Bioinformatics analysis identifying FBXO45 gene as a potential oncogene in esophageal cancer

F-box protein 45 (FBXO45) is a member of the F-box protein family, and is reportedly involved in the progression of many diseases. However, its role in esophageal cancer (ESCA) remains unclear.

The expression, clinical characteristics, gene function, pathway, and correlation between the infiltration of different immune cells were analyzed using public data. The pan-cancer expression of FBXO45 was assessed using the TIMER2 database. The expression of FBXO45 in different tumor stages and histology subtypes were evaluated using the UALCAN database. The protein-protein interaction (PPI) network was constructed using the STRING database. Immune cell infiltration data were downloaded from the ImmuCellAI database.

The top 300 genes most positively correlated with FBXO45 were screened into the enrichment analysis. The functional enrichment results showed that FBXO45 was mainly associated with proteasomal protein catabolic process and the regulation of DNA metabolic processing in the biological process (BP) category; spindle, chromosomal region, and focal adhesion in the cellular component category; and ATPase activity and ubiquitin-protein transferase activity terms in the molecular function category. FBXO45 was overexpressed in ESCA and other cancer types. FBXO45 expression was positively associated with the infiltration levels of immunosuppressive cells, such as CD8⁺ (cluster of differentiation 8+) T cells and NK (natural killer cell) cells, in ESCA. MYCBP2 and SKP1 were most associated with FBXO45.

Our results suggested that FBXO45 is a potential oncogene in ESCA. Elevated FBXO45 expression indicates a relatively immunosuppressive microenvironment.