Colorectal cancer (CRC) is associated with high morbidity rates. Long non‑coding RNAs (lncRNAs) participate in the development of CRC. However, the potential roles of lncRNA plasmacytoma variant translocation 1 (PVT1) in CRC remain unknown. Therefore, the aim of the present study was to investigate the potential roles of PVT1 in CRC. Reverse transcription‑quantitative PCR and western blot analyses were conducted to determine the mRNA and protein expression levels. The cellular behaviors were detected using 5‑Ethynyl‑2'‑deoxyuridine, Cell Counting Kit‑8 and flow cytometry assays. The interaction between PVT1 and microRNA (miR)‑761 or MAPK1 was confirmed using a dual‑luciferase reporter assay. Moreover, the Pearson's method was applied for correlation analysis. The results demonstrated that the expression levels of PVT1 and MAPK1 were upregulated, while miR‑761 was downregulated in CRC tissues. The expression of PVT1 was positively correlated with MAPK1 and negatively correlated with miR‑761. In addition, PVT1 sponged miR‑761 to upregulate MAPK1 expression. It was found that the knockdown of PVT1 expression inhibited the proliferation and promoted the apoptosis of CRC cells, which was more potent in cells transfected with miR‑761. The regulatory role of small interfering RNA‑PVT1 on the expression of apoptosis‑related genes was reduced by MAPK1. Collectively, the present results suggested that knockdown of PVT1 may inhibit the progression of CRC by regulating the miR‑761/MAPK1 axis, which may provide a promising biomarker for the treatment of CRC.
Keywords: MAPK1; apoptosis; colorectal cancer; long non‑coding RNA plasmacytoma variant translocation; microRNA‑761; proliferation.