As the tested cSCC cells derive from either moderately or poorly differentiated primary tumors [34], these results are consistent with data from our previous mutational pathway analysis of 40 primary cSCC tumors that identified the PI3K/Akt pathway amongst the KEGG signaling pathways that were more mutated in the moderately differentiated/poorly differentiated group [35]. Here, PIK3CD is linked to skin squamous cell carcinoma.