HELLS and retinoblastoma: For example, Benavente et al. found that HELLS was tumorigenic only when upregulated in the tumor cell of origin and that HELLS upregulation epigenetically mediated the aberrant expression of genes that drive retinoblastoma tumorigenesis while a recent finding in osteosarcoma found that HELLS is non-essential for tumorigenesis in this cancer39,81.