CRISPR/Cas9 screenings unearth protein arginine methyltransferase 7 as a novel essential gene in prostate cancer metastasis

Cancer Lett. 2024 Apr 28:588:216776. doi: 10.1016/j.canlet.2024.216776. Epub 2024 Mar 2.

Abstract

Due to the limited effectiveness of current treatments, the survival rate of patients with metastatic castration-resistant prostate cancer (mCRPC) is significantly reduced. Consequently, it is imperative to identify novel therapeutic targets for managing these patients. Since the invasive ability of cells is crucial for establishing and maintaining metastasis, the aim of this study was to identify the essential regulators of invasive abilities of mCRPC cells by conducting two independent high-throughput CRISPR/Cas9 screenings. Furthermore, some of the top hits were validated using siRNA technology, with protein arginine methyltransferase 7 (PRMT7) emerging as the most promising candidate. We demonstrated that its inhibition or depletion via genetic or pharmacological approaches significantly reduces invasive, migratory and proliferative abilities of mCRPC cells in vitro. Moreover, we confirmed that PRMT7 ablation reduces cell dissemination in chicken chorioallantoic membrane and mouse xenograft assays. Molecularly, PRMT7 reprograms the expression of several adhesion molecules by methylating various transcription factors, such as FoxK1, resulting in the loss of adhesion from the primary tumor and increased motility of mCRPC cells. Furthermore, PRMT7 higher expression correlates with tumor aggressivity and poor overall survival in prostate cancer patients. Thus, this study demonstrates that PRMT7 is a potential therapeutic target and potential biomarker for mPCa.

Keywords: Adhesion; Invasion; Metastasis; PRMT7; Prostate cancer.

MeSH terms

  • Animals
  • CRISPR-Cas Systems
  • Early Detection of Cancer
  • Genes, Essential
  • Humans
  • Male
  • Mice
  • Prostatic Neoplasms, Castration-Resistant* / pathology
  • Protein-Arginine N-Methyltransferases* / genetics
  • Protein-Arginine N-Methyltransferases* / metabolism

Substances

  • Protein-Arginine N-Methyltransferases
  • PRMT7 protein, human
  • PRMT7 protein, mouse