Silencing of TRIM11 suppresses the tumorigenicity of chordoma cells through improving the activity of PHLPP1/AKT

BACKGROUND: Tripartite motif-containing protein 11 (TRIM11), a member of RING family of E3 ubiquitin ligases, is identified as an oncogene in certain human tumors. However, the detailed biological function of TRIM11 in chordoma is still unclear. The purpose of present research is to explore the role of TRIM11 in human chordoma cells. METHODS: TRIM11 was induced silencing and overexpression in human chordoma cells using RNA interference (RNAi) and lentiviral vector. qRT-PCR and western blot were used to determine gene expression in chordomas cells. Meanwhile, cell counting kit-8 (CCK-8) assay was used to examine the cell proliferation rate. Flow cytometry analysis was performed to quantify the cell apoptosis rate. RESULTS: We identified that TRIM11 was upregulated in chordomas tissues. Moreover, TRIM11 presented pro-proliferation and anti-apoptosis function in chordoma cells. Further, LY294002, a specific AKT inhibitor, was utilized to examine the connection between TRIM11 and AKT in human chordoma cells. Importantly, our findings elucidated that TRIM11 promoted the growth of chordoma cells and involved in AKT signaling. Much more importantly, knockdown of TRIM11 significantly upregulated the translation of PH domain leucine-rich repeats protein phosphatase 1 (PHLPP1), whereas did not affect its transcription. Results that obtained from co-immunoprecipitation (Co-IP) and ubiquitination assay demonstrated TRIM11 interacted with PHLPP1 and promoted its ubiquitination in chordoma cells. Moreover, overexpression of PHLPP1 inhibited the phosphorylation of AKT in human chordomas cells. These results suggested that TRIM11 mediated the post-translation modification of PHLPP1 and was a novel component in PHLPP1/AKT signaling pathway in human chordoma cells. CONCLUSIONS: Taken together, the present research not only enhanced the understanding of TRIM11 but also indicated its potential target and signaling pathway in human chordoma cells. Trial registration retrospectively registered.