CTLA4 and breast adenocarcinoma: EMT6 is partially responsive to anti-CTLA-4 and anti-PD-L1 therapies, making it suitable for investigating immune checkpoint inhibitor responsiveness and interactions with the tumor microenvironment E0771, derived from C57BL/6 mouse mammary adenocarcinoma, exhibits moderate-to-high metastatic potential, primarily targeting the lungs [144, 152].