Experimental Study Of Lnc SNHG1 Targeting MiR-101 On Proliferation,Apoptosis,Invasion And Migration Of Breast Cancer Cells

Objective:To detect the expression of Lnc SNHG1（SNHG1）in breast cancer tissues and adjacent tissues.Down-regulate the expression of SNHG1in breast cancer cells by shRNA technology,so as to clarify the role of SNHG1 in proliferation,apoptosis,invasion and migration of breast cancer cells and the mechanism of targeted regulation.This study was not only conducive to the future study of the role of SNHG1 in breast cancer,it can find new targets for future research on molecular mechanism of breast cancer.Methods:1.The expression of SNHG1 in breast cancer tissues and their adjacent tissues were detected by qRT-PCR.2.Cell culture medium containing 10%fetal bovine serum,streptomycin（100U/mL）and penicillin（100U/mL）was used to culture breast cancer cells.The parameters of cell culture were saturated humidity,37℃and 5%CO₂concentration.All experimental cells were in logarithmic growth phase and in good condition.Cell passage was digested with trypsin containing 0.25%,the digestion temperature was 37℃,and the digestion time was about 1 minute.When the cells were observed under a microscope,1000g centrifugation was performed for 10 minutes.The supernatant solution was removed and the cell culture medium was added for further culture.3.SNHG1 shRNA（sh-SNHG1）and shRNA control（sh-NC）were transfected into breast cancer cells.The down-regulation effect was detected by qRT-PCR,cell proliferation was measured by MTT,cell apoptosis was measured by flow cytometry,cell migration and invasion were measured by Transwell chamber,and the expression of Cleaved Caspase-3 and MMP-2protein were measured by Western blot.4.Quantitative RT-PCR was used to detect the expression of miR-101 in breast cancer tissues and corresponding adjacent tissues,and the correlation between miR-101 and SNHG1 expression in breast cancer tissues was analyzed.5.The relationship between SNHG1 and miR-101 was predicted and analyzed by bioinformatics software,and the target relationship was identified by double luciferase reporting system.6.SNHG1 shRNA and miR-101 inhibitors（sh-SNHG1+anti-miR-101）,SNHG1 shRNA and inhibitors control（sh-SNHG1+anti-NC）were co-transfected into breast cancer cells at the same time.Cell proliferation was measured by MTT method,apoptosis was measured by flow cytometry,cell migration and invasion were measured by Transwell chamber,and Cleaved Caspase-3 and MMP-2 were measured by Western blot.7.miR-101 mimics（miR-101）and mimics control（miR-NC）were transfected into breast cancer cells.The up-regulation effect was detected by qRT-PCR,cell proliferation was detected by MTT,apoptosis was detected by flow cytometry,cell migration and invasion were detected by Transwell chamber,and expression of Cleaved Caspase-3 and MMP-2 were detected by Western blot.Results:1.The expression level of SNHG1 in breast cancer tissues was significantly higher than that in adjacent tissues（P<0.05）.2.Compared with sh-NC,the level of SNHG1 in sh-SNHG1 cells decreased significantly,cell proliferation ability decreased,cell apoptosis rate increased,the number of cell invasion and migration decreased,the level of Cleaved Caspase-3 protein increased,and the level of MMP-2 protein decreased（P<0.05）.3.The expression level of miR-101 in breast cancer tissues was significantly lower than that in adjacent tissues（P<0.05）.The expression levels of miR-101 and SNHG1 in breast cancer tissues were negatively correlated.4.Bioinformatics software predicts that SNHG1 and miR-101 have targeted binding sites.After co-transfection of SNHG1-WT and miR-101mimincs,the luciferase activity of breast cancer cells decreases,and the expression of miR-101 in sh-SNHG1 cells increases.5.Compared with sh-SNHG1+anti-NC,sh-SNHG1+anti-miR-101 cells had higher proliferation ability,lower apoptotic rate,more cell invasion and migration,lower Cleaved Caspase-3 protein level and higher MMP-2 protein level.6.Compared with miR-NC,the expression of miR-101 decreased,cell proliferation ability decreased,cell apoptosis rate increased,cell invasion and migration decreased,the expression of Cleaved Caspase-3 protein increased,and the expression of MMP-2 protein decreased in miR-101 cells（P<0.05）.Conclusions:1.SNHG1 is up-regulated in breast cancer tissues.Downregulation of SNHG1 can inhibit the proliferation,invasion and migration of breast cancer cells and induce apoptosis.2.The down-regulation of the expression of miR-101 in breast cancer tissue and up-regulation of miR-101 inhibit the proliferation,invasion and migration of breast cancer cells and induce apoptosis.3.The mechanism of SNHG1 is related to the targeting regulation of miR-101.