Background: The long noncoding RNA X-inactive specific transcript (XIST ) was reported to play vital roles in tumor progression. In the present study, we determined the regulatory function of XIST  in papillary thyroid carcinoma (PTC).
Materials and methods: XIST  expression was determined in PTC tissues and cell lines by quantitative real-time polymerase chain reaction (PCR) (qRT-PCR). Cellular proliferation, migration, and invasion were measured using the Cell Counting Kit-8 (CCK-8) assay, wound-healing assay, and transwell invasion assay, respectively. Western blotting was used to determine protein expression. The downstream target miRNAs for XIST  were identified by luciferase reporter assay and qRT-PCR.
Results: Relative expression of XIST  was upregulated in PTC tissues and cell lines. High XIST  expression was positively correlated with TNM stage and lymph node metastasis. Function assay demonstrated that knockdown of XIST  significantly decreased cell proliferation, migration, and invasion in PTC cells. Moreover, we showed that the effects of XIST  on PTC cell progression were mediated by miR-141.
Conclusion: Our results demonstrated that XIST  functioned as an oncogene in PTC progression by regulating miR-141, suggesting that XIST  might be a promising therapeutic target for PTC treatment.
Keywords: papillary thyroid carcinoma, XIST , miR-141, proliferation