Published online Aug 24, 2023. doi: 10.5306/wjco.v14.i8.297
Peer-review started: May 10, 2023
First decision: June 7, 2023
Revised: June 19, 2023
Accepted: July 19, 2023
Article in press: July 19, 2023
Published online: August 24, 2023
Six-transmembrane epithelial antigen of the prostate 4 (STEAP4), a transmembrane protein involved in metal reductase transport of copper and iron, has been reported as a potential target for cellular and antibody immunotherapy.
Few studies on STEAP4 in gastric cancer (GC), which may play a role in the immune response to the occurrence and development of GC.
The expression of STEAP4 in GC tissues and its correlation with the level of tumor immune infiltration were comprehensively analyzed and to explore the potential immune effect of STEAP4 in GC.
The protein expression level, clinicopathological parameters and prognosis of STEAP4 in tumor and adjacent tissues of GC patients were detected by immunohistochemistry. An online database was used to study the correlation between STEAP4 and the level of tumor immunoinfiltration and the characteristics of immunoinfiltration genes. The relationship between STEAP4 expression and immune and stromal scores in the GC was analyzed by ESTIMATE algorithm.
Immunohistochemistry analysis showed that STEAP4 was highly expressed in GC and was positively correlated with the clinical stage of GC. The infiltration levels of immune cells such as B cells, CD4+ T cells, macrophages, neutrophils and dendritic cells were positively correlated with STEAP4. The expression level of STEAP4 was strongly correlated with most of the immune markers. In addition, the ESTIMATED algorithm analysis showed that the stromal, immune and estimated scores were higher in the group with high expression of STEAP4, while the tumor purity was higher in the STEAP4 Low expression group. The relationship between STEAP4 expression and prognosis of GC patients was further studied, and the results showed that high STEAP4 expression had shorter overall survival and disease-free survival. Moreover, Kaplan-Meier Plotter showed that high expression of STEAP4 was associated with poor survival in patients with GC.
STEAP4 is indicated as a potential immune indicator of GC, targeting STEAP4 may provide a new therapeutic method for GC patients.
The comprehensive analysis of STEAP4 function in GC still needs to explore the mechanism by which STEAP4 plays an immune role in GC.