circCLK3 regulates colorectal cancer SW620 cell proliferation, migration, and invasion by targeting miR-654-5p

BACKGROUND

Recent studies have investigated the role of circular RNAs (circRNAs) as significant regulatory factors in the progression of multiple cancers, containing colorectal cancer (CRC). Nevertheless, the biological functions of circCLK3 in CRC and the underlying mechanisms by which it regulates CRC progression remain unclear.

AIM

To clarify the mechanism of circCLK3 regulating colorectal cancer SW620 cell proliferation, migration, and invasion.

METHODS

CRC tissues and adjacent tissues were collected, and the expression of circCLK3 and miR-654-5p was detected by qRT-PCR. SW620 cells were cultured in vitro and divided into the following groups: si-circCLK3 group, pcDNA-circCLK3 group, miR-654-5p group, si-circCLK3 + anti-miR-654-5p group, and corresponding negative control groups (si-NC group, pcDNA group, miR-NC group, and si-circCLK3 + anti-miR-NC group). CCK8 assay, colony formation test, scratch test, and Transwell test were used to detect cell proliferation, migration, and invasion. The interaction between circCLK3 and miR-654-5p was confirmed by dual-luciferase reporter assay. The protein expression of MMP-2 and MMP-9 was detected by Western blot.

RESULTS

circCLK3 expression was increased (P < 0.05), while miR-654-5p expression was decreased (P < 0.05) in CRC tissues. Cell viability, scratch healing rate, the protein levels of matrix metalloproteinase-2 (MMP-2) and MMP-9, the number of cell clones formed, and the number of invasive cells were decreased (P < 0.05) in the si-circCLK3 group. circCLK3 could negatively regulate the expression of miR-654-5p. Cell viability, scratch healing rate, the protein levels of MMP-2 and MMP-9, the number of cell clones formed and the number of invasive cells were decreased (P < 0.05) in the miR-654-5p group. Cell viability, scratch healing rate, the protein levels of MMP-2 and MMP-9, the number of cell clones formed, and the number of invasive cells were increased (P < 0.05) in the si-circCLK3 + anti-miR-654-5p group.

CONCLUSION

circCLK3 promotes CRC cell proliferation, migration, and invasion by targeting miR-654-5p.

Knockdown of miR-10a-5p inhibits gastric cancer cell growth and metastasis by targeting THBS2

BACKGROUND

Many microRNAs (miRNAs) have been found to play a role in inhibiting or promoting the pathogenesis and progression of gastric cancer (GC). However, there are a large number of miRNAs whose roles in GC are still unclear. Therefore, it is still necessary to continue screening miRNAs that affect the growth and metastasis of GC cells.

AIM

To investigate the effect of miR-10a-5p on the growth and metastasis of GC cells and the underlying mechanism.

METHODS

The expression levels of miR-10a-5p in GC tissues and GC cells (MGC-803 and AGS) were detected by real-time quantitative PCR (RT-qPCR). After transfecting miR-10a-5p-inhibitor into MGC-803 and AGS cells, the proliferation, colony formation, migration, and invasion of GC cells were detected by CCK-8 assay, colony formation assay, and transwell assay. The protein and mRNA expression levels of THBS2 in GC tissues and GC cells (MGC-803 and AGS) were detected by Western blot and RT-qPCR, respectively. The potential target genes of miR-10a-5p were predicted with TargetScan software and further verified. After NC + pcDNA-Con, miR-10a-5p inhibitor + pcDNA-Con, or miR-10a-5p inhibitor + pcDNA-THBS2 were co-transfected into MGC-803 cells, the proliferation, colony formation, migration, and invasion of MGC-803 cells were detected by CCK-8 assay, colony formation assay, and transwell assay.

RESULTS

The expression levels of miR-10a-5p were up-regulated in GC tissues as well as MGC-803 and AGS cells. Knockdown of miR-10a-5p significantly decreased the proliferation, colony formation, and migration and invasion of MGC-803 and AGS cells. THBS2 mRNA and protein levels were down-regulated in GC tissues as well as MGC-803 cells and AGS cells. THBS2 was identified to be a target gene of miR-10a-5p. Overexpression of THBS2 could reverse the inhibitory effect of miR-10a-5p knockdown on the proliferation, colony formation, migration, and invasion of MGC-803 cells.

CONCLUSION

Knockdown of miR-10a-5p inhibits the growth and metastasis of GC cells by targeting THBS2.