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Updated: Jun 30, 2026
05:51
Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells
Published on: June 15, 2013
Gene expression profiles associated with stimulus-responsive insulin secretion in insulinoma
Kenji Sugawara1, Yuko Okada2, Tomokazu Matsuda3
1Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Graduate School of Medicine , Kobe, Japan.
Endocrine Connections
|June 29, 2026
Summary
Clinical differences in insulinoma (a type of pancreatic neuroendocrine tumor) may stem from varying tumor responses to stimuli and glucose sensing. This study explores these mechanisms in four patients.
Area of Science:
- Endocrinology
- Oncology
- Molecular Biology
Background:
- Insulinoma, a functional pancreatic neuroendocrine tumor, typically causes fasting hypoglycemia due to autonomous insulin secretion.
- Some insulinomas exhibit postprandial or stimulus-induced hypoglycemia, indicating retained responsiveness to physiological cues.
Purpose of the Study:
- To investigate the clinical heterogeneity of insulinoma by integrating stimulation tests with DNA microarray analysis.
- To explore the relationship between clinical presentation and molecular characteristics of insulinoma.
Main Methods:
- Four patients with confirmed insulinoma underwent integrated clinical stimulation tests (oral glucose tolerance, meal tolerance, glucagon stimulation).
- Insulin secretory dynamics were assessed.
- DNA microarray analysis was performed for transcriptomic profiling.
Main Results:
- Case 1, with postprandial hypoglycemia, showed marked insulin secretion in response to stimuli and preserved gene expression related to glucose sensing and beta-cell function.
- Cases 3 and 4, with early fasting hypoglycemia, displayed weaker secretory responses and distinct gene expression patterns, including higher hexokinase 1 and stress-response genes.
- Transcriptomic analysis revealed distinct clustering based on clinical presentation and hypoglycemia patterns.
Conclusions:
- Clinical heterogeneity in insulinoma may be linked to differences in beta-cell-like stimulus-response mechanisms.
- Variations in glucose sensing, stress responses, and differentiation status likely contribute to the diverse clinical manifestations of insulinoma.
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