Role of MIF1/MIF2/CD74 interactions in bladder cancer.

Macrophage migration inhibitory factor (MIF1) is a pleiotropic cytokine involved in inflammation and cancer. Genetic knockout of Mif1 in the validated N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) model of bladder cancer (BCa) resulted in stage arrest at non-muscle-invasive disease in prior studies. Small-molecule inhibition of MIF1 reduced cancer-associated outcomes, but it did not fully recapitulate genetic models. D-dopachrome tautomerase (gene symbol DDT), commonly referred to as MIF2, is a functional homolog of MIF1, and both MIF1 and MIF2 can bind the cell surface receptor CD74 on multiple cell types to initiate a signaling cascade. It has been proposed that this interaction mediates part of the protumorigenic effects of MIF1 and MIF2 and may explain the discordance in prior studies. We hypothesized that MIF2 functions redundantly with MIF1 in BCa development and progression. The Cancer Genome Atlas (TCGA) analysis indicated MIF and DDT expression were increased in BCa patients compared to control. 4-Iodopyridine (4-IPP), a combined MIF1/MIF2 inhibitor, was more efficacious than ISO-1, a MIF1-only inhibitor, in preventing cellular proliferation in BCa cell lines. To evaluate these findings in vivo, wild-type (WT) and Mif1-/- animals were exposed to 0.05% BBN in drinking water for 16 weeks to initiate tumorigenesis and then evaluated over the subsequent 4 weeks for tumor formation and progression in the presence or absence of 4-IPP. 4-IPP reduced bladder weights in WT animals and bladder weights/tumor stage in Mif1-/- animals. To determine whether MIF1/MIF2 functioned through CD74 in BCa, WT or Cd74-/- animals were used in the same BBN model. Although these animals were partially protected against BBN-induced BCa, 4-IPP did not enhance this effect. In conclusion, our data suggest that MIF2 mechanistically functions in a similar protumorigenic manner to MIF1, and this is at least partially through CD74. Dual inhibition of MIF homologs is more efficacious at reducing tumor burden in this model of BCa. © 2022 The Pathological Society of Great Britain and Ireland.

IFT-A deficiency in juvenile mice impairs biliary development and exacerbates ADPKD liver disease.

Polycystic liver disease (PLD) is characterized by the growth of numerous biliary cysts and presents in patients with autosomal dominant polycystic kidney disease (ADPKD), causing significant morbidity. Interestingly, deletion of intraflagellar transport-B (IFT-B) complex genes in adult mouse models of ADPKD attenuates the severity of PKD and PLD. Here we examine the role of deletion of an IFT-A gene, Thm1, in PLD of juvenile and adult Pkd2 conditional knockout mice. Perinatal deletion of Thm1 resulted in disorganized and expanded biliary regions, biliary fibrosis, increased serum bile acids, and a shortened primary cilium on cytokeratin 19+ (CK19+) epithelial cells. In contrast, perinatal deletion of Pkd2 caused PLD, with multiple CK19+ epithelial cell-lined cysts, fibrosis, lengthened primary cilia, and increased Notch and ERK signaling. Perinatal deletion of Thm1 in Pkd2 conditional knockout mice increased hepatomegaly, liver necrosis, as well as serum bilirubin and bile acid levels, indicating enhanced liver disease severity. In contrast to effects in the developing liver, deletion of Thm1 alone in adult mice did not cause a biliary phenotype. Combined deletion of Pkd2 and Thm1 caused variable hepatic cystogenesis at 4 months of age, but differences in hepatic cystogenesis between Pkd2- and Pkd2;Thm1 knockout mice were not observed by 6 months of age. Similar to juvenile PLD, Notch and ERK signaling were increased in adult Pkd2 conditional knockout cyst-lining epithelial cells. Taken together, Thm1 is required for biliary tract development, and proper biliary development restricts PLD severity. Unlike IFT-B genes, Thm1 does not markedly attenuate hepatic cystogenesis, suggesting differences in regulation of signaling and cystogenic processes in the liver by IFT-B and -A. Notably, increased Notch signaling in cyst-lining epithelial cells may indicate that aberrant activation of this pathway promotes hepatic cystogenesis, presenting as a novel potential therapeutic target. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

The utility of immunohistochemical testing for mismatch repair proteins in fine needle aspiration specimens of pancreatic adenocarcinoma.

INTRODUCTION: Microsatellite instability (MSI) testing is recommended for all colonic and endometrial carcinomas to screen for Lynch syndrome. The role of MSI testing in pancreatic adenocarcinoma has not been well-established. Screening can be done via immunohistochemical (IHC) staining for mismatch repair (MMR) proteins (MLH1, MSH2, MSH6, PMS2). We report our experience and the clinical utility of MMR IHC on pancreatic adenocarcinomas in fine-needle aspiration (FNA) specimens. MATERIALS AND METHODS: We performed a retrospective review to identify all patients diagnosed with pancreatic adenocarcinoma by FNA at our institution between December 2017 and September 2019. For cases with sufficient tumor cells for testing, the MMR results and morphology were summarized, as well as corresponding clinical information, including age, clinical stage, treatment, and concurrent other cancers. RESULTS: From December 2017 to September 2019, there were a total of 184 pancreatic FNAs with a diagnosis of adenocarcinoma. Of these 184 FNAs, 65 (35%) contained sufficient material in the cell block to perform IHC for MMR. The cell block material was collected in either RPMI or CytoLyt. Poor technical quality precluded interpretation of PMS2 in 4 cases and MSH6 in 2 cases. All other cases showed intact expression of all four proteins. CONCLUSIONS: IHC for MMR proteins can be done on specimens collected in RPMI or CytoLyt, but RPMI appears to be more reliable. None of the pancreatic adenocarcinomas in this study showed loss of MMR protein expression. Routine testing of MMR loss may not be indicated in pancreatic adenocarcinomas in the general patient population.

Suboptimal Agreement Among Cytopathologists in Diagnosis of Malignancy Based on Endoscopic Ultrasound Needle Aspirates of Solid Pancreatic Lesions: A Validation Study.

BACKGROUND & AIMS: Despite the widespread use of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to sample pancreatic lesions and the standardization of pancreaticobiliary cytopathologic nomenclature, there are few data on inter-observer agreement among cytopathologists evaluating pancreatic cytologic specimens obtained by EUS-FNA. We developed a scoring system to assess agreement among cytopathologists in overall diagnosis and quantitative and qualitative parameters, and evaluated factors associated with agreement. METHODS: We performed a prospective study to validate results from our pilot study that demonstrated moderate to substantial inter-observer agreement among cytopathologists for the final cytologic diagnosis. In the first phase, 3 cytopathologists refined criteria for assessment of quantity and quality measures. During phase 2, EUS-FNA specimens of solid pancreatic lesions from 46 patients were evaluated by 11 cytopathologists at 5 tertiary care centers using a standardized scoring tool. Individual quantitative and qualitative measures were scored and an overall cytologic diagnosis was determined. Clinical and EUS parameters were assessed as predictors of unanimous agreement. Inter-observer agreement (IOA) was calculated using multi-rater kappa (κ) statistics and a logistic regression model was created to identify factors associated with unanimous agreement. RESULTS: The IOA for final diagnoses, based on cytologic analysis, was moderate (κ = 0.56; 95% CI, 0.43-0.70). Kappa values did not increase when categories of suspicious for malignancy, malignant, and neoplasm were combined. IOA was slight to moderate for individual quantitative (κ = 0.007; 95% CI, -0.03 to -0.04) and qualitative parameters (κ = 0.5; 95% CI, 0.47-0.53). Jaundice was the only factor associated with agreement among all cytopathologists on multivariate analysis (odds ratio for unanimous agreement, 5.3; 95% CI, 1.1-26.89). CONCLUSIONS: There is a suboptimal level of agreement among cytopathologists in the diagnosis of malignancy based on analysis of EUS-FNA specimens obtained from solid pancreatic masses. Strategies are needed to refine the cytologic criteria for diagnosis of malignancy and enhance tissue acquisition techniques to improve diagnostic reproducibility among cytopathologists.

C57BL/6 Substrains Exhibit Different Responses to Acute Carbon Tetrachloride Exposure: Implications for Work Involving Transgenic Mice.

Biological differences exist between strains of laboratory mice, and it is becoming increasingly evident that there are differences between substrains. In the C57BL/6 mouse, the primary substrains are called 6J and 6N. Previous studies have demonstrated that 6J and 6N mice differ in response to many experimental models of human disease. The aim of our study was to determine if differences exist between 6J and 6N mice in terms of their response to acute carbon tetrachloride (CCl4) exposure. Mice were given CCl4 once and were euthanized 12 to 96 h later. Relative to 6J mice, we found that 6N mice had increased liver injury but more rapid repair. This was because of the increased speed with which necrotic hepatocytes were removed in 6N mice and was directly related to increased recruitment of macrophages to the liver. In parallel, enhanced liver regeneration was observed in 6N relative to 6J mice. Hepatic stellate cell activation occurred earlier in 6N mice, but there was no difference in matrix metabolism between substrains. Taken together, these data demonstrate specific and significant differences in how the C57BL/6 substrains respond to acute CCl4, which has important implications for all mouse studies utilizing this model.

Aging induces changes in cancer formation and microbial content in a murine model of bladder cancer.

Bladder cancer (BCa) incidence is tightly linked to aging. Older patients with BCa present with higher grade tumors and have worse outcomes on Bacillus-Calmette-Guerin (BCG) immunotherapy. Aging is also known to result in changes in the gut microbiome over mammalian lifespan, with recent studies linking alterations in the gut microbiome to changes in tumor immunity. There is limited information on the microbiome in BCa models though, despite known links to aging and immunotherapy. The purpose of this study was to evaluate how aging impacts tumor formation, inflammation, and the microbiome of mice given the model BCa carcinogen N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). We hypothesized old animals would have larger, more inflamed tumors and a shift in their fecal microbiome compared to their younger counterparts. Young (~8-week-old) or old (~78-week-old) C57Bl/6J animals were administered 0.05% BBN in drinking water for 16 weeks and then euthanized or allowed to progress for an additional 4 weeks. After 16 weeks of BBN, old mice had higher bladder to body weight ratio than young mice, and also muscle invasive tumors, which were not seen in their young counterparts. Old animals also had increased innate immune recruitment, but CD4+/CD8+ T cell recruitment did not appear different. BBN dramatically altered the microbiome in both sets of animals as measured by ß-diversity, including changes in multiple genera of bacteria. These data suggest old mice have a differential response to BBN-induced BCa. Given the median age of patients with BCa, understanding how the aged phenotype interacts with BCa is imperative.

Splenic nodules at autopsy.

Gamna-Gandy bodies (GGBs), also known as hemosiderotic nodules, were first described in 1921 in association with sickle cell disease. Since then, they have been documented to occur in association with other pathological processes such as hemolytic anemia, congestive splenomegaly, hereditary hemochromatosis; and acquired hemosiderosis. Despite a uniquely characteristic microscopic appearance that is easily recognized by routine histopathologic examination, the precise significance of GGBs remains unknown. As such, documentation of GGBs in patients either by pathology or radiology should herald the presence of a systemic disorder such as sickle cell anemia or hemochromatosis wherein portal hypertension and/or congestive splenomegaly are present. In this article, we briefly present two autopsy cases from two patients with distinctly different clinical presentations wherein classic Gamna-Gandy bodies are illustrated on routine histopathologic examination.

Hyaluronan synthesis inhibition normalizes ethanol-enhanced hepatic stellate cell activation.

BACKGROUND: Chronic ethanol overconsumption promotes alcohol-associated liver disease (ALD), characterized by hepatocyte injury, inflammation, hepatic stellate cell (HSC) activation, and fibrosis. Hyaluronan (HA) concentration is greater in livers and blood from advanced ALD patients than patients with advanced non-ALD. In the liver, HSCs are the major HA producers. The relationship between ethanol, HA, and HSC activation is incompletely understood. Thus, here, we tested the hypothesis that ethanol enhances HSC activation in a HA-dependent manner. METHODS: Liver tissue microarrays (TMAs) containing steatotic livers from donors with or without a history of alcohol consumption were used to measure HA and collagen content. Mice were fed a moderate (2%, v/v) ethanol-containing diet or pair-fed control diet for 2 days, after which they were given a single carbon tetrachloride (CCl4 ) injection. To inhibit HA synthesis, we provided 4-methylumbelliferone (4MU) daily. We used LX2 cells, a human HSC cell line, to determine the impact ethanol had on LPS responses, with or without concurrent 4MU exposure. RESULTS: CCl4 induced liver injury, but it did not differ between ethanol or control diet fed mice with or without 4MU treatment. Ethanol feeding enhanced CCl4 -induced hepatic HA content, which was paralleled by HA synthase (Has)2 transcript abundance; 4MU treatment normalized both. Consistently, HSC activation, assessed by measuring αSMA mRNA and protein, was induced by CCl4 exposure, enhanced by ethanol feeding, and normalized by 4MU. Hepatic transcripts, but not protein, for Ccl2 were enhanced by ethanol feeding and normalized by 4MU exposure. Finally, ethanol-exposed LX2 cells made more LPS-stimulated CCL2 mRNA and protein than cells not exposed to ethanol; 4MU prevented this. CONCLUSION: These data show that ethanol augments HSC activation through HA synthesis and enhances hepatic profibrogenic features. Therefore, targeting HSC HA production could potentially attenuate liver disease in ALD patients.

Pyruvate Dehydrogenase Kinase 4 Deficiency Increases Tumorigenesis in a Murine Model of Bladder Cancer.

Pyruvate dehydrogenase kinase 4 (PDK4) is a mitochondrial isozyme in the PDK family (PDK1-4) partially responsible for phosphorylation of pyruvate dehydrogenase (PDH). Phosphorylation of PDH is thought to result in a pro-proliferative shift in metabolism that sustains growth of cancer cells. Previous data from our lab indicate the pan-PDK inhibitor dichloroacetate (DCA) or acute genetic knockdown of PDK4 blocks proliferation of bladder cancer (BCa) cells. The goal of this study was to determine the role of PDK4 in an in vivo BCa model, with the hypothesis that genetic depletion of PDK4 would impair formation of BCa. PDK4-/- or WT animals were exposed to N-Butyl-N-(4-hydroxybutyl) nitrosamine (BBN) for 16 weeks, and tumors were allowed to develop for up to 7 additional weeks. PDK4-/- mice had significantly larger tumors at later time points. When animals were treated with cisplatin, PDK4-/- animals still had larger tumors than WT mice. PDK4 expression was assessed in human tissue and in mice. WT mice lost expression of PDK4 as tumors became muscle-invasive. Similar results were observed in human samples, wherein tumors had less expression of PDK4 than benign tissue. In summary, PDK4 has a complex, multifunctional role in BCa and may represent an underrecognized tumor suppressor.

Impact of Biopsy Proven Liver Fibrosis on Patients Undergoing Evaluation and Treatment for Advanced Heart Failure Surgical Therapies.

There is a paucity of data regarding the impact of liver fibrosis on patients with stage D heart failure (HF). We conducted a retrospective study (January 1, 2017 to December 12, 2020) in patients with stage D HF who underwent liver biopsy as part of their advanced HF therapy evaluation. Baseline characteristics and 1-year outcomes were compared between no- or mild-to-moderate-fibrosis (grade 0 to 2) and advanced-fibrosis (grade 3 to 4) groups. Of 519 patients with stage D HF, 136 who underwent liver biopsy (113 [83%] no or mild-to-moderate fibrosis and 23 [17%] advanced fibrosis) were included. A total of 71 patients (52%) received advanced HF therapies (23 heart transplantation, 48 left ventricular assist devices). One-year mortality was higher among patients with advanced fibrosis (52% vs 18%, p <0.001). Further subgroup analysis suggested a trend toward increased 1-year mortality among patients with advanced fibrosis who underwent advanced therapies (37% vs 13%, p = 0.09). There was a trend of lower likelihood of receiving advanced HF therapies in the advanced-fibrosis group, only 1 heart transplantation and 7 left ventricular assist devices, but it did not reach statistical significance (35% vs 56%, p = 0.06). After adjustment for confounders, degree of liver fibrosis was an independent predictor of mortality (odds ratio 6.2; 95% 1.27 to 30.29, p = 0.02). We conclude that advanced liver fibrosis is common among patients with stage D HF who undergo evaluation for advanced HF surgical therapies and significantly increases 1-year mortality. Further larger studies are needed to support our findings.

A prospective, single-blind, randomized, controlled trial of EUS-guided FNA with and without a stylet.

BACKGROUND: Most endosonographers use an EUS needle with an internal stylet during EUS-guided FNA (EUS-FNA). Reinserting the stylet into the needle after every pass is tedious and time-consuming, and there are no data to suggest that it improves the quality of the cytology specimen. OBJECTIVE: To compare the samples obtained by EUS-FNA with and without a stylet for (1) the degree of cellularity, adequacy, contamination, and amount of blood and (2) the diagnostic yield of malignancy. DESIGN: Prospective,single-blind, randomized, controlled trial. SETTING: Two tertiary care referral centers. PATIENTS: Patients referred for EUS-FNA of solid lesions. INTERVENTION: Patients underwent EUS-FNA of the solid lesions, and 2 passes each were made with a stylet and without a stylet in the needle. The order of the passes was randomized, and the cytopathologists reviewing the slides were blinded to the stylet status of passes. MAIN OUTCOME MEASUREMENTS: Degree of cellularity, adequacy, contamination, amount of blood, and the diagnostic yield of malignancy in the specimens. RESULTS: A total of 101 patients with 118 lesions were included in final analysis; 236 FNA passes were made, each with and without a stylet. No significant differences were seen in the cellularity (P = .98), adequacy of the specimen (P = .26), contamination (P = .92), or significant amount of blood (P = .61) between specimens obtained with and without a stylet. The diagnostic yield of malignancy was 55 of 236 specimens (23%) in the with-stylet group compared with 66 of 236 specimens (28%) in the without-stylet group (P = .29). LIMITATIONS: Endosonographers were not blinded to the stylet status of the passes. CONCLUSIONS: Using a stylet during EUS-FNA does not confer any significant advantage with regard to the quality of the specimen obtained or the diagnostic yield of malignancy. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT 01213290).

Experience-dependent recovery of vision following chronic deprivation amblyopia.

The shift in ocular dominance induced by brief monocular deprivation is greatest during a postnatal critical period and is thought to decline irreversibly thereafter. However, here we demonstrate that complete visual deprivation through dark exposure restores rapid ocular dominance plasticity in adult rats. In addition, the loss of visual acuity resulting from chronic monocular deprivation is reversed if dark exposure precedes removal of the occlusion in adulthood, suggesting a potential use for dark exposure in the treatment of adult amblyopia.

Cervical Papanicolaou tests in the female-to-male transgender population: should the adequacy criteria be revised in this population? An Institutional Experience.

INTRODUCTION: It is recommended that female-to-male (FTM) transgender patients with a cervix follow the same cervical cancer screening guidelines as cisgender women. This study analyzes Papanicolaou tests, HPV results, and follow-up histology in FTM patients, and compares those results to other atrophic populations at our institution. MATERIALS AND METHODS: A cohort of FTM patients receiving androgen therapy was identified through our institution's translational research database. We collected data on Papanicolaou tests, human papillomavirus (HPV) results, follow-up surgical procedures, and duration of androgen therapy. ThinPrep slides were reviewed for cellularity and cytomorphology. The results of these tests were compared with those of an atrophic control group consisting of postpartum and postmenopausal cisgender women. RESULTS: We identified 71 FTM patients with 77 Papanicolaou tests collected over 6 years. Papanicolaou interpretations included: negative for intraepithelial lesion (69%), atypical cells of undermined significance (5%), low grade squamous intraepithelial lesion (1%), atypical glandular cells (1%), and unsatisfactory due to inadequate cellularity (23%). Five of 27 (18.5%) HPV tests were positive. Follow-up surgical specimens did not identify high-grade lesions. Unsatisfactory rates among FTM patients differed significantly from the atrophic group (P < 0.05), while epithelial abnormality rates and HPV positivity did not (P > 0.05). Most FTM Papanicolaou tests reviewed showed features of atrophy. CONCLUSIONS: FTM patients receiving androgen have high Papanicolaou test unsatisfactory rates secondary to atrophy. Epithelial abnormality and HPV rates do not differ significantly from atrophic cisgender patients. Lowering the cellularity threshold for this population to 2000 like that of other atrophic groups should be considered.

Triaging of pleural effusion cytology specimens for ancillary flow cytometric analysis.

INTRODUCTION: There are no established criteria in selecting pleural effusion (PE) specimens for flow cytometric analysis (FCA). FCA on effusion specimens may be ordered by a clinician or a cytopathologist. In an effort to improve lab test utilization, this retrospective study aims to identify characteristics of PE specimens on which the addition of FCA has high diagnostic yield. MATERIALS AND METHODS: We identified consecutive cases of PE cytology specimens on which FCA was performed over a 5-year period (2014-2019). Patient demographic data and history, FCA diagnosis, cytologic diagnosis, cellular quantity and composition, and peripheral blood cell counts were collected. Chi-square, Mann-Whitney U, and t tests were used when appropriate with a significance level of P < 0.05. RESULTS: We identified 164 FCA cases corresponding to 142 patients (age: 19-90 years; male:female 2:1). The majority of cases had no abnormality by cytologic examination, whereas others were obviously malignant due to non-hematologic malignancy. Most (119 of 164, 73%) had negative immunophenotypic studies by FCA. Forty-five of 164 (27%) FCA cases were positive for a monoclonal myeloid or lymphoid population. Clinicopathologic features associated with positive FCA results included a history of hematologic malignancy, peripheral blood lymphocytes of ≥20%, the presence of a monomorphic lymphoid population, large atypical cells, and mitoses. CONCLUSIONS: This study identifies features that are associated with positive FCA in PE cytology specimens. Using these features by cytopathologists to order FCA on PE specimens as a reflex test would significantly reduce unnecessary testing and improve FCA utilization.

Near-Miss Diagnoses of Solitary Bladder Tumors Highlight the Importance of Immunohistochemical Staining.

We report three cases of prostate adenocarcinoma appearing as bladder masses and misdiagnosed as muscle-invasive bladder cancer (MIBC). Patients were referred for consideration for radical cystectomy after initial pathological diagnosis suggested poorly differentiated bladder cancer. Pathological review of tissue samples and subsequent immunohistochemical (IHC) staining confirmed advanced prostatic adenocarcinoma. Systemic therapy for prostate cancer was then initiated. These cases highlight the importance of patient history, physical exam, and IHC staining in consideration of a bladder mass, as these patients may have been subject to undue morbidity and surgical intervention without accurate pathologic diagnosis.

Effects of short-term finasteride on apoptotic factors and androgen receptors in prostate cancer cells.

PURPOSE: We explored the molecular correlates of the effect of finasteride on prostate tissue in patients undergoing radical prostatectomy. MATERIALS AND METHODS: Patients undergoing radical prostatectomy for localized prostate cancer were eligible for study. After providing informed consent patients were randomized to receive 5 mg finasteride or placebo daily for at least 30 days before surgery. At surgery prostate tissue was harvested from the surgical specimen and sent for analysis. Tissue samples were analyzed for the pro-apoptotic factors caspase-3, caspase-7 and IGFBP-3. Samples were also analyzed for the tumor suppressor/proto-oncoproteins bcl-2, p53 and p21. Finally, tissues were analyzed for androgen receptor density and insulin growth factor-1. RESULTS: A total of 22 study and 20 placebo samples were collected and analyzed. Negligible staining for bcl-2 or caspase-3 was noted in each group. Statistical differences were not observed for bcl-2, p53, p21 or insulin growth factor-1 between the groups. There was a statistically significant difference in caspase-7 and IGFBP-3. A mean of 77% and 99.9% of cells stained for caspase-7 in the treatment and placebo groups, respectively (p = 0.007). In 3 patients caspase-7 staining disappeared completely and it was decreased by 70% and 50% in 1 patient each. Mean intensity staining for IGFBP-3 was 1.03 in the treatment group and 1.54 in the placebo group (p = 0.005). The staining intensity of nuclear androgen receptors on benign and cancerous cells was not significantly different between the treatment and placebo groups. However, there was a significant difference in androgen receptor staining between benign and cancer cells in the 2 populations. Mean nuclear androgen receptor staining intensity in all cancer and all benign tissue samples was 119.3 and 151.8, respectively (0.001). CONCLUSIONS: Finasteride administered 30 days before surgery appears to decrease the apoptotic factors caspase-7 and IGFBP-3 in cancer cells, while having little to no effect on caspase-3, insulin growth factor-1, bcl-2, p53 and p21. This short-term study may have interesting implications for interpreting Prostate Cancer Prevention Trial data on the molecular level. No differences were noted between the treatment and placebo groups in the expression of nuclear androgen receptor. However, decreased expression of androgen receptors was present in cancer cells compared to that in benign prostate cells in the 2 groups.

BRAF V600 Mutational Status in Melanoma Correlates with Cytologic Features in Fine-Needle Aspirate Specimens.

Melanomas are known as the great mimicker and must be considered in the differential diagnosis of any fine-needle aspirations (FNA). Despite recent advancements in understanding of the mutational landscape of melanomas, there still exists a divide between the genetic and morphologic correlates. A consecutive cohort of 39 FNA of clinically verified metastatic melanomas with concurrent BRAF V600 assessment were selected [positive (n = 18) and wild-type (n = 21)]. The melanoma cytology specimens were evaluated blinded to the BRAF mutation status in a dichotomized fashion for the presence of 8 selected morphologic classifiers. When comparing the BRAF-mutated vs. BRAF-wild type cohorts, the percentage of cases were, respectively: macronucleoli (56 and 52%), intranuclear inclusions (50 and 33%), pigment (44 and 24%), binucleation/multinucleation (78 and 57%), nuclear pleomorphism (72 and 67%), cytoplasmic vacuolization (22 and 29%), spindle cell morphology (61 and 29%), and necrosis (11 and 10%). The average age of the BRAF-mutated cohort was 52.2 years, compared to the BRAF wild-type cohort at 65.2 years. The prevalence of sex ratio and the location of the primary melanoma were matched between cohorts. Spindle cell morphology was more correlated with BRAF V600-mutated melanomas. Clinicians utilized the BRAF status to alter clinical decisions with use of BRAF inhibitors.

Not all neck mass fine-needle aspirations with squamous cells are squamous cell carcinoma; report of a case of recurrent thyroid carcinoma with papillary and squamous components.

We report a case of a 65-year-old female who had a total thyroidectomy 12 years ago for papillary thyroid carcinoma (PTC) who presented with a recurrent thyroid bed mass. Fine-needle aspiration biopsy yielded malignant cells, consistent with squamous cell carcinoma (SCCa). Surgical resection was performed, and histologic evaluation of the mass showed mixed PTC and SCCa. The tumor cells were positive for BRAF V600E mutation. Thyroid carcinomas with admixed papillary carcinoma and SCCa are rare and are associated with aggressive behavior, high rates of metastasis, and poor outcomes. Although SCCa presenting as a neck mass is relatively common, clinical history and appropriate workup are essential for accurate diagnosis and determination of origin.

Bile acids regulate cysteine catabolism and glutathione regeneration to modulate hepatic sensitivity to oxidative injury.

Bile acids are signaling molecules that critically control hepatocellular function. Disrupted bile acid homeostasis may be implicated in the pathogenesis of chronic liver diseases. Glutathione is an important antioxidant that protects the liver against oxidative injury. Various forms of liver disease share the common characteristics of reduced cellular glutathione and elevated oxidative stress. This study reports a potentially novel physiological function of bile acids in regulating hepatic sulfur amino acid and glutathione metabolism. We found that bile acids strongly inhibited the cysteine dioxygenase type-1-mediated (CDO1-mediated) cysteine catabolic pathway via a farnesoid X receptor-dependent mechanism. Attenuating this bile acid repressive effect depleted the free cysteine pool and reduced the glutathione concentration in mouse liver. Upon acetaminophen challenge, cholestyramine-fed mice showed impaired hepatic glutathione regeneration capacity and markedly worsened liver injury, which was fully prevented by N-acetylcysteine administration. These effects were recapitulated in CDO1-overexpressing hepatocytes. Findings from this study support the importance of maintaining bile acid homeostasis under physiological and pathophysiological conditions, as altered hepatic bile acid signaling may negatively impact the antioxidant defense mechanism and sensitivity to oxidative injury. Furthermore, this finding provides a possible explanation for the reported mild hepatotoxicity associated with the clinical use of bile acid sequestrants in human patients.

Biclonal post-transplant B-cell lymphoma: report of a case with two distinct cell populations, XX,t(14;18) and XY,t(11;14).

Lymphoproliferative disorders are more likely to occur in transplant patients compared to the general population. Typically in these patients, lymphomas occur within 6-10 months following transplant and are Epstein-Barr virus (EBV) positive. We report a biclonal apparently EBV negative lymphoma occurring in a patient ten years after renal transplant, with karyotypes XX,t(14;18) and XY,t(11;14). Though the biclonal populations also had different sex chromosome compositions, complete evaluation showed that both clones most likely evolved from the patient's native lymphocytes.