Immune cell infiltration and drug sensitivity in PIK3CA-mutated esophageal squamous cell carcinoma: A TCGA database analysis.

Recent studies have increasingly focused on PIK3CA mutations in esophageal squamous cell carcinoma (ESCC); however, the clinicopathological significance of these mutations within the tumor microenvironment remains underexplored. This study aimed to evaluate and compare the clinicopathological significance of mutated PIK3CA in ESCC using in silico analyses of the ESCC dataset from the TCGA database. We assessed prognosis, differential expression, correlation with immune cell infiltration and immune checkpoint expression, heterogeneity, and drug sensitivity in comparison with wild-type PIK3CA. Our findings revealed that PIK3CA mutation is associated with increased tumor mutation burden and significantly correlated with the infiltration of CD4 naive and effector memory CD4 T cells. Additionally, ESCC cells harboring PIK3CA mutations exhibited reduced sensitivity to p38/JNK MAPK inhibitors compared to those with wild-type PIK3CA. Collectively, our in silico analysis suggests that mutational PIK3CA plays a role in resistance to p38 and JNK MAPK inhibitors in ESCC.