Oncogenic and immunological role of EDIL3 in human tumours: From pan-cancer analysis to validation in gastric cancer

Background: Epidermal growth factor-like repeats and discoidin I-like domains 3 (EDIL3) is a secreted extracellular matrix protein implicated in diverse physiological and pathological processes including embryonic development, angiogenesis, and anti-inflammatory responses. Recent reports have indicated that EDIL3 play critical roles in carcinogenesis and progression of many cancers. Herein, we performed a pan-cancer investigation to study the potential functions of EDIL3 in various cancers and experimentally validate its function in gastric cancer (GC). Methods: We analysed EDIL3 expression profiles in different tumours using The Cancer Genome Atlas database. The Kaplan-Meier Plotter was used to investigate the prognostic value of EDIL3, while receiver operating characteristic curve was performed to analyze its diagnostic efficacy. Several bioinformatics tools were used to study the association between EDIL3 and promoter methylation, gene enrichment analysis, immune infiltration, immune-related genes, and drug sensitivity. Molecular biology experiments were conducted to validate the tumorigenic effects of EDIL3. Results: EDIL3 is variably expressed in different cancers and is closely associated with clinical outcomes. An inverse correlation between EDIL3 and DNA methylation has been observed in 13 cancers. Enrichment analysis indicated that EDIL3 is correlated with many cellular pathways such as extracellular matrix receptor interactions and focal adhesion. EDIL3 was tightly associated with immune infiltration and immune checkpoints. EDIL3 knockdown can promote GC calls apoptosis while preventing proliferation, migration, and invasion in vitro. Conclusion: EDIL3 is a promising prognostic, diagnostic, and immunological biomarker in various cancers, which could be applied as a new target for cancer therapy.