Selenium Mediated MicroRNA-29a-3p Regulates Invasion And Migration By Targeting COL4A2 In LMH Cells

Selenium(Se)is an essential trace element that has an important influence on human health.Se has a wide range of biological properties,including anti-cancer function.A large number of studies have pointed out that Se supplement can effectively reduce the risk of cancer.The migration and invasion of cancer cells are the main causes of death in cancer patients.As a non-coding RNA,microRNA(miRNA)play an important role in cell proliferation,differentiation,apoptosis,and tumorigenesis by targeting the post-transcriptional repression of the target gene,thereby regulating body's different biological responses.Studies have shown that miRNAs are involved in occurrence and development of cancer by regulating metastasis-related factors.In recent years,some studies have shown that changes of Se content can alter the expression of related miRNAs.However,the mechanism of Se-mediated miRNA regulation of cancer migration and invasion has not been elucidated.Therefore,on the basis of the pre-laboratory miRNA genome analysis,Se-specific miR-29a-3p was selected in this experiment,using dual luciferase reporter gene detection system and real-time quantitative PCR(qRT-PCR)and Western Blot(WB).Flow cytometry and MTT assay were used to detect cell proliferation,transwell assay and wound healing assay were used to detect cell invasion and migration.The results shows as follows:(1)Based on the lab pre-study of selenium regulation network of miRNAs,a miRNA miR-29a-3p with a significantly different expression in the selenium-deficient state was screened for bioinformatics prediction,qRT-PCR,WB and dual luciferase reporting.Genetic methods,analysis and screening of their potential target genes,combined with KEGG pathway enrichment information,finally predicted and successfully verified the relationship between miR-29a-3p and its target gene COL4A2(2)In the absence of selenium,miR-29a-3p is up-regulated in LMH cells and its target gene COL4A2 is down-regulated,thereby activating RhoA/ROCK pathway,PTEN,and SRC are down-regulated,and RhoA,ROCK1,MLC1,and Actnin are up-regulated.The above results indicate that over-expression of miR-29a-3p can target COL4A2,activate RhoA/ROCK pathway,and promote the invasion and migration of LMH cells.(3)The results of flow cytometry showed that over-expression of miR-29a-3p can promote G1/S phase transition and thus enhance the proliferation of LMH cells.Transwell and wound healing experiments showed that miR-29a-3p over-expression can enhance the ability of migration and invasion of LMH cells.Selenium can hinder the proliferation,migration and invasion of LMH cells induced by over-expression miR-29a-3p.4)Based on miR-29a-3p over-expression and knockdown model in LMH cells,Se supplement could hinder the metastasis induced by over-expression miR-29a-3p,also RhoA inhibitor fasudil added can cut off the RhoA/ROCK pathway to achieve the same effect.