1,721,014 research outputs found
Target gene mutations in sporadic endometrial and gastrointestinal cancers with high microsatellite instability
No full textTTF1 expression in normal lung neuroendocrine cells and related tumors. Immunohistochemical study comparing two different monoclonal antibodies
No full textThyroid transcription factor-1 (TTF1) regulates lung morphogenesis and differentiation, and its immunohistochemical
expression is used for identifying lung neoplasms. The 8G7G3/1 antibody has been used in previous studies, but a different and more sensitive anti-TTF1 antibody, named SPT24, has become commercially available. Since the immunohistochemical expression of TTF1 in normal lung neuroendocrine (NE) cells has not been previously investigated and its utility in the diagnosis of lung NE tumors is a controversial issue, we studied the TTF1 expression in normal adult and fetal lungs, in 83 pulmonary NE neoplasms, in 131 non-lung NE tumors and
in 36 metastases from these neoplasms using these two
antibodies. A TTF1 immunoreactivity was demonstrated in normal fetal and adult NE cells when using the SPT24 clone. Conversely, using the 8G7G3/1 antibody, only rare fetal neuroendocrine cells were TTF1 positive while adult
NE cells were negative. The SPT24 clone identified TTF1
expression in more carcinoids, most of them peripherally located, and poorly differentiated NE carcinomas than the 8G7G3/1 clone. Non-pulmonary well-differentiated NE tumors were negative for both antibodies. Among the 45 non-pulmonary poorly differentiated NE carcinomas 11% were positive for 8G7G3/1 and 18% for SPT24. TTF1 expression in metastases perfectly reflected that detected in
the related primary tumors. Our results indicate that the
SPT24 antibody is more sensitive than the 8G7G3/1 clone for labeling lung carcinoids and it appears particularly useful in detecting peripheral neoplasms. In addition, the
expression of TTF1 in normal NE cells suggests a possible
role for the transcription factor in their development and differentiatio
Gastrointestinal stromal tumors - frequency, malignancy, and new prognostic factors: The experience of a single institution
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Intratumor T cells and survival in gastric carcinomas characterized for microsatellite instability and Epstein Barr virus infection
No full textp16/cyclin D1/pRB pathway alterations in gastric and colorectal carcinomas analyzed for microsatellite instability
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Immunohistochemical localization of acidic fibroblastic growth factor in normal human enterocromaffin cells and related gastrointestinal tumors
No full textAcidic fibroblast growth factor (aFGF) is a member of the structurally related heparin-binding growth factor family. The best studied members of this family are aFGF and basic FGF (bFGF), which are potent mitogens and differentiation factors for mesoderm-derived cells, including fibroblasts. This study was designed to verify the immunohistochemical expression of aFGF in normal human endocrine cells of the gut and in related endocrine tumours. We examined normal gastrointestinal mucosa from seven different subjects and 41 gut endocrine tumours from different sites, including stomach, duodenum, and small and large intestine, using an aFGF polyclonal antibody with no cross-reactivity for bFGF. We localized aFGF in a fraction of serotonin-producing enterochromaffin (EC) cells of the normal gut, while it was absent in gastrin (G), CCK, secretion (S), somatostatin (D) and glicentin (L) cells. aFGF immunoreactivity was also expressed in serotonin producing EC cell tumours, but not in other functional types of gut endocrine neoplasms investigated, including gastric ECL cell, duodenal somatostatin and gastrin cell, and rectal L cell tumours. A positive correlation was found between expression of aFGF and the amount of tumour fibrous stroma, suggesting that aFGF may be involved in proliferation and activity of stromal fibroblast
Espressione del fattore di crescita epatocitario (HGF) e del suo recettore MET nelle cellule endocrine normali e nei relativi tumori dell’apparato digerente.
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