In immunocompetent SCLC murine models obtained by conditional loss of TRP53, p130 and RB1 (called RPP) or TRP53, RB1 and MYC (called RPM), they observed that co-treatment with WEE1 inhibitor and PD-L1 antibody induces strong infiltration of CD3+, CD8+, CD44+ effector/memory T-cell and M1 macrophage populations, and complete tumour regression. Here, TP53 is linked to neoplasm.