Subacute exposure to N-ethyl perfluorooctanesulfonamidoethanol results in the formation of perfluorooctanesulfonate and alters superoxide dismutase activity in female rats.

Perfluorooctanesulfonamides, such as N-ethyl perfluorooctanesulfonamidoethanol (N-EtFOSE), are large scale industrial chemicals but their disposition and toxicity are poorly understood despite significant human exposure. The hypothesis that subacute exposure to N-EtFOSE, a weak peroxisome proliferator, causes a redox imbalance in vivo was tested using the known peroxisome proliferator, ciprofibrate, as a positive control. Female Sprague-Dawley rats were treated orally with N-EtFOSE, ciprofibrate or corn oil (vehicle) for 21 days, and levels of N-EtFOSE and its metabolites as well as markers of peroxisome proliferation and oxidative stress were assessed in serum, liver and/or uterus. The N-EtFOSE metabolite profile in liver and serum was in good agreement with reported in vitro biotransformation pathways in rats and the metabolite levels decreasing in the order perfluorooctanesulfonate >> perfluorooctanesulfonamide ~ N-ethyl perfluorooctanesulfonamidoacetate >> perfluorooctanesulfonamidoethanol approximately N-EtFOSE. Although N-EtFOSE treatment significantly decreased the growth rate, increased relative liver weight and activity of superoxide dismutases (SOD) in liver and uterus (total SOD, CuZnSOD and MnSOD), a metabolic study revealed no differences in the metabolome in serum from N-EtFOSE-treated and control animals. Ciprofibrate treatment increased liver weight and peroxisomal acyl Co-A oxidase activity in the liver and altered antioxidant enzyme activities in the uterus and liver. According to NMR metabolomic studies, ciprofibrate treated animals had altered serum lipid profiles compared to N-EtFOSE-treated and control animals, whereas putative markers of peroxisome proliferation in serum were not affected. Overall, this study demonstrates the biotransformation of N-EtFOSE to PFOS in rats that is accompanied by N-EtFOSE-induced alterations in antioxidant enzyme activity.

Altered expression of iron regulatory genes in cirrhotic human livers: clues to the cause of hemosiderosis?

Hepatic iron deposition unrelated to hereditary hemochromatosis occurs commonly in cirrhosis but the pathogenesis of this condition is unknown. The aim of this study was to compare the expression of genes involved in the regulation of iron metabolism in cirrhotic (n=22) and control human livers (n=5). Transcripts were quantitated by real-time RT-PCR and protein levels were assessed by western blot. Hepatic iron concentrations (HICs) were measured by a spectrophotometric method. Levels of hepcidin mRNA did not differ between controls and cirrhotic livers; there was a highly significant correlation between hepcidin transcript levels and HIC in the latter group. Ferroportin, divalent metal transporter-1 (DMT1), and ferritin heavy chain mRNA levels were significantly higher in cirrhotic human livers than in controls (P=0.007, 0.039, and 0.025, respectively). By western blot, ferroportin and DMT1 levels were generally diminished in the cirrhotic livers compared to controls; neither correlated with HIC. In contrast, the abundance of ferritin increased with increasing HIC in the cirrhotic livers, whereas transferrin receptor decreased, indicating physiologically appropriate regulation. In conclusion, hepcidin expression appears to be appropriately responsive to iron status in cirrhosis. However, there are complex alterations in DMT1 and ferroportin expression in cirrhotic liver, including decreases in ferroportin and DMT1 at the protein level that may play a role in aberrant regulation of iron metabolism in cirrhosis.

Regulation of 14-3-3sigma expression in human thyroid carcinoma is epigenetically regulated by aberrant cytosine methylation.

Increased 14-3-3sigma expression has been observed by immunohistochemistry in papillary and anaplastic tumors, but not follicular thyroid cancers. 14-3-3sigma mRNA expression and methylation status was examined in tumor cell lines and primary thyroid tissues using real-time RT-PCR, bisulfite sequencing and methylation-specific PCR. Most of the 27 CpG's in the gene's CpG island were methylated in normal thyroid, TPC-1, NPA, FTC-238 and 2-7, which did not express 14-3-3sigma. In contrast, they were unmethylated in KAK-1 and anaplastic lines KAT4 and DRO-90. 14-3-3sigma expression was not increased in thyroid carcinomas, the majority of which had a methylated CpG island. In addition, 5-aza-dC treatment increased 14-3-3sigma expression in the FTC-238 and NPA cell lines, which had low baseline expression. We conclude 14-3-3sigma expression in thyroid carcinomas is regulated by CpG island hypermethylation.

Immunohistochemical expression of osteopontin in epithelioid mesotheliomas and reactive mesothelial proliferations.

The morphologic distinction of epithelioid mesothelioma from a reactive mesothelial proliferation can be difficult. Recent studies have demonstrated that serum osteopontin levels are increased in patients with mesotheliomas. We sought to determine if osteopontin expression is diagnostically helpful in distinguishing epithelioid mesothelioma from reactive mesothelial proliferations. We studied 7 cases of epithelioid mesothelioma and 20 cases of reactive mesothelial proliferations by immunohistochemical analysis using standard technique. All 7 mesotheliomas and 19 of 20 reactive mesothelial proliferations showed osteopontin expression. Osteopontin expression is not restricted to malignant mesothelial proliferations, and immunohistochemical analysis for osteopontin is not helpful in determining reactive vs malignant mesothelial proliferations. The reported usefulness of osteopontin as a serum tumor marker for mesothelioma may be due to differences in the amount or character of secreted protein in malignant mesothelioma compared with reactive mesothelial proliferations.

A preliminary diagnosis service provides prospective blinded dual-review of all general surgical pathology cases in an academic practice.

Quality assurance of diagnostic accuracy in surgical pathology is an important part of a pathologist's total quality management program. At our academic institution, the quality of diagnostic accuracy is monitored via dual-review of every general surgical pathology case, which accounts for nearly 20,000 cases per year. This comprehensive dual-review is achieved by operating a preliminary diagnosis service, staffed by a senior or board eligible resident. Analysis of a portion of our dual-review data (6300 cases) demonstrates an overall diagnostic concordance rate of 95.4% and a clinical major discrepancy rate of 0.29% between the preliminary diagnosis and staff pathologist diagnosis, comparable to other published rates. The incorporation of a preliminary diagnosis service into our academic surgical pathology practice has proven to be beneficial with regard to quality assurance and resident education. Other academic institutions may similarly benefit from the addition of such a service.

Low-level endotoxin induces potent inflammatory activation of human blood vessels: inhibition by statins.

BACKGROUND: Low-level endotoxemia (ie, >or=50 pg/mL) in apparently healthy subjects was recently identified as a powerful, independent risk factor for atherosclerosis. METHODS AND RESULTS: We treated human saphenous veins (HSVs) with low levels of endotoxin. Release of the proinflammatory chemokines interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) was measured by ELISA. Superoxide was determined by using the fluorescent probe dihydroethidium (HE), and monocyte binding was assessed with calcein-labeled U-937 cells. Three- to 4-fold increases in MCP-1 and IL-8 release were observed at endotoxin concentrations of 100 pg/mL; these increases were inhibited by the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor atorvastatin. Studies in cultured endothelial cells suggest that the mechanism is related to inhibition of isoprenylation (ie, geranylgeranylation) rather than cholesterol formation. Endotoxin produced dose-dependent increases in HE fluorescence that were inhibited by the superoxide dismutase mimics Tiron and MnTBAP. Endotoxin potently induced U-937 cell binding to HSV; binding was inhibited by both Tiron and atorvastatin. Toll-like receptor-4 expression was detected in cultured HSV endothelial and smooth muscle cells and in intact HSV. CONCLUSIONS: Clinically relevant levels of endotoxin, as reported in ambulatory populations, have profound inflammatory effects on intact HSV. Inhibition of endotoxin-induced vascular inflammation might contribute to the beneficial effects of statins in treating atherosclerosis.

RABL6A Promotes Oxaliplatin Resistance in Tumor Cells and Is a New Marker of Survival for Resected Pancreatic Ductal Adenocarcinoma Patients.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by early recurrence following pancreatectomy, rapid progression, and chemoresistance. Novel prognostic and predictive biomarkers are urgently needed to both stratify patients for clinical trials and select patients for adjuvant therapy regimens. This study sought to determine the biological significance of RABL6A (RAB, member RAS oncogene family-like protein 6 isoform A), a novel pancreatic protein, in PDAC. Analyses of RABL6A protein expression in PDAC specimens from 73 patients who underwent pancreatic resection showed that RABL6A levels are altered in 74% of tumors relative to adjacent benign ductal epithelium. Undetectable RABL6A expression, found in 7% (5/73) of patients, correlated with improved overall survival (range 41 to 118 months with 3/5 patients still living), while patients with RABL6A expression had a worse outcome (range 3.3 to 100 months, median survival 20.3 months) (P = 0.0134). In agreement with those findings, RABL6A expression was increased in pancreatic cancer cell lines compared to normal pancreatic epithelial cells, and its knockdown inhibited pancreatic cancer cell proliferation and induced apoptosis. Moreover, RABL6A depletion selectively sensitized cells to oxaliplatin-induced arrest and death. This work reveals that RABL6A promotes the proliferation, survival, and oxaliplatin resistance of PDAC cells, whereas its loss is associated with extended survival in patients with resected PDAC. Such data suggest RABL6A is a novel biomarker of PDAC and potential target for anticancer therapy.

A process model for direct correlation between computed tomography and histopathology application in lung cancer.

RATIONALE AND OBJECTIVES: Multimodal imaging techniques for capturing normal and diseased human anatomy and physiology are being developed to benefit patient clinical care, research, and education. In the past, the incorporation of histopathology into these multimodal datasets has been complicated by the large differences in image quality, content, and spatial association. MATERIALS AND METHODS: We have developed a novel system, the large-scale image microtome array (LIMA), to bridge the gap between nonstructurally destructive and destructive imaging such that reliable registration between radiological data and histopathology can be achieved. Registration algorithms have been designed to align the multimodal datasets, which include computed tomography, computed micro-tomography, LIMA, and histopathology data to a common coordinate system. RESULTS: The resulting volumetric dataset provides an abundance of valuable information relating to the tissue sample including density, anatomical structure, color, texture, and cellular information in three dimensions. An image processing pipeline has been established to register all the multimodal data to a common coordinate system. CONCLUSION: In this study, we have chosen to use human lung cancer nodules as an example; however, the flexibility of the image acquisition and subsequent processing algorithms makes it applicable to any soft organ tissue. A novel process model has been established to generate cross registered multimodal datasets for the investigation of human lung cancer nodule content and associated image-based representation.

Recommendations for the reporting of surgically resected thymic epithelial tumors.

Thymic epithelial tumors include thymoma and thymic carcinoma. Histologic findings and extent of disease are key determinants of prognosis and help guide postoperative management in patients with thymic epithelial tumors. Given the relative rarity of these tumors, the use of tumor guidelines and checklists can facilitate accurate and comprehensive pathologic reporting in this setting. Diagnostic nomenclature (World Health Organization, Suster-Moran classifications) and staging criteria (modified Masaoka system) are emphasized.

Mandatory second opinion in cytopathology.

BACKGROUND: Mandatory review of outside pathologic material is intended to detect interpretive errors that may have a clinically significant impact on patient care. Prior to definitive treatment of referred patients, the University of Iowa Carver College of Medicine requires a review of pertinent pathologic material previously obtained at outside institutions. The aims of this study were to determine if this local standard of practice has a measurable impact on patient care. METHODS: The pathologic diagnoses of 499 second opinion cytology cases seen at the University of Iowa Carver College of Medicine were studied. Each second opinion was classified as "no diagnostic disagreement", "minor disagreement", or "major disagreement" with respect to the originating institution's interpretation. The clinical impact of major disagreement cases was determined by pathologic and clinical follow-up via chart review. RESULTS: Second opinion cytology resulted in 37 cases (7.4% of total cases) with major diagnostic disagreements. Clinical and pathologic follow-up was available in 30 of the major disagreement cases; second opinion diagnosis was better supported in 22 of these cases compared to the outside diagnosis. The second opinion in 6 major disagreement cases prompted changes in clinical management. CONCLUSIONS: Major disagreements in second opinion cytology are common, likely reflective of the challenges inherent in the interpretation of cytologic specimens. Although mandatory second opinion of outside cytologic material prompted changes in clinical management in only a small fraction of cases (1.2%), this rate was similar to those previously published for surgical pathology second opinion. These findings support the notion that mandatory second opinion policy as an important part of patient care.

Mandatory second opinion in surgical pathology referral material: clinical consequences of major disagreements.

Second opinion in pathology is intended to expose clinically significant errors that have a direct impact on patient care. Before definitive treatment of referred patients, our institution requires a second opinion of outside surgical pathology slides. We sought to determine if this local standard of practice has a measurable impact on patient care via clinical and pathologic follow-up. 5629 second opinion surgical pathology cases seen at the University of Iowa Hospitals and Clinics were studied. Each case was classified as: no diagnostic disagreement, minor diagnostic disagreement, or major diagnostic disagreement by the second opinion pathologist at the time of referral. A major diagnostic disagreement was defined as a change in pathologic diagnosis with potential for significant change in treatment or prognosis. Major diagnostic disagreements were categorized by organ system and according to the clinical significance of the changed diagnosis based on clinical and pathologic follow-up. Second opinion surgical pathology resulted in 132 (2.3% of total cases) major diagnostic disagreements and 507 (9.0%) cases with minor disagreements. The organ systems involved in the majority of the major disagreements were the female reproductive tract (32), gastrointestinal tract (27), and skin (24). Of the 132 major diagnostic disagreements, 68 (1.2% of total cases reviewed) prompted changes in the clinical management as a result of the second opinion interpretation. These findings support the idea that mandatory second opinion is an important part of patient care in the referral setting.

Generation and characterization of monoclonal antibodies to NIAM: a nuclear interactor of ARF and Mdm2.

Nuclear interactor of ARF and Mdm2 (NIAM) is a newly discovered growth inhibitor that helps maintain chromosomal stability. It is functionally linked to the ARF-Mdm2-p53 tumor suppressor pathway and is predicted to be a tumor suppressor, but the lack of antibodies capable of detecting the endogenous human protein has delayed efforts to define its role in human tumorigenesis. This study reports the development, screening, and characterization of several monoclonal antibodies (MAbs) that specifically recognize endogenous human NIAM protein by Western blotting, immunoprecipitation, immunofluorescence, and immunohistochemistry. These MAbs are predicted to be important tools for evaluating the expression and physiological function of NIAM in normal versus neoplastic human cells and tissues.

Small peripheral pulmonary adenocarcinoma: morphologic and molecular update.

The dichotomous histopathologic separation of lung carcinoma into "small cell" and "nonsmall cell" categories is validated by marked clinical and biologic differences between these groups of tumors. However, nonsmall cell carcinoma represents a heterogenous group of tumors, and the subclassification of nonsmall cell lung carcinoma at the molecular, morphologic, and epidemiologic levels has led to the promise of precise treatment and better prognostication. Histomorphologic aspects of small peripheral adenocarcinomas that represent good prognosis include pure bronchioloalveolar carcinoma, minimal invasion within a mixed invasive and lepidic growth pattern tumor, and minimal scar within a lepidic growth pattern tumor. Activating mutations and increased gene copy number of the epidermal growth factor receptor protein and locus, respectively, have been shown to help predict responsiveness to small molecule receptor tyrosine kinase inhibitors in lung adenocarcinoma. These important concepts of morphology and molecular pathology are reviewed, and recommendations for application of these concepts to the practice of surgical pathology are provided.

Comparison of fungal culture versus surgical pathology examination in the detection of Histoplasma in surgically excised pulmonary granulomas.

CONTEXT: Granulomatous pulmonary nodules are common in areas endemic for Histoplasma infection, and may require surgical excision to exclude neoplasia. Surgeons may elect to routinely send material directly to the clinical microbiology laboratory for fungal and mycobacterial cultures. OBJECTIVE: To determine if tissue from surgically excised pulmonary granulomatous nodules removed from patients in a geographic area endemic for Histoplasma infection should be routinely submitted for fungal culture. DESIGN: Retrospective review and comparison of surgical pathology histochemical findings and clinical microbiology results of 30 surgical (wedge) lung excisions that demonstrated granulomatous nodule at the time of frozen section. RESULTS: Twenty cases demonstrated fungal organisms consistent with Histoplasma species via histochemical fungal stains. Of these 20 cases, 17 were tested in the microbiology laboratory using direct smear examination and fungal culture; Histoplasma was detected in 1 case (1/17). Eight cases revealed no organisms by surgical pathology. Of these, 6 were tested in the microbiology laboratory, and all 6 were negative by culture and direct smear (0/6). The remaining 2 cases demonstrated organisms other than Histoplasma by surgical pathology examination. CONCLUSIONS: Surgical pathology examination of granulomatous pulmonary nodules detected Histoplasma organisms with greater sensitivity than culture and direct smear. There were no false-negative surgical pathology diagnoses when compared with microbiological results. These findings suggest that it is not necessary to routinely send material from solitary pulmonary granulomas for fungal culture when the material is removed from immunocompetent patients in a geographic area endemic for histoplasmosis.

Differential expression of stress-inducible proteins in chronic hepatic iron overload.

INTRODUCTION: Oxidative stress can trigger a cellular stress response characterized by induction of antioxidants, acute phase reactants (APRs) and heat shock proteins (HSPs), which are presumed to play a role in limiting tissue damage. In rodents, hepatic iron overload causes oxidative stress that results in upregulation of antioxidant defenses with minimal progressive liver injury. The aim of this study was to determine whether iron overload modulates expression of other stress-responsive proteins such as APRs and HSPs that may confer protection against iron-induced damage in rodent liver. METHODS: Male rats received repeated injections of iron dextran or dextran alone over a 6-month period. Hepatic transcript levels for a panel of APRs and HSPs were quantitated by real-time PCR and protein expression was evaluated by Western blot and immunohistochemistry. RESULTS: Hepatic iron concentrations were increased >50-fold in the iron-loaded rats compared to controls. Iron loading resulted in striking increases in mRNAs for Hsp32 (heme oxygenase-1; 12-fold increase vs. controls) and metallothionein-1 and -2 (both increased approximately 6-fold). Transcripts for alpha1-acid glycoprotein, the major rat APR, were increased approximately 3-fold, while expression of other classical APRs was unaltered. Surprisingly, although mRNA levels for the HSPs were not altered by iron, the abundance of Hsp25, Hsp70 and Hsp90 proteins was uniformly reduced in the iron-loaded livers, as were levels of NAD(P)H:quinone oxidoreductase 1, an Hsp70 client protein. CONCLUSIONS: Chronic iron administration elicits a unique pattern of stress protein expression. These alterations may modulate hepatic responses to iron overload, as well as other injury processes.

Subinvolution of the placental site as an anatomic cause of postpartum uterine bleeding: a review.

CONTEXT: Subinvolution of the placental site is an anatomic cause of delayed postpartum uterine bleeding that may be underrecognized by general surgical pathologists. OBJECTIVE: To review the physiology of uteroplacental arterial development and normal postpartum involution, and to present the characteristic clinical and histopathologic features of subinvolution. DATA SOURCES: Literature review (MEDLINE via PubMed and Ovid) regarding the pathology and pathophysiology of placental site subinvolution. Review of the clinical and pathologic characteristics of our own institution's previously diagnosed cases of subinvolution from hysterectomy and endomyometrial curettage specimens. CONCLUSIONS: Surgical pathologists must be aware of the cardinal histopathologic findings of subinvolution, and this diagnosis must be considered in every postpartum curettage or hysterectomy specimen presented to the surgical pathologist. Subinvolution of the placental site is an important diagnosis, as this process implies an idiopathic cause, rather than an iatrogenic cause, of postpartum uterine bleeding. The etiology of placental site subinvolution remains poorly characterized.

Chronic iron overload stimulates hepatocyte proliferation and cyclin D1 expression in rodent liver.

Hepatomegaly is commonly observed in hepatic iron overload due to human hemochromatosis and in animal models of iron loading, but the mechanisms underlying liver enlargement in these conditions have received scant attention. In this study, male rats were treated with iron dextran or dextran alone for 6 months. Chronic iron loading resulted in a > 50-fold increase in hepatic iron concentration. Both liver weights and liver/body weight ratios were increased approximately 2-fold in the iron-loaded rats (P < 0.001 for both). Hepatocyte nuclei expressing proliferating cell nuclear antigen (PCNA), a marker of S phase, were significantly increased in the iron-loaded livers, suggesting enhanced proliferation. To assess the mechanisms by which iron promotes proliferation, the expression of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, hepatocyte growth factor (HGF), and transforming growth factor-alpha (TGF-alpha) were assessed by reverse transcription-polymerase chain reaction (RT-PCR). Of these growth-associated factors, only TNF-alpha messenger RNA (mRNA) was significantly increased by iron loading (about 3-fold; P = 0.005). Because cyclin D1 is required for entry of hepatocytes into the cell cycle after partial hepatectomy or treatment with direct mitogens, levels of immunoreactive cyclin D1 were examined and found to be significantly increased in the iron-loaded livers. The increase in cyclin D1 protein in the iron-loaded livers was paralleled by an increase in the abundance of its transcript as measured by real-time PCR. Taken together, these results suggest that iron is a direct mitogen in the liver and raise the possibility that chronic stimulation of hepatocyte proliferation may play a role in the pathophysiology of iron overload states.

A simple, focused, computerized query to detect overutilization of laboratory tests.

CONTEXT: Although there is nearly universal agreement that laboratory tests are overutilized, the degree of overutilization in a given institution is difficult to quantify and monitor across time. OBJECTIVE: To detect and clearly document repetitive daily ordering of a commonly ordered laboratory test (serum sodium) by employing a simple, focused, computerized query of a test result database followed by chart review and validation. DESIGN: A retrospective computerized query of our clinical data repository was performed to find inpatients who displayed normal serum sodium test results on 4 or more consecutive days, without any abnormal values during the same admission. The search was limited to a 1-month period. A subset of these patients was selected for chart review. RESULTS: One hundred sixteen patients met our criteria, and the tests ordered for those patients comprised 5.1% of the monthly volume of serum sodium tests ordered in our institution. Chart review revealed a consistent lack of documentation of medical necessity for repeat testing as well as persistence of repeat serum sodium orders until the end of the patients' hospital course. CONCLUSIONS: We conclude that a focused query of data derived from a clinical data repository can detect and document overutilization of a common laboratory test in a convincing fashion within a given institution.