New cancer target for non-Hodgkin's lymphoma

November 22, 2009

Physician-scientists from Weill Cornell Medical College have discovered a molecular mechanism that may prove to be a powerful target for the treatment of non-Hodgkin's lymphoma, a type of cancer that affects lymphocytes, or white blood cells. By exploiting this mechanism, researchers have been able to powerfully suppress tumor formation in lab testing and in animal models.

Promising results have led to the design of a clinical trial that will soon be under way to test a compound -- called PU-H71 -- in human patients. This compound is in a new class of drugs, called heat shock protein inhibitors.

Standard treatment for non-Hodgkin's lymphoma includes , chemotherapy and . Approximately 66,000 people are diagnosed in the United States each year and approximately 50 percent of patients will not be cured by current treatments.

The author's results are published online today in the prestigious journal Nature Medicine.

"We observed almost complete after treating the animals with PU-H71," says Dr. Ari Melnick, associate professor of medicine from the Raymond and Beverly Sackler Center for Biomedical and Physical Sciences at Weill Cornell Medical College. "I hope that clinical testing will have similar results for human participants."

The research team discovered that a molecule called heat shock protein 90 (Hsp90) is necessary for the functioning of a protein called BCL-6, which is known to drive the activity of lymphoma tumor cells.

BCL-6 is the most commonly involved protein in diffuse large B-cell lymphomas, which is the most common form of . Approximately 70 percent of these tumors test positive for BCL-6, making it a primary target for therapies.

Dr. Melnick and his team found that Hsp90 and BCL-6 joined together within cancer cells to form a complex. They also learned that Hsp90 binds directly to the gene responsible for producing the BCL-6 protein, which led them to believe that blocking Hsp90 would have a powerful effect on BCL-6 production within the cell and, therefore, tumor formation.

To prevent the two molecules from joining, the scientists tested the experimental drug, PU-H71, which was designed to block the activity of Hsp90. PU-H71 was developed by Dr. Gabriela Chiosis, a principal author of the study, from the Memorial Sloan-Kettering Cancer Center, in New York City. The scientific team discovered that exposing lymphoma cells to PU-H71 in laboratory experiments prevented the combination of the two molecules -- killing lymphoma cells and inhibiting new cell reproduction.

"The next step was to test the findings in an animal model to see what kind of effect PU-H71 had," explains Dr. Melnick. "We were excited to find that the treated animals' tumors decreased in both size and weight, and that the animals had a significantly prolonged survival compared with controls."

The researchers also found that PU-H71 had a very low toxicity in the animal models. Dr. Melnick believes that this may indicate that when tested in human patients, the drug will be well tolerated, with few side effects, such as damage to the bone marrow and immune system, which are common in cancer therapies.

Source: New York- Presbyterian Hospital (news : web)

Related Stories

Recommended for you

Vitamin C may encourage blood cancer stem cells to die

August 17, 2017
Vitamin C may "tell" faulty stem cells in the bone marrow to mature and die normally, instead of multiplying to cause blood cancers. This is the finding of a study led by researchers from Perlmutter Cancer Center at NYU Langone ...

Scientists develop novel immunotherapy technology for prostate cancer

August 17, 2017
A study led by scientists at The Wistar Institute describes a novel immunotherapeutic strategy for the treatment of cancer based on the use of synthetic DNA to directly encode protective antibodies against a cancer specific ...

Outdoor light at night linked with increased breast cancer risk in women

August 17, 2017
Women who live in areas with higher levels of outdoor light at night may be at higher risk for breast cancer than those living in areas with lower levels, according to a large long-term study from Harvard T.H. Chan School ...

Scientists develop blood test that spots tumor-derived DNA in people with early-stage cancers

August 16, 2017
In a bid to detect cancers early and in a noninvasive way, scientists at the Johns Hopkins Kimmel Cancer Center report they have developed a test that spots tiny amounts of cancer-specific DNA in blood and have used it to ...

Toxic formaldehyde is produced inside our own cells, scientists discover

August 16, 2017
New research has revealed that some of the toxin formaldehyde in our bodies does not come from our environment - it is a by-product of an essential reaction inside our own cells. This could provide new targets for developing ...

Cell cycle-blocking drugs can shrink tumors by enlisting immune system in attack on cancer

August 16, 2017
In the brief time that drugs known as CDK4/6 inhibitors have been approved for the treatment of metastatic breast cancer, doctors have made a startling observation: in certain patients, the drugs—designed to halt cancer ...

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.