Long Non-coding RNA PVT1 Functions As an Oncogene in Human Colon Cancer Through MiR-30d-5p/RUNX2 Axis

Purpose: Recently, long noncoding RNAs (lncRNAs) have caught more attention for their role in tumor progression. Colon cancer is one of these ordinary malignant tumors. This study aimed to identify how lnc RNA PVT1 affects the progression of colon cancer.

Methods: PVT1 expression of both colon cancer cell tissue and 60 paired cancer and peri-tumoral tissue samples was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The associations between lnc RNA PVT1 expression level and clinicopathological characteristics and patients' disease-free survival rate were evaluated. Furthermore, function assays containing cell proliferation assay, colony formation and transwell assay were conducted. Mechanism-associated experiments included western blot assay, luciferase assay and RNA immunoprecipitation assay.

Results: PVT1 expression was significantly higher in tumor tissues than in peritumoral tissues, and was associated with lymph node metastasis, tumor stage and survival time of these patients. Moreover, knockdown of PVT1 promoted tumor growth and invasion in vitro. In addition, further experiments revealed that miR-30d-5p was a direct target of PVT1 and its expression in tumor tissues negatively correlated to PVT1 expression. Moreover, RUNX2 was identified as the direct target spot of miR-30d-5p according to the mechanism experiments. Besides, RUNX2 expression was positively correlated with PVT1 in cancer tissues and cells.

Conclusions: These results indicate that PVT1 could promote metastasis and proliferation of colon cancer via suppressing miR-30d-5p/RUNX2 axis, which may offer a new way for interpreting the mechanism of colon cancer development.