The specificity of gliotoxin was demonstrated in the well differentiated HCC cell line Huh7 (Hayashi et al., 2015) and in the breast cancer derived cell line MDA-MB-468, which did not display a detectable nuclear NOTCH/CSL activity and which were found to be resistant to gliotoxin treatment in vitro. The gene discussed is RBPJ; the disease is hepatocellular carcinoma.