Background: The incidence and mortality of colorectal cancer (CRC) are rising worldwide. Long-noncoding RNAs (lncRNAs) are known to play key roles in the development of human cancers, including CRC. However, the function and underlying mechanism of long intergenic noncoding RNA 00707 (LINC00707) in the development of CRC are unknown.
Materials and methods: The expression of LINC00707 and miR-206 in tissue samples or cell lines was measured by quantitative reverse transcription PCR (qRT-PCR). The protein expression of neurogenic locus notch homolog protein 3 (NOTCH3) and transmembrane 4 L6 family member 1 (TM4SF1) was assessed by Western blotting. Cell proliferation, migration, and invasion were assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and transwell assays. Luciferase reporter assay and biotin-coupled miRNA capture assay were used to explore the relationship between LINC00707 and miR-206 expression.
Results: The expression of LINC00707 was significantly upregulated in CRC tissues as compared with the adjacent non-CRC tissues. LINC00707 expression was significantly correlated with tumor size, lymphatic metastasis, and distant metastasis, but not significantly correlated with age and gender. Knockdown of LINC00707 expression significantly inhibited LoVo and HCT116 cell proliferation, migration, and invasion. LINC00707 acted as a molecular sponge by competing for miR-206 and indirectly modulating the expression of its targets, NOTCH3 and TM4SF1.
Conclusion: LINC00707 promotes CRC cell proliferation and metastasis by sponging miR-206, suggestive of its potential application for CRC treatment.
Keywords: long intergenic noncoding RNA 00707, colorectal cancer, miR-206, NOTCH3, TM4SF1