PROJECT SUMMARY The primary goal of the supplement to be carried out by Ms. Zarate-Sanchez is to design, build, and validate an integrated “organ-on-a-chip” platform of human primary tumor and human bone marrow. This is important because: 1) all tumors engage the immune system, and thus the bone marrow (primary source of immune cells); and 2) a wide range of tumors co-opt the bone marrow to the advantage of the tumor during progression and latency (e.g., breast cancer). The research milestones include: 1) demonstrate proficiency in all steps of soft lithography, including CAD design, photolithography, and PDMS device construction; 2) demonstrate proficiency in cell culture techniques; and loading and culture of in vitro bone marrow and cancer models in the microfluidic device; 3) quantify number, phenotype, and location of the leukocytes within the microfluidic device in response to a series of breast cancer cell lines; and 4) quantify number, phenotype, and location of a series of breast cancer cells lines in the microfluidic device. In addition to the research milestones, the supplement will seek to accomplish a series of milestones associated with her career development including: 1) completing 3 elective courses; 2) mentoring undergraduate researchers; 3) presenting her work at a national meeting; 4) publishing her work in a peer-reviewed archived journal(s); and 5) submitting her own independent F31 application. Accomplishing these milestones will prepare Ms. Zarate-Sanchez for an independent and impactful scientific career.