CTLA4 and breast cancer: Similarly, Kaewkangsadan et al. found a significant association between the presence of abundant levels of TILs, and CD4+, CD8+, CTLA-4+ stromal T cells, and pCR in 33 patients with locally advanced breast cancer undergoing NAC, suggesting that CTLA-4+ TILs may play a role in creating a good response to chemotherapy [34].