TP53 and breast carcinoma: Although functions and targets of PBSA within the tumour microenvironment, which includes cancer cells, immune cells, fibroblasts, secreted proteins, ECM components and blood vessels, remain to be further elucidated, our initial experiments show that PBSA inhibits proliferation of p53 wild‐type human breast cancer and p53‐deficient non–small‐cell lung cancer cells (data not shown).