Patient-derived tumor organoids for new drug development: promises and challenges.

The development of antitumor drugs is affected by various unfavorable factors, including long cycles of research and development, large differences in drug efficacy in vivo, and efficacy differences in individuals. Patient-derived tumor organoids (PDTOs), a novel preclinical model in cancer research, are three-dimensional microstructures differentiated from stem cells, with the capability of self-organizing into micro-organs that resemble the original tumor tissues. They have been demonstrated to faithfully recapitulate the biological and molecular features of the original tumor while preserving the tumor heterogeneity. Recently, PDTOs show great potential in drug screening and new drug development. In this review, we overviewed the types of organoids, application of PDTOs in developing new drugs, as well as their challenges and opportunities to provide powerful insights into drug development.