Karna Shibendra Kumar Lal, Lone Bilal Ahmad, Ahmad Faiz, Shahi Nerina, Pokharel Yuba Raj
Faculty of Life Science and Biotechnology, South Asian University, Akbar Bhawan, Chanakyapuri, New Delhi-110021, India.
EXCLI J. 2020 Sep 7;19:1211-1226. doi: 10.17179/excli2020-2363. eCollection 2020.
Breast cancer is the most common cancer among women worldwide. Among different types of breast cancer known, treatment of triple-negative breast cancer is a major challenge because of its aggressiveness and poor prognosis; thus, identification of specific drivers is required for targeted therapies of breast cancer malignancy. Protein Casein Kinase (CSNK) is a serine/threonine kinase that exists as a tetrameric complex consisting of two catalytic (α and /or α') and two regulatory β subunits. CSNK2β can also function independently without catalytic subunits and exist as a distinct population in cells. This study aims to elucidate the role of Casein Kinase 2β (CSNK2β) gene in cell proliferation, cell cycle, migration and apoptosis of triple-negative breast cancer MDA-MB-231 cells. The silencing of CSNK2β in MDA-MB-231 cells resulted in decreased cell viability and colony formation. Cell cycle analysis showed a significant arrest of cells in G2M phase. Hoechst and CM-H2DCFDA staining showed nuclear condensation and augmented intracellular reactive oxygen species (ROS) production. Furthermore, silencing of CSNK2β in MDA-MB-231 cells modulated the apoptotic machinery- BAX, Bcl-xL, and caspase 3; autophagy machinery-Beclin-1 and LC3-1; and inhibited the vital markers (p-ERK, c-Myc, NF-κB, E2F1, PCNA, p38-α) associated with cell proliferation and DNA replication pathways. In addition, knockdown of CSNK2β also affected the migration potential of MDA-MB-231, as observed in the wound healing and transwell migration assays. Altogether, the study suggests that CSNK2β silencing may offer future therapeutic target in triple-negative breast cancer.
乳腺癌是全球女性中最常见的癌症。在已知的不同类型乳腺癌中，三阴性乳腺癌的治疗是一项重大挑战，因为其具有侵袭性且预后较差；因此，需要识别特定驱动因素以进行乳腺癌恶性肿瘤的靶向治疗。蛋白酪蛋白激酶（CSNK）是一种丝氨酸/苏氨酸激酶，以由两个催化亚基（α和/或α'）和两个调节β亚基组成的四聚体复合物形式存在。CSNK2β也可在没有催化亚基的情况下独立发挥作用，并以细胞中的不同群体形式存在。本研究旨在阐明酪蛋白激酶2β（CSNK2β）基因在三阴性乳腺癌MDA-MB-231细胞的细胞增殖、细胞周期、迁移和凋亡中的作用。MDA-MB-231细胞中CSNK2β的沉默导致细胞活力和集落形成降低。细胞周期分析显示细胞在G2M期显著停滞。Hoechst和CM-H2DCFDA染色显示核浓缩和细胞内活性氧（ROS）生成增加。此外，MDA-MB-231细胞中CSNK2β的沉默调节了凋亡机制——BAX、Bcl-xL和caspase 3；自噬机制——Beclin-1和LC3-1；并抑制了与细胞增殖和DNA复制途径相关的关键标志物（p-ERK、c-Myc、NF-κB、E2F1、PCNA p38-α）。此外，如在伤口愈合和Transwell迁移试验中观察到的，CSNK2β的敲低也影响了MDA-MB-231的迁移潜力。总之，该研究表明CSNK2β沉默可能为三阴性乳腺癌提供未来的治疗靶点。
