Related Experiment Video
Updated: Sep 16, 2026
Multi-Gene Single Nucleotide Polymorphism Detection in Gastric Cancer Based on Ion Semiconductor Sequencing Platform
Published on: May 10, 2024
FGF19 as a site-specific candidate biomarker in colorectal neuroendocrine carcinomas
Jinping Zhang1, Weili Long2, Jing Ma1
1Department of Pathology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, 646000, China; Precision Pathology Diagnosis for Serious Diseases Key Laboratory of LuZhou, Luzhou, Sichuan, 646000, China.
Purpose:
Gastrointestinal neuroendocrine carcinomas (GI-NECs) are aggressive tumors with marked site-specific heterogeneity, yet molecular markers for colorectal origin are lacking. This study characterized genomic and protein expression profiles to identify origin-specific biomarkers.
Methods:
Nineteen GI-NECs (7 esophageal, 6 gastric, 6 colorectal) were analyzed by targeted next-generation sequencing (NGS) of 425 genes and immunohistochemistry (IHC). Genetic variations across primary sites were compared, and associations between FGF19 expression, clinicopathological features, microsatellite (MS) status, and tumor mutational burden (TMB) were assessed. FGF19 transcriptional expression was further examined in The Cancer Genome Atlas (TCGA) colorectal cohort using the UALCAN platform.
Results:
A total of 163 genomic alterations were identified. FGF19 was the only gene showing site-specific alterations, being exclusively mutated or amplified in colorectal NECs (50%, 95% CI: 11.8-88.2%) with significantly elevated protein expression (83.3%, 95% CI: 35.9-99.6%) compared with other sites. A microsatellite instability-high (MSI-H) subgroup (10.5%, 95% CI: 1.3-33.1%) exhibited markedly higher TMB. TCGA data confirmed upregulated FGF19 in colorectal tumors but showed no survival association, consistent with the prognostic neutrality in our cohort.
Conclusions:
FGF19 may act as a site-specific candidate biomarker for colorectal NECs, with 83.3% protein positivity and exclusive site-specific alterations in 50% of cases. Detection of MSI-H suggests that mismatch repair (MMR) testing may be considered in selected patients with suggestive clinical or family histories to inform immunotherapy decisions.