Long noncoding RNA PVT1 predicts poor prognosis and promotes the progression of colorectal cancer through the miR-24-3p/NRP1 axis in zebrafish xenografts.

Long noncoding RNAs (lncRNAs) play important roles in the progression of human cancer. It is reported that lncRNA plasmacytoma variant translocation 1 (PVT1) is involved in colorectal cancer (CRC), however, the underlying mechanism remains to be explored deeply, especially by in vivo models. In the present study, bioinformatics analysis showed that the expression level of PVT1 was upregulated in CRC tissues and highly associated with poor prognosis of CRC patients. In cultured CRC cells, knockdown of PVT1 inhibited cell proliferation and migration of CRC cells, while overexpression of PVT1 promoted the progression of CRC cells. In zebrafish xenografts, the silencing of PVT1 also suppressed the growth and metastasis of CRC cells. For mechanism studies, the binding relationships among PVT1, miR-24-3p, and Neuropilin 1 (NRP1) were predicted by starBase firstly. The luciferase reporter assays verified that PVT1 and NRP1 could bind with miR-24-3p directly. Further studies showed miR-24-3p negatively regulated the progression of CRC cells, the inhibition of miR-24-3p counteracted the repression effects of CRC progression when knocking down PVT1. In addition, the expression of NRP1 was regulated by PVT1, and NRP1 overexpression could partially rescue the inhibition effects of CRC progression when knocking down PVT1 in vitro and in vivo. Our study reveals that PVT1 promotes the proliferation and metastasis of CRC via regulating the miR-24-3p/NRP1 axis, which provides a prognosis biomarker and a potential therapeutic target for CRC patients.