Project description:Platinum-based drugs (Pt drugs) are widely used in cancer chemotherapy, yet their genome-wide DNA binding patterns remain incompletely understood. Here, we present Pt-seq, an antibody-assisted, genome-wide method for mapping Pt-DNA adducts at single-base resolution. By employing exo- and endo- nucleases to remove background DNA, Pt-seq enables highly robust and sensitive profiling of binding sites for cisplatin, oxaliplatin, lobaplatin, and a Pt(IV) complex. Using Pt-seq, we identified hundreds to a few thousand binding clusters that are 10-20 kb in length and highly consistent among different Pt drugs. Notably, these binding clusters predominantly localize to centromeric and rDNA regions. In cisplatin-resistant cells, we found significantly reduced binding within these regions, suggesting a potential role in drug resistance. Moreover, we found that de novo mutations in cancer cells can create novel binding sites for Pt drugs. Based on this, we demonstrated that ICR-191, an acridine orange compound capable of inducing G insertions, enhances cisplatin-DNA crosslinking and sensitizes cells to Pt drugs. Collectively, Pt-seq sensitively profiles Pt drug-DNA interactions and deepens our understanding of the genome-wide effect of chemotherapeutic drugs.
