Decitabine, sold under the brand name Dacogen among others, acts as a nucleic acid synthesis inhibitor. It is a

medication A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy ( pharmacotherapy) is an important part of the medical field and ...

for the treatment of

myelodysplastic syndromes A myelodysplastic syndrome (MDS) is one of a group of cancers in which immature blood cells in the bone marrow do not mature, and as a result, do not develop into healthy blood cells. Early on, no symptoms typically are seen. Later, symptoms may ...

, a class of conditions where certain blood cells are dysfunctional, and for

acute myeloid leukemia Acute myeloid leukemia (AML) is a cancer of the myeloid line of blood cells, characterized by the rapid growth of abnormal cells that build up in the bone marrow and blood and interfere with normal blood cell production. Symptoms may inclu ...

(AML). Chemically, it is a

cytidine Cytidine (symbol C or Cyd) is a nucleoside molecule that is formed when cytosine is attached to a ribose ring (also known as a ribofuranose) via a β-N1- glycosidic bond. Cytidine is a component of RNA. It is a white water-soluble solid. which ...

analog Analog or analogue may refer to: Computing and electronics * Analog signal, in which information is encoded in a continuous variable ** Analog device, an apparatus that operates on analog signals *** Analog electronics, circuits which use analog ...

Medical uses

Decitabine is used to treat

(MDS) including previously treated and untreated, de novo and secondary MDS of all French-American-British subtypes ( refractory anemia, refractory anemia with ringed sideroblasts, refractory anemia with excess blasts, refractory anemia with excess blasts in transformation, and

chronic myelomonocytic leukemia Chronic myelomonocytic leukemia (CMML) is a type of leukemia, which are cancers of the blood-forming cells of the bone marrow. In adults, blood cells are formed in the bone marrow, by a process that is known as haematopoiesis. In CMML, there are ...

) and Intermediate-1, Intermediate-2, and High-Risk International Prognostic Scoring System groups. In patients with chronic kidney disease, Batty and colleagues reported the first case series on the feasibility of therapy with hypomethylating agents in patients with chronic kidney disease. It also has EU approval for

(AML).

Pharmacology

Decitabine is a hypomethylating agent. It hypomethylates DNA by inhibiting

DNA methyltransferase In biochemistry, the DNA methyltransferase (DNA MTase, DNMT) family of enzymes catalyze the transfer of a methyl group to DNA. DNA methylation serves a wide variety of biological functions. All the known DNA methyltransferases use S-adenosyl m ...

. It functions in a similar manner to

azacitidine Azacitidine, sold under the brand name Vidaza among others, is used for the treatment of myelodysplastic syndrome, myeloid leukemia, and juvenile myelomonocytic leukemia. It is a chemical analog of cytidine, a nucleoside in DNA and RNA. Azacit ...

, although decitabine can only be incorporated into DNA strands while azacitidine can be incorporated into both DNA and RNA chains. It incorporates into DNA strands upon replication, and then when DNA methyltransferases (DNMTs) such as DNMT1, are engaged to bind the DNA and to replicate the methylation to the daughter strand, DNMTs are bound to decitabine irreversibly and cannot disengage. Therefore, the action of decitabine is division-dependent, meaning the cells have to divide in order for the pharmaceutical to act. Therefore, cancer cells which divide much more rapidly than most other cells in the body will be more severely affected by decitabine just because they replicate more. In cancer cells, and more specifically in haematological malignancies, it seems that DNA hypermethylation is really critical for their development. Methylation of CpG islands upstream of tumor suppressor genes in order to silence them seems to be critical for these type of cancers. Thus at optimal doses, decitabine blocks this type of methylation and has an anti-neoplastic effect.

Research

Atherosclerosis

A number of investigators have shown a relationship between atherosclerosis and disturbed blood flow. This upregulates DNA methyltransferase expression, which leads to genome-wide DNA methylation alterations and global gene expression changes. These studies have revealed several mechanosensitive genes, such as HoxA5, Klf3, and Klf4, whose promoters were hypermethylated by disturbed blood flow, but rescued by DNA methyltransferases inhibitors such as 5-aza-2'-deoxycytidine. It has been found that use of this DNA methyltranferase inhibitor prevents atherosclerosis lesion formation and reduces the production of inflammatory cytokines by macrophages.

References

External links