Abstract P3-09-02: Pateint Derived Breast Cancer Organoids as a Model for Testing Personalized Therapies

Abstract

Abstract Introduction: Breast cancer is one of the most frequently diagnosed cancer in women with a high mortality rate. More than 20 different subtypes of breast cancer are identified. Advancement in patient-derived organoid technology makes it possible to preserve cellular, structural, and tissue microenvironment which mimics the tissue in vivo. Method: We developed patient derived breast organoids both from normal and cancer biopsies recapitulate the structure of breast tissue. Breast biopsies were enzymatically digested to yield a single cell suspension. About 1 × 105 cells were encapsulated in a specialized hydrogel mixture. Immune enhanced breast tumor organoids (iTOs) included 2 × 105 patient matched PMBCs. Results: Histological analyses of the breast organoids shows the characteristics of the breast tissue with well-defined acini in H&E. In tumor organoids acini were somewhat perturbed compared to normal breast organoids. Immuno-fluorescence staining shows the expression of breast biomarkers including EGF receptor 2 (HER2), Progesterone receptor (PR), Estrogen receptor (ER). Zona occludin 1 and 2 and keratin 19 expression in luminal cells and expression of Keratin 14 and P63 in basal cells suggested correct polarization in the organoids. Immunofluorescence staining of (iTOs), with T cell markers including CD3, CD4, and CD8 indicated that immune cells remained viable in the iTOs. Drug responses to Doxorubicin, Paclitaxel and a combination of Doxorubicin-Paclitaxel showed significant inhibition of cell growth in normal and tumor organoids (p< 0.04, n=11) except for Paclitaxel failed to inhibit tumor cell growth. However, immunotherapy with nivolumab (anti PD-1) showed no significant effect on cell growth. Conclusions: Pateint Derived Breast cancer organoids recapitulate the histological features of breast tissue in culture and response to chemotherapies. In the future, patient-derived tumor organoids can provide a platform for personalized medicine. Citation Format: Nadeem Wajih, Richard Erali, Steven Forsythe, Shay Soker, Konstantinos Votanopoulos. Pateint Derived Breast Cancer Organoids as a Model for Testing Personalized Therapies [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-09-02.