Treatment response in the PIVENS trial is associated with decreased Hedgehog pathway activity.

UNLABELLED: Hedgehog (Hh) ligand production by ballooned hepatocytes drives nonalcoholic steatohepatitis (NASH) progression in mice. The NIDDK-sponsored PIVENS trial (NCT00063622) showed that vitamin E (VitE) improved NASH. We investigated whether VitE treatment and improvement in NASH were associated with changes in Hh pathway activity. Immunohistochemistry (IHC) was performed on both pre- and posttreatment liver biopsies of 59 PIVENS patients randomized to VitE (n = 30) or placebo (n = 29). Sonic Hh (Shh) ligand-producing cells and Shh-responsive cells were quantified. The latter was accomplished by triple IHC for gli2+ (marker of Hh signaling), sox-9 (progenitor marker), and α-smooth muscle actin (α-SMA; myofibroblast marker). Ballooned hepatocytes were quantified by keratin 8/18 and ubiquitin (K8/18/Ub) staining. IHC results were correlated with primary clinical and histologic PIVENS data. Pretreatment clinical, histologic, and IHC parameters did not differ significantly in the two treatment groups. Regardless of treatment arm, the number of Shh+ hepatocytes correlated with K8/18/Ub foci (r(2) = 0.47, P < 0.001) and aspartate aminotransferase (AST) (r(2) = 0.15, P = 0.002). Treatment-related changes in the numbers of Shh+ hepatocytes correlated with changes in serum AST (partial r(2) = 0.75, P < 0.0001), hepatocyte ballooning (P = 0.004), the ductular reaction (i.e., numbers of gli2+/sox9+ cells; P = 0.03 and α-SMA+ cells; P = 0.10), and fibrosis stage (P = 0.02). Treatment response was associated with a greater decrease in Shh+ hepatocytes than nonresponse (P = 0.007). The VitE group demonstrated a greater reduction in K8/18/Ub+ foci (P < 0.08) and Shh+ hepatocytes (P < 0.05) than the placebo group, effects that became more significant after correction for baseline differences and multiple linear regression analysis. CONCLUSION: During PIVENS, treatment response correlated with loss of Shh+ hepatocytes and improvement in Hh-regulated processes that promote NASH progression.

Mutations in the gene that encodes the F-actin binding protein anillin cause FSGS.

FSGS is characterized by segmental scarring of the glomerulus and is a leading cause of kidney failure. Identification of genes causing FSGS has improved our understanding of disease mechanisms and points to defects in the glomerular epithelial cell, the podocyte, as a major factor in disease pathogenesis. Using a combination of genome-wide linkage studies and whole-exome sequencing in a kindred with familial FSGS, we identified a missense mutation R431C in anillin (ANLN), an F-actin binding cell cycle gene, as a cause of FSGS. We screened 250 additional families with FSGS and found another variant, G618C, that segregates with disease in a second family with FSGS. We demonstrate upregulation of anillin in podocytes in kidney biopsy specimens from individuals with FSGS and kidney samples from a murine model of HIV-1-associated nephropathy. Overexpression of R431C mutant ANLN in immortalized human podocytes results in enhanced podocyte motility. The mutant anillin displays reduced binding to the slit diaphragm-associated scaffold protein CD2AP. Knockdown of the ANLN gene in zebrafish morphants caused a loss of glomerular filtration barrier integrity, podocyte foot process effacement, and an edematous phenotype. Collectively, these findings suggest that anillin is important in maintaining the integrity of the podocyte actin cytoskeleton.

Histopathologic and immunohistochemical sequelae of bariatric embolization in a porcine model.

PURPOSE: To evaluate the histopathologic sequelae of bariatric embolization on the gastric mucosa and to correlate with immunohistochemical evaluation of the gastric fundus, antrum, and duodenum. MATERIALS AND METHODS: This study was performed on 12 swine stomach and duodenum specimens after necropsy. Of the 12 swine, 6 had previously undergone bariatric embolization of the gastric fundus, and the 6 control swine had undergone a sham procedure with saline. Gross pathologic, histopathologic, and immunohistochemical examinations of the stomach and duodenum were performed. Specifically, mucosal integrity, fibrosis, ghrelin-expressing cells, and gastrin-expressing cells were assessed. RESULTS: Gross and histopathologic evaluation of treatment animals showed healing or healed mucosal ulcers in 50% of animals, with gastritis in 100% of treatment animals and in five of six control animals. The ghrelin-immunoreactive mean cell density was significantly lower in the gastric fundus in the treated animals compared with control animals (15.3 vs 22.0, P < .01) but similar in the gastric antrum (9.3 vs 14.3, P = .08) and duodenum (8.5 vs 8.6, P = .89). The gastrin-expressing cell density was significantly lower in the antrum of treated animals compared with control animals (82.2 vs 126.4, P = .03). A trend toward increased fibrosis was suggested in the gastric fundus of treated animals compared with controls (P = .07). CONCLUSIONS: Bariatric embolization resulted in a significant reduction in ghrelin-expressing cells in the gastric fundus without evidence of upregulation of ghrelin-expressing cells in the duodenum. Healing ulcerations in half of treated animals underscores the need for additional refinement of this procedure.

Normal cardiac function in mice with supraphysiological cardiac creatine levels.

Creatine and phosphocreatine levels are decreased in heart failure, and reductions in myocellular phosphocreatine levels predict the severity of the disease and portend adverse outcomes. Previous studies of transgenic mouse models with increased creatine content higher than two times baseline showed the development of heart failure and shortened lifespan. Given phosphocreatine's role in buffering ATP content, we tested the hypothesis whether elevated cardiac creatine content would alter cardiac function under normal physiological conditions. Here, we report the creation of transgenic mice that overexpress the human creatine transporter (CrT) in cardiac muscle under the control of the α-myosin heavy chain promoter. Cardiac transgene expression was quantified by qRT-PCR, and human CrT protein expression was documented on Western blots and immunohistochemistry using a specific anti-CrT antibody. High-energy phosphate metabolites and cardiac function were measured in transgenic animals and compared with age-matched, wild-type controls. Adult transgenic animals showed increases of 5.7- and 4.7-fold in the content of creatine and free ADP, respectively. Phosphocreatine and ATP levels were two times as high in young transgenic animals but declined to control levels by the time the animals reached 8 wk of age. Transgenic mice appeared to be healthy and had normal life spans. Cardiac morphometry, conscious echocardiography, and pressure-volume loop studies demonstrated mild hypertrophy but normal function. Based on our characterization of the human CrT protein expression, creatine and phosphocreatine content, and cardiac morphometry and function, these transgenic mice provide an in vivo model for examining the therapeutic value of elevated creatine content for cardiac pathologies.

Melanoma immunotherapy using mature DCs expressing the constitutive proteasome.

BACKGROUND: Many cancers, including melanoma, exclusively express constitutive proteasomes (cPs) and are unable to express immunoproteasomes (iPs). In contrast, mature DCs used for immunotherapy exclusively express iPs. Since proteasomes generate peptides presented by HLA class I molecules, we hypothesized that mature melanoma antigen-loaded DCs engineered to process antigens through cPs would be superior inducers of antimelanoma immunity in vivo. METHODS: Subjects with metastatic melanoma were vaccinated with mature DCs transfected with RNAs encoding melanoma antigens MART1, MAGE-3, gp100, and tyrosinase. These DCs were derived from monocytes that were untransfected (Arm A; n = 4), transfected with control siRNA (Arm B; n = 3), or transfected with siRNAs targeting the 3 inducible iP subunits (Arm C; n = 5). RESULTS: Vaccination stimulated antigen-specific T cell responses in all subjects, which peaked after 3-4 vaccinations, but remained elevated in Arm C subjects. Also in Arm C, circulating melanoma cell levels (as detected by quantitative PCR) fell, and T cell lytic activity against autologous melanoma was induced. In HLA-A2⁺ subjects, CD8⁺ T cells that bound tetramers loaded with cP-derived melanoma antigenic peptides were found in the peripheral blood only in Arm C subjects. Of 2 subjects with active disease (both in Arm C), one had a partial clinical response, while the other, who exhibited diffuse dermal and soft tissue metastases, had a complete response. CONCLUSION: These results suggest that the efficacy of melanoma DC-based immunotherapy is enhanced when tumor antigen-loaded DCs used for vaccination express cPs. TRIAL REGISTRATION: Clinicaltrials.gov NCT00672542. FUNDING: Duke Clinical Research Institute/Duke Translational Medicine Institute, Duke Melanoma Consortium, and Duke University Department of Surgery.

Scleroderma and IgG4-related disease.

IgG4-related disease is a syndrome which involves lymphoplasmacytic infiltrates and soft tissue sclerosis, elevated serum IgG4 titer, and increased IgG4-positive plasma cells in a variety of tissues. Scleroderma is also characterized by fibrosis and lymphoplasmacytic infiltrates. To our knowledge, the presence of IgG4-positive cells has not been well characterized in scleroderma. A retrospective review of scleroderma and related disorders (calcinosis, raynaud's syndrome, esophageal dysmotility, sclerodactyly, telangiectasia (CREST) syndrome, progressive systemic sclerosis, morphea) was performed. Thirty-four cases of scleroderma and related disorders were identified; IgG4-positive and IgG-positive plasma cells were counted in 10 HPF and an IgG4:IgG ratio determined. A cutoff ratio of 0.3 was used to define significant elevation. Three of the scleroderma cases had IgG4:IgG greater than 0. Only 1 case had a significant elevation. Of the 3 cases with elevated ratio, IgG4-positive cells ranged from 2 to 64 (median = 14), with an IgG4:IgG ranging from 0.06 to 0.34 (median = 0.22). Similar results were produced with the other sclerosing disorders. These results suggest that scleroderma is not part of the IgG4-related disease spectrum.

Diagnostic and clinical considerations in concomitant bone marrow involvement by plasma cell myeloma and chronic lymphocytic leukemia/monoclonal B-cell lymphocytosis: a series of 15 cases and review of literature.

CONTEXT: Plasma cell myeloma and chronic lymphocytic leukemia are both common hematologic malignancies, sharing many epidemiologic features. Concomitant detection of the 2 conditions poses special diagnostic challenges for the pathologist. OBJECTIVE: To describe the pathologic findings in cases of concomitant bone marrow involvement by myeloma and CD5(+) monoclonal B cells and to outline the differential diagnostic possibilities, suggest a workup for correct diagnosis, and examine clinical outcome. DESIGN: Fifteen cases that met the diagnostic criteria were identified from pathology databases at 4 participating institutions. Morphologic findings were reviewed, additional immunohistochemical stains performed, and flow cytometric, cytogenetic, and relevant laboratory and clinical information was summarized. Previously published cases were searched from electronic databases and cross-references. RESULTS: Most patients (13 of 15) were older males. Often (11 of 15) they presented clinically with myeloma, yet had both monotypic plasma cells and B cells in the diagnostic marrow. In 4 patients, myeloma developed 24 months or later after chronic lymphocytic leukemia. In 7 patients, myeloma and CD5(+) B cells showed identical immunoglobulin light-chain restriction. Primary differential diagnoses include lymphoplasmacytic lymphoma, marginal zone lymphoma, and chronic lymphocytic leukemia with plasmacytoid differentiation. CD56 and/or cyclin D1 expression by plasma cells was helpful for correct diagnosis. Most patients in our cohort and published reports were treated for plasma cell myeloma. CONCLUSIONS: Concomitant detection of myeloma and chronic lymphocytic leukemia in the bone marrow is a rare event, which must be carefully differentiated from lymphomas with lymphoplasmacytic differentiation for correct treatment.

p40 (ΔNp63) and keratin 34ßE12 provide greater diagnostic accuracy than p63 in the evaluation of small cell lung carcinoma in small biopsy samples.

The use of p63 has been advocated for separating small cell lung carcinoma from poorly differentiated non-small cell lung carcinoma, in particular, squamous cell lung carcinoma. However, p63 is not entirely specific in this distinction, as several studies have demonstrated p63 immunoreactivity in a proportion of small cell lung carcinomas. p40 (ΔNp63) has recently been purported to be a highly specific marker for squamous cell lung carcinoma, but data regarding p40 (ΔNp63) in small cell lung carcinoma, a key differential diagnostic consideration in biopsy samples of squamous cell lung carcinoma, are lacking. In this study, a total of 34 previously confirmed small cell lung carcinomas (27 bronchoscopic biopsy samples and 7 large specimens) were immunostained for p40 (ΔNp63), p63, and keratin 34ßE12. All 34 small cell lung carcinomas were negative for p40 (ΔNp63) and keratin 34ßE12. Although none of the large small cell lung carcinoma specimens exhibited p63 immunoreactivity, 12 (44.4%) of 27 biopsy samples of small cell lung carcinoma were positive for p63. The rate of p63 staining in small cell lung carcinoma biopsy samples differed significantly from that of p40 (ΔNp63) and keratin 34ßE12 (P = .005). Ten cases of squamous cell lung carcinoma were also tested, all of which were positive for all 3 markers. These findings confirm that p63 immunoexpression is not uncommon in biopsy samples of small cell lung carcinoma. Positive p63 staining may be mistakenly interpreted as supportive of squamous differentiation and result in misclassification of small cell lung carcinoma as squamous cell lung carcinoma, a diagnostic error that has important therapeutic and prognostic consequences. To provide greater diagnostic accuracy, p40 (ΔNp63) or keratin 34ßE12 should be used instead of p63 in the distinction of small cell lung carcinoma from non-small cell lung carcinoma in biopsy samples.

Follicular lymphoma with prominent Dutcher body formation: a pathologic study of 3 cases in comparison with nodal or splenic lymphoplasmacytic lymphoma and marginal zone lymphoma.

Dutcher bodies have been described in lymphoid neoplasms with plasmacytic differentiation, including plasma cell myeloma, lymphoplasmacytic lymphoma, and marginal zone lymphoma. We report a pathologic study of 3 cases of follicular lymphoma with extensive Dutcher body formation in comparison with lymphoplasmacytic lymphoma and marginal zone lymphoma. Of 3 cases, 1 showed a follicular growth pattern, whereas the other 2 cases demonstrated only a vague nodular appearance highlighted by immunohistochemical analysis. Cells containing Dutcher bodies were counted at 25, 90, or 110 per high-power field in each case, respectively. In 2 cases, cells with Dutcher bodies were clustered in an intrafollicular distribution, a possible histopathologic clue for follicular lymphoma. Immunoglobulin M κ was identified as the component of Dutcher bodies in all 3 cases, implying a possible molecular basis for the formation of Dutcher bodies in B-cell lymphomas. All 3 cases had cytogenetic changes supporting the diagnosis of follicular lymphoma, including dual rearrangement of BCL2 and BCL6, rearrangement of BCL2 with trisomy 3 (BCL6), and isolated BCL6 rearrangement. We emphasize immunohistochemical analyses with anti-κ/λ and anti-immunoglobulin heavy-chain isotypes to characterize Dutcher bodies and document clonality in addition to the routine lymphoma workup and indicated cytogenetic studies in B-cell lymphomas with prominent Dutcher bodies.

A novel role for type 1 angiotensin receptors on T lymphocytes to limit target organ damage in hypertension.

RATIONALE: Human clinical trials using type 1 angiotensin (AT(1)) receptor antagonists indicate that angiotensin II is a critical mediator of cardiovascular and renal disease. However, recent studies have suggested that individual tissue pools of AT(1) receptors may have divergent effects on target organ damage in hypertension. OBJECTIVE: We examined the role of AT(1) receptors on T lymphocytes in the pathogenesis of hypertension and its complications. METHODS AND RESULTS: Deficiency of AT(1) receptors on T cells potentiated kidney injury during hypertension with exaggerated renal expression of chemokines and enhanced accumulation of T cells in the kidney. Kidneys and purified CD4(+) T cells from "T cell knockout" mice lacking AT(1) receptors on T lymphocytes had augmented expression of Th1-associated cytokines including interferon-γ and tumor necrosis factor-α. Within T lymphocytes, the transcription factors T-bet and GATA-3 promote differentiation toward the Th1 and Th2 lineages, respectively, and AT(1) receptor-deficient CD4(+) T cells had enhanced T-bet/GATA-3 expression ratios favoring induction of the Th1 response. Inversely, mice that were unable to mount a Th1 response due to T-bet deficiency were protected from kidney injury in our hypertension model. CONCLUSIONS: The current studies identify an unexpected role for AT(1) receptors on T lymphocytes to protect the kidney in the setting of hypertension by favorably modulating CD4(+) T helper cell differentiation.

Hedgehog pathway activation parallels histologic severity of injury and fibrosis in human nonalcoholic fatty liver disease.

UNLABELLED: The Hedgehog (HH)-signaling pathway mediates several processes that are deregulated in patients with metabolic syndrome (e.g., fat mass regulation, vascular/endothelial remodeling, liver injury and repair, and carcinogenesis). The severity of nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome generally correlate. Therefore, we hypothesized that the level of HH-pathway activation would increase in parallel with the severity of liver damage in NAFLD. To assess potential correlations between known histologic and clinical predictors of advanced liver disease and HH-pathway activation, immunohistochemistry was performed on liver biopsies from a large, well-characterized cohort of NAFLD patients (n = 90) enrolled in the Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN) Database 1 study. Increased HH activity (evidenced by accumulation of HH-ligand-producing cells and HH-responsive target cells) strongly correlated with portal inflammation, ballooning, and fibrosis stage (each P < 0.0001), supporting a relationship between HH-pathway activation and liver damage. Pathway activity also correlated significantly with markers of liver repair, including numbers of hepatic progenitors and myofibroblastic cells (both P < 0.03). In addition, various clinical parameters that have been linked to histologically advanced NAFLD, including increased patient age (P < 0.005), body mass index (P < 0.002), waist circumference (P < 0.0007), homeostatic model assessment of insulin resistance (P < 0.0001), and hypertension (P < 0.02), correlated with hepatic HH activity. CONCLUSION: In NAFLD patients, the level of hepatic HH-pathway activity is highly correlated with the severity of liver damage and with metabolic syndrome parameters that are known to be predictive of advanced liver disease. Hence, deregulation of the HH-signaling network may contribute to the pathogenesis and sequelae of liver damage that develops with metabolic syndrome.

Costaining for keratins 8/18 plus ubiquitin improves detection of hepatocyte injury in nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease is a global health dilemma. The gold standard for diagnosis is liver biopsy. Ballooned hepatocytes are histologic manifestations of hepatocellular injury and are characteristic of steatohepatitis, the more severe form of nonalcoholic fatty liver disease. Definitive histologic identification of ballooned hepatocytes on routine stains, however, can be difficult. Immunohistochemical evidence for loss of the normal hepatocytic keratin 8/18 can serve as an objective marker of ballooned hepatocytes. We sought to explore the utility of a keratin 8/18 plus ubiquitin double immunohistochemical stain for the histologic evaluation of adult nonalcoholic fatty liver disease. Double immunohistochemical staining for keratin 8/18 and ubiquitin was analyzed using 40 adult human nonalcoholic fatty liver disease core liver biopsies. Ballooned hepatocytes lack keratin 8/18 staining as previously shown by others, but normal-size hepatocytes with keratin loss are approximately 5 times greater in number than keratin-negative ballooned hepatocytes. Keratin-negative ballooned hepatocytes, normal-size hepatocytes with keratin loss, and ubiquitin deposits show a zonal distribution, are positively associated with each other, and are frequently found adjacent to or intermixed with fibrous matrix. All 3 lesions correlate with fibrosis stage and the hematoxylin and eosin diagnosis of steatohepatitis (all P < .05). Compared with hematoxylin and eosin staining, immunohistochemical staining improves the receiver operating characteristics curve for advanced fibrosis (0.77 versus 0.83, 0.89, and 0.89 for keratin-negative ballooned hepatocytes, normal-size hepatocytes with keratin loss, and ubiquitin, respectively) because immunohistochemistry is more sensitive and specific for fibrogenic hepatocellular injury than hematoxylin and eosin staining. Keratin 8/18 plus ubiquitin double immunohistochemical stain improves detection of hepatocyte injury in nonalcoholic fatty liver disease. Thus, it may help differentiate nonalcoholic steatohepatitis from nonalcoholic fatty liver.

Molecular detection of circulating Sezary cells in patients with mycosis fungoides: could it predict future development of secondary Sezary syndrome? A single-institution experience.

While the majority of patients with early-stage mycosis fungoides (MF) have an excellent prognosis, a few cases progress to secondary Sezary syndrome (sSS), which carries a dismal clinical outcome. We retrospectively analyzed 135 cases of MF/SS and correlated molecular detection of T-cell clones in the skin and blood with other clinicopathologic findings. When stratified by the diagnoses, patients with MF demonstrated a 26.5% (31/117) positive rate for a blood T-cell clone, of which 50% (10/20) had an identical T-cell clone in the skin. Follow-up evaluation showed conversion into sSS or leukemic phase in 50% (5/10) of cases with a positive blood T-cell clone (estimated mean interval 41.8 months) in comparison to no cases in the group without a clone (0/31). Interestingly, 4/5 cases of sSS had an identical T-cell clone in the skin, while the remaining case did not have the test performed on skin for clonal comparison. Kaplan-Meier survival analysis demonstrated a poor clinical outcome in the group with a blood T-cell clone, in comparison with the group without, in overall survival (p < 0.0001) and progression-free survival (p < 0.0001; HR = 22.6). These findings suggest that molecular detection of a blood T-cell clone may have a role in predicting sSS. Due to amplification of non-neoplastic T-cell expansion in a significant number of cases, comparison of blood T-cell clones with skin may have confirmatory value.

Changes in oligosaccharide chains of autoantibodies to GRP78 expressed during progression of malignant melanoma stimulate melanoma cell growth and survival.

A correlation between expression of the glucose-regulated protein of 78 kDa (GRP78) in malignant melanoma tumors and poor patient survival is well established. In this study, in addition to demonstrating the expression of GRP78 in tumor tissue, we investigated the immune response against GRP78 in a group of patients with different progression stages of malignant melanoma. Furthermore, we analyzed the glycosylation status of GRP78 immunoglobulin (Ig) G autoantibodies at these stages and evaluated their capacities to affect the protein B-dependent protein kinase signaling pathway and unfolded protein response signaling mechanisms, all known to promote malignant melanoma cell proliferation and survival. We found that progression of disease correlates not only with enhanced expression of GRP78 in the tumor but also with an increase in GRP78 autoantibody serum titers in these patients. We also found that the glycosylation status of anti-GRP78 IgG changes as the disease progresses. The anti-GRP78 IgG is abnormally glycosylated in the Fc region and asymmetrically glycosylated in the Fab region. We demonstrate that hyperglycosylated anti-GRP78 IgGs stimulate cell proliferation through protein B-dependent protein kinase signaling pathways. They also mimic the effects of α2-macroglobulin on the upregulation of GRP78 and X-box binding protein 1, activating transcription factor 6 α, and serine/threonine-protein kinase/endoribonuclease precursor α as endoplasmic reticulum stress biomarkers and show no effect on expression or activation of caspases 3, 9, or 12. In conclusion, the anti-GRP78 IgG autoantibodies downregulate apoptosis and activate unfolded protein response mechanisms, which are essential to promote melanoma cell growth and survival.

Increased production of sonic hedgehog by ballooned hepatocytes.

Ballooned hepatocytes distinguish non-alcoholic steatohepatitis (NASH) from steatosis. Such cells contain dilated endoplasmic reticulum and ubiquitin aggregates, characteristics of endoplasmic reticulum stress. Hepatocyte ballooning increases the risk for fibrosis in NASH, suggesting that ballooned hepatocytes release pro-fibrogenic factors. Hedgehog ligands function as pro-fibrogenic factors in liver diseases, but mechanisms for hedgehog ligand production remain poorly understood. We evaluated the hypothesis that endoplasmic reticulum stress induces hepatocyte production of hedgehog ligands that provide paracrine pro-fibrogenic signals to neighbouring cells. In livers from NASH patients, keratin 8/18 and ubiquitin staining demonstrated enlarged, keratin 8/18-negative/ubiquitin-positive hepatocytes (ballooned hepatocytes) that were positive for Sonic hedgehog. In order to model endoplasmic reticulum stress in vitro, primary mouse hepatocytes were treated with tunicamycin. Compared to vehicle, tunicamycin significantly increased Sonic hedgehog and Indian hedgehog expression. Furthermore, conditioned medium from tunicamycin-treated hepatocytes increased Gli-luciferase reporter activity 14-fold more than conditioned medium from vehicle-treated hepatocytes. Cyclopamine (hedgehog signalling inhibitor) abrogated the effect of conditioned medium from tunicamycin-treated hepatocytes, verifying that soluble hepatocyte-derived factors activate hedgehog signalling. Ballooned hepatocytes in NASH patients did not express the hedgehog target gene, Gli2, α-smooth muscle actin or vimentin, but were surrounded by Gli2-positive stromal cells expressing these myofibroblast markers. Trichrome staining demonstrated the accumulation of ballooned hepatocytes in areas of matrix deposition, and numbers of Sonic hedgehog-positive hepatocytes correlated with the degree of ballooning and fibrosis stage. Hepatocytes undergoing endoplasmic reticiulum stress generate hedgehog ligands which act as paracrine pro-fibrogenic factors for hedgehog-responsive stromal cells. These results help to explain why fibrosis stage correlates with hepatocyte ballooning in NASH.

Nuclear Snail1 and nuclear ZEB1 protein expression in invasive and intraductal human breast carcinomas.

Snail1 and ZEB1 are transcriptional repressors that drive tumor initiation and metastasis in animal models. Snail1 and ZEB1 are frequently coexpressed in tumor cell lines, suggesting that these factors may cooperate to promote tumor progression. However, coexpression of these transcriptional repressors in primary human cancer specimens has not been investigated. Previous studies assessed expression in primary breast cancers of Snail1 messenger RNA, which does not reflect Snail1 activity because Snail1 is subject to posttranslational modifications that inhibit its nuclear localization/activity. In the current study, using breast tumor cell lines of known Snail1 and ZEB1 expression status, we developed immunohistochemistry protocols for detecting nuclear Snail1 and nuclear ZEB1 proteins. Using these protocols, we assessed nuclear Snail1 and nuclear ZEB1 expressions in primary human breast cancers of varying subtypes (n = 78). Nuclear Snail1 and estrogen receptor α expressions were inversely associated in primary breast cancers, and nuclear Snail1 was expressed in approximately 80% of triple-negative breast cancers (lacking estrogen receptor α, progesterone receptor, and human epidermal growth factor receptor 2 overexpression). In contrast, nuclear ZEB1 was expressed at a significantly lower frequency in these breast cancers. Notably, nuclear Snail1 protein was detected in 45% of ductal carcinoma in situ specimens (n = 29), raising the important possibility that nuclear Snail1 expression in early stage breast lesions may predict future development of invasive breast cancer. Collectively, our studies demonstrate frequent expression of nuclear Snail1, but not nuclear ZEB1, in invasive, triple-negative breast cancers as well as in intraductal carcinomas.

Cell-cell adhesion proteins in melanocytic pilomatrix carcinoma.

Tumors of the matrix of rigid structures include matrical tumors of the hairs, nails, and teeth. These tumors share similar phenotypical and signaling features. Although benign matrical hair tumors are among the most common of these tumors, hair matrix tumors containing pigmented melanocytes are very rare. The malignant variant called melanocytic pilomatrix carcinoma contains benign colonizing dendritic melanocytes admixed with the carcinomatous follicular matrical cells.We studied the expression of cadherins and ß-catenin in melanocytic pilomatrix carcinoma because cadherin/catenin-dependent cell-cell adhesion and signals play a critical role in the development of hair and hair tumors. We examined the expression of E- and P-cadherin and the multifunctional protein ß-catenin in two cases of melanocytic pilomatrix carcinoma by immunohistochemistry. E- and P-cadherin are expressed at the cell membrane. In contrast, ß-catenin is distributed uniformly in the nucleus and cytoplasm of all tumor cells. The diffuse nuclear and cytoplasmic ß-catenin expression found in melanocytic pilomatrix carcinomas is indicative of transcriptional activation and ß-catenin-induced cell transformation.This is the first report of cadherin/catenin expression in melanocytic pilomatrix carcinoma. Although the study is limited by the number of these rare tumors, the data add information for the understanding of disease mechanisms in hair matrical tumors. Matrical tumors of the hairs share phenotypical features with other matrical tumors and show nuclear translocation of ß-catenin, suggesting a transcriptional activating rather than a cellcell adhesion function.

Acquired vulvar lymphangioma circumscriptum: a comparison of 12 cases with Crohn's associated lesions or radiation therapy induced tumors.

BACKGROUND: Lymphangioma circumscriptum (LC) is a benign lesion of lymphatic origin. Vulvar involvement occurs in various clinical settings. METHODS: We present 12 cases, and compare lesions in patients with Crohn's disease and those associated with pelvic radiation. RESULTS: The average age at presentation was 49 years. Thirty-three percent of the patients had Crohn's disease, 58% had radiation therapy and 9% had no significant medical history. Sixty-seven percent of the patients had multifocal lesions in anatomically distinct regions. Patients presented on average 16 years after onset of predisposing factors. Presenting complaints were pruritus, wetness and vulvar edema. Lesions were clinically heterogeneous, often found on the labia majora. Lesions consisted of dilated lymphatic channels at the junction of the reticular and papillary dermis. The cells lining these spaces lacked cytologic atypicality or mitotic activity. All lesions so examined were immunoreactive for D240. Patients were most often treated with surgical excision followed by laser ablation. Four of twelve patients, all with radiation-associated lesions, experienced disease progression necessitating additional surgery. CONCLUSIONS: Patients with LC secondary to radiation, when compared to those with Crohn's disease, were 10 years younger, more likely to have associated co-morbidities, and frequently experienced disease progression needing additional surgeries. Acquired vulvar LC has multiple causes with differing prognosis.