Research in precision oncology is utilizing proteomics and multi-omics integration to better understand tumor heterogeneity and discover biomarkers. This involves various techniques, including mass spectrometry-based proteomics and liquid biopsy technologies, as well as the application of artificial intelligence and bioinformatics tools. The field is exploring the use of these approaches to identify biomarkers for various types of cancer, including lung and colorectal cancer, and to inform precision drug discovery and immunotherapy.