Regarding GPR55 itself, our group has previously observed that this receptor is upregulated in human skin tumors and other human squamous cell carcinomas compared with the corresponding healthy tissues [19], and that high GPR55 expression correlates with high histological grade in breast, pancreas and brain tumors, as well as with decreased overall survival in glioblastoma patients [10]. Here, GPR55 is linked to squamous cell carcinoma.