Novel protein pathways in development and progression of pulmonary sarcoidosis.

Pulmonary involvement occurs in up to 95% of sarcoidosis cases. In this pilot study, we examine lung compartment-specific protein expression to identify pathways linked to development and progression of pulmonary sarcoidosis. We characterized bronchoalveolar lavage (BAL) cells and fluid (BALF) proteins in recently diagnosed sarcoidosis cases. We identified 4,306 proteins in BAL cells, of which 272 proteins were differentially expressed in sarcoidosis compared to controls. These proteins map to novel pathways such as integrin-linked kinase and IL-8 signaling and previously implicated pathways in sarcoidosis, including phagosome maturation, clathrin-mediated endocytic signaling and redox balance. In the BALF, the differentially expressed proteins map to several pathways identified in the BAL cells. The differentially expressed BALF proteins also map to aryl hydrocarbon signaling, communication between innate and adaptive immune response, integrin, PTEN and phospholipase C signaling, serotonin and tryptophan metabolism, autophagy, and B cell receptor signaling. Additional pathways that were different between progressive and non-progressive sarcoidosis in the BALF included CD28 signaling and PFKFB4 signaling. Our studies demonstrate the power of contemporary proteomics to reveal novel mechanisms operational in sarcoidosis. Application of our workflows in well-phenotyped large cohorts maybe beneficial to identify biomarkers for diagnosis and prognosis and therapeutically tenable molecular mechanisms.

FNAB cytology of extra-cranial metastasis of glioblastoma multiforme may resemble a lung primary: a diagnostic pitfall.

BACKGROUND: As extra-cranial metastasis of glioblastoma multiforme (GBM) is rare, it may create a diagnostic dilemma especially during interpretation of fine needle aspiration biopsy (FNAB) cytology. CASE PRESENTATION: We present transbronchial FNAB findings in a 62-year-old smoker with lung mass clinically suspicious for a lung primary. The smears of transbronchial FNAB showed groups of cells with ill-defined cell margins and cytological features overlapping with poorly differentiated non-small cell carcinoma. The tumor cells demonstrated lack of immunoreactivity for cytokeratin, thyroid transcription factor-1, and usual neuroendocrine markers, synaptophysin and chromogranin in formalin-fixed cellblock sections. However, they were immunoreactive for the other neuroendocrine immunomarker, CD56, suggesting neural nature of the cells. Further scrutiny of clinical details revealed a history of GBM, 13 months status-post surgical excision with radiation therapy and systemic chemotherapy. The tumor recurred 7 months earlier and was debulked surgically and with intra-cranial chemotherapy. Additional evaluation of tumor cells for glial fibrillary acidic protein (GFAP) immunoreactivity with clinical details resulted in final interpretation of metastatic GBM. CONCLUSION: Lack of clinical history and immunophenotyping may lead to a diagnostic pitfall with possible misinterpretation of metastatic GBM as poorly differentiated non-small cell carcinoma of lung in a smoker.

Norepinephrine induces alveolar epithelial apoptosis mediated by alpha-, beta-, and angiotensin receptor activation.

Norepinephrine (NE) induces apoptosis in cardiac myocytes, and autocrine production of angiotensin (ANG) II is required for apoptosis of alveolar epithelial cells (AECs) (Wang R, Zagariya A, Ang E, Ibarra-Sunga O, and Uhal BD. Am J Physiol Lung Cell Mol Physiol 277: L1245--L1250, 1999; Wang R, Alam G, Zagariya A, Gidea C, Pinillos H, Lalude O, Choudhary G, and Uhal BD. J Cell Physiol 185: 253--259, 2000). On this basis, we hypothesized that NE might induce apoptosis of AECs in a manner inhibitable by ANG system antagonists. Purified NE induced apoptosis in the human A549 AEC-derived cell line or in primary cultures of rat AECs, with EC(50) values of 200 and 20 nM, respectively. Neither the alpha-agonist phenylephrine nor the beta-agonist isoproterenol could mimic NE when tested alone but when applied together could induce apoptosis with potency equal to NE. Apoptosis and net cell loss (47--59% in 40 h) in response to NE was completely abrogated by the ANG-converting enzyme inhibitor lisinopril or the ANG II receptor antagonist saralasin, each at concentrations capable of blocking Fas- or tumor necrosis factor-alpha-induced apoptosis. These data suggest that NE induces apoptosis of human and rat AECs through a mechanism involving the combination of alpha- and beta-adrenoceptor activation followed by autocrine generation of ANG II.