The Tumorigenesis Program at AFCRI is focused on molecular genetic approaches to understand cancer susceptibility and pathogenesis. The twelve investigators within this group use genetically-engineered mouse models in combination with patient material to investigate the mechanistic basis of cancer initiation, progression, and metastasis. The impact of normal developmental events on cancer susceptibility and the role played by oncogenes and tumor suppressors in the transformation process are also evaluated using state-of-the-art approaches. This program is comprised of highly complimentary laboratories with expertise in cancer biology, genomics, epigenetics, metabolism, immunology, structural biology, the tumor microenvironment, and tissue homeostasis, and includes the research groups of Drs. Irfan Asangani, Lewis Chodosh, Karin Eisinger, David Feldser, Malay Haldar, Xianxin Hua, Brian Keith, Ronen Marmorstein, Andy Minn, Warren Pear, Sandra Ryeom, Celeste Simon, Nancy Speck, and Ben Stanger. The Tumorigenesis Program continues to be an excellent resource for colleagues within the AFCRI and more broadly at Penn. Scientific collaborations connect members of this program, not only with each other, but also with other AFCRI investigators as well as faculty outside of the Institute. Papers from this group have been published in top-tier journals such as Nature, Cell, Cell Stem Cell, Genes and Development, Nature Cell Biology, Cancer Cell, and Cancer Discovery. This program is also the base for two NCI-funded P01s that involve at least two members of the listed faculty, and each provides resources for our core facilities. A variety of cancers are studied by these researchers, including melanoma, pancreatic cancer, lung adenocarcinoma, prostate cancer, sarcoma, breast cancer, and hematological malignancies.