Abstract Current in vitro and in vivo models for prostate cancer do not accurately recapitulate many critical aspects of prostate cancer biology. In vitro cell culture systems lack tissue architecture, complex cellular interactions, and the prostate microenvironment. Neither xenograft nor transgenic models generate authentic prostate pathobiology, and genetic and molecular fidelity is often a concern both in vitro and in vivo. Ex vivo organotypic culture systems have been used as valuable research models for several tissue types. Our lab has recently established a tissue slice graft model for prostate cancer in vivo using precision-cut 300 micron slices of radical prostatectomy tissue implanted under the mouse renal capsule. We have also developed a complimentary in vitro tissue slice culture (TSC) model that we have used for a variety of studies, including evaluation of the DNA damage response in normal cell types of the prostate. The main challenges for normal prostate TSC are maintaining luminal cell integrity beyond 48 hours and preventing hyperproliferation of basal cells. Less is known about the maintenance of cancer in TSCs. We have compared several culture conditions and can maintain normal prostate structure and function up to 4 days using PFMR-4A media supplemented with cholera toxin, epidermal growth factor, bovine pituitary extract, phosphoethanolamine, hydrocortisone, selenium, gentamycin, retinoic acid, insulin, vitamin E, and androgen R1881. Dose-response and time-course experiments revealed that the optimal concentration of R1881 for luminal cell integrity is 50nM. We verified expression of luminal and basal cell-specific markers by immunofluorescence of frozen sections, and we observed secretion of PSA by ELISA. In addition, confocal microscopy is a useful technology for visualizing the 3-dimensional architecture of TSCs. With robust survival of TSCs up to 4 days in vitro, we have a wide range of ongoing and future experimental directions including drug delivery and cell targeting, invasion and migration studies, and metabolic and molecular profiling. Furthermore, we are poised for collaboration with those who want to test their experimental methods in an intact prostate cancer model in vitro. The prostate TSC model is undoubtedly more authentic than current in vitro models, and we are optimizing its utility with the goal of executing more realistic pre-clinical studies. This abstract is also presented as Poster A69. Citation Format: Sophia Lisette Maund, Rosalie Nolley, Donna Peehl. Optimization and applications of a tissue slice culture model of the normal and malignant human prostate [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr PR2.