Modified Protein Function
Other targeted therapies modify the function of proteins that regulate gene expression and other cellular functions.
- Vorinostat (Zolinza®) is approved for the treatment of cutaneous T-cell lymphoma (CTCL) that has persisteded, progressed, or recurred during or after treatment with other medicines. This small-molecule drug inhibits the activity of a group of enzymes called histone deacetylases (HDACs), which remove small chemical groups called acetyl groups from many different proteins, including proteins that regulate gene expression. By altering the acetylation of these proteins, HDAC inhibitors can induce tumor cell differentiation, cell cycle arrest, and apoptosis.
- Romidepsin (Istodax®) is approved for the treatment of CTCL in patients who have received at least one prior systemic therapy. This small-molecule drug inhibits members of one class of HDACs and induces tumor cell apoptosis.
- Bexarotene (Targretin®) is approved for the treatment of some patients with CTCL. This drug belongs to a class of compounds called retinoids, which are chemically related to vitamin A. Bexarotene binds selectively to, and thereby activates, retinoid X receptors. Once activated, these nuclear proteins act in concert with retinoic acid receptors to regulate the expression of genes that control cell growth, differentiation, survival, and death.
- Alitretinoin (Panretin®) is approved for the treatment of cutaneous lesions in patients with AIDS-related Kaposi sarcoma. This retinoid binds to both retinoic acid receptors and retinoid X receptors.
- Tretinoin (Vesanoid®) is approved for the induction of remission in certain patients with acute promyelocytic leukemia. This retinoid binds to and thereby activates retinoic acid receptors.