Fatty acid to enhance anticancer drug

May 7, 2010

Scientists of the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ) have discovered that bioavailability and efficacy of the blood cancer drug azacytidine increase when the substance is coupled to a fatty acid.

Chemical changes in the genetic material, known as epigenetic modifications, regulate the activity of many genes. Thus, attachment of methyl groups to DNA often inactivates important cellular growth brakes. Therefore, this process called methylation is believed to be a major cause of uncontrolled division of cancer cells. Specific enzymes, the DNA methyltransferases, are responsible for methylation.

Unlike changes in the blueprint of the genetic material, epigenetic mutations are reversible and, thus, cancer cells can be restored to their "normal state". Substances causing this re-programming are already being used as . Examples are azacytidine and decitabine, which are used in the treatment of a specific type of blood cancer called . Both substances are incorporated into the cell's genetic material, where they act as a trap for methyltransferases. They form permanent chemical bonds with the enzyme, thereby catching the methyltransferases one by one, so that no more genes are being silenced.

Scientists in Professor Frank Lyko's team at DKFZ were searching for azacytidine variants with enhanced efficacy, because the drug still remains ineffective in many cases even when it is has been established that tumor brakes have been put out of effect by methylation. Researchers believe that this therapy resistance is frequently caused by the fact that not enough of the agent gets into the interior of the cells, because cancer cells lack particular transport molecules in the cell membrane.

The Norwegian company Clavis Pharma produced the azacytidine variants with modified chemical properties. Among the substances studied was CP-4200, a coupled product of azacytidine and a fatty acid (elaidic acid). CP-4200 showed particularly good results. When cancer cells in the culture dish are treated with CP-4200, the amount of methyltransferase molecules in the interior of the cells is reduced. At the same time, the methyl groups bound to the DNA of disappear and silenced tumor brakes are reactivated. The investigators assume that the elaidic acid makes it possible even for cells without special transport proteins to take up CP-4200; the substance might reach the cell interior directly through the membrane.

The effectiveness of azacytidine was previously proven only for acute myeloid leukemia. To find out whether CP-4200 shows an increased efficacy range, the investigators compared the two substances in mice suffering from another form of , acute lymphatic leukemia. In all treatment tests investigated, the effectiveness of CP-4200 was superior to that of azacytidine. "Coupling to elaidic acid improves the bioavailability of the agent without impeding its epigenetic effect," explains project leader Frank Lyko."Therefore, we see chances of reversing methylation in far more cancer patients in the future and arresting tumor growth in this way."

More information: Bodo Brueckner, Maria Rius, Maria Rivera Markelova, Iduna Fichtner, Petter-Arnt Hals, Marit Liland Sandvold and Frank Lyko: Delivery of azacytidine to human cancer cells by elaidic acid esterification increases therapeutic drug efficacy. Molecular Cancer Therapeutics, 2010, DOI: 10.1158/1535-7163.MCT-09-1202

Related Stories

Recommended for you

Alternative splicing, an important mechanism for cancer

September 22, 2017
Cancer, which is one of the leading causes of death worldwide, arises from the disruption of essential mechanisms of the normal cell life cycle, such as replication control, DNA repair and cell death. Thanks to the advances ...

'Labyrinth' chip could help monitor aggressive cancer stem cells

September 21, 2017
Inspired by the Labyrinth of Greek mythology, a new chip etched with fluid channels sends blood samples through a hydrodynamic maze to separate out rare circulating cancer cells into a relatively clean stream for analysis. ...

Drug combination may improve impact of immunotherapy in head and neck cancer

September 21, 2017
Checkpoint inhibitor-based immunotherapy has been shown to be very effective in recurrent and metastatic head and neck cancer but only in a minority of patients. University of California San Diego School of Medicine researchers ...

Whole food diet may help prevent colon cancer, other chronic conditions

September 21, 2017
A diet that includes plenty of colorful vegetables and fruits may contain compounds that can stop colon cancer and inflammatory bowel diseases in pigs, according to an international team of researchers. Understanding how ...

New kinase detection method helps identify targets for developing cancer drugs

September 21, 2017
Purdue University researchers have developed a high-throughput method for matching kinases to the proteins they phosphorylate, speeding the ability to identify multiple potential cancer drug targets.

Poliovirus therapy induces immune responses against cancer

September 20, 2017
An investigational therapy using modified poliovirus to attack cancer tumors appears to unleash the body's own capacity to fight malignancies by activating an inflammation process that counter's the ability of cancer cells ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.