AR and prostate cancer: In 2019, PROTAC ARV-110, which targets the androgen receptor (AR) for degradation in prostate cancer, has been approved by the FDA for phase I clinical trials (Neklesa et al., 2017; Pettersson and Crews, 2019; Schapira et al., 2019; Ding et al., 2020; Poh, 2020; Wang et al., 2020a).