Table 1.
Summary of the effects of HDAC inhibitors on MDSCs in several cancers.
| HDAC Inhibitors | Class | Cancer type | Mechanism of action on MDSCs | References |
|---|---|---|---|---|
| Trichostatin A (TSA) | I, II | In vitro | Accumulation of CD11b+Gr1+ myeloid cell via iNOS1 and HO-1upregulation | (84) |
| Valproic acid | I | In vitro | Induced macrophage and DC generation | (85) |
| Lymphoma | Reduced PMN-MDSCs accumulation in-vitro and decrease tumor growth in-vivo
Repressed PD-L1, TLR4, Rb1, IL-4Rα/ARG1 signaling axis in MDSCs |
(86) | ||
| Decreased tumor-infiltrating MDSCs via repression of CCR2 | (76) | |||
| Melanoma | Induced M-MDSCs accumulation Downregulated MDSCs ARG1, IL-6 and IL-10 via IRF1/IRF8 activation |
(60) | ||
| Entinostat | I | Lung Renal |
Blocked MDSCs immunosuppressive function through reduced expression of ARG1, iNOS, and COX2 | (87) |
| Breast Pancreatic |
Induced less suppressive PMN-MDSCs that promoted T cell proliferation | (88) | ||
| Breast | Downregulation of CD40 expression in PMN-MDSCs and M-MDSCs | (89) | ||
| Lung Breast Oesophageal |
Reduced trafficking of PMN-MDSCs and MDSCs from bone marrow to pre-metastatic microenvironment via downregulating CXCR2 and CCR2. | (90) | ||
| Lymphoma Lung |
Reduced PMN-MDSCs immunosuppressive function | (59) | ||
| Ricolinostat | II | Reduced M-MDSCs accumulation | ||
| Mocetinostat | I, IV | Colorectal | Reduced intratumoral MDSCs accumulation Induced expression of genes involved in immune evasion and antigen presentation |
(91) |
| Sodium butyrate Vorinostat |
I, II | In-vitro | Promoted MDSCs apoptosis via increased production of ROS in vitro | (92) |
| Breast | Decreased MDSCs accumulation in blood, spleen, and tumor while activating CD8+T | |||
| Vorinostat | Melanoma | Reduced MDSCs recruitment into the tumor site via downregulation of CCL2 | (93) | |
| Neuroblastoma | Decreased M-MDSCs accumulation Reduced transcript for ARG1, S100A8, S100A9 and PD-L1 |
(94) | ||
| ACY241 | IIb | Myeloma | Reduced MDSCs proportion | (95) |
| CG-745 | I, IIb | Renal cell carcinoma Hepatocellular Carcinoma Colorectal |
reduced Treg production via increased expression of IL-2 and IFN-γ Induced immune microenvironmental changes via Inhibiting tumor-infiltrating MDSCs |
(96) (97) |