Characterization and functional analysis of the new microtubule associated protein RITA in the development of breast cancer

• Applicant: Professorin Dr. Juping Yuan
• Subject Area: Gynaecology and Obstetrics
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 508177751

Breast cancer, a global health concern, is the primary cause of death among women worldwide. Despite significant achievements, breast cancer metastasis remains largely incurable. Uncontrolled cell migration and invasion is central to the metastatic process. Microtubules exert spatiotemporal control in cell migration and invasion. Being associated with various regulatory and motor proteins, they interact with diverse components of the cell migration machinery and regulate cell polarity, intracellular trafficking and focal adhesion turnover. Dysfunctional microtubules result in uncontrolled migration of malignant cells and promote the development of malignancy. We have identified that RITA, the RBP-J interacting and tubulin associated protein, is crucial in regulating microtubule dynamics and the activation of Aurora A, a frequently deregulated kinase in various tumors, suggesting the involvement of RITA in oncogenesis. In fact, RITA is highly expressed in anal carcinoma tissues and its expression level is negatively correlated with prognosis and therapy response of patients. Recently, we report that RITA is tightly correlated with migration/invasion of breast cancer cells by affecting the turnover of focal adhesions and dynamics of the cytoskeleton. The precise molecular mechanisms remain however undefined. Interestingly, RITA is associated with the lipoma preferred partner (LPP), an important player in migration and invasion of breast cancer cells. With this proposal, we will investigate how RITA affects the motility of breast cancer cells and its significance in breast cancer development. In particular, using CRISPR/Cas9 RITA knockout/in cell lines, RITA knockdown/knockout mouse fibroblasts, fluorescence recovery after photo-bleaching, living cell imaging, transcriptomic analysis, primary breast cancer tissues as well as other molecular/biochemical/cellular methodology, we would like to address following issues: 1. The molecular mechanisms by which RITA affects migration and invasion of breast cancer cells 2. The expression levels of RITA and LPP in primary breast cancer tissues. 3. Correlation of the RITA expression with tumor microenvironment and clinical parameters of breast cancer patients. Given the crucial roles of RITA in regulating microtubule dynamics and its involvement in oncogenesis, this study will provide the molecular mechanisms by which deregulated RITA affects breast cancer development, therapy response and prognosis of breast cancer patients.

• DFG Programme: Research Grants