HELLS and osteosarcoma: Given that RB1 loss in osteosarcoma patients is associated with poor prognosis, we hypothesized that loss of RB potentiates osteosarcoma through transcriptional deregulation of chromatin remodeling genes including HELLS. Initial analysis of The Cancer Genome Atlas (TCGA) data set of 263 sarcoma tumor samples indicated that HELLS is upregulated by 4.27-fold compared to normal controls, making HELLS an attractive target to study in osteosarcoma (Figure 2A).