biostudies-literatureUnknown15(9)Lu WCancer stem cells (CSCs) may contribute to tumor initiation, distant metastasis and chemo-resistance. One of RNA-binding proteins, Quaking (QKI), was reported to be a tumor suppressor. Here we showed that reduced QKI levels were observed in many human oral cancer samples. Moreover further reduction of QKI expression in CSCs was detected compared with non-CSCs in oral cancer cell lines. Overexpressing QKI in oral cancer cells significantly reduced CSC sphere formation and stem cell-associated genes. In tumor implanting nude mice model, QKI significantly impeded tumor initiation rates, tumor sizes and lung metastasis rates. As a contrast, knocking down QKI enhanced the above effects. Among the putative CSC target genes, SOX2 expression was negatively affected by QKI, mechanism study revealedCancer biology & therapy1174-84https://www.ebi.ac.uk/biostudies/studies/S-EPMC4128860biostudies-literatureQKI impairs self-renewal and tumorigenicity of oral cancer cells via repression of SOX2.PMC4128860Wei MYang GLiu YLu WLu XLu HWang SLei XLu ZFeng FXu JWang LfalseQKI impairs self-renewal and tumorigenicity of oral cancer cells via repression of SOX2.Cancer stem cells (CSCs) may contribute to tumor initiation, distant metastasis and chemo-resistance. One of RNA-binding proteins, Quaking (QKI), was reported to be a tumor suppressor. Here we showed that reduced QKI levels were observed in many human oral cancer samples. Moreover further reduction of QKI expression in CSCs was detected compared with non-CSCs in oral cancer cell lines. Overexpressing QKI in oral cancer cells significantly reduced CSC sphere formation and stem cell-associated genes. In tumor implanting nude mice model, QKI significantly impeded tumor initiation rates, tumor sizes and lung metastasis rates. As a contrast, knocking down QKI enhanced the above effects. Among the putative CSC target genes, SOX2 expression was negatively affected by QKI, mechanism study revealed2014-01-01T00:00:00Z2014 Sep2025-04-22T18:00:37.627Z2019-03-27T01:33:50ZS-EPMC41288602491858110.4161/cbt.29502