HDAC9 and Burkitt lymphoma: It is also worth mentioning that we used first-generation (17-DMAG) and second-generation (ganetespib) HSP90 inhibitors as a combination strategy with CIK cells, and the future availability of dual inhibitors (such as HSP90-HDAC [59]) may further contribute to defining the cytotoxic efficacy of CIK cells in BL.