Long non-coding RNAs (lncRNAs) have been shown to have crucial regulatory roles in human cancer biology. LncRNA PANDAR is a novel identified lncRNA that was previously reported to be increased in various cancers; however, its effect in colorectal cancer (CRC) remains unknown. The aim of this study was to explore the expression and role of lncRNA PANDAR in CRC.
The expression of lncRNA PANDAR was examined in CRC samples and cell lines by qRT-PCR. Kaplan-Meier survival analysis and univariate and multivariate Cox proportional hazards model were performed to evaluate the clinical and prognostic significance of lncRNA PANDAR in CRC patients. Furthermore, the biological function of lncRNA PANDAR on tumor cell growth, apoptosis and mobility was investigated through CCK-8, soft agar colony formation, flow cytometry, transwell migration and invasion assays in vitro. The potential mechanism of lncRNA PANDAR was demonstrated by Western blot and qRT-PCR.
The expression level of PANDAR was higher in CRC tissues and cells compared to adjacent non-tumor tissues and normal colonic epithelial cells. Patients with high PANDAR expression level had poorer overall survival than those with low PANDAR expression. Moreover, multivariate analysis showed that the status of PANDAR expression was an independent prognostic indicator for CRC. Knockdown of PANDAR could inhibit cell growth, migration and invasion, arrest cell cycle as well as induce apoptosis of CRC cells in vitro study. In addition, PANDAR could affect epithelial-mesenchymal transition through inhibiting N-cadherin, vimentin, β-catenin, Snail and Twist expression and increasing the expression levels of E-cadherin.
LncRNA PANDAR expression is increased in colorectal cancer and associates with overall survival in colorectal cancer patients
a Relative expression of PANDAR in 124 pairs of colorectal cancer tissues and adjacent non-tumor tissues by qRT-PCR analysis. ***P < 0.001 compared with non-tumor control. b The expression levels of PANDAR in a panel of colorectal cancer cell lines were determined by qRT-PCR and compared with that in human colonic epithelial cells (HcoEpiC). **P < 0.01 compared with the HcoEpiC cell. c Kaplan–Meier overall survival curves for two groups defined by low and high expression of PANDAR in patients with colorectal cancer (P = 0.0031 < 0.01). d qPCR analysis of PANDAR expression levels following the treatment of SW480 and LoVo cells with siRNAs against PANDAR. Data represent the mean ± SD from three independent experiments. *P < 0.05 compared with Si-NC; **P < 0.01 compared with Si-NC
These data suggested that lncRNA PANDAR was a novel molecule involved in CRC progression, which provided a potential prognostic biomarker and therapeutic target for new therapies in patients with CRC.