AUTHOR=Cao Xiying , Wu Bingqun , Guo Shaoming , Zhong Weixiang , Zhu Shenyu , Zhang Zuxiong , Gu Liang , Li Hui 

TITLE=APOC1 predicts a worse prognosis for esophageal squamous cell carcinoma and is associated with tumor immune infiltration during tumorigenesis

JOURNAL=Pathology and Oncology Research

VOLUME=Volume 29 - 2023

YEAR=2023

URL=https://www.por-journal.com/journals/pathology-and-oncology-research/articles/10.3389/pore.2023.1610976

DOI=10.3389/pore.2023.1610976

ISSN=1532-2807

ABSTRACT=Abstract
Background: Esophageal carcinoma (ESCA) is a serious threat to human health. Apolipoprotein C1 (APOC1) is involved in tumorigenesis as an inflammation-related molecule, and its role in esophageal cancer is still unknown.
Methods: We downloaded documents and clinical data using TCGA and GEO databases. We conducted bioinformatics studies on the diagnostic value, prognostic value, and correlation between APOC1 and immune infiltrating cells in ESCA through various analysis tools.
Results: APOC1 was significantly more highly expressed in tumor tissues than in normal tissues (P<0.001) in ESCA. APOC1 could diagnose ESCA accurately and determine the TNM stage and disease classification with high accuracy (area under the curve, AUC≥0.807). Kaplan–Meier curve analysis showed that APOC1 has prognostic value for esophageal squamous carcinoma (ESCC) (P=0.043). Univariate analysis showed that high APOC1 expression in ESCC was significantly associated with worse overall survival (OS) (P=0.043), and multivariate analysis shows that high APOC1 expression was an independent risk factor for the OS of patients with ESCC (P=0.030). In addition, the GO /KEGG analysis showed a concentration of gene enrichment in the regulation of T-cell activation, cornification, cytolysis, external side of the plasma membrane, MHC protein complex, MHC class II protein complex, serine-type peptidase activity, serine-type endopeptidase activity, Staphylococcus aureus infection, antigen processing and presentation, and graft-versus-host disease (all P<0.001). GSEA analysis showed that enrichment pathways such as immunoregulatory-interactions between a lymphoid and non-lymphoid cell (NES=1.493, p. adj=0.023, FDR=0.017) and FCERI-mediated NF-KB activation (NES=1.437, p. adj=0.023, FDR=0.017) were significantly enriched in APOC1-related phenotypes. In addition, APOC1 was significantly associated with tumor immune infiltrating cells and immune chemokines.
Conclusion: APOC1 can be used as a diagnostic biomarker for esophageal cancer. And it may have potential value for further investigation regarding the diagnosis and treatment of this group of patients.