To investigate the impact of STAT3 inhibition and immune checkpoint blockade (ICB) on the suppressive elements of the PDAC tumour microenvironment, mT4 tumours were orthotopically implanted into syngeneic C57BL/6 mice and treated with ICB with anti-CTLA-4 and anti-PD-1 antibodies combined with STAT3 or control ASO. This evidence concerns the gene CTLA4 and neoplasm.