I was planning to evaluate the protein expression profile of a gene of my interest, in breast cancer patients. Does anyone know if such dataset ( like we use TCGA datasets to examine mRNA expression )exists?
Related data can be mined with the TCGA database to form mutual validation. I know of a database named CPTAC that can get results. This is the website: https://cptac-data-portal.georgetown.edu/datasets
You can check gene expression at protein level using Human Protein Atlas (https://www.proteinatlas.org). Also, NCI Proteomic Data Commons can be explored (https://pdc.cancer.gov/pdc/)