A review published in Genes & Diseases highlights the complex interplay between protein arginine methylation and ubiquitination, two forms of protein modification that can profoundly influence cancer development, progression and treatment response. The article brings together current understanding of how these interconnected molecular processes regulate proteins involved in cancer and identifies opportunities for future therapeutic approaches.
Protein arginine methyltransferases (PRMTs) modify arginine residues in histone and nonhistone proteins, influencing protein activity, interactions and cellular functions. Ubiquitination, meanwhile, can control the stability and activity of proteins by attaching ubiquitin molecules to selected targets. Rather than operating independently, these systems form a dynamic, bidirectional network in which methylation can alter ubiquitination and protein degradation, while ubiquitination can regulate the stability and activity of PRMT enzymes.
This methylation–ubiquitination crosstalk is connected with numerous processes central to cancer, including tumor invasion and metastasis, cell proliferation, apoptosis, ferroptosis, DNA repair and genomic stability, metabolic reprogramming, drug resistance and immune escape. By changing whether important proteins are stabilized or degraded, the network can influence signaling pathways that determine how cancer cells grow, survive, spread and respond to treatment.
PRMT enzymes can, for example, modify target proteins in ways that reduce their recognition by ubiquitin ligases, helping those proteins avoid degradation. In other circumstances, methylation can encourage ubiquitination and accelerate protein removal. The relationship also works in reverse: E3 ubiquitin ligases and deubiquitinases can alter the stability of PRMTs themselves, creating an intricate system of molecular feedback.
These mechanisms may have important implications for cancer therapy. Targeting enzymes involved in both pathways could offer new ways to address treatment resistance and influence immune responses. Potential future directions include dual-function inhibitors, small-molecule degraders and engineered nanobodies, alongside strategies combining modulation of these pathways with immune checkpoint blockade. However, challenges remain, including the highly context-dependent nature of the molecular network and the need for greater precision when targeting it therapeutically.
