Study On The Relationship Between MiR-324-5p And Breast Cancer About Cell Proliferation,Migration And Its Clinical Value

Objective:The incidence of breast cancer ranks first among female malignant tumors.The molecular mechanism of breast cancer is not fully understood,and there is a lack of effective early monitoring indicators in clinical practice.Recent studies have found that miR-324-5p is related to the occurrence and development of various tumors,but there is no clear conclusion about the specific relationship between miR-324-5p and breast cancer and whether it can be used as a biomarker for breast cancer diagnosis and prognosis.In this paper,we investigated the relationship between miR-324-5p and breast cancer cell proliferation and migration,explored the expression of miR-324-5p in tissues and serum of breast cancer patients,analyzed its relationship with clinicopathological features,and further explored its clinical value in the diagnosis and prognosis of breast cancer.methods:The effect of miR-324-5p on the proliferation ability of breast cancer cells using Cell Counting Kit-8(CCK-8)and plate cloning assays.Wound-healing assay and Transwell assay to evaluate the effect of miR-324-5p on the invasion and migration of breast cancer cells.The expression of miR-324-5p was detected by real-time quantitative polymerase chain reaction(RT-qPCR)in 38 pairs of breast cancer and adjacent tissues,100 patients’ serum and 50 normal healthy human serum samples,and analyzed its relationship with breast cancer correlation of clinicopathological features.The diagnostic value of miR-324-5p was assessed using receiver operating characteristic(ROC)curves.Kaplan-Meier method and COX regression were used to analyze the prognostic value of serum miR-324-5p expression in breast cancer.Results:1.The expression of miR-324-5p in breast cancer cells MCF-7,Hs578 T and T-47 D was significantly higher than that in human breast epithelial cells MCF-10A(p<0.01).2.After MCF-7 and Hs578 T cells were transfected with miR-324-5p mimic and inhibitor,RT-qPCR was used to verify the transfection effect.Overexpression of miR-324-5p can promote the proliferation ability of MCF-7 cells(p<0.01),and interference with miR-324-5p can inhibit the proliferation ability of Hs578 T cells(p<0.001).3.Wound healing assay and Transwell assay confirmed that up-regulation of miR-324-5p can stimulate the invasion and migration ability of MCF-7 cells(p<0.01),while inhibition of miR-34-5p expression in Hs578 T cells has the opposite effect(p<0.01).4.Compared with the adjacent tissues,the relative expression level of miR-324-5p increased in 31 of 38 breast cancer tissue samples(p<0.05).Furthermore,miR-324-5p level was higher in breast cancer patients with advanced stage compared with those in early stage(p<0.01).5.The expression of miR-324-5p was relatively elevated in 100 breast cancer serum samples compared with 50 healthy human serum samples(p<0.001).The AUC value of serum miR-324-5p expression level in the diagnosis of breast cancer was 0.7557(95%CI: 0.6797–0.8317),with good sensitivity(71%)and specificity(74%).6.In the correlation analysis of clinicopathological characteristics of breast cancer,the expression of miR-324-5p was significantly correlated with age(p=0.0278)and TNM stage(p=0.0291),but not with tumor size(p=0.8412),lymph node metastasis(p=0.3093),ER(p>0.9999),PR(p=0.1512)or HER(p=0.1614),type(p=0.6396).7.In survival analysis,patients with low miR-324-5p had significantly longer disease-free survival(DFS;p=0.0115)and overall survival(OS;p=0.0073).In addition,miR-324-5p(HR: 2.256,95% CI: 1.06–4.802,p=0.039),TNM stage(HR:3.05,95% CI: 1.421–6.548,p=0.004),and ER(HR: 0.454,95% CI: 0.225–0.915,p=0.027)were significantly correlated with DFS.miR-324-5p(HR: 2.633,95% CI:1.025–6.766,p=0.044),TNM stage(HR: 3.309,95% CI: 1.414–7.743,p=0.006),and PR(HR: 0.423,95% CI: 0.187–0.96,p=0.04)were significantly correlated with OS.Conclusions:1.In vitro functional test results showed that miR-324-5p could promote the proliferation,invasion and migration of breast cancer cells.2.miR-324-5p was highly expressed in breast cancer serum,and its level had an AUC value of 0.7557 for the diagnosis of breast cancer,with a sensitivity of71% and a specificity of 74%.3.Disease-free survival and overall survival were longer in the low-level miR-324-5p expression group.Univariate and multivariate COX regression found that miR-324-5p was an independent prognostic factor for breast cancer.