Broadening Adenoviral Oncolysis in PDAC: Interrogation of Patient-Derived Organoids for personalized virotherapy and modulation of miRNA content to boost adenoviral potency

The general goal of this thesis has been to progress oncolytic adenovirus therapy for PDAC, by the incorporation of novel preclinical models to test for patient-specific responses and the generation of oncolytic adenoviruses with enhanced therapeutic index. The two main objectives have been the following: i) Evaluate patients-derived organoids (PDOs) technology as a platform to screen for personalized virotherapy in vitro 1) Establishment of a battery of PDOs from PDAC and normal pancreatic tissues, and evaluation of their applicability in the study of adenoviral infection; 2) Screening of a battery of PDOs to identify individual sensitivities to virotherapies, and the effects derived from the combination with chemotherapy; 3) Study virotherapy-responses in metastasis originated from PDOs xenografted in mice; (ii) Improve oncolytic adenovirus potency by modulation of miRNAs deregulated in PDAC 4) Screening of aberrantly expressed miRNAs sensitizing viral oncolysis in PDAC via CRISPR/Cas9 system; 5) Generation of a miRNA sponge-adenovirus and evaluation of its oncolytic effects in vitro and in vivo; 6) Modulation of miRNA levels with the THZ1 transcriptional inhibitor, and assessment of the effects of its combination with oncolytic adenoviruses.