Although his gastrin level decreased to 5000 pg/mL with resultant improvement of symptoms, in less than 2 years, he developed disease progression with obstructive symptomatology from enlarging gastric carcinoids and rising gastrin levels.
Those with high gastrin (Q4 vs Q1), had an increased risk of GNCA (fully adjusted OR: 1.92; 95% CI: 1.21, 3.05) and gastric carcinoids, though the small number of carcinoid cases meant the fully adjusted model was unstable (age-adjusted continuous model OR: 4.67; 95% CI: 2.67, 8.15).
The molecular studies for LOH along with the morphology and IHC profiling suggest that this second population of gastrin-positive carcinoid cells may represent a new clone within the carcinoid tumor with differentiation toward gastrin production or may represent the next step in the carcinogenic process with a gradual emergence of a more aggressive clone.
In order to gain insight into molecular mechanisms underlying proliferative responses in neuroendocrine (NE) gastrointestinal (GI) tumours, we investigated gene expression in human carcinoid BON cells after exposure to gastrin, hepatocyte growth factor (HGF), pituitary adenylate cyclase-activating polypeptide or epidermal growth factor.
We have analysed the expression and function of CCK-B/gastrin receptors in normal ECL cells and in ECL cell tumours (gastric carcinoids) of the African rodent Mastomys natalensis.
The low rate of LOH at 11q13-14 suggests the predominance of different genetic mechanisms in type III carcinoids, which also differ from other types of gastric carcinoids in the lack of a promoter role for gastrin.
To evaluate the involvement of the apoptosis-suppressing protein BCL-2 in the gastrin-dependent mechanism of induction of gastric enterochromaffin-like (ECL) cell carcinoids, the endocrine cell of the oxyntic mucosa were immunohistochemically investigated in (a) 10 normogastrinemic subjects with histologically normal gastric mucosa; (b) 22 patients with endocrine cell hyperplasia and affected by hypergastrinemic conditions with different risk of gastric carcinoid development, such as sporadic Zollinger-Ellison syndrome (sZES; n = 9), ZES associated with multiple endocrine neoplasia-1 (MEN-1; n = 4), and atrophic fundal gastritis (AFG; n = 9); (c) 14 patients with ECL gastric carcinoids accounting for a total of 31 tumors investigated.