The Function And Mechanism Of Colon Cancer Exosomes LncRNA KCNQ1OT1 In Colon Cancer Cells

Objective:Verify the expression of lncRNA KCNQ1OT1 in the exosomes of colon cancer cells.Clarify the function of lncRNA KCNQ1OT1 in colon cancer cells HCT-116 and HT-29,and explore the molecular mechanism of its role in colon cancer cellsMethods:Exosomes were isolated and purified by ?ltracentrifugation and Identificated using high-resolution projection electron microscopy.Western Blot was used to verify exosome marker protein.RNA from exosomes and colon cancer cells were extracted for reverse transcription and PCR amplification,the PCR products were subjected to agarose gel electrophoresis to verify the expression of KCNQIOT1 in exosomes.KCNQIOT1 overexpression plasmid and blank control were transfected in colon cancer cell lines HCT-116 and HT-29,and they were knockdown by siRNA and blank control also.Cell?lar functional experiments were conducted in above groups,including CCK8 proliferation test,scratch test,Transwell migration and invasion test so as to verify the effect of lncRNA KCNQIOT1 on cell function.RNA immune Precipitation(RIP)experiment and double luciferase labeling experiment were applied to verify the specific binding between KCNQIOT1 and miR-125a-5p and the binding between miR-125a-5p and SMURF1.After overexpression and knockdown of KCNQ1OT1 and miR-125a-5p,the expression of SMURF1 was verified by Western Blot,for verifying their reg ? latory function on SMURF1.Rescue experiments were performed,by detecting the expression of SMURF1 after KCNQIOT1 and miR-125a-5p were transfected together and were knocked down together.Results:Exosomes co?ld be isolated and observed in the supernatant of colon cancer cell c?lture,and the expression of KCNQIOT1 was found in exosomes.In colon cancer HCT-116 and HT-29 cells,overexpressed KCNQIOT1 co?ld promote the proliferation,migration and invasion After knockdown of KCNQ1OT1,the proliferation,migration and invasion of colon cancer cells were inhibited.miR-125a-5p cco?ld specifically bind to both KCNQ1OT1 and SMURF 1.Overexpression of KCNQ10T1 promoted the expression of SMURF1,while knockdown of KCNQ10T1 inhibited the expression of SMURF1,.Overexpression of miR-125a-5p inhibited the expression of SMURF1,and knockdown of miR-125a-5p promoted the expression of SMURF1.Overexpression of miR-125a-5p on the basis of overexpression of KCNQ10T1 co?ld significantly inhibit the expression of SMURF1,while knockdown of miR-125a-5p expression on the basis of knockdown of KCNQ10T1 co?ld promote the expression of SMURF1.Conclusion:KCNQ1OT1 is present in exosomes isolated from the supernatant of colon cancer c?lture.FCGNQ1OT1 promotes the proliferation,migration and invasion of colon cancer cells by reg?glating the KCNQ10T1-miR-125a-5p-SMURF1 axis.