الملخص
Objective To investigate the mechanisms of miRNA-15a and miRNA-16 in the process of reversing cisplatin resistance in ovarian cancer.Methods Human ovarian cancer cisplatin-resistant cell lines CoC1/DDP were transfected with miRNA-15a and miRNA-16 mimics and treated with cisplatin.qRT-PCR was used to detect the expression levels of miRNA-15a and miRNA-16 in normal CoC1/DDP cell group,cisplatin treated group,negative control group,miRNA-15a transfected group,miRNA-16 transfected group and overexpressed Bmi-1 plasmid.Western blot was used to detect the expression level of Bmi-1 in each group,CCK-8 and Annexin V/PI were used to detect cell survival and apoptosis,and γ-H2AX immunofluorescence was used to detect cell apoptosis.Results The CoC1/DDP ovarian cancer cell line shows low expression of miRNA-15a and miRNA-16,and high expression of Bmi-1 protein,which makes it resistant to cisplatin.When the levels of miRNA-15a and miRNA-16 are overexpressed,the Bmi-1 protein decreases(P<0.05),leading to a decrease in cell survival rate(P<0.05),a significant increase in DNA apoptosis(P<0.05),and more severe DNA damage(P<0.05).Overexpression of Bmi-1 plasmid can increase cell viability(P<0.05)and reduce the rate of cell apoptosis(P<0.05).Conclusion The Bmi-1 protein may be a target for the regulation of miRNA-15a and miRNA-16,and overexpression of miRNA-15a and miRNA-16 can increase the sensitivity of ovarian cancer cells to cisplatin by reducing the Bmi-1 protein.This provides a new idea for predicting molecular markers of cisplatin resistance in ovarian cancer and overcoming drug resistance targets in ovarian cancer.
الملخص
OBJECTIVE@#To develop and validate a user-friendly risk score for older mitral regurgitation (MR) patients, referred to as the Elder-MR score.@*METHODS@#The China Senile Valvular Heart Disease (China-DVD) Cohort Study functioned as the development cohort, while the China Valvular Heart Disease (China-VHD) Study was employed for external validation. We included patients aged 60 years and above receiving medical treatment for moderate or severe MR (2274 patients in the development cohort and 1929 patients in the validation cohort). Candidate predictors were chosen using Cox's proportional hazards model and stepwise selection with Akaike's information criterion.@*RESULTS@#Eight predictors were identified: age ≥ 75 years, body mass index < 20 kg/m2, NYHA class III/IV, secondary MR, anemia, estimated glomerular filtration rate < 60 mL/min per 1.73 m2, albumin < 35 g/L, and left ventricular ejection fraction < 60%. The model displayed satisfactory performance in predicting one-year mortality in both the development cohort (C-statistic = 0.73, 95% CI: 0.69-0.77, Brier score = 0.06) and the validation cohort (C-statistic = 0.73, 95% CI: 0.68-0.78, Brier score = 0.06). The Elder-MR score ranges from 0 to 15 points. At a one-year follow-up, each point increase in the Elder-MR score represents a 1.27-fold risk of death (HR = 1.27, 95% CI: 1.21-1.34, P < 0.001) in the development cohort and a 1.24-fold risk of death (HR = 1.24, 95% CI: 1.17-1.30, P < 0.001) in the validation cohort. Compared to EuroSCORE II, the Elder-MR score demonstrated superior predictive accuracy for one-year mortality in the validation cohort (C-statistic = 0.71 vs. 0.70, net reclassification improvement = 0.320, P < 0.01; integrated discrimination improvement = 0.029, P < 0.01).@*CONCLUSIONS@#The Elder-MR score may serve as an effective risk stratification tool to assist clinical decision-making in older MR patients.