Clinical management of radioiodine-refractory differentiated thyroid cancer (RR-DTC) is extremely difficult. Re-differentiation compounds

such as retinoids

peroxisome proliferator-activated receptor (PPAR) agonists

DNA methyltransferase inhibitors and histone deacetylase inhibitors

have been used in trials to increase iodine uptake in RR-DTC. However

data on these drugs failed to meet the initial high expectations. In recent years

targeted agents have been increasingly used in pre-clinical and clinical studies to induce re-differentiation and mediate

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I therapy

and the outcomes are encouraging.