Kaushal Jyoti B, Raut Pratima, Halder Sushanta, Alsafwani Zahraa W, Parte Seema, Sharma Gunjan, Abdullah K M, Seshacharyulu Parthasarathy, Lele Subodh M, Batra Surinder K, Siddiqui Jawed A
Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA.
Department of Cell and Molecular Biology, University of Mississippi Medical Center, Jackson, MS, USA.
Oncogene. 2025 Apr;44(15):1007-1023. doi: 10.1038/s41388-024-03266-z. Epub 2025 Jan 16.
The functional activation of the androgen receptor (AR) and its interplay with the aberrant Hh/Gli cascade are pivotal in the progression of castration-resistant prostate cancer (CRPC) and resistance to AR-targeted therapies. Our study unveiled a novel role of the truncated form of Gli (t-Gli3) in advancing CRPC. Investigation into Gli3 regulation revealed a Smo-independent mechanism for its activation. Despite lacking a transactivation domain, t-Gli3 relies on androgen receptor variant 7 (AR-V7) for its action. Mechanistically, Gsk3β activation led to the t-Gli3 generation, and inhibition of Gsk3β supported the accumulation of full-length Gli3 expression through a non-canonical mechanism. Knockdown of Gsk3β (Gsk3β KD) reduces CRPC cell proliferation, induces apoptosis via mitochondrial fragmentation, and triggers metabolomic reprogramming. The in vivo studies with Gsk3β KD cells in the mouse prostate resulted in tumor growth retardation compared to scramble cells. RNA-seq HALLMARK Gene Set Enrichment Analysis (GSEA) analysis of Gsk3β KD revealed a positive enrichment of apoptosis, tumor suppressor gene, and negative enrichment of oncogenic pathway. Furthermore, combinational use of a Gsk3β inhibitor with anti-Smo or Gli1 significantly inhibited the CRPC cell growth, which is resistant to individual Smo or Gli1 inhibitor targeting. Intriguingly, solely targeting Gli3 showed effectiveness in inhibiting CRPC cell growth. Overall, our study underscores the clinical significance of Gli3, emphasizing t-Gli3, and provides novel insights into the interplay of the Gsk3β/t-Gli3/AR-V7 axis in CRPC.
雄激素受体（AR）的功能激活及其与异常的Hh/Gli信号级联的相互作用在去势抵抗性前列腺癌（CRPC）的进展以及对AR靶向治疗的耐药性中起着关键作用。我们的研究揭示了截短形式的Gli（t-Gli3）在推进CRPC进程中的新作用。对Gli3调控的研究揭示了一种不依赖Smo的激活机制。尽管缺乏反式激活结构域，但t-Gli3的作用依赖于雄激素受体变体7（AR-V7）。从机制上讲，Gsk3β的激活导致了t-Gli3的产生，而抑制Gsk3β通过一种非经典机制支持全长Gli3表达的积累。敲低Gsk3β（Gsk3β KD）可减少CRPC细胞增殖，通过线粒体碎片化诱导细胞凋亡，并引发代谢组重编程。与对照细胞相比，在小鼠前列腺中对Gsk3β KD细胞进行的体内研究导致肿瘤生长迟缓。对Gsk3β KD进行RNA测序的HALLMARK基因集富集分析（GSEA）显示，凋亡、肿瘤抑制基因呈正富集，致癌途径呈负富集。此外，将Gsk3β抑制剂与抗Smo或Gli1联合使用可显著抑制CRPC细胞生长，而单独使用Smo或Gli1抑制剂靶向对此耐药。有趣的是，仅靶向Gli3在抑制CRPC细胞生长方面显示出有效性。总体而言，我们的研究强调了Gli3的临床意义，突出了t-Gli3，并为CRPC中Gsk3β/t-Gli3/AR-V7轴的相互作用提供了新的见解。
