posted on 2023-04-03, 16:45authored bySha Jin, Wei-Chun Lee, Daniela Aust, Christian Pilarsky, Nils Cordes
<p>Supplementary Figure 1. Flowchart of high throughout screen (3D HTesiRNAS) in 3D PDAC organoids. Supplementary Figure 2. β8 integrin expression in cell fractions. Supplementary Figure 3. β8 integrin knockdown also radiosensitizes 2D PDAC cell cultures. Supplementary Figure 4. Co-immunofluorescence staining of β8 integrin with GM130, mitotracker, αV integrin, APPL2 and Caveolin. Supplementary Figure 5. Impact of αV integrin expression on survival of patients with PDAC. Supplementary Figure 6. Cytotoxicity of Gemcitabine, chloroquine, colchicine and paclitaxel in BxPC cells. Supplementary Figure 7. β8 integrin and LC3B double staining upon β8 integrin knockdown. Supplementary Table 1. Data of high-throughput esiRNA knockdown screen of 117 focal adhesion proteins in 3D PDAC cell culture. RLUC was the control. Supplementary Table 2. Classification of proteins of the β8 integrin interactome based on raw data of sequential immunoprecipitation-mass spectrometry using PANTHER database</p>
Funding
European Union's Horizon 2020 research and innovation
Pancreatic ductal adenocarcinoma (PDAC) stroma, composed of extracellular matrix (ECM) proteins, promotes therapy resistance and poor survival rate. Integrin-mediated cell/ECM interactions are well known to control cancer cell survival, proliferation, and therapy resistance. Here, we identified β8 integrin in a high-throughput knockdown screen in three-dimensional (3D), ECM-based cell cultures for novel focal adhesion protein targets as a critical determinant of PDAC cell radiochemoresistance. Intriguingly, β8 integrin localizes with the golgi apparatus perinuclearly in PDAC cells and resection specimen from PDAC patients. Upon radiogenic genotoxic injury, β8 integrin shows a microtubule-dependent perinuclear-to-cytoplasmic shift as well as strong changes in its proteomic interactome regarding the cell functions transport, catalysis, and binding. Parts of this interactome link β8 integrin to autophagy, which is diminished in the absence of β8 integrin. Collectively, our data reveal β8 integrin to critically coregulate PDAC cell radiochemoresistance, intracellular vesicle trafficking, and autophagy upon irradiation.
This study identified β8 integrin as an essential determinant of PDAC cell radiochemosensitivity and as a novel potential cancer target.