Amifostine |
Small-molecule (thiol) |
Salivary glands mucosa |
Free radical scavenger and other (see text) |
Tetracycline |
Small-molecule (antibiotic) |
Bone marrow (HPC protector) |
Unknown mechanism not related to its anti-microbial properties |
Genistein |
Small-molecule (soy isoflavone) |
Bone marrow (HPC protector) |
Multiple mechanisms (e.g., anti-inflammatory, antioxidant, free radical scanger, stimulator of DNA synthesis) |
Captopril (also perindopril) |
Small-molecule (anti-hypertensive drug) |
Kidney protector, lung, bone marrow (HPC protector) |
Angiotensin onverting enzyme (ACE) inhibitor, reduced inflammation; mechanism unclear |
3,3′-Diindolylmethane (DIM) |
Small-molecule (indole derivative) |
GI system bone marrow |
Simulates ATM signaling and DNA damage response protection against oxidative stress |
Rapamycin |
Small-molecule (MTOR inhibitor) |
Head and neck mucosa |
MTOR inhibitor; blocks radiation-induced cellular senescence |
ON01210/Ex-Rad |
Small-molecule (chlorobenzyl sulfone derivative) |
Bone marrow GI system |
Tyrosine kinase inhibitor; attenuation of ATM/p53 signaling; up-regulation of PI3 kinase signaling |
γ-Tocotrienol (GT3) |
Small-molecule (vitamin E isomer) |
Bone marrow (HPC protector) GI system |
Antioxidant |
δ-Tocotrienol |
Small-molecule (vitamin E isomer) |
Bone marrow |
Antioxidant |
Palliformin |
Protein (keratinocyte growth factor) |
Oral and esophageal mucosa |
Stimulates epithelial cell proliferation; inhibits apoptosis |
Superoxide dismutase (MnSOD) |
Protein (enzyme, delivered by gene therapy approach) |
Lung, esophagus, oral mucosa |
Metabolizes ROS |
CBLB502 (entolimod) |
Protein (flagellin derivative) |
GI system, bone marrow, skin, oral mucosa |
TLR5 agonist; stimulates NF-κB signaling, induction of protective cytokines |
TGF-β3 |
Protein (transforming growth factor-β3) |
Lung |
Attenuates radiation-induced pulmonary function |
R-spondin1 (Rspo1) |
Protein (intestinal cell mitogen) |
GI system |
Accelerates regeneration of irradiated intestine through the Wnt/β-catenin pathway |
Mesenchymal stem cell (MSC) transplant |
Cellular therapy |
Bone marrow various other tissues |
Engraft and differentiation of MSCs; cytokine production; suppression of immune response and inflammation |
Myeloid progenitor cells (MPCs) |
Cellular therapy |
Bone marrow GI system |
HPC reconstitution; preserves structural integrity of the gut |
Tocopherol succinate (TS)-mobilized progenitor cells |
Cellular therapy |
Bone marrow GI system |
HPC reconstitution, bridging therapy; protection of the GI system |
Bone marrow stromal cells |
Cellular therapy |
GI system |
Increases blood levels of intestinal growth factors; induces regeneration of intestinal stem cells |