ADORA2A and cancer: Htr1a is a serotonin receptor primarily studied in the brain, while adora2 and adgrf1 are more widely present and implicated in inflammation, cardiovascular diseases, and cancer (Borea et al., 2018; Huang et al., 2020; Lucki, 1998; Marzo, 2018; Park et al., 2019; Pasquini et al., 2021; Saini et al., 2022).