Expression of AOX1 in Clear Cell Renal Cell Carcinoma: Potential Prognostic Biomarker?
Posted: Wednesday, September 8, 2021
Hongjie Wang, MD, PhD, of Tongji Hospital, Tongji Medical College, Wuhan, China, and colleagues sought to identify whether the expression of aldehyde oxidase 1 (AOX1) had any effect on clear cell renal cell carcinoma. Their results, published in Frontiers in Genetics, not only identified AOX1 as a suppressor gene but also found that low AOX1 expression predicted worse overall survival in patients with renal cell carcinoma.
The Gene Expression Omnibus—the public functional genomics data repository of the National Center for Biotechnology Information—was reviewed for data sets involving clear cell renal cell carcinoma. A total of eight data sets—GSE15641, GSE68417, GSE46699, GSE53757, GSE40435, GSE36895, GSE16441, and GSE16449—were used. Further data were obtained from The Open Targets Platform, the Search Tool for the Retrieval of Interacting Genes database, and The Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma data set.
A total of 331 normal kidney and 374 clear cell renal cell carcinoma samples were analyzed from the data sets. Compared with normal kidney tissues, 211 and 145 genes were observed to be significantly downregulated and upregulated in carcinoma tissues, respectively. From The Cancer Genome Atlas, AOX1 gene expression data were analyzed from 533 clear cell renal cell carcinoma tissues and 72 normal kidney tissues. Despite identifying a similar AOX1 expression in both tissues, the investigators found that expression of the AOX1 protein was two and a half times higher in normal samples.
Eligible patients with clear cell renal cell carcinoma (n = 516) from The Cancer Genome Atlas database were reviewed to determine a correlation between AOX1 expression and overall survival. It was discovered that patients who had low AOX1 mRNA expression levels had a worse overall survival than those with high levels, suggesting that AOX1 expression may be predictive of prognosis. Of note, Cox regression analysis confirmed that higher AOX1 expression may exhibit a protective role.
Disclosure: The study authors reported no conflicts of interest.