and further studies are needed to define their identity and pathophysiologic role. 4). Recent data concerning gut development suggest that both c-Kit expressing ICC (fibroblasts-like as well as muscle-like) and gut muscle cells derive from the common progenitor cells of the embryonic gut unifying the histogenetic concept of all GIST with heterogeneous cytomorphologic features. In this review we attempted to incorporate recent information on interstitial Cajal-like cells (ICLC) found in other organs to broaden our understanding of ICC in general in terms of their ultrastructure, physiology, and neoplasia.

Expression of cyclooxygenase-2 in breast carcinogenesis and its relation to HER-2/neu and p53 protein expression in invasive ductal carcinoma

The purpose of this study was to evaluate cyclooxygenase-2 (COX-2) expression in the successive steps of breast carcinogenesis and to determine its correlation with HER-2/neu and p53 expression in invasive ductal carcinomas of the breast. Immunohistochemical staining with anti-COX-2 antibody was performed in normal breast tissue, usual hyperplasia, ductal carcinoma in situ, and invasive ductal carcinoma. Expression of COX-2 in invasive ductal carcinoma was correlated with immunohistochemical expression of HER-2/neu and p53 protein. COX-2 expression was found to be progressively elevated along the continuum from normal breast tissue to invasive ductal carcinoma (P<0.001). COX-2 expression significantly correlated with p53 and HER-2/neu protein expression (P<0.05 and P<0.001). On multivariate analysis, only TNM stage and elevated COX-2 expression correlated with survival. Our results suggest that COX-2 may be involved in the carcinogenesis of the breast and may be an independent prognostic indicator in patients with invasive ductal carcinoma. HER-2/neu and p53 are likely to be involved in the regulation of COX-2 expression in invasive ductal carcinomas of the breast.

Expression of cyclooxygenase-2 in epithelial ovarian tumors and its relation to vascular endothelial growth factor and p53 expression

The purpose of this study was to evaluate cyclooxygenase-2 (COX-2) expression in epithelial ovarian tumors and its correlation with vascular endothelial growth factor (VEGF) and p53 expression. Immunohistochemical studies with anti-COX-2, anti-VEGF, and anti-p53 antibodies were carried out in 54 malignant and 23 borderline epithelial ovarian tumors. Elevated COX-2 expression was detected in 77.8% of ovarian carcinomas, which was significantly higher than that of borderline tumors (26.1%) (P < 0.001). In ovarian carcinomas, there was no significant correlation between COX-2 expression and other clinicopathologic features. Elevated VEGF expression was detected in 74.1% of ovarian carcinomas, and p53 expression was found in 64.8% of ovarian carcinomas. COX-2 expression was statistically correlated with elevated VEGF expression (P < 0.001) and p53 positivity (P < 0.05). On a univariate analysis, FIGO stage (P < 0.0001), histologic type (P= 0.0104), and COX-2 expression (P= 0.0135) were significant prognostic factors for overall survival. In a multivariate analysis, FIGO stage (P < 0.0001) was the only independent prognostic factor for poor survival. These findings suggest that COX-2 may play a role in the progression of epithelial ovarian tumors and that COX-2 expression may contribute to ovarian tumor angiogenesis by stimulating VEGF expression. p53 may be responsible for the regulation of COX-2 expression.

Mammary pseudoangiomatous stromal hyperplasia presenting as an axillary mass

Pseudoangiomatous stromal hyperplasia (PASH) of the breast is characterized by interanastomosing slit-like spaces lined with spindle-shaped cells in an abundant fibrous stroma. PASH is a relatively common incidental finding in the breast tissue removed for other reasons and rarely presents as a localized mass. The etiology of PASH is unknown, but hormonal factors are thought to be involved. Accessory breast tissue is subject to all pathologic changes found in the normal breast. We report a case of PASH that presented as a palpable axillary mass in a 43-year-old woman. To our knowledge, PASH has not previously been reported in the axillary accessory breast tissue. The spindle stromal cells in our patient showed immunophenotypic characteristics of myofibroblastic differentiation. Immunoreactivity for progesterone receptor was noted in the spindle cells. These findings support the hypothesis that endogenous hormones are involved in the development of PASH.

The role of β-catenin, TGFβ3, NGF2, FGF2, IGFR2, and BMP4 in the pathogenesis of mesenteric sclerosis and angiopathy in midgut carcinoids

A subset of midgut carcinoids (MCs) result in mesenteric angiopathy (MA) and bowel infarction as a consequence of vascular compression caused by extensive mesenteric sclerosis (MS). The goal of this study was to determine whether the level of expression of several fibrosing-related growth factors was related to the finding of MA and/or MS in MCs. Eighteen cases of MC, 6 with both extensive MS and MA (group I), 5 with extensive MS only (group II), and 7 with ordinary MS only (group III), were analyzed for immunoexpression of beta-catenin, transforming growth factor-beta 2 (TGF beta 2), nerve growth factor 2 (NGF2), fibroblast growth factor 2 (FGF2), insulin growth factor receptor (IGFR), and bone morphogenic protein 4 (BMP4) in formalin-fixed, paraffin-embedded sections. Standard immunohistochemical technique was used following antigen retrieval. Immunostaining was scored semiquantitively as the product of the percentage and intensity (0 to 2+) of the immunostaining, giving a possible range of 0 to 200. One-way analysis of variance and Mann-Whitney nonparametric analyses were used for statistical analysis. The mean scores of immunoreactivity of each factor in groups I, II, and III were as follows: 135, 174, and 147 for beta-catenin (cytoplasmic reactivity only); 106, 112, and 92 for TGF beta 3; 1.67, 32, and 36 for NGF-2; 2.5, 48, and 55 for FGF-2; 19, 112, and 66 for IGFR2; 140, 45, and 52 for BMP4. There were significant differences in NGF-2 immunoreactivity between groups I and III (P = 0.0023) and in BMP4 immunoreactivity between groups I and II (P = 0.017) and groups I and III (P = 0.022). All MCs expressed high levels of membranous beta-catenin, moderate levels of TGF beta 3 and IGFR2, and low levels of FGF-2, with no significant differences seen among the groups. MCs with prominent MS and MA (group I) expressed significantly higher BMP4 than those in groups II and III, suggesting a potential role of BMP4 in the pathogenesis of MA. The level of NGF-2 expression was significantly lower in group I than in group III, possibly indicating abnormal angiogenesis in the formation of angiopathy.

Multiple small intestinal stromal tumours in a patient with previously unrecognised neurofibromatosis type 1: immunohistochemical and ultrastructural evaluation

Neurofibromatosis type 1 could be associated with multiple gastrointestinal stromal tumours, although their presence is not considered among the major diagnostic criteria. We present here a case of a 50-year-old female complaining of abdominal pain, with about 100 small intestinal stromal tumours. This finding prompted us to suspect a neurofibromatosis which was clinically confirmed afterwards. Light microscopy examination revealed a low-grade stromal tumour with skeinoid fibres. Mixed neural-interstitial cells of Cajal origin or, alternatively, neural differentiation of interstitial cells of Cajal are discussed on the basis of immunophenotype (CD117+, CD34+) and ultrastructure. A 2-year follow-up did not indicate an aggressive course in the case of this neoplasm.

Multiple small intestinal stromal tumours in a patient with previously unrecognised neurofibromatosis type 1: immunohistochemical and ultrastructural evaluation

Neurofibromatosis type 1 could be associated with multiple gastrointestinal stromal tumours, although their presence is not considered among the major diagnostic criteria. We present here a case of a 50-year-old female complaining of abdominal pain, with about 100 small intestinal stromal tumours. This finding prompted us to suspect a neurofibromatosis which was clinically confirmed afterwards. Light microscopy examination revealed a low-grade stromal tumour with skeinoid fibres. Mixed neural-interstitial cells of Cajal origin or, alternatively, neural differentiation of interstitial cells of Cajal are discussed on the basis of immunophenotype (CD117+, CD34+) and ultrastructure. A 2-year follow-up did not indicate an aggressive course in the case of this neoplasm.

Spindle cell carcinoids of the lung with paraganglioid features: a reappraisal of their histogenetic origin from paraganglia using immunohistochemical and electronmicroscopic techniques

Five cases of spindle cell carcinoids of the lung were analyzed by immunohistochemical and ultrastructural technique. They were found to be biphasic tumors composed of the major component of neuroendocrine cells (chief cells) and a minor component of dendritic cells (supporting cells). The chief cells displayed positivity for neuroendocrine phenotypic antigenic markers: neuron specific enolase (NSE), chromogranin A, and synaptophysin. They contained varying numbers of dense-core granules by electron microscopy. In addition, the chief cells expressed cytoplasmic positivity for cytokeratins. The supporting cells were dendritic in appearance and displayed strong positivity for S-100 protein in all cases. Glial fibrillary acidic protein was positive in two cases. On electron microscopy, the supporting cells were agranular and found along the external lamina surrounding the nests of tumor cells. In two cases, rare ganglion cell-like cells were present. The histomorphologic, immunohistochemical, and ultrastructural features were contrastingly different from the classical pulmonary carcinoid and rather resembled gangliocytic paragangliomas arising from small intestine and spine. It is proposed that pulmonary carcinoids with biphasic features are better designated as gangliocytic paragangliomas of the lung rather than paraganglioid carcinoids.

True histiocytic lymphoma of the esophagus in an HIV-positive patient: an ultrastructural study

A 56-year-old white woman, seropositive for human immunodeficiency virus for 18 months without signs of acquired immunodeficiency syndrome, presented with retrosternal pain and progressive dysphagia secondary to an exophytic esophageal mass. Biopsies of the tumor showed a malignant neoplasm composed of pleomorphic, noncohesive cells growing in a diffuse, sheet-like fashion. Immunohistochemically, tumor cells were nonreactive with epithelial, lymphoid, neural, and monocyte/macrophage markers. Despite the noncontributory immunohistochemical findings, ultrastructural study of the tumor cells revealed convincing histiocytic features. Individual cells possessed long, slender filopodial projections, prominent Golgi apparatus, residual bodies, rare lysosomes, and prelysosomes. Immunoglobulin heavy chain and T-cell receptor gamma gene rearrangement studies detected no evidence of a clonal gene rearrangement. The patient responded poorly to chemotherapy and died 5 months after her initial symptom of dysphagia.

Renal oncocytosis: a morphologic study of fourteen cases

Diffuse renal involvement by numerous oncocytic nodules has rarely been described. We report 14 cases (19 specimens) with innumerable oncocytic nodules in the kidney. Invariably, these kidneys showed additional associated findings. We suggest the term renal oncocytosis for this entire morphologic spectrum. Six (43%) cases had histologically or radiologically proven bilateral involvement. Each specimen had at least one dominant tumor (2.0-10.5 cm) in addition to numerous other microscopic to macroscopic oncocytic nodules. Additional features observed were: interstitial pattern, with the oncocytic tubules and acini diffusely intermingling with and infiltrating between non-neoplastic parenchyma (one case); diffuse oncocytic change in the nonneoplastic tubules, cytologically difficult to separate from the oncocytic nodules (seven cases); and benign oncocytic cortical cysts (four cases). The dominant mass in 13 specimens was a renal oncocytoma and in two, a chromophobe renal cell carcinoma. In four specimens, the largest tumor was considered a hybrid tumor because of the presence of mixed histologic features of both tumor types. Most smaller nodules had the morphologic features of renal oncocytoma, but a few had the appearance of chromophobe renal cell carcinoma or nodules with hybrid features. We conclude that the presence of numerous oncocytic nodules may be associated with a wide spectrum of oncocytic changes in the kidney. The association of numerous renal oncocytoma-like nodules with lesions having a mixed morphology or a morphology of pure chromophobe renal cell carcinoma suggests that they may constitute a morphologic spectrum of oncocytic tumors and that renal oncocytoma and chromophobe renal cell carcinoma may arise from a common progenitor lesion.

Intramuscular hemangioma: a benign tumor masquerading as malignant soft tissue tumor. Report of two cases

We report two cases of intramuscular hemangiomas, one arising from the left flank region of a 33-year-old female, and another from the mid right back of a 25-year-old man. In both cases the tumor masqueraded as malignancy and required a biopsy for correct diagnosis. Intramuscular hemangioma is a benign vascular tumor. Its tendency to deep location, infiltrative border, and fixity to surrounding tissues may cause it to be confused with malignant soft tissue tumors. Preoperative biopsy of the lesion is advised, and histopathologic examination is the only way to make a definitive diagnosis. Wide excision of the lesion is the treatment of choice. Follow up is required for any late recurrences.

Diagnostic usefulness of sustentacular cells in paragangliomas: immunocytochemical and ultrastructural investigation

Neuroendocrine tumors may derive either from neuroectoderm or endoderm. Both may present with a similar histologic pattern known as "Zellballen" regardless of their histogenetic origin, making it difficult to separate the two different histogenetic entities in certain cases. To evaluate the usefulness of sustentacular cells in the recognition of tumors of paraganglionic origin, the authors analyzed immunohistochemical and ultrastructural characteristics of 25 paragangliomas and 19 pulmonary and 10 small intestinal carcinoids. Sustentacular cells with characteristic dendritic features, strong immunoreactivity for S-100 protein, and agranular cytoplasm by electron microscopy were found consistently in the paragangliomas and not found in typical carcinoid tumors, except for four examples of spindle cell carcinoid of the lung. The presence of sustentacular cells in tumors with "Zellballen" pattern therefore denotes paraganglionic origin.

Culture-negative endocarditis caused by Bartonella henselae

A 4-year-old girl presented with clinical evidence of infective endocarditis involving her aortic valve, but blood cultures were sterile. Serologic studies and analysis of resected valve by immunohistochemistry and polymerase chain reaction established the diagnosis of Bartonella henselae endocarditis. Clinicians should be aware that B. henselae can cause apparent culture-negative endocarditis in children.

Gangliocytic paraganglioma of the duodenum: report of a case with immunocytochemical and ultrastructural investigation

A case of gangliocytic paraganglioma is reported in a 70-year-old female presenting as a polypoid tumor of the second portion of the duodenum. Immunohistochemical and ultrastructural features of the tumor indicate that gangliocytic paraganglioma of the duodenum (GPD) represents an unique tumor originating from the neuroectodermal derivative exhibiting dual phenotypic expression toward paraganglionic and epithelial (neuroendocrine) cells. These findings correlate well with the literature and it is further suggested that GPD belongs to the histopathologic spectrum of tumors derived from the neural crest. The findings offer a plausible explanation for histogenetic possibilities of the occurrence of pure epithelial tumors (i.e., carcinoid-like tumors) in the paraganglionic systems. The patient remains with no evidence of disease 4 years following a simple polypectomy.

Skeinoid fibers in mesectodermal leiomyoma of the ciliary body

Unlike smooth muscle elsewhere in the body, the smooth muscle of the iris and ciliary body is derived from neuroectoderm (mesectoderm). Leiomyomas that arise from the ciliary body, and therefore are of mesectodermal origin, may resemble spindle cell neurogenic tumors by light microscopy. They show positive immunostaining for smooth muscle actin but negative staining for neural markers. Ultrastructurally, the cells have the features of smooth muscle cells. The authors report a typical case of mesectodermal leiomyoma in a 47-year-old woman in which skeinoid fibers, considered to be an ultrastructural marker of neurogenic spindle cell tumors, were frequent together with other ultrastructural features often seen in neuroglial cell tumors. The findings indicate that mesectodermal leiomyoma is unique in its histogenesis as well as in its morphology.

Primary endodermal sinus tumor of the vulva: a case report and review of the literature

BACKGROUND

Extragonadal endodermal sinus tumors arising in the external genitalia represent an exceedingly rare malignancy in women. Six cases of endodermal sinus tumors of the vulva have been reported to date, with three cases failing to respond to conservative surgery and vincristine-based chemotherapy. We report a seventh case of vulvar endodermal sinus tumor that was treated with radical surgery and platinum-based chemotherapy.

CASE

RT is an 18-year-old female who presented with a vulvar mass that was diagnosed as endodermal sinus tumor at the time of biopsy. She was subsequently treated with modified radical vulvectomy and ipsilateral groin lymphadenectomy, followed by bleomycin, etoposide, and cisplatin chemotherapeutic regimen. She has since remained free of disease for 18 months as evidenced by serum alpha-fetoprotein and physical exam at 18 months.

CONCLUSIONS

Vulvar endodermal sinus tumors represent a very small number of germ cell tumors in women. Based on the previous accounts, this disease appears to be more fatal than endodermal sinus tumor arising at other sites. These tumors also have a predilection for local metastasis. Due to the previous accounts, we chose to treat this patient with radical surgery and platinum-based chemotherapy. This treatment regimen has resulted in a disease-free state for 18 months.

Solitary fibrous tumors: a series of lesions, some in unusual sites

Solitary fibrous tumor (SFT) is a rare neoplasm that, in addition to its classic presentation as a pleural-based mass, can also be encountered in unusual sites. The main difficulty in making the diagnosis of SFTs results from the unfamiliarity with its diverse clinical and pathologic features. This series of SFTs, some with unusual clinicopathologic presentation, included nine women and two men, ranging in age from 28 years to 74 years (five in pleura, one in lung parenchyma, one in breast, and four in mediastinum). The tumors were locally excised in eight cases and were resected along with portions of lung parenchyma in three. A panel of immunohistochemical stains was used to characterize these tumors. They were all vimentin-positive and, with the exception of one case, CD34-positive. Tumors were negative with antibodies directed against cytokeratin, factor VIII-related antigen, S-100 protein, muscle-specific actin, and smooth-muscle actin. Various diagnoses were initially rendered for these clinically and pathologically diverse lesions by the examining pathologists. Awareness of the various gross and microscopic patterns of these tumors, the possibility of occurring in unusual sites, and the use of immunohistochemical stains, particularly CD34, should eliminate most of the difficulties in arriving at a correct diagnosis. One patient died of metastatic breast cancer; all other patients were alive and well with a median follow-up of 17 months.

Clear cell ependymoma: a mimic of oligodendroglioma: clinicopathologic and ultrastructural considerations

Although clear cells resembling oligodendrocytes are known to occur in ependymomas, tumors composed primarily of such cells, i.e., clear cell ependymoma (CCE), are rare. Herein we characterize the clinicopathologic features of eight examples of CCE encountered at Mayo Clinic from 1983 to 1996. The tumors occurred in patients 3-31 years of age and presented as well-demarcated, deeply situated, contrast-enhancing masses, all of which were supratentorial. All but one case lacked classic light microscopic features of ependymoma. Although nearly all were immunoreactive for glial fibrillary acidic protein, it was electron microscopy that showed the diagnostic hallmarks of ependymoma, including complex intercellular junctions, surface microvilli and cilia, and microrosette formation, thus underscoring the importance of electron microscopy in the diagnosis of clear cell ependymomas. The differential diagnosis of CCE includes not only oligodendroglioma, but central neurocytoma and glioneurocytoma. Unlike oligodendrogliomas, CCEs are characterized by their sharp circumscription, hypervascularity as reflected in contrast enhancement on computed tomography and magnetic resonance imaging, their noninfiltrative pattern of growth that displaces parenchyma, and the occasional formation of vague perivascular pseudorosettes. Unlike central neurocytomas and glioneurocytomas, CCE lack secretory granules, vesicles, and synapses by electron microscopy and neuroendocrine markers by immunocytochemistry. In summary, the diagnosis of CCE requires neuroimaging, histologic, and ultrastructural correlation. The latter is essential in a limited biopsy. Ultrastructural studies also play a role in identifying glioneurocytomas. CCEs behave like more ordinary ependymomas. The importance of their recognition is the avoidance of alternative diagnoses and inappropriate therapies.

Epidermal growth factor receptor in vulvar malignancies and its relationship to metastasis and patient survival

OBJECTIVE

To evaluate the level of epidermal growth factor receptor (EGF-R) expression in vulvar malignancies and to determine if a correlation exists between EGF-R levels and metastasis or patient survival.

METHODS

All patients with a diagnosis of invasive squamous cell carcinoma of the vulva who were treated at our institution with a primary radical vulvectomy and inguinal lymph node dissection from 1983 to 1993 were eligible for the study. Sixty-one patients with available tissue blocks of benign vulvar epithelium, the primary malignant vulvar lesion, and groin node metastasis (when positive) were included in the study. Semiquantitative EGF-R expression was determined in a blinded fashion utilizing immunohistochemical staining of appropriate tissue samples. Survival was calculated utilizing Kaplan-Meier life table analysis based upon disease-free survival.

RESULTS

A significant increase (P < 0.001) in mean EGF-R levels was demonstrated in the primary tumor (67%) versus benign vulvar epithelium (31%). In the 14 patients with lymph node metastasis, the mean EGF-R level in the primary tumor was 65% versus 88% in the metastatic lesion (P < 0.001). The likelihood of lymph node metastasis was elevated in those patients with a benign tissue EGF-R level > or =40% (P < 0.03) and in those patients with a primary tumor EGF-R level > or =90% (P < 0.025). Life table analysis revealed a cumulative disease-free survival of 45% for all patients. Disease-free survival in those patients with EGF-R levels > or =90% in the primary tumor was 25%, contrasting with a disease-free survival of 54% in those patients with EGF-R levels <90% (P < 0.05).

CONCLUSIONS

There is a progressive increase in EGF-R expression from benign vulvar epithelium to primary malignant tissue to metastatic lesions within the same patient. Increased expression of EGF-R in the primary vulvar malignancy is significantly associated with lymph node metastasis and decreased patient survival. Increased expression of EGF-R in histologically benign vulvar epithelium has a significant association with lymph node metastasis and may predict decreased patient survival.

Survey of sinonasal inverted papillomata for Epstein-Barr virus

BACKGROUND

Several studies have indicated an etiologic role for viruses in the development of sinonasal inverted papillomata (IP). A recent report demonstrates a strong relationship (65%) between Epstein-Barr virus (EBV) and these lesions using polymerase chain reaction (PCR) analysis.

METHODS

The present study analyzes a series of paraffin-embedded tissues, comprising 25 surgically resected IPs and four fungiform papillomata (FP) for the presence of EBV using a sensitive in situ hybridization (ISH) assay and PCR.

RESULTS

None of the specimens examined showed evidence of EBV infection by ISH, and only two papillomata (one sinonasal IP and one FP) gave positive reactions for EBV using PCR.

CONCLUSIONS

These data challenge the previous report and suggest that EBV is not a significant etiopathologic factor to be considered in the development of sinonasal IP.

Immunohistochemical assessment of proliferation markers and altered gene expression in archival specimens of ovarian epithelial tumors

Recently reported morphologic and molecular genetic evidence suggests that some ovarian carcinomas arise from their benign and low malignant potential (LMP) counterparts. In order to help reach a better understanding of ovarian tumorigenesis, we studied a wide range of gene products involved in cellular growth regulation in archival material obtained from three groups of tumors with graduated malignant potential. Immunohistochemical staining was performed for Ki-67, proliferating cell nuclear antigen (PCNA), epidermal growth factor receptor (EGFR), HER-2/neu-encoded receptor protein, p53 gene product, and multidrug resistance gene product (P-glycoprotein). The expression of EGFR, HER-2/neu-encoded receptor protein, and mutant p53 product was significantly lower in LMP tumors than in carcinomas (p < 0.05). HER-2/neu immunopositivity was more prevalent in adenocarcinomas than in LMP tumors, and the proportion of HER-2/neu-positive adenocarcinomas increased with the progression of the disease. The staining differences between LMP tumors and adenocarcinomas with antibodies against Ki-67, PCNA, and P-glycoprotein were not statistically significant. Immunohistochemical detection of EGFR, HER-2/neu, and p53 in ovarian epithelial tumor is relevant to ovarian tumorigenesis. It could serve as a powerful tool for the pursuit of retrospective studies focused on these important biologic markers.

P-glycoprotein as a prognostic indicator in pre- and postchemotherapy ovarian adenocarcinoma

P-glycoprotein (P-gp) is a plasma membrane efflux transporter that maintains the intracellular concentration of chemotherapeutic agents at low levels. Since the clinical outcome of ovarian adenocarcinoma depends largely on its response to chemotherapy, an objective assessment of P-gp expression could serve as a prognostic indicator. Eighty-five patients were studied. Available tissue sections from the primary tumor (n = 75) and persistent or recurrent lesions (n = 19) were tested with anti-P-gp (JSB-1) monoclonal IgG. Multivariate survival analysis using Cox regression was performed controlling for fixed covariates (age, surgical stage, and presence of residual tumor) and included occurrence of postchemotherapy tumors and P-gp positivity in postchemotherapy neoplasms as time-dependent variables. P-gp was expressed in 49 prechemotherapy (65.3%) and 14 postchemotherapy (73.7%) tumors. After controlling for potentially confounding factors, patients with P-gp-positive postchemotherapy neoplasms were at three times greater risk of dying within 2 years than their counterparts with P-gp-negative tumors (hazard ratio = 3.1: 95% confidence interval = 1.2, 9.1; p < 0.05). Detection of P-gp-expressive subclones can serve as an independent poor prognostic indicator for patients with postchemotherapy tumors.

Cellular hemangioma of the posterior mediastinum: unusual presentation of a rare vascular neoplasm

Cellular hemangiomas arising in the posterior mediastinum (or paravertebral sulcus) are rare tumors even in childhood. We report one such tumor which arose within a sympathetic ganglion in an infant with associated congenital heart disease (ventricular septal defect) and severe congestive heart failure. The tumor was discovered incidentally at cardiac catheterization when tumor blush was observed in the apex of the left chest. This benign mass was completely resected prior to repair of the cardiac defect. We speculate that it may have contributed to the congestive heart failure.

A deficit of chondroitin sulfate proteoglycans on the bladder uroepithelium in interstitial cystitis

OBJECTIVES

To investigate the abundance of chondroitin sulfate proteoglycans at the bladder lumenal and subepithelial surfaces in bladder biopsies derived from patients with interstitial cystitis (IC) and controls.

METHODS

Tissue sections derived from biopsies from 31 IC patients and 24 pathologically normal control sections were labeled for proteoglycans using the 2B6 anti-"stub" antibody and detected by immunohistochemistry.

RESULTS

On the lumenal surface, 5 of 31 (19%) IC sections were positive for proteoglycans versus 14 of 24 (58%) control sections (P = 0.00011). At the basal surface, 5 of 19 IC patients were positive versus 7 of 12 controls (P = 0.032).

CONCLUSIONS

A deficit of bladder lumenal and basal proteoglycans is associated with IC. The deficit in basal layer proteoglycans suggests an altered urothelial differentiation program. The lumenal deficit suggests that the charge-dependent exclusion of ions from the bladder surface is compromised in IC.

Epstein-Barr virus-associated gastric adenocarcinomas among Koreans

Epstein-Barr virus (EBV)-associated gastric carcinomas have been reported from various regions of the world. Epstein-Barr virus appears to be pathogenetically related to some gastric carcinomas. To determine the incidence of EBV association with gastric carcinomas among Koreans, the authors have studied EBV genome expression in 89 consecutive patients with gastric carcinomas diagnosed at the Catholic University Hospitals in Seoul, Korea, using in situ hybridization (ISH) for EBV-encoded small RNAs (EBERs), and immunohistochemistry for EBV latent membrane proteins (LMP) and CD21 antigen on paraffin sections. Thirty-seven gastric specimens with benign ulcer disease were used controls. EBV-encoded small RNAs were expressed in tumor cell nuclei in 12 patients (13.5%). None of the controls or benign portions of the cases were positive. In the positive cases, all tumor cell nuclei were uniformly stained and the staining intensity was strong. Immunohistochemistry for LMP was positive in 3 of 12 EBERs positive patients and none of EBERs negative patients. EBV latent membrane proteins was localized only in the lymphoid cells infiltrating the tumor in two patients, and tumor cells as well as infiltrating lymphoid cells in one patient. These results indicate that the rate of EBV association with gastric carcinomas in Koreans is relatively high and comparable to other Far Eastern Asian regions. The expression pattern in EBV-associated gastric carcinomas is similar to those of nasopharyngeal carcinomas in which clonality analysis using specific probes to the tandem repeat region of EBV yielded single episomal bands suggesting that EBV infection in EBV-associated gastric carcinomas are also clonal and pathogenetically related to the neoplasm. However, the mechanism of tumorigenesis remains to be elucidated.