Linc00887 suppresses tumorigenesis of cervical cancer through regulating the miR-454-3p/FRMD6-Hippo axis

Background: Emerging evidence suggested that long intergenic noncoding RNA (lincRNA) 00887 (NR_024480) reduced the invasion and metastasis of non-small cell lung cancer by sponging miRNAs degradation. However, the role and regulatory mechanism of linc00887 in the progression of cervical cancer remain largely unknown.

Methods: In vivo or vitro, RT-qPCR assay was used to detect the expression of linc00887 in human normal (N = 30), cervical cancer tissues (N = 30), human normal cervical epithelial cells (Ect1/E6E7) and cervical cancer cell lines (HeLa, C33A). Then, CCK-8 and Transwell assays were used to examine cell proliferation and invasion when linc00887 was overexpressed or knocked down. In addition, bioinformatics, luciferase reporter gene and pull-down assays were used to predict and validate the relationship between linc00887 and miR-454-3p. Moreover, we detected the expression of miR-454-3p in Ect1/E6E7, HeLa and C33A cells when linc00887 was overexpressed or knocked down. Cell proliferation and invasion were also measured when pcDNA-linc00887 and miR-454-3p were transfected alone or together. Next, miR-454-3p target gene was predicted and validated by bioinformatics and luciferase reporter gene assays. Gain- and loss-of-function experiments were performed in HeLa cells to evaluate the effect of miR-454-3p or linc00887 on the expression of FERM domain containing protein 6 (FRMD6) protein and several key proteins in the FRMD6-Hippo signaling pathway.

Results: Linc00887 was downregulated in cervical cancer tissues or human cervical cancer cell lines (Hela, C33A) compared with normal tissues or cell lines. Overexpression of linc00887 inhibited proliferation and invasion HeLa and C33A cells, while linc00887 knockdown had the opposite effect. Linc00887 bound with miR-454-3p, and overexpression of miR-454-3p rescued linc00887-induced inhibition proliferation and invasion of HeLa cells. MiR-454-3p targeted and suppressed the expression of FRMD6, and linc00887 suppressed tumorigenesis of cervical cancer through activating the FRMD6-Hippo signaling pathway.

Conclusions: Linc00887, sponging miR-454-3p, inhibited the progression of cervical cancer by activating the FRMD6-Hippo signaling pathway.