Nair and coworkers compared the RNA-sequencing data between CRC tissue-derived and normal tissue-derived immature myeloid-derived suppressor cells (I-MDSCs), a class of immune suppressive cells crucial to tumor metastasis, and found that 148 of the upregulated genes in tumor-infiltrating I-MDSCs were involved in HDAC activation and that HDAC inhibitors significantly reduced MDSC function and the expression of recruitment-associated genes ARG1, CCR2, and ITGAL[45]. Here, HDAC9 is linked to neoplasm.