RBM5 and cancer: Both proteins have tumor-suppressor properties in a variety of cancer cell lines, and it has been suggested that RBM5 expression can influence RBM10. Due to their similarities, and the recent evidence that RBM10 is mutated in up to 21% of lung cancers, we hypothesized that RBM10 would share RBM5’s tumor-suppressor properties in SCLC.