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Simona Grozinsky-Glasberg, Ilan Shimon, Márta Korbonits, and Ashley B Grossman

characteristics ( Oberg 2005 ). NETs include endocrine glands (the pituitary, the parathyroid or the neuroendocrine adrenal glands), endocrine islets (within the thyroid gland or the pancreas) as well as endocrine cells distributed between exocrine cells

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S Pelengaris and M Khan

Pancreatic islet neoplasms are rare endocrine tumours. The most common type is of beta-cell origin and is known as insulinoma, which can be either benign or malignant. The majority of insulinomas arise sporadically, but a small proportion develop as part of the hereditary multiple endocrine neoplasia type 1 (MEN1) syndrome. As for many human tumours, the genetic events that occur during the initiation and progression of insulinoma are poorly known. The men1 gene product, menin, is deficient in most hereditary cases, but is not obviously affected in the majority of sporadic tumours. Activation of the proto-oncogenes c-myc and ras has been observed during malignant progression, but their role in tumour initiation remains unproven. To address these questions, transgenic mouse models have been increasingly used to explore molecular and genetic events that might also precipitate human neoplasia. Transgenic mice expressing SV40 large T-antigen (Tag) oncogene in beta-cells develop tumours in a multi-stage progression from hyperplasia, angiogenesis, to solid encapsulated tumours. However, Tag, which inactivates the key tumour suppressors p53 and Rb, is not known to be involved in the pathogenesis of human insulinoma. The proto-oncogene, c-myc is implicated in beta-cell growth in both diabetes and tumorigenesis. Activation of Myc appears to be an early event in progression of human insulinoma. The effect of deregulated Myc expression on adult beta-cells in vivo has recently been investigated by developing transgenic mouse models in which the activity of Myc can be regulated ectopically. Although Myc activation initially promotes both proliferation and apoptosis in pancreatic beta-cells, apoptosis is the predominant outcome, giving rise to islet involution and diabetes. Importantly, inhibiting Myc-induced apoptosis (by co-expression of Bcl-x(L)) leads to significantly enlarged islets, many becoming highly vascularized, hyperplastic and invasive. These results suggest that, in the pancreatic beta-cells, early suppression of apoptosis is essential for the survival of Myc-activated beta-cells and islet neoplasia.

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Guido Rindi and Frediano Inzani

-known example of regulatory function supported by neuroendocrine cells at local level. Other cell types exert classical endocrine systemic function as in the pituitary or in the islet of Langerhans of the pancreas. Neuroendocrine cells in the gut develop via a

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S L Asa, O Casar-Borota, P Chanson, E Delgrange, P Earls, S Ezzat, A Grossman, H Ikeda, N Inoshita, N Karavitaki, M Korbonits, E R Laws Jr, M B Lopes, N Maartens, I E McCutcheon, O Mete, H Nishioka, G Raverot, F Roncaroli, W Saeger, L V Syro, A Vasiljevic, C Villa, A Wierinckx, J Trouillas, and and the attendees of 14th Meeting of the International Pituitary Pathology Club, Annecy, France, November 2016

Since the early work of Minkowski, who attributed acromegaly to a pituitary tumor ( Minkowski 1887 ), neoplasms composed of pituitary adenohypophysial cells have been recognized as the cause of significant illness. However, Harvey Cushing

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Tiago Bordeira Gaspar, José Manuel Lopes, Paula Soares, and João Vinagre

. 2011 , Dasari et al. 2017 ). PanNENs originate from a network of endocrine cells that includes islet cells and pluripotent precursors in the pancreatic ductal epithelium ( Asa 2011 ). Clinically, PanNENs can be divided into functioning PanNENs (F

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G Capurso, S Lattimore, T Crnogorac-Jurcevic, F Panzuto, M Milione, V Bhakta, N Campanini, S M Swift, C Bordi, G Delle Fave, and N R Lemoine

Introduction Pancreatic endocrine tumours (PETs) are rare neoplasms arising from pancreatic islet cells, and are classified as functioning (F) or non-functioning (NF), depending on the presence/absence of an associated syndrome due

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Kenzo Nakano, Toshihiko Masui, Akitada Yogo, Yuichiro Uchida, Asahi Sato, Yosuke Kasai, Kazuyuki Nagai, Takayuki Anazawa, Yoshiya Kawaguchi, and Shinji Uemoto

reported ( Bertolino et al. 2003 , Loffler et al. 2007 ), the islet tumours in the Men1 +/ΔN3-8 mice consisted of chromogranin A-positive cells without severe atypia; moreover, they were highly vascularised, sharing the characteristics of human well

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V Fendrich, C L Lopez, J Manoharan, K Maschuw, S Wichmann, A Baier, J P Holler, A Ramaswamy, D K Bartsch, and J Waldmann

2011b Hedgehog inhibition with the orally bioavailable Smo antagonist LDE225 represses tumor growth and prolongs survival in a transgenic mouse model of islet cell neoplasms . Annals of Surgery 254 818 – 823 . (discussion 823) ( doi:10.1097/SLA

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Atsuko Kasajima and Günter Klöppel

of the resemblance of their cells with those of the islets. In 1995, it was suggested to call the islet cell tumor and the carcinoid of the stomach, intestinum and lung ‘neuroendocrine tumor’ in order to make the terminology of all these neoplasms

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Emmanouil Saloustros, Paraskevi Salpea, Matthew Starost, Sissi Liu, Fabio R Faucz, Edra London, Eva Szarek, Woo-Jin Song, Mehboob Hussain, and Constantine A Stratakis

well as cell transcription ( Bossis & Stratakis 2004 ). Thus, in patients with CNC, PRKAR1A seemingly functions as a tumor suppressor gene ( Boikos & Stratakis 2006 , 2007 ). An unexpectedly high prevalence of rare pancreatic neoplasms has been