Tumor suppressor properties of the splicing regulatory factor RBM10.

RBM10 is an RNA binding protein and alternative splicing regulator frequently mutated in lung adenocarcinomas. Recent results indicate that RBM10 inhibits proliferation of lung cancer cells by promoting skipping of exon 9 of the gene NUMB, a frequent alternative splicing change in lung cancer generating a negative regulator of Notch signaling. Complementing these observations, we show that knock down of RBM10 in human cancer cells enhances growth of mouse tumor xenografts, confirming that RBM10 acts as a tumor suppressor, while knock down of an oncogenic mutant version of RBM10 reduces xenograft tumor growth.