Abstract: Objective To investigate whether LINC01123 promotes colorectal cancer (CRC) cell proliferation through regulating the miR-625-5p/LASP1 signaling axis. Methods SSW480 cells were cultured, and and then divided into sh-NC, sh-LINC01123 and sh-LINC01123+miR-625-5p inhibitor groups. An in vivo xenograft tumor model was established in nude mice, and the tumor volume and tumor weight were detected. HE staining was used to detect the pathological changes of tumor tissues, TUNEL staining was used to detect cell apoptosis, and immunohistochemical(IHC) assay was used to detect the expressions of Ki-67 and LASP1 proteins in nude mouse tumor tissues. The mRNA expressionsof LINC01123, miR-625-5p and LASP1 were detected by RT-qPCR, and the protein expressions of LINC01123 and LASP1 were detected by Western blot. Results Compared with the sh-NC group, the sh-LINC01123 group showed significantly decreased tumor volume, expression of Ki-67 and LASP1 protein, mRNA levels of LINC01123 and LASP1 in sh-LINC01123 group were significantly decreased (P＜0.05). Tumor tissue structure was severely disrupted, with widespread cell pyknosis and necrosis. Meanwhile, the TUNEL-positive cell rate and miR-625-5p mRNA expression were significantly increased(P＜0.01). In contrast, compared with sh-LINC01123 group, tumor volume, expression of Ki-67, LASP1 protein and mRNA expression of LINC01123 and LASP1 in sh-LINC01123+miR-625-5p inhibitor group were significantly increased, and tumor tissue growth was significantly inhibited (P＜0.05), the TUNEL-positive cell rate and miR-625-5p mRNA expression were significantly decreased(P＜0.01). Conclusions LINC01123 can promote the proliferation of colorectal cancer in vivo by regulating miR-625-5p/LASP1 signaling axis.

Key words: LINC01123, miR-625-5p, LASP1, colorectal cancer, Ki-67