PRMT1 was identified as a regulator of arginine methylation in ovarian cancer cells treated with cisplatin. It was revealed that DNA dependent protein kinase (DNA-PK) binds to and phosphorylates PRMT1 in response to cisplatin, inducing its chromatin recruitment and redirecting its enzymatic activity toward R3 of histone H4 (H4R3). On chromatin, the DNA-PK/PRMT1 axis induced senescence-associated secretory phenotype (SASP) through H4R3me2a deposition which protected from apoptosis cells confronted with sustained DNA damage. PRMT1 inhibition resensitised cells to cisplatin. This evidence concerns the gene PRKDC and ovarian cancer.