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Purpose We investigated B-cell lymphoma 2 (BCL2) regulation across DNA, RNA, protein, and methylation status according to molecular subtype of breast cancer using The Cancer Genome Atlas (TCGA) database. Materials and Methods We analyzed clinical and biological data on 1,096 breast cancers from the TCGA database. Biological data included reverse phase protein array (RPPA), mRNA sequencing (mRNA-seq), mRNA microarray, methylation, copy number alteration linear, copy number alteration nonlinear, and mutation data. Results The luminal A and luminal B subtypes showed upregulated expression of RPPA and mRNAseq and hypomethylation compared to the human epidermal growth factor receptor 2 (HER2) and triple-negative subtypes (all p < 0.001). No mutations were found in any subjects. High mRNA-seq and high RPPA were strongly associated with positive estrogen receptor, positive progesterone receptor (all p < 0.001), and negative HER2 (p < 0.001 and p=0.002, respectively). Correlation analysis revealed a strong positive correlation between protein and mRNA levels and a strong negative correlation between methylation and protein and mRNA levels (all p < 0.001). The high BCL2 group showed superior overall survival compared to the low BCL2 group (p=0.006). Conclusion The regulation of BCL2 was mainly associated with methylation across the molecular subtypes of breast cancer, and luminal A and luminal B subtypes showed upregulated expression of BCL2 protein, mRNA, and hypomethylation. Although copy number alteration may have played a minor role, mutation status was not related to BCL2 regulation. Upregulation of BCL2 was associated with superior prognosis than downregulation of BCL2. [ABSTRACT FROM AUTHOR]

Purpose This study investigated the role of the education level (EL) as a prognostic factor for breast cancer and analyzed the relationship between the EL and various confounding factors. Materials and Methods The data for 64,129 primary breast cancer patients from the Korean Breast Cancer Registry were analyzed. The EL was classified into two groups according to the education period; the high EL group (⩾ 12 years) and low EL group (< 12 years). Survival analyses were performed with respect to the overall survival between the two groups. Results A high EL conferred a superior prognosis compared to a low EL in the subgroup aged > 50 years (hazard ratio, 0.626; 95% confidence interval [CI], 0.577 to 0.678) but not in the subgroup aged O 50 years (hazard ratio, 0.941; 95% CI, 0.865 to 1.024). The EL was a significant independent factor in the subgroup aged > 50 years according to multivariate analyses. The high EL group showed more favorable clinicopathologic features and a higher proportion of patients in this group received lumpectomy, radiation therapy, and endocrine therapy. In the high EL group, a higher proportion of patients received chemotherapy in the subgroups with unfavorable clinicopathologic features. The EL was a significant prognosticator across all molecular subtypes of breast cancer. [ABSTRACT FROM AUTHOR]