Long Noncoding RNA PRRG4-4 Promotes Viability, Cell Cycle, Migration, and Invasion in Lung Cancer Cells.

There is a perception that long noncoding RNA (lncRNA) has relationship with carcinogenesis. Many studies have previously identified and validated that the section of chromosome 11p13 is associated with high incidence of tumor. In this study, we investigated a new lncRNA, named lncPRRG4-4, mapped to 11p13 and suspected that lncPRRG4-4 was a potential lung cancer-related gene. To explore its role in carcinogenesis, we first demonstrated that lncPRRG4-4 was upregulated in lung cancer tissues compared with adjacent nontumor tissues and functioned as an oncogene in lung cancer cells. The lncPRRG4-4 was significantly upregulated in lung cancer tissues compared with adjacent normal counterparts (mean +/- standard deviation: 0.12 +/- 0.84 vs. 0.05 +/- 0.22; p < 0.001). Patients with metastasis exhibited high levels of lncPRRG4-4 expression than those without metastasis in both the southern samples (p = 0.045) and eastern samples (p = 0.030), total samples (p = 0.004). In addition, downregulation of lncPRRG4-4 expression inhibited lung cancer proliferation, viability, migration, and invasion ability, arrested cell cycle, facilitated apoptosis, and vice versa. Taken together, these observations suggested that the lncPRRG4-4 functions as an oncogene in lung cancer cells.