BCL2L1 and neoplasm: Our results are consistent with a subsequent study showing that the incidence of invasive islet tumours was reduced in mice harbouring pancreatic β-cell-specific knockout of Bcl-x (for both Bcl-xL and Bcl-xS), and that the tumour cells lacking Bcl-x were impaired in invasion in vitro under conditions mimicking hypoxia13.