METHODS: Publicly available breast cancer datasets analyses and Kaplan-Meier survival analyses were performed to reveal the expression and clinical relevance of atypical CDKs in breast cancer. CDK16 protein expression was further examined by immunohistochemical and immunoblot analyses of clinical samples. Cell proliferation was measured by colony formation and MTT analyses. Cell cycle and apoptosis were examined by fluorescence-activated cell sorting (FACS) analysis. Wound-healing and trans-well invasion assays were conducted to test cell migration ability. The functions of CDK16 on tumorigenesis and metastasis were evaluated by cell line-derived xenograft, patient-derived organoid/xenograft, lung metastasis and systemic metastasis mouse models. Transcriptomic analysis was performed to reveal the potential molecular mechanisms involved in the function of CDK16. Pharmacological inhibition of CDK16 was achieved by the small molecular inhibitor rebastinib to further assess the anti-tumor utility of targeting CDK16.
RESULTS: CDK16 is highly expressed in breast cancer, particularly in triple-negative breast cancer (TNBC). The elevated CDK16 expression is correlated with poor outcomes in breast cancer patients. CDK16 can improve the proliferation and migration ability of TNBC cells in vitro, and promote tumor growth and metastasis of TNBC in vivo. Both genetic knockdown and pharmacological inhibition of CDK16 significantly suppress the tumor progression of TNBC. Mechanistically, CDK16 exerts its function by phosphorylating protein regulator of cytokinesis 1 (PRC1) to regulate spindle formation during mitosis.
CONCLUSIONS: CDK16 plays a critical role in TNBC and is a novel promising therapeutic target for TNBC.
方法:进行了公开可用的乳腺癌数据集分析和Kaplan-Meier生存分析,以揭示乳腺癌中非典型CDK的表达和临床相关性。通过临床样品的免疫组织化学和免疫印迹分析进一步检查CDK16蛋白表达。通过集落形成和MTT分析测量细胞增殖。通过荧光激活细胞分选(FACS)分析检查细胞周期和凋亡。进行伤口愈合和跨孔侵袭测定以测试细胞迁移能力。通过细胞系来源的异种移植评估CDK16在肿瘤发生和转移中的功能。患者来源的类器官/异种移植物,肺转移和全身转移小鼠模型。进行转录组学分析以揭示参与CDK16功能的潜在分子机制。通过小分子抑制剂雷巴替尼实现CDK16的药理学抑制,以进一步评估靶向CDK16的抗肿瘤效用。
结果:CDK16在乳腺癌中高表达,特别是三阴性乳腺癌(TNBC)。CDK16表达升高与乳腺癌患者的不良预后相关。CDK16在体外可提高TNBC细胞的增殖和迁移能力,并促进TNBC在体内的生长和转移。CDK16的基因敲除和药理学抑制均显著抑制TNBC的肿瘤进展。机械上,CDK16通过磷酸化胞质分裂1(PRC1)的蛋白质调节剂来调节有丝分裂过程中的纺锤体形成,从而发挥其功能。
结论:CDK16在TNBC中起关键作用,是TNBC新的有希望的治疗靶点。