Moreover, it has been reported that low expression of S1PR1 correlates with a poor prognosis in breast cancer patients [95], whereas a recent paper by Karam et al. 2022 indicates that a high plasma S1P level was associated with a significant increase in the overall survival of patients having a metastatic pancreatic adenocarcinoma treated by gemcitabine [54]. Here, S1PR1 is linked to breast cancer.