To investigate whether TRIM59 regulates invasion and metastasis of nasopharyngeal carcinoma cells by targeting PPM1B.
We analyzed the expression of TRIM59 in nasopharyngeal carcinoma tissues based on data from TCGA database and detected the expressions of TRIM59 and PPM1B in nasopharyngeal carcinoma and adjacent tissues using Western blotting. We also detected the expressions of TRIM59 and PPM1B at both the mRNA and protein levels in nasopharyngeal carcinoma cell lines using RT-PCR and Western blotting. Stable cell lines with TRIM59 overexpression or knockdown were established in HNE1 cells, in which the targeting relationship between TRIM59 and PPM1B was analyzed using Western blotting and a luciferase reporter gene assay. Transwell chamber assay was used to assess changes in the invasion and migration abilities of HNE1 cells with TRIM59 overexpression or knockdown.
Analysis based on TCGA database showed that TRIM59 expression was significantly higher in nasopharyngeal carcinoma tissues than in adjacent tissues (=0.006); the expression of TRIM59 increased (=0.01) and PPM1B expression decreased significantly (=0.03) in nasopharyngeal carcinoma tissues. Compared with HNEpC cells, HNE1 cells expressed a significantly higher level of TRIM59 (=0.04) but a lower level of PPM1B (=0.01). Luciferase reporter gene assay indicated that PPM1B was a downstream target gene of TRIM59 and its expression was negatively correlated with TRIM59 expression (=0.01). In HNE1 cells, TRIM59 overexpression significantly promoted cell invasion (=0.01) and migration (=0.02) while TRIM59 knockdown obviously suppressed cell invasion (=0.01) and migration (=0.01). TRIM59 knockdown with simultaneous PPM1B overexpression more strongly inhibited invasion (=0.02) and migration (=0.01) of HNE1 cells as compared with TRIM59 knockdown alone.
TRIM59 regulates invasion and migration of nasopharyngeal carcinoma cells through targeted modulation of PPM1B.