Kamryn Graham, a senior biology major and genomics minor at Davidson College, characterized the development of EZR and RhoA gene dependencies in colorectal cancer organoids.
Various cancer studies have highlighted two genes, ezrin (EZR) and ras homolog A (RhoA), as metastatic cancer biomarkers because of their roles in facilitating cytoskeletal rearrangements, cell polarity, adhesion, and–when upregulated–cell motility. The Broad is not only a place of cutting edge science, but a place that does not remove the person from the project. Being able to show up as my whole self and be supported by my mentor, cohort, and BSRP staff, allowed me to grow in ways I never imagined. I am not only a better scientist because of this program, but I am a better leader and person for any community I will be a part of in the future because of the growth I experienced Previously, we have found that EZR and RhoA dependencies were enriched in vivo, with EZR displaying a stronger dependency, indicating that each gene may contribute to interactions in the tumor microenvironment that are not maintained in 2D tissue culture. Therefore, to develop an improved in vitro model of these in vivo dependencies, we engineered an EZR knockout in cancer organoids selected from the Human Cancer Models Initiative (HCMI) catalog. Organoids allow us to analyze the contribution of resource and spatial competition, cell-cell interactions, cell differentiation, cell state, and differential protein localization to tumor cell survival in vitro, thus allowing us to more adequately model the complexity of in vivo gene dependencies. Using immunofluorescence microscopy, we visualized the localization of EZR and RhoA in 2D cancer cell lines and cancer organoids to understand how differences in localization might explain observed dependencies or contribute to tumor development. Our visualization allowed us to monitor how EZR and RhoA dependencies may form as the organoid structure develops. Additionally, the role of both proteins in cytoskeletal organization and cell migration could indicate a mechanism where cancer cell interactions and communication are required for tumor survival and proliferation, meaning our investigations into both dependencies could be doorways to target metastatic tumors therapeutically.
Project: Modeling in vivo cancer dependencies on ezrin and ras homolog A using engineered organoids
Mentor: Dean Procter PhD, Golub Lab, Cancer Program