Expression of lysine oxidase in primary lesion of esophageal cancer and its effect on prognosis of patients with bone metastases based on bioinformatics

Objective To explore the expression and clinical significance of lysine oxidase (Lox) in primary lesion of esophageal carcinoma (ESCA) and bone metastasis lesion based on bioinformatics.

Methods The Cancer Genome Atlas (TCGA) and Gene Expression Profiling Interactive Analysis (GEPIA) databases were used to screen for differentially expressed genes between ESCA and normal esophageal tissues. Follow-up information of patients with surgery for esophageal cancer in the Fourth Hospital of Hebei Medical University from January 2016 to December 2020 were screened, and the clinical materials of patients diagnosed as bone metastasis during the follow-up period were collected. Western blot was used to verify the expression of Lox in ESCA and normal esophageal tissues; immunohistochemical staining was used to detect the expression of Lox in human ESCA tissue and normal tissue; the impact of Lox expression on survival was explored by Kaplan-Meier curve and Cox regression.

Results Through the analysis of ESCA data in GEPIA and TCGA databases, it was found that the expression of Lox in ESCA lesions was significantly higher than that in normal tissues (P<0.05); the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses found that Lox may be involved in the information conduction of various signaling pathways; the Western blot result showed that the expression of Lox in cancer tissue was higher than that in adjacent normal tissue (P<0.05); the analysis of follow-up data found that patients with high expression of Lox were more likely to have multiple bone metastases; survival analysis revealed that patients with high Lox expression had significantly shorter bone metastasis free survival and overall survival compared to patients with low Lox expression (P<0.05); Cox regression found that Lox was an independent risk factor for prognosis of patients with esophageal cancer bone metastasis.

Conclusion Lox is highly expressed in ESCA and significantly related to clinical prognosis, which can be used as an effective target for the diagnosis and treatment of ESCA.