Expression of PTEN regulated by PTENp1 as a "sponge" adsorbed by miR-21 in oral squamous cell carcinoma / 西安交通大学学报(医学版)

ABSTRACT

Objective: To explore the role of the new regulator pseudogene phosphatase and tensin homolog pseudogene 1 (PTENp1) in the regulation of PTEN mRNA and gene expression in oral squamous cell carcinoma (OSCC) so as to provide a new target for the prevention, treatment and outcome of OSCC. Methods: First, we collected 42 specimens of OSCC and normal tissues, extracted RNA, detected the expressions of PTENp1, PTEN and miR-21 by qRT-PCR, and studied their correlation by Pearson correlation analysis. HEK293 cells were cultured and transfected with luciferase plasmid of 3'UTR of PTEN and mimic or inhibitor of miR-21 or full-length PTENp1 3'UTR plasmid, respectively. The regulatory role of PTENp1 in PTEN-miR-21 axis and its cancer promoting function were verified by luciferase activity test. Results: qRT-PCR showed that the expressions of PTEN (85.7%) and PTENp1 (90.4%) were significantly repressed in the OSCC tissues while miR-21 expression (76.2%) was remarkably increased. Pearson correlation analysis showed that PTEN expression was negatively correlated with miR-21 expression (R=0.123 5, P<0.001) but positively correlated with PTENp1 expression (R=0.051 8, P=0.01). The results of luciferase activity showed that PTEN expression was significantly up-regulated by overexpression of PTENp1, suggesting that PTENp1 could target competitive binding miR-21 to regulate PTEN expression. Results: PTENp1, as the ceRNA of PTEN, competitively binds the miR-21, which provides a new idea for predicting the early marker and targeting therapy of OSCC in the future.