Flavonoid compound kills leukemia cells

[Guest guest]

[lef.org]

 

Flavonoid compound kills leukemia cells

 

A report published online on March 20, 2007 in The Journal of Biological

Chemistry described the finding of a team at the University of

Pittsburgh that an anthocyanidin known as cyanidin-3-rutinoside shows

the ability to kill leukemia cells in culture while leaving healthy

cells unharmed. Anthocyanins, one of the six subclasses of flavonoids,

are polyphenol compounds that naturally occur in red wine and many

fruits and vegetables, and which have antioxidant, antimutagenic, and

anticarcinogenic benefits.

 

University of Pittsburgh School of Medicine school associate professor

of pathology Xiao-Ming Yin, MD, PhD and colleagues tested

cyanidin-3-rutinoside (C-3-R), extracted from black raspberries, in

leukemia and lymphoma cell lines. Low doses of C-3-R caused programmed

cell death known as apoptosis in half of the cells in one human leukemia

cell line within about 18 hours of treatment. When the concentration of

the compound was doubled, almost all of the cancerous cells became

apoptotic. C-3-R was also demonstrated to be effective in other human

leukemia and lymphoma cell lines.

The team found that C-3-R induced the accumulation of a reactive form of

oxygen known as peroxides which activated an apoptotic pathway mediated

by the cells & rsquo; mitochondria. However, this phenomenon failed to

occur when the researchers treated normal human blood cells with the

compound. Since previous research with C-3-R has shown that it has

strong antioxidant activities characteristic of other polyphenols such

as green tea, the ability to induce oxidative stress in tumor cells

suggests selective toxicity.

& ldquo;Current treatments for leukemia, such as chemotherapy and

radiation, often damage healthy cells and tissues and can produce

unwanted side effects for many years afterward. So, there is an

intensive search for more targeted therapies for leukemia

worldwide, & rdquo; Dr Yin stated. & ldquo;Because this compound is widely

available in foods, it is very likely that it is not toxic even in

purified form. Therefore, if we can reproduce these anticancer effects

in animal studies, this will present a very promising approach for

treating a variety of human leukemias and, perhaps, lymphomas as

well. & rdquo;

 

Health Concern

Leukemia

 

Leukemia can be classified into four major types based on whether the

disease is acute or chronic and according to the type of white blood

cell affected:

 

Acute myelogenous leukemia (AML)

 

Chronic myelogenous leukemia (CML)

 

Acute lymphocytic leukemia (ALL)

 

Chronic lymphocytic leukemia (CLL)

 

Myelogenous leukemia involves myeloid cells, granulocytes (neutrophils,

basophils, and eosinophils) and monocytes (macrophages). Lymphocytic

leukemia involves T and B cells (lymphocytes).

 

Resveratrol, a plant polyphenol found in grapes and red wine, has been

shown in scientific studies to inhibit the growth of leukemia cell

lines. Resveratrol reduces the growth of AML cell lines and causes death

in HL-60 leukemia cells (Su JL et al 2005). Resveratrol has been shown

to block the proliferation of fresh AML cells taken from the bone marrow

of five newly diagnosed patients (Asou H et al 2002; Estrov Z et al

2003). Exposure of the leukemia cell line U937 to concentrations of

resveratrol similar to those found in red wine blocked cell

proliferation but, in this case, did not increase cell death of these

abnormal cells (Castello L et al 2005).

 

http://www.lef.org/protocols/cancer/leukemia_01.htm