Here, we provided compelling evidence to demonstrate that SRSF9 is a proto-oncogene: (i) SRSF9 is frequently overexpressed in a wide range of tumour types; (ii) SRSF9 overexpression is able to transform NIH3T3 cells to form colonies in vitro and to form tumours in nude mice; (iii) down-regulation of SRSF9 in colon cancer cell lines reduced their colony formation ability. The gene discussed is SRSF9; the disease is neoplasm.