Project Summary Funding is requested for years 41-45 of a long standing and successful training program in cancer research at The Wistar Institute. Support is requested for 4 predoctoral and 8 postdoctoral trainees. Predoctoral trainees are Ph.D. or M.D./Ph.D. candidates who conduct cancer-related thesis research at the Wistar Institute in partial fulfillment of the Ph.D. requirements of the University of Pennsylvania. Postdoctoral training is designed to prepare individuals for independent research careers in cancer- related areas in basic research and clinical settings. The program is devoted to laboratory research training that is complemented by a biweekly Research in Progress Series, a weekly cancer-focused Wistar Institute Distinguished Lecture Series, a biweekly Cancer Biology Journal Club, a biyearly Cancer Biology Retreat, a Cancer Biology Lecture Course, a yearly workshop in Grant Proposal Planning and Preparation and yearly training in The Responsible Conduct of Research. Trainees also actively participate in other relevant lectures series and national and international conferences. The proposed trainers head 20 independent laboratories from the four programs at the Wistar Institute;; Gene Expression and Regulation, Molecular and Cellular Oncogenesis, Translational Tumor Immunology and Tumor Microenvironment and Metastasis. Trainers participate in all training program activities including the recruitment into the program of Underrepresented scientists. The trainers in the program share a common interest in cancer research and together cover both basic and translational aspects. A unique feature of the program is that it is unusually interactive and collaborative, resulting in many program projects and collaborative publications involving trainers and trainees both within and between the four institute programs. All participating trainers continually succeed in attracting outstanding predoctoral and postdoctoral fellows, and each has successfully competed for predominantly federal grant support in cancer research, with 65% of the participating trainers supported by the NCI and the rest of the trainers supported by other cancer-related funding. Altogether, this program offers training in “cutting edge” research that will prepare our trainees for productive independent careers in basic and translational cancer research.