The PARsylation activity of tankyrase in adipose tissue modulates systemic glucose metabolism in mice.

AIMS/HYPOTHESIS: Tankyrase (TNKS) is a ubiquitously expressed molecular scaffold that is implicated in diverse processes. The catalytic activity of TNKS modifies substrate proteins through poly-ADP-ribosylation (PARsylation) and is responsive to cellular energetic state. Global deficiency of the TNKS protein in mice accelerates glucose utilisation and raises plasma adiponectin levels. The aim of this study was to investigate whether the PARsylation activity of TNKS in adipocytes plays a role in systemic glucose homeostasis. METHODS: To inhibit TNKS-mediated PARsylation, we fed mice with a diet containing the TNKS-specific inhibitor G007-LK. To genetically inactivate TNKS catalysis in adipocytes while preserving its function as a molecular scaffold, we used an adipocyte-selective Cre transgene to delete TNKS exons that encoded the catalytic domain at the C-terminus. Tissue-specific insulin sensitivity in mice was investigated using hyperinsulinaemic-euglycaemic clamps. To model adipose-liver crosstalk ex vivo, we applied adipocyte-conditioned media to hepatocytes and assessed the effect on gluconeogenesis. RESULTS: The TNKS inhibitor G007-LK improved glucose tolerance and insulin sensitivity and promptly increased plasma adiponectin levels. In female mice, but not in male mice, adipocyte-selective genetic inactivation of TNKS catalysis improved hepatic insulin sensitivity and post-transcriptionally increased plasma adiponectin levels. Both pharmacological and genetic TNKS inhibition in female mouse-derived adipocytes induced a change in secreted factors to decrease gluconeogenesis in primary hepatocytes. CONCLUSIONS/INTERPRETATION: Systemic glucose homeostasis is regulated by the PARsylation activity of TNKS in adipocytes. This regulation is mediated in part by adipocyte-secreted factors that modulate hepatic glucose production. Pharmacological TNKS inhibition could potentially be used to improve glucose tolerance.

Discontinuous unilateral involvement of 12 part core biopsies by adenocarcinoma predicts bilateral involvement of subsequent radical prostatectomy.

At our institution, percent tumor burden in prostate core biopsies is quantified using variations of one of two methods. Measurement by the Aggregate method reports only adenocarcinoma and omits intervening stroma and benign prostatic glands while the Discontinuous method includes the intervening stroma and benign glands between distinct foci of adenocarcinoma. In this study, we selected cases with 12-part core biopsies that were followed by a radical prostatectomy within two years. Interestingly, we found that when adenocarcinoma involved prostate 12-part core biopsies and subsequent resection unilaterally, there is no significant difference in absolute percentage of tumor using either measuring method (P = 0.4). In contrast, when adenocarcinoma involved the biopsies unilaterally and subsequent prostatectomy bilaterally, the two measurement methods had a statistically significant difference in percentage scores (P = 0.002). In the study cohort, other factors including Gleason score (P = 0.88) and total number of adenocarcinoma-involved cores (P = 0.27) did not introduce any significant correlation with bilateral involvement. In this study, we found that biopsies that discontinuously and unilaterally involve half of a prostate are much more likely to involve both lobes than those that are unilateral and present in nodular aggregates.

Lung carcinoma progression and survival versus amino- and carboxyl-parathyroid hormone-related protein expression.

PURPOSE: Expression of the carboxyl PTHrP region of parathyroid hormone-related protein (PTHrP) is a positive prognostic indicator in women with lung cancer, but amino PTHrP is a negative indicator in other lung cancer patients. This project investigated whether PTHrP could be expressed as predominantly amino PTHrP or carboxyl PTHrP in individual lung carcinomas. It also assessed domain-specific effects on cancer progression and patient survival. METHODS: PTHrP immunoreactivities were analyzed versus survival in a human lung cancer tissue microarray (TMA). Growth was compared in athymic mice for isogenic lung carcinoma xenografts differing in expression of amino and carboxyl PTHrP domains. RESULTS: In the TMA, 33 of 99 patient tumors expressed only one PTHrP domain, while 54 expressed both. By Cox regression, the hazard ratio for cancer-specific mortality (95% confidence interval) was 2.6 (1.28-5.44) for amino PTHrP (P = 0.008) and 0.6 (0-2.58) for carboxyl PTHrP (P = 0.092). Xenografts of H358 lung adenocarcinoma cells that overexpressed amino PTHrP grew twice as fast as isogenic low PTHrP tumors in athymic mice, but growth of tumors expressing amino plus carboxyl PTHrP was not significantly different than growth of the control tumors. In summary, the presence of amino PTHrP signifies worse prognosis in lung cancer patients. In mouse xenografts, this effect was abrogated if carboxyl PTHrP was also present. CONCLUSION: Amino PTHrP and carboxyl PTHrP can vary independently in different lung carcinomas. Carboxyl PTHrP may temper the stimulatory effect of amino PTHrP on cancer progression.

A case of intra-articular angioleiomyoma of the talocrural joint.

Angioleiomyoma is a benign pericytic neoplasm with smooth muscle differentiation. Intra-articular angioleiomyoma is exceptionally rare with only four cases reported, all involving the knee joint. Here we report the first case of intra-articular angioleiomyoma entirely localized within the ankle joint. An 83-year-old male presented with progressively worsening ankle pain. Subsequent magnetic resonance imaging showed a soft tissue mass within the talocrural joint. Histologic examination and ancillary testing demonstrated fascicles of smooth muscle cells and interspersed, often compressed, vascular channels, consistent with an angioleiomyoma. This case highlights the importance of including angioleiomyoma in the differential diagnosis of an ankle joint mass.

Visualization of early prostatic adenocarcinoma as a stem cell disease.

Prostate Cancer represents the second leading cause of cancer death among men in the United States, and the third leading cause of cancer death among men in Europe. We have previously shown that cells possessing Cancer Stem Cell (CSC) characteristics can be grown from human PrCa tissue harvested at the time of prostatectomy. However, the cellular origin of these CSCs was not previously known. In most cases, simple hematoxylin and eosin (H&E) stained sections are sufficient to make a definitive diagnosis of prostatic adenocarcinoma (PrCa) in needle biopsy samples. We utilized six different antibodies specific for stem cell antigens to examine paraffin sections of PrCa taken at the time of needle-biopsy diagnosis. These antisera were specific for CD44, CD133, ALDH7A1, LGR-5, Oct-4 and NANOG. We demonstrate specific staining of tumor cells with all six antisera specific for stem cell antigens. Some of these antibodies also react with cells of hyperplastic glands, but the patterns of reactivity differ from those of malignant glands. These findings demonstrate that at the time of diagnosis, PrCa consists of cells exhibiting properties of CSCs and consistent with the possibility that PrCa is a stem cell disease.

EBUS-FNA of a station seven lymph node: an unusual presentation of a young nonsmoker male with hemoptysis and subcarinal lymphadenopathy.

Endobronchial ultrasound-guided fine needle aspiration (EBUS-FNA) is a safe and minimally invasive bronchoscopic technique that allows both visualization and cytologic sampling with a high diagnostic yield in a patient with mediastinal lymphadenopathy. Besides the most common indication of staging for a patient with a primary lung carcinoma, EBUS-FNA can be used to identify benign infectious and noninfectious processes as well as lymphoma and malignancy of unknown primary. Triaging of procured specimen for diagnostic, prognostic, and therapeutic ancillary studies requires appropriate clinical information at the time of rapid on site evaluation (ROSE) of smears. This case report demonstrates a young, previously healthy nonsmoker presenting clinically with cough, hemoptysis, and a 1.7 cm enlarged subcarinal lymph node by imaging. EBUS-FNA obtained smears from the lymph node revealed a pleomorphic population of smaller cells with a low nuclear to cytoplasmic ratio and prominent nucleoli, and larger cells had nuclei with bizarre shapes, mitoses, multinucleation, enlarged nucleoli, and pigmentation in a background of lymphocytes. The cytomorphologic and immunohistochemical workup of this case confirmed the unexpected diagnosis of metastatic melanoma. This result was a complete surprise to the clinical team managing the patient and prompted a thorough clinical workup. Subcarinal lymphadenopathy with metastatic malignant melanoma as the cause is rare. This case report highlights how ROSE and appropriate triaging of specimen were crucial in appropriately working up this case. We also survey the literature to review the reported unusual presentations of metastatic melanoma.

A single institution experience with the new bethesda system for reporting thyroid cytopathology: correlation with existing cytologic, clinical, and histological data.

Our goal was to evaluate the Bethesda system (TBS) in comparison to the previously used system at our institution. One hundred consecutive thyroid fine needle aspirations (FNAs) and 45 consecutive indeterminate FNAs were reviewed by two cytopathology-boarded pathologists, diagnosed based on TBS and correlated with management and follow-up. Re-evaluation led to a diagnosis change in 48% of cases. Thirty-nine percent of benign cases were unsatisfactory under TBS. For malignant diagnoses the positive predictive value (PPV) was unchanged, while the negative predictive value (NPV) was slightly improved using TBS. Both the PPV and NPV were improved for actionable diagnoses. Inter-observer variability across all categories was in moderate agreement. Clinical management of both follicular lesion (FL) and indeterminate cases ranged from none to immediate surgery. Repeat FNA resolved the diagnosis in 50% of indeterminate cases. Indeterminate cases had an overall malignancy rate of 27%; higher in pre- (46%) than post-TBS cases (8%). Inter-observer variability between the reviewing pathologists and the original pathologists for indeterminate cases was fair, and between the two reviewing pathologists was moderate. Using TBS criteria increased the unsatisfactory rate and led to improved prediction of malignancy and actionable diagnoses. The pre-Bethesda diagnosis of FL at our institution led to inconsistent clinical management. Clinical management of patients with indeterminate diagnoses was essentially unchanged following adoption of TBS. The moderate inter-observer agreement between the reviewing pathologists may be related to level of cytology experience, strict adherence to TBS, and the exclusive use of cytomorphology for diagnosis.

Diagnostic value of K-ras mutation analysis for pancreaticobiliary cytology specimens with indeterminate diagnosis.

BACKGROUND: Fine-needle aspiration and bile duct brushing cytology have been traditionally used for early detection of pancreaticobiliary malignancy. Quite frequently, the cytological interpretations of these specimens are indeterminate. In this retrospective study, we evaluated the diagnostic value of detecting K-ras (v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog) mutation in pancreaticobiliary cytology specimens that had equivocal cytological diagnoses. METHODS: A total of 129 cases that had indeterminate cytology diagnoses, K-ras mutational analysis, and histopathological follow-up were retrieved. The cytological interpretations, histopathological diagnoses, and K-ras mutation results were reviewed and analyzed. RESULTS: Overall, the sensitivity and specificity of K-ras mutation for detection of pancreaticobiliary malignancy including adenocarcinoma, intraductal papillary mucinous neoplasm, and mucinous cystic neoplasm were 57% and 94%, respectively. The positive and negative predictive values of K-ras mutation for the presence of pancreaticobiliary malignancy were 94% and 60%, respectively. CONCLUSIONS: The results demonstrate that K-ras mutation has a high predictive value for malignancy in patients with indeterminate pancreaticobiliary cytology and should be included as an important adjuvant diagnostic marker. It should be noted that a negative K-ras mutation result does not rule out malignancy, and K-ras mutation can be detected, although infrequently, in morphologically benign conditions.

Rare case of a primary non-dural central nervous system low grade B-cell lymphoma and literature review.

We present a case of a 70-year-old HIV negative man with a five-year history of progressive dysnomia and new onset right extremity numbness, dysarthria, and blurry vision. On magnetic resonance imaging (MRI), an infiltrative enhancing tumor was noted. Follow up brain biopsy results revealed a small lymphocytic infiltrate with scattered plasma cells in a predominantly perivascular growth pattern. Flow-cytometric findings revealed a lambda monotypic B-cell population. The morphology and the flow cytometric findings were consistent with involvement by a low grade B-cell lymphoma. Subsequent positron emission tomography (PET) studies along with bone marrow biopsy and serum protein electrophoresis showed no evidence of systemic disease. The above findings are consistent with involvement by a non-dural extranodal marginal zone B-cell lymphoma (MZBCL) primary to the central nervous system (CNS). This is the first reported case of a primary CNS MZBCL with flow cytometric analysis. A review of literature on this rare entity is also included.

Breast carcinomatous tumoral emboli can result from encircling lymphovasculogenesis rather than lymphovascular invasion.

The canonical view of the origin of tumor lymphovascular emboli is that they usually originate from lymphovascular invasion as part of a multistep metastatic process. Recent experimental evidence has suggested that metastasis can occur earlier than previously thought and we found evidence that tumor emboli formation can result from the short-circuiting step of encircling lymphovasculogenesis. Experimentally, we used a xenograft of human inflammatory breast cancer (MARY-X), a model that exhibited florid tumor emboli, to generate tumoral spheroids in vitro. In observational studies, we chose human breast carcinoma cases where there appeared to be a possible transition of in situ carcinoma to lymphovascular emboli without intervening stromal invasion. These cases were studied by morphometry as well as IHC with tumor proliferation (Ki-67) and adhesion (E-cadherin) markers, myoepithelial (p63), as well as endothelial (podoplanin [D2-40], CD31, VEGFR-3, Prox-1) markers. Unlabelled spheroids coinjected with either GFP or RFP-human myoepithelial cells or murine embryonal fibroblasts (MEFs) gave rise to tumors which exhibited GFP/RFP immunoreactivity within the cells lining the emboli-containing lymphovascular channels. In vitro studies demonstrated that the tumoral spheroids induced endothelial differentiation of cocultured myoepithelial cells and MEFs, measured by real time PCR and immunofluorescence. In humans, the in situ clusters exhibited similar proliferation, E-cadherin immunoreactivity and size as the tumor emboli (p =.5), suggesting the possibility that the latter originated from the former. The in situclusters exhibited a loss (50%-100%) of p63 myoepithelial immunoreactivity but not E-cadherin epithelial immunoreactivity. The tumor emboli were mainly present within lymphatic channels whose dual p63/CD31, p63/D2-40 and p63/VEGFR-3 and overall weak patterns of D2-40/CD31/VEGFR-3 immunoreactivities suggested that they represented immature and newly created vasculature derived from originally myoepithelial-lined ducts. Collectively both experimental as well as observational studies suggested the possibility that these breast cancer emboli resulted from encircling lymphovasculogenesis rather than conventional lymphovascular invasion.

Pancreatic and Gastric Plasmacytoma Presenting with Obstructive Jaundice, Diagnosed with Endoscopic Ultrasound-Guided Fine Needle Aspiration.

Pancreatic plasmacytoma is a rare disorder which may present with obstructive jaundice. Only eighteen cases have been reported in the English language literature. We present the first case of pancreatic plasmacytoma and gastric plasmacytoma diagnosed with endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). A 75-year-old male with a known history of multiple myeloma presented with obstructive jaundice and a pancreatic mass. A concomitant gastric mass due to gastric plasmacytoma was seen. The diagnosis was established via EUS-FNA of the pancreatic mass. Pancreatic plasmacytoma should be suspected in patients with a history of myeloma. EUS-FNA is a safe and effective modality in the diagnosis of pancreatic plasmacytoma. Radiation therapy should be the first-line of therapy in treating pancreatic plasmacytomas.

Cytopathologic features of olfactory neuroblastoma.

BACKGROUND: Olfactory neuroblastoma (ONB) is an uncommon neoplasm arising from the olfactory mucosa. Because its cytopathology is largely limited to case reports, the goal was to evaluate a series of ONB cases, compare them with previously reported cases, and with a control group of pulmonary and cutaneous small cell neuroendocrine carcinoma (NEC). METHODS: Six fine-needle aspiration (FNA) biopsies of metastatic ONB and one case with imprint smears of primary ONB were recovered from files. Aspirates from seven FNA cases of metastatic pulmonary small cell NEC and four cases of metastatic Merkel cell carcinoma to the head and neck functioned as a control group and were compared with those of ONB. RESULTS: Seven cases from 4 patients included 3 males (ages 33-39 yrs) and 1 female (age 58 yrs). Aspirates were acquired from soft tissues of the neck (three cases), cervical lymph nodes (two cases), parietal scalp (one case), and imprint of a nasal mass (one case). A correct cytologic diagnosis of metastatic ONB (five cases) or malignant small round cell tumor (one case) was made in six cases. One aspirate was misdiagnosed as a reactive lymph node. The single primary tumor and five of six metastatic tumors were histologically confirmed. Cytologic features were similar in all cases. These included high cellularity (seven of seven cases), distribution as single forms and cell clusters (seven of seven cases), a two-cell population of intact and apoptotic nuclei (seven of seven cases), nuclear molding (seven of seven cases), paranuclear 'blue bodies' (five of seven cases), necrosis (five of seven cases), and absence of lymphoglandular bodies (seven of seven cases). Unlike prior reports, no case exhibited rosettes or fibrillar neuropil on smears. All examples from the control group displayed nearly identical cytomorphologic features to those of the study group. CONCLUSIONS: The cytopathology of metastatic ONB is nonspecific unless fibrillar neuropil is identified. Nonetheless, a cytopathologic diagnosis of metastatic ONB can be made with confidence in nearly all patients if a well documented history of ONB exists. Minus such a clinical context, aspirates of metastatic ONB may be mistaken for metastatic pulmonary small cell NEC, cutaneous neuroendocrine (Merkel cell) carcinoma, and even small cell lymphoma.