NRK (Nik related kinase) is a serine/threonine protein kinase located on chromosome X that plays important roles in cellular proliferation, migration, and fibrosis. NRK is upregulated in benign prostatic hyperplasia (BPH), where it localizes predominantly to stromal tissue and correlates with disease severity 1. Silencing NRK inhibits stromal cell proliferation, migration, fibrosis, and epithelial-mesenchymal transition (EMT), while promoting apoptosis and cell cycle arrest 1. NRK expression positively correlates with fibrotic markers including α-SMA, collagen-I, and N-cadherin, suggesting a role in fibrogenic signaling 1. Evolutionarily, NRK underwent accelerated evolution in placental mammals with acquisition of a novel exon in their ancestral lineage, indicating functional adaptation for placental development and fetoplacental labor induction 2. The structural changes from this new exon-encoded loop, surrounded by accelerated protein regions, likely modulate NRK enzymatic activity 2. Although UniProt annotations suggest NRK may phosphorylate cofilin-1 to induce actin polymerization and participate in TNF-induced signaling, these functions require further experimental validation in the provided literature. NRK represents a promising therapeutic target for proliferative and fibrotic diseases including BPH and potentially renal fibrosis.