For example, the EP4 receptor, the predominant PGE2 receptor subtype in HT-29 and HCA-7 human colon cancer cell lines, activates PI3K and induces Ca2+ influx from the extracellular space through Orai1, resulting in ERK phosphorylation and migration of oral cancer cells (Osawa et al., 2020). This evidence concerns the gene ORAI1 and lip and oral cavity carcinoma.