They tested multiple PIK3CA inhibitors and were able to inhibit phosphorylation and activation of AKT in multiple MCC cell lines and induce apoptosis in one line with both ZST474, a specific phosphoinositide 3-kinase (PI3K) inhibitor, and NVP-BEZ235, a dual PI3K/mTOR inhibitor. Here, PIK3CA is linked to Merkel cell skin cancer.