Abstract Work in models of embryonic development shows that membrane voltage, or resting potential (Vmem), regulates cell behaviors that are disrupted in cancer, including proliferation, migration, apoptosis, homeostasis, and cell-cell signaling. Normal cells and tissues maintain stereotypical patterns of Vmem and these patterns are recognizable in Vmem Imaging as bioelectric signatures. In embryonic tissues, cells that are relatively undifferentiated are usually less negative (depolarized) than fully differentiated cells, and different cell lineages have characteristic bioelectric signatures. Recently, the development of innovative imaging technologies using Voltage Sensitive Dyes (VSDs) allows the visualization of Vmem in living cells and tissues. In culture, Vmem Imaging using VSDs can readily differentiate between sister breast cancer cell lines of low and high metastatic potential (EpH4 and EpH4.2, respectively). Although the cultures are identical in bright field images, Vmem Imaging shows a dramatically more heterogeneous bioelectric signature for EpH4.2 than for EpH4 cells, consistent with reduced gap junctional communication. One of the challenges of Vmem Imaging has been the limited thickness of tissue that can be analyzed using the VSDs (about 50 microns). To overcome this limitation, we have combined innovative Tissue Print technologies with Vmem Imaging in order to visualize patterns of electric potential in living cancer cells obtained from human surgical specimens. Tissue Prints are touch preps that transfer a thin layer of viable cells to a nitrocellulose membrane as an oriented imprint; biomarkers identified on these tissues prints can be mapped back to the source tissue to establish pathology and gene expression correlations. Tissue Print Vmem Imaging of radical prostatectomy specimens shows differentiation of bioelectric signatures between cancer and adjacent benign tissue and between cancer of different grades (Gleason pattern 3 and pattern 4). Such differences in bioelectric signatures represent unexplored cancer phenotypes that are made accessible by Tissue Print Vmem Imaging technologies. Citation Format: Dany S. Adams, Brian H. Tracey, Larry Takiff, James Kearns, Stephen P. Naber, Sandra M. Gaston. Tissue print Vmem imaging: Visualizing bioelectric signatures in cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1933.