Shakya Rajina, Suraneni Praveen, Zaslavsky Alexander, Rahi Amit, Magdongon Christine B, Gajjela Raju, Mattamana Basil B, Varma Dileep
Department of Cell and Developmental Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
Department of Urology, University of Michigan Medical School, Ann Harbor, MI 48108, USA.
bioRxiv. 2024 Oct 14:2024.10.14.618283. doi: 10.1101/2024.10.14.618283.
Castration-resistant prostate cancer (CRPC) progresses despite androgen deprivation therapy, as cancer cells adapt to grow without testosterone, becoming more aggressive and prone to metastasis. CRPC biology complicates the development of effective therapies, posing challenges for patient care. Recent gene-expression and metabolomics studies highlight the Hexosamine Biosynthetic Pathway (HBP) as a critical player, with key components like GNPNAT1 and UAP1 being downregulated in metastatic CRPC. GNPNAT1 knockdown has been shown to increase cell proliferation and metastasis in CRPC cell lines, though the mechanisms remain unclear. To investigate the cellular basis of these CRPC phenotypes, we generated a CRISPR-Cas9 knockout model of GNPNAT1 in 22Rv1 CRPC cells, analyzing its impact on metabolomic, glycoproteomic, and transcriptomic profiles of cells. We hypothesize that HBP inhibition disrupts the cytoskeleton, altering mitotic progression and promoting uncontrolled growth. GNPNAT1 KO cells showed reduced levels of cytoskeletal filaments, such as actin and microtubules, leading to cell structure disorganization and chromosomal mis-segregation. GNPNAT1 inhibition also activated PI3K/AKT signaling, promoting proliferation, and impaired cell adhesion by mislocalizing EphB6, enhancing migration via the RhoA pathway and promoting epithelial-to-mesenchymal transition. These findings suggest that HBP plays a critical role in regulating CRPC cell behavior, and targeting this pathway could provide a novel therapeutic approach.
去势抵抗性前列腺癌（CRPC）即便在雄激素剥夺治疗后仍会进展，因为癌细胞适应了在没有睾酮的情况下生长，变得更具侵袭性且易于转移。CRPC生物学特性使有效疗法的开发变得复杂，给患者护理带来了挑战。最近的基因表达和代谢组学研究突出了己糖胺生物合成途径（HBP）作为关键参与者，其关键成分如GNPNAT1和UAP1在转移性CRPC中表达下调。尽管机制尚不清楚，但在CRPC细胞系中，敲低GNPNAT1已被证明会增加细胞增殖和转移。为了研究这些CRPC表型的细胞基础，我们在22Rv1 CRPC细胞中构建了GNPNAT1的CRISPR - Cas9敲除模型，分析其对细胞代谢组学、糖蛋白组学和转录组学图谱的影响。我们假设HBP抑制会破坏细胞骨架，改变有丝分裂进程并促进失控生长。GNPNAT1敲除细胞显示细胞骨架细丝（如肌动蛋白和微管）水平降低，导致细胞结构紊乱和染色体错误分离。抑制GNPNAT1还激活了PI3K/AKT信号通路，促进增殖，并通过使EphB6定位错误损害细胞黏附，通过RhoA途径增强迁移并促进上皮 - 间质转化。这些发现表明HBP在调节CRPC细胞行为中起关键作用，靶向该途径可能提供一种新的治疗方法。
