Background. Identification of new biomarkers can facilitate the development of effective therapeutic strategies in breast cancer (BC). Data from previous studies have revealed that differentiated embryonic chondrocyte gene (DEC) 1 and DEC2 might involve in the progression of various cancer types. We explored the expression profiles and function of DEC1/2 in BC patients in this study. Methods. The mRNA expression of DEC1/2 in BC patients and cell lines were taken from the Oncomine and Cancer Cell Line Encyclopedia database. The prognostic impacts of DEC1/2 were mined from the bc-GenExMiner and Kaplan–Meier plotter database. The impact of DEC1/2 genomic alterations on patient survival was calculated by cBioPortal. DEC2 protein expressions were confirmed by Western blotting (WB) in 10 pairs of BC samples. In addition, DEC2 sgRNA was constructed to confirm its affection on cell viability, invasion, and colony formation. Results. The DEC1 and DEC2 mRNA levels are both lower in BC tissues than normal tissues. DEC1/2 expression was high in progesterone receptor (PR) positive BC patients (), but low in human epidermal growth factor receptor 2 (HER2) positive patients (). Lower DEC2 mRNA level has significant association with more aggressive pathogenic grade () and worse overall survival (OS) of BC patients (). Subgroup analysis showed that low DEC2 level was correlated with worse OS in estrogen receptor (ER) positive BC (). DEC2 () alteration was significantly correlated with worse OS in BC patients. WB results also confirmed the lower DEC2 protein levels in BC samples than their paired normal tissues. And, DEC2 silencing by sgRNA resulted in a significant increasing in cell viability, invasion, and colony formation. Conclusion. DEC2 might serve as a tumor suppressor, and its disfunction may involve in the tumorigenesis and indicate bad clinical outcomes in BC patients.

中文翻译：

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DEC2 可作为乳腺癌的潜在肿瘤抑制因子

背景。新的生物标志物的鉴定可以促进乳腺癌（BC）有效治疗策略的发展。先前研究的数据表明，分化的胚胎软骨细胞基因（DEC）1和DEC2可能参与各种癌症类型的进展。我们在本研究中探讨了 BC 患者中 DEC1/2 的表达谱和功能。方法. BC 患者和细胞系中 DEC1/2 的 mRNA 表达取自 Oncomine and Cancer Cell Line Encyclopedia 数据库。DEC1/2 的预后影响来自 bc-GenExMiner 和 Kaplan-Meier 绘图仪数据库。通过 cBioPortal 计算 DEC1/2 基因组改变对患者生存的影响。通过蛋白质印迹 (WB) 在 10 对 BC 样品中确认 DEC2 蛋白表达。此外，构建 DEC2 sgRNA 以确认其对细胞活力、侵袭和集落形成的影响。结果。BC 组织中的 DEC1 和 DEC2 mRNA 水平均低于正常组织。DEC1/2 在孕激素受体 (PR) 阳性 BC 患者中高表达（)，但在人表皮生长因子受体 2 (HER2) 阳性患者中较低 (）。较低的 DEC2 mRNA 水平与更具侵袭性的致病等级显着相关。)和更差的 BC 患者总生存期 (OS) (）。亚组分析表明，低 DEC2 水平与雌激素受体（ER）阳性 BC 中较差的 OS 相关（）。十二月2 ()改变与 BC 患者较差的 OS 显着相关。WB 结果还证实了 BC 样本中的 DEC2 蛋白水平低于其配对的正常组织。并且，sgRNA 对 DEC2 的沉默导致细胞活力、侵袭和集落形成显着增加。结论。DEC2 可能作为肿瘤抑制因子，其功能障碍可能涉及肿瘤发生并表明 BC 患者的不良临床结果。