Aliases:This biomarker is also known as:
- Growth hormone release-inhibiting factor,
The hormone somatostatin (SST) has active 14 aa and 28 aa forms that are produced by alternate cleavage of the single preproprotein encoded by this gene. Somatostatin is expressed throughout the body and inhibits the release of numerous secondary hormones by binding to high-affinity G-protein-coupled somatostatin receptors. This hormone is an important regulator of the endocrine system through its interactions with pituitary growth hormone, thyroid stimulating hormone, and most hormones of the gastrointestinal tract. Somatostatin also affects rates of neurotransmission in the central nervous system and proliferation of both normal and tumorigenic cells. The promoter of somatostatin, a primary inhibitor of gastrin-stimulated gastric acid secretion, is hypermethylated in 80% of human colon cancers. A synthetic analog of SST, known as octreotide or SMS 201-995, is available under the name Sandostatin (Novartis). It is used for the treatment of a variety of disorders including acromegaly and the symptomatic treatment of carcinoid tumors and vasoactive intestinal peptide tumors.
The following organs have data associated with this biomarker…
Esophageal adenocarcinoma risk in Barrett's esophagus is increased 30- to 125- fold versus the general population. Among all Barrett's esophagus patients neoplastic progression occurs only once per 200 patient-years. Molecular markers (individual or in panel) would be useful to risk-stratify patients for more efficient surveillance endoscopy and to improve the early detection of progression.
Promoter hypermethylation of SST can distinguish esophageal squamous cell carcinomas (ESCC) and esophageal adenocarcinomas (EAC) from normal esophagus. Studies investigating potential use of this protein as a biomarker are ongoing.
Supporting Study Data
The following studies/protocols provide evidence supporting SST indications for the Esophagus…
Barrett's Esophagus Methylation Profiles
We propose a nested case-control study of biomarkers in the setting of BE. By bringing together research institutions with large populations of patients with BE, we will perform a multi-center study of FISH and hypermethylation markers as possible prognostic factors in BE. The centers will select from their cohorts who have progressed to HGD or to adenocarcinoma of the esophagus ("progressors"), and who also donated samples prior to the development of cancer, when their histology was felt to be benign. These subjects will be compared to individuals who have been under endoscopic surveillance, but who have not progressed to HGD or EAC ("non-progressors"). Using this approach, we hope to identify promising markers for risk stratification in BE. We expect to be able to make successful application for a prospective study of markers identified in this case-control study.View more about this study
Biomarker Characteristics Summary
|Notes||Sensitivity||Specificity||Prevalence||NPV||PPV||Specific Assay Type|
|Assessment of the classification accuracy of a single marker using ROC curve analyses show AUC for HPP1, p16, and RUNX3 are all significantly greater than 0.50. For SST, AUC (95% confidence interval) was 0.506 (0.401, 0.611).||N/A||N/A||N/A||N/A||N/A|
Additional Study-Specific Protocols
No study-specific resources defined.
No organ-specific protocols defined.
No organ-specific publications defined.
No organ-specific resources defined.