Histology Staining of Organoid Samples

The histology staining protocol followed the methods in the previous study [23 (link)]. Briefly, organoids were washed twice with cold PBS, fixed with 4% paraformaldehyde for 15 minutes, and then removed into the mold to dehydrate and embedded in paraffin. Sections were subjected to standard H&E, IHC, and IF staining. The following primary and secondary antibodies were used in this study: Cytokeratin 5 (CK5,1:200, EP1601Y, Invitrogen), Cytokeratin 8 (CK8, 1:200, sc-8020, Santa cruz), p63 (1:200, ab735, Abcam), Aquaporin 5 (AQP5, 1:400, ab92320, Abcam), alpha-smooth muscle actin (SMA,1:200, ab7817, Abcam), DOG-1 (GT205402, GeneTech), SOX-10 (GT221002, GeneTech), C-erbB-2 (HER-2, GT224502, GeneTech), Androgen receptor (AR, GM356202, GeneTech), MUC-4 (GT227502, GeneTech), PTP4A1(1:400, DF12458, Affinity), NEFL (1:50, ab223343, Abcam), Alexa Fluor 488 (1:300, A-21206, Invitrogen), Alexa Fluor 555 (1:300, A-31570, Invitrogen). Images were acquired with Olympus BX35 microscope and Olympus laser confocal microscope FV3000.