…has been the number one Google search term leading people to the blog this week – and that worries me.
As I wrote about a week ago, dichloroacetate, or DCA, is the molecule tested recently by a team at University of Alberta for its ability to slow the growth of human lung cancer in immunocompromised rats. Among DCA’s action is the ability to prevent cancer cells from producing lactic acid via aerobic glycolysis, a process used by more than half (but not all) tumors. Scientists continue to debate whether this process is a cause of cancer, or just a byproduct of malignant cell transformation.
I am deeply concerned that desperate cancer patients may be trying to purchase dichloroacetate (DCA) and self-treat for cancer based on this highly-hyped single paper. To the credit of the researchers and their institution, who have set up a website to address the intense interest, they discourage such practice:
At this point, the University of Alberta, the Alberta Cancer Board and Capital Health do not condone or advise the use of dichloroacetate (DCA) in human beings for the treatment of cancer since no human beings have gone through clinical trials using DCA to treat cancer. However, the University of Alberta and the Alberta Cancer Board are committed to performing clinical trials in the immediate future in consultation with regulatory agencies such as Health Canada. We believe that because DCA has been used on human beings in Phase 1 and Phase 2 trials of metabolic diseases, the cancer clinical trials timeline for our research will be much shorter than usual.
I had mentioned that one of my old profs has been studying DCA for almost 30 years as a treatment for rare metabolic diseases. One of his abstracts just reminded me of another risk of unguided use of DCA: it can be metabolized to oxalic acid, a key component of kidney stones. (For some reason, we’ve been talking a lot about kidney stones over the last few days.). Oxalic acid is also the metabolite of ethylene glycol-based automotive antifreeze that can cause renal failure and death, often in pets that lick the sweet green fluid when owners flush their car radiators.
Again, if you stumbled on this post by looking for where you can buy dichloroacetate (DCA), please do not use the substance and please consult with your oncologist if you are thinking of doing so. While DCA has been the subject of clinical trials for rare metabolic diseases, it has never been tested in cancer patients. We have no idea how DCA will affect the metabolism of other drugs, including chemotherapy, and I am concerned since high doses can have dramatic effects on systemic pH and kidney function.
I strongly support that DCA be tested against certain cancers in clinical trials and it sounds as though the Alberta group is about to do so. But also remember that this drug has only been tested against cancer cells grown in culture and against only one human tumor model in rats. This is very early in the drug development process and certainly far too early for patients to think about self-medication with DCA, particularly if they are already receiving therapies with known benefits and risks.
If not for this blog and the Google search results feature of SiteMeter, I would not have known just how widespread interest was in purchasing DCA. I hope that those of you considering such action will recognize that the effectiveness of DCA against human cancer has not been evaluated. Moreover, please recognize the damage that might be done by DCA in a cancer patient, taken with or without other drugs, has not been assessed.
I would also encourage oncology professionals to be on the lookout for cancer patients with unexplained changes in renal function or electrolytes, peripheral neuropathy, or elevated serum hepatic transaminases – as DCA is widely-available, there is a high probability that clinical professionals will be encountering patients with DCA toxicity if my search queries are any indication of the pervasiveness of interest in this as-yet untested therapy for human cancers.