ITGAM and neoplasm: To explore the underlying mechanism by which HMB boosts the anti‐tumor immunity of T cells, the immune checkpoint molecules on DCs (MHCII+CD11c+) and myeloid cells (MHCII+CD11b+) cells, within the tumor, tumor‐draining lymph nodes (dLNs), and mesenteric lymph nodes (MLNs) were examined at the early stage before the divergence of tumor size.