RBM4 controls various types of splicing in a sequence-specific manner
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RBM4 regulates various cancer-related genes and suppresses tumorigenesis
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RBM4 inhibits cancer by antagonizing oncogenic SRSF1 and regulating Bcl-x splicing
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RBM4 is reduced in cancer patients and correlates positively with improved survival
Summary
Splicing dysregulation is one of the molecular hallmarks of cancer. However, the underlying molecular mechanisms remain poorly defined. Here we report that the splicing factor RBM4 suppresses proliferation and migration of various cancer cells by specifically controlling cancer-related splicing. Particularly, RBM4 regulates Bcl-x splicing to induce apoptosis, and coexpression of Bcl-xL partially reverses the RBM4-mediated tumor suppression. Moreover, RBM4 antagonizes an oncogenic splicing factor, SRSF1, to inhibit mTOR activation. Strikingly, RBM4 expression is decreased dramatically in cancer patients, and the RBM4 level correlates positively with improved survival. In addition to providing mechanistic insights of cancer-related splicing dysregulation, this study establishes RBM4 as a tumor suppressor with therapeutic potential and clinical values as a prognostic factor.