Guizhou University of Traditional Chinese Medicine, Guiyang, China.
State Key Laboratory for Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang, 550014, Guizhou, People's Republic of China.
Breast Cancer Res Treat. 2024 Sep;207(2):405-415. doi: 10.1007/s10549-024-07372-0. Epub 2024 Jun 14.
Breast cancer is the most frequent cancer in women with significant death rate. Morbidity is associated with drug resistance and metastasis. Development of novel drugs is unmet need. The aim of this study is to show potent anti-neoplastic activity of the UM171 compound on breast cancer cells and its mechanism of action.
The inhibitory effect of UM171 on several breast cancer (BC) cell lines was examined using MTT and colony-forming assays. Cell cycle and apoptosis assays were utilized to determine the effect of UM171 on BC cell proliferation and survival. Wound healing scratch and transwell migration assays were used to examine the migration of BC cell lines in culture. Xenograft of mouse model with 4T1 cells was used to determine inhibitory effect of UM171 in vivo. Q-RT-PCR and western blotting were used to determine the expression level of genes effected by UM171. Lentivirus-mediated shRNAs were used to knockdown the expression of KLF2 in BC cells.
UM171 was previously identified as a potent agonist of human hematopoietic stem cell renewal and inhibitor of leukemia. In this study, UM171 was shown to inhibit the growth of multiple breast cancer cell lines in culture. UM171-mediated growth inhibition was associated with the induction of apoptosis, G2/M cell cycle arrest, lower colony-forming capacity, and reduced motility. In a xenotransplantation model of mouse triple-negative breast cancer 4T1 cells injected into syngeneic BALB/c mice, UM171 strongly inhibited tumor growth at a level comparable to control paclitaxel. UM171 increased the expression of the three PIM genes (PIM1-3) in breast cancer cells. Moreover, UM171 strongly induced the expression of the tumor suppressor gene KLF2 and cell cycle inhibitor P21. Accordingly, knockdown of KLF2 using lentivirus-mediated shRNA significantly attenuated the growth suppressor activity of UM171. As PIM1-3 act as oncogenes and are involved in breast cancer progression, induction of these kinases likely impedes the inhibitory effect of KLF2 induction by UM171. Accordingly, combination of UM171 with a PAN-PIM inhibitor LGH447 significantly reduced tumor growth in culture.
These results suggested that UM171 inhibited breast cancer progression in part through activation of KLF2 and P21. Combination of UM171 with a PAN-PIM inhibitor offer a novel therapy for aggressive forms of breast cancer.
乳腺癌是女性中最常见的癌症，死亡率较高。发病率与药物耐药性和转移有关。因此，开发新的药物是一个未满足的需求。本研究旨在展示 UM171 化合物在乳腺癌细胞中的强大抗肿瘤活性及其作用机制。
使用 MTT 和集落形成实验检测 UM171 对几种乳腺癌（BC）细胞系的抑制作用。细胞周期和凋亡实验用于确定 UM171 对 BC 细胞增殖和存活的影响。划痕愈合和 Transwell 迁移实验用于检测 BC 细胞系在培养中的迁移。使用携带 4T1 细胞的小鼠异种移植模型来确定 UM171 的体内抑制作用。Q-RT-PCR 和 Western blot 用于确定 UM171 影响的基因表达水平。慢病毒介导的 shRNA 用于敲低 BC 细胞中 KLF2 的表达。
UM171 先前被鉴定为人类造血干细胞更新的有效激动剂和白血病抑制剂。在这项研究中，UM171 被证明可以抑制多种乳腺癌细胞系在培养中的生长。UM171 介导的生长抑制与诱导凋亡、G2/M 细胞周期阻滞、降低集落形成能力和降低迁移能力有关。在注射同源 BALB/c 小鼠中的三阴性乳腺癌 4T1 细胞的异种移植模型中，UM171 强烈抑制肿瘤生长，其水平可与对照紫杉醇相媲美。UM171 增加了乳腺癌细胞中三个 PIM 基因（PIM1-3）的表达。此外，UM171 强烈诱导肿瘤抑制基因 KLF2 和细胞周期抑制剂 P21 的表达。因此，使用慢病毒介导的 shRNA 敲低 KLF2 显著减弱了 UM171 的生长抑制活性。由于 PIM1-3 作为癌基因参与乳腺癌的进展，因此诱导这些激酶可能会阻碍 UM171 诱导 KLF2 诱导的抑制作用。因此，UM171 与泛-PIM 抑制剂 LGH447 的组合在培养中显著降低了肿瘤生长。
这些结果表明，UM171 通过激活 KLF2 和 P21 抑制乳腺癌进展。UM171 与泛-PIM 抑制剂的组合为侵袭性乳腺癌提供了一种新的治疗方法。
