Integrated global proteomic and phosphoproteomic analysis of cisplatin-induced apoptosis in A549 cells

Abstract

Protein phosphorylation, a widely occurring and significant post-translational modification, is integral to various biological processes. We previously utilized a protein affinity probe to identify genes damaged by cisplatin, revealing that it inflicts substantial damage on protein kinase and protein phosphatase genes. In this study, we investigated cisplatin-induced alterations in the global proteome and phosphoproteome of A549 cells. Employing Fe-IMAC beads and tyrosine phosphorylation enrichment antibodies, we identified 6944 protein groups and 18,274 phosphorylation sites on 4915 proteins across three biological replicates of both cisplatin-treated A549 cells and control cells. Among these, 730 tyrosine phosphorylation sites were identified—marking the most substantial discovery of such sites in A549 cells following cisplatin treatment. Bioinformatics analysis indicated that the proteins exhibiting significant phosphorylation level changes predominantly involved in RNA processing, modification, transcription, translation, and the spliceosome. This suggests that cisplatin-induced damage to protein kinases and phosphatases may disrupt the normal function of these proteins, consequently impairing DNA replication, RNA translation, and shearing, ultimately culminating in tumor cell death. Moreover, we cross-referenced our proteomic data with our previously obtained cisplatin-damaged genes, observing that the majority of down-regulated proteins derived from cisplatin-induced gene damage. The data are available on ProteomeXchange under the identifier PXD053902.