The present invention provides diagnostic methods, therapeutic methods, and compositions for the treatment of cancer (e.g., a bladder cancer (e.g., UC, e.g., mUC), a kidney cancer, a lung cancer, a liver cancer, an ovarian cancer, a pancreatic cancer, a colorectal cancer, or a breast cancer). The invention is based, at least in part, on the discovery that expression levels of one or more biomarkers described herein in a sample from an individual having cancer can be used in methods of identifying an individual having a cancer who may benefit with an anti-cancer therapy that includes an immunotherapy (e.g., a PD-L1 axis binding antagonist such as an anti-PD-L1 antibody (e.g., atezolizumab)) and a suppressive stromal antagonist (e.g., a TGF-β antagonist), methods for selecting a therapy for an individual having cancer, methods of treating an individual having cancer, methods for assessing a response or monitoring the response of an individual to treatment with an anti-cancer therapy that includes an immunotherapy (e.g., a PD-L1 axis binding antagonist such as an anti-PD-L1 antibody (e.g., atezolizumab)) and a suppressive stromal antagonist (e.g., a TGF-β antagonist), and related kits, anti-cancer therapies, and uses.