JDDH Journal

Abstract

Background: Gastric cancer (GC) is one of the most common gastrointestinal tumors. Due to the lack of validated biomarkers, the outcome of GC is dissatisfactory. Here, we aimed to investigate the underlying biological functions and potential mechanisms of CGB5 driving GC progression, which could provide a novel and valuable molecular target for GC diagnosis and treatment. Methods: GC samples were obtained from The Cancer Genome Atlas (TCGA). R software (×64 3.6.3) and R packages such as "ggplot2", "pROC", "GSVA" and "survival" were utilized to thoroughly analyze the effects of CGB5. IHC staining and qRT-PCR were performed to assess CGB5 levels in GC. Results: The role of CGB5 in GC was investigated and we found that the expression level of CGB5 was significantly increased in GC tissues compared to normal gastric tissues. Meanwhile, the CGB5 was highly expressed in GC cell lines. Survival analysis revealed that patients with higher CGB5 expression were correlated with poor clinical outcomes. Receiver operating characteristic (ROC) curve analysis showed the AUC value of CGB5 was 0.813, suggesting a higher accuracy in the predictive ability of the variable CGB5 in predicting normal and tumor outcomes. The potential function of CGB5 in GC tissue samples was further explored by differentially expressed genes (DEGs) analysis and gene co-expression analysis. GO and KEGG enrichment analysis indicated that CGB5 played an important role in cytokine activity and interactions. Importantly, CGB5 was closely associated with immune infiltration and tumor immune escape, and antitumor immunity was probably engaged in the CGB5-mediated oncogenesis of GC. Finally, we discovered that mutations in CGB5 had significant effects on GC. Conclusions: Our results strongly suggested an important role of CGB5 in GC. High expression of CGB5 correlated with progression and immune infiltration and could be utilized as a diagnostic/prognostic biomarker and therapeutic target, showing significant therapeutic value for GC patients.

Keywords: CGB5; Gastric Cancer; Immune Infiltration; Diagnostic/Prognostic Biomarker; Therapeutic Target.

Abbreviations

ACC: Adrenocortical Carcinoma

BLCA: Bladder Urothelial Carcinom

BRCA: Breast Invasive Carcinoma

CESC: Cervical Squamous Cell Carcinoma and Endocervical Adenocarcinoma)

CHOL: Cholangio Carcinoma

COAD: Colon Adenocarcinoma

DLBC: Lymphoid Neoplasm Diffuse Large B-Cell Lymphoma

ESCA: Esophageal Carcinoma

GBM: Glioblastoma Multiforme

HNSC: Head and Neck Squamous Cell Carcinoma

KICH: Kidney Chromophobe

KIRC: Kidney Renal Clear Cell Carcinoma

KIRP: Kidney Renal Papillary Cell Carcinoma

LAML: Acute Myeloid Leukemia

LGG: Brain Lower Grade Glioma

LIHC: Liver Hepatocellular Carcinoma

LUAD: Lung Adenocarcinoma

LUSC: Lung Squamous Cell Carcinoma

MESO: Mesothelioma

OV: Ovarian Serous Cystadenocarcinoma

PAAD: Pancreatic Adenocarcinoma

PCPG: Pheochromocytoma and Paraganglioma

PRAD: Prostate Adenocarcinoma

READ: Rectum Adenocarcinoma

SARC: Sarcoma

SKCM: Skin Cutaneous Melanoma

TGCT: Testicular Germ Cell Tumors

THCA: Thyroid Carcinoma

THYM: Thymoma

UCEC: Uterine Corpus Endometrial Carcinoma

UCS: Uterine Carcinosarcoma

UVM: Uveal Melanoma

GC: Gastric Cancer

HCG: Human Chorionic Gonadotropin

CGB5: Chorionic Gonadotropin Subunit Beta 5

TCGA: The Cancer Genome Atlas

Gtex: Genotype-Tissue Expression Project

STAD: Stomach Adenocarcinoma

VEGF: Vascular Endothelial Growth Factor

ROC: Receiver Operating Characteristic

KM: Kaplan-Meier

PPI: Protein-Protein Interaction

OS: Overall Survival

RFS: Recurrence Free Survival

DFS: Disease Free Survival

PFI: Progress Free Interval

GO: Gene Ontology

BP: Biological Process

CC: Cellular Component

MF: Molecular Function

KEGG: Kyoto Encyclopedia of Genes and Genomes

GES-1: The Normal Gastric Epithelial Cells

DEGS: Differentially Expressed Genes

GENT2: Gene Expression Database of Normal and Tumor Tissues 2

TCIA: The Cancer Immunome Atlas