- Carbidopa, a drug used to treat Parkinson's disease (PD) has been
found to have significant anticancer properties in this current study
- Many of the current chemotherapeutic agents are associated with
severe unwanted and long lasting side effects
- Since Carbidopa is FDA approved, and found to be a safe drug,
further studies to investigate its anticancer effect merit consideration
disease drug Carbidopa
found to have anti-cancer effects and
could emerge as potential anticancer drug in the future, according to a recent study at the Texas
Tech University Health Sciences Center in the USA.
findings of the study appear in the Biochemical Journal
and could probably explain why the incidence of several cancers, except
melanoma is lower in persons with Parkinson's disease.
‘Carbidopa is an FDA approved drug used in Parkinsonís disease and further studies to assess its anticancer properties should be carried out to establish its role as an anticancer agent.’
"Carbidopa is an FDA-approved drug
for treating Parkinson's disease
clinical trials can be conducted right away to evaluate its efficacy in humans
as an anticancer drug," explained lead study author Dr Yangzom Bhutia from
Texas Tech University Health Sciences Center in the USA.
Carbidopa As Anticancer Agent - The Advantages
is an FDA approved
drug to treat
Parkinson's disease. It has been proven
to be safe and well tolerated
. Thus it would be relatively easier to
explore the role of this drug to treat cancer, while significantly reducing the
time, effort and money that would otherwise be required to be spent in
investigating a totally new drug.
Professor Aideen Sullivan from
the University College Cork is a Parkinson's disease expert who was not
involved in the research. When asked about the current study, she commented:
"With increasing interest in the
re-purposing of drugs, to reduce costs and time needed to get a drug to market,
it is timely for investigators to explore the potential anticancer properties
of anti-Parkinson's therapies."
Testing the Efficacy of
Carbidopa as Anticancer Agent
In this study, Bhutia and her team,
including collaborators from Japan and India, assessed the anticancer effects
of carbidopa on a human pancreatic cancer cell line as well as in mouse models
of pancreatic cancer.
- It was seen that carbidopa
significantly reduced growth and multiplication of cancer cells both in
the cell line as well as mice.
Although the team believes that carbidopa
could have wide ranging anticancer effects, they chose to focus on pancreatic
cancer because of the limited treatment options for this form of the disease
and poor survival and long-term prognosis.
" Pancreatic cancer
, especially the
pancreatic ductal adenocarcinoma, is the most lethal of all cancers with a
dismal survival rate," commented Bhutia. "Carbidopa as an anti-cancer
agent to treat pancreatic cancer would be something truly amazing."
"Interestingly, no one has
previously suspected carbidopa as a potential player in this phenomenon,"
said Bhutia. "Carbidopa is never used by itself as a drug for any disease.
But our data show that carbidopa by itself possesses the anticancer effect. We
believe that the reduced incidence of most cancers in Parkinson's disease
patients is due to carbidopa."
Aspect of Carbidopa - Found to be Safe
The standard dose of carbidopa for
Parkinson's disease patients is 200 mg/day, although, even a dose as high as
450 mg/day, has been found to be free of side effects. This study was not
carried out in humans; nevertheless, the
dose of carbidopa given to mice, which inhibited tumor growth was equivalent to
a dose of less than 400 mg/day in humans, which is considered to be safe
of Action of Carbidopa
(AhR) protein plays a critical role in cancer and
stimulation of this protein appears promising to treat several including
breast, colon and pancreatic cancer. Bhutia and team demonstrated that carbidopa activates AhR and believe this
may account, at least in part for its anticancer properties
The author of an accompanying commentary
to the research article Professor Stephen Safe, Texas A&M University,
remarked: "This receptor was initially identified as the critical target
that mediates the toxicity of "dioxin" and related compounds;
however, results of this study with carbidopa and several other reports are
demonstrating that the AhR is a therapeutic target not only for cancer but many
About Carbidopa - In
L-Dopa has been used to treat PD
symptoms, but associated with several adverse effects including nausea. This is
because only a very small amount of the drug (5-10%) enters the brain, while
the rest of the drug is converted to dopamine in other parts of the body,
resulting in undesirable side effects.
Carbidopa is given along with L-Dopa to
prevent the peripheral conversion of L-Dopa to dopamine i.e. in tissues outside
the brain. Fortunately, carbidopa does not enter the brain and therefore does
not interfere with L-Dopa effect in the brain.
Parkinson's disease is a
neurodegenerative disorder affecting movement and motor skills. Symptoms include shaking, stiffness and
difficulty in walking. It occurs due to reduced dopamine
production by neurons in the brain. Currently, there is no
cure and treatments aim to reduce symptoms.
- The team plans to investigate the
possibility of additional targets of carbidopa other than the aryl
hydrocarbon receptor (AhR) protein to explain its anticancer effects
- Bhutia plans to work closely with
oncologists to design and conduct clinical trials in cancer patients to
confirm whether carbidopa would be useful as an anticancer drug in humans
In conclusion, if carbidopa is approved
as an anticancer agent, it would be good news for cancer patients as well as
treating physicians. However, it would be important to first establish the
effectiveness of carbidopa in specific cancer types and conduct clinical
- Parkinson's disease drug shows anticancer effects - (https://www.eurekalert.org/emb_releases/2017-09/bs-pdd092617.php)