Biomarker predicts chemo response for osteosarcoma

July 3, 2012

(Medical Xpress) -- Scientists have found that a protein expressed by some cancers is a good predictor of how the cancer will respond to standard chemotherapy for osteosarcoma, the most common bone cancer in children. Knowing whether a patient's tumor has this protein biomarker could help doctors determine if a patient should undergo standard treatment or if a more aggressive or alternative therapy may be more effective.
The study findings were published in Human Pathology.

"This is the first time that a biomarker has been identified that predicts for osteosarcoma," said Dariusz Borys, assistant professor in the UC Davis Department of Pathology and Laboratory Medicine and lead author of the study. "It is a first step in individualizing therapy to maximize success based on a protein that the cancer expresses."

Osteosarcoma is usually diagnosed during the . It also may affect people over 60.

Osteosarcoma is typically treated with "neoadjuvant therapy," which involves several cycles of using a combination of drugs to shrink the tumor before it is surgically removed. How effective the chemotherapy is in inducing cancer () is the best predictor of a patient's survival following surgery. But a tumor's response to chemotherapy varies widely among patients and, until now, a way to predict whether the chemotherapy will work well has not been identified.

The investigators focused on a protein expressed by cancer cells known as , which inhibits cell growth. For unknown reasons, some cancers stop expressing P16. The researchers found that patients who had cancers that still expressed P16 were more likely to respond well to chemotherapy.

"It is useful to know ahead of time if patients are likely to respond to standard therapy," said Borys. "Those who have tumors that do not express P16 would be especially good candidates for more aggressive or experimental treatments to see if they might respond better."

The study enrolled 40 patients, aged 9 to 75 years old (median age, 15 years), with osteosarcoma at UC Davis and UC San Francisco. Pathologic specimens of the tumors before treatment were collected for study from each patient and were analyzed for P16 expression. After chemotherapy, during surgery to remove the tumor, specimens were again collected and analyzed for the extent of tumor cell death. A little more than half of the patients responded well to chemotherapy, and these patients were found to be significantly more likely to have had tumors that expressed the P16 protein.

Data on how the patients fared clinically were not available for this study, but it has been well established from other studies that the amount of tumor killed preoperatively is strongly associated with survival.

Borys said more patients will be studied to strengthen the findings, and on a molecular level, more study is needed to clarify why some stop expressing P16.

The study was a collaboration among three institutions on the West Coast (UC Davis, UC San Francisco and University of Washington) and involved pathologists and surgeons. According to Borys, pathologists traditionally have been used to help establish a diagnosis, but are now moving toward an equally important role in helping clinicians determine treatment strategies.

"Pathologists will one day be able to provide answers to better help clinicians cure their patients," said Borys. "Our work to improve the treatment of osteosarcoma is an important step in that direction."

Explore further: Genetic predictor of breast cancer response to chemotherapy

More information: The article is titled, "P16 expression predicts necrotic response among patients with osteosarcoma receiving neoadjuvant chemotherapy." www.ncbi.nlm.nih.gov/pubmed/22578565

Related Stories

Genetic predictor of breast cancer response to chemotherapy

May 10, 2012
Chemotherapy is a major first line defense against breast cancer. However a patient's response is often variable and unpredictable. A study published in BioMed Central's open access journal BMC Medical Genomics shows that ...

New study finds compounds show promise in blocking STAT3 signaling as treatment for osteosarcoma

April 11, 2011
A study appearing in the journal Investigational New Drugs and conducted by researchers at Nationwide Children's Hospital, discovered that two new small molecule inhibitors are showing promise in blocking STAT3, a protein ...

Chemotherapy is as effective before breast cancer surgery as after

September 8, 2011
Whether chemotherapy is given before or after breast-conserving therapy (BCT) does not have an impact on long-term local-regional outcomes, suggesting treatment success is due more to biologic factors than chemotherapy timing, ...

Research finding suggests way to make bladder cancer cells more susceptible to chemotherapy

June 29, 2011
Researchers at the UC Davis Cancer Center have discovered a way of sensitizing muscle-invasive bladder cancer cells so that they succumb to the toxic effects of chemotherapy. The finding adds to mounting evidence that tiny ...

Study identifies genes linked to resistance to breast cancer chemotherapy

June 11, 2012
A study led by Vanderbilt-Ingram Cancer Center (VICC) investigators has identified a gene expression pattern that may explain why chemotherapy prior to surgery isn't effective against some tumors and suggests new therapy ...

Recommended for you

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 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 ...

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 ...

Researchers find 'switch' that turns on immune cells' tumor-killing ability

August 16, 2017
Molecular biologists led by Leonid Pobezinsky and his wife and research collaborator Elena Pobezinskaya at the University of Massachusetts Amherst have published results that for the first time show how a microRNA molecule ...

Popular immunotherapy target turns out to have a surprising buddy

August 16, 2017
The majority of current cancer immunotherapies focus on PD-L1. This well studied protein turns out to be controlled by a partner, CMTM6, a previously unexplored molecule that is now suddenly also a potential therapeutic target. ...

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.