Gene mutation can allow proteins to gather, spark tumor growth

September 7, 2012 by Julie Deardorff

Prostate cancer is generally treated as if it's a single disease. But researchers have discovered a new type of the cancer that appears to affect 15 percent of patients, a finding that paves the way for better diagnosis and more targeted therapies down the road.

The new pathway for development was discovered after a team of scientists identified unique mutations in a gene known as SPOP (pronounced 'S-Pop') while examining patient tumors. These may lead to a dangerous accumulation of proteins that spark , forming a distinct kind of cancer, according to the study, published in the journal Nature Genetics.

The discovery of a second way for cancer to grow means we might one day "think of prostate cancer not as one disease but as a collection of molecularly defined subtypes, similar to breast and ," said Dr. Mark Rubin, vice chair for at Weill Cornell Medical College and a co-senior investigator of the study.

Along with previous research, the study is helping flesh out the overall genetic landscape of prostate cancer - the most common cancer in men with the exception of .

About one-sixth of men will be diagnosed with prostate cancer in their lifetime; two-thirds when they are older than 65. Prostate cancer is the second leading cause of cancer deaths in men.

Some speculate that the finding of an SPOP mutation may be one of the breakthroughs oncologists have been seeking. "Knowing what these mutations mean may give us huge clues about how the patient's cancer will progress and how they might be best treated in the future," said study co-author Christopher Barbieri, chief resident in urology at Weill Cornell who spent a research year in Rubin's laboratory.

About half of all prostate cancers are characterized by the presence of so-called ETS . A occurs when two genes located in different parts of the genome become attached together, leading to a new function.

The new subtype of prostate cancer is defined by two factors: the presence of a mutation in the SPOP gene and the loss of DNA in an area harboring another gene.

"Alterations in these two major gatekeepers lead to a cascade of downstream events that make these tumors distinct from other prostate cancers," said Rubin, who noted that SPOP mutations and fusion genes never occur in the same tumor, implying two distinct molecular classes of prostate cancer.

The SPOP gene belongs to a family whose job is to regulate other proteins by tagging or marking them for disposal. The team discovered the mutations occur where the SPOP protein binds to the other proteins it should tag.

"That suggests that there might be an accumulation of proteins in the cell that aren't cleaned out and this might lead to cancer growth, or the mutations could be removing proteins that help prevent unchecked cell growth," said Rubin.

Rubin predicted that within a year, men already confirmed with prostate cancer will be able to get tested to see what kind of subtype of prostate cancer they have and then receive tailor-made treatment. Rubin predicts future screening tests will include panels of such cancer specific markers to ensure accurate diagnosis of cancer.

Still, others say that although the discovery is exciting, the test wouldn't be clinically available for quite some time - if ever. Additionally, it would never be used as a screening tool because it's present in only a small portion of all prostate cancers.

Explore further: Distinct molecular subtype of prostate cancer identified

Related Stories

Distinct molecular subtype of prostate cancer identified

May 20, 2012
A collaborative expedition into the deep genetics of prostate cancer has uncovered a distinct subtype of the disease, one that appears to account for up to 15 percent of all cases, say researchers at Weill Cornell Medical ...

Prostate cancer early warning protein detected

May 31, 2012
(Medical Xpress) -- Scientists at the University have discovered a protein, only present in prostate cancer cells, that could be used as a marker to detect early signs of the disease.     

Recommended for you

Molecular changes with age in normal breast tissue are linked to cancer-related changes

July 20, 2017
Several known factors are associated with a higher risk of breast cancer including increasing age, being overweight after menopause, alcohol intake, and family history. However, the underlying biologic mechanisms through ...

Immune-cell numbers predict response to combination immunotherapy in melanoma

July 20, 2017
Whether a melanoma patient will better respond to a single immunotherapy drug or two in combination depends on the abundance of certain white blood cells within their tumors, according to a new study conducted by UC San Francisco ...

Discovery could lead to better results for patients undergoing radiation

July 19, 2017
More than half of cancer patients undergo radiotherapy, in which high doses of radiation are aimed at diseased tissue to kill cancer cells. But due to a phenomenon known as radiation-induced bystander effect (RIBE), in which ...

Definitive genomic study reveals alterations driving most medulloblastoma brain tumors

July 19, 2017
The most comprehensive analysis yet of medulloblastoma has identified genomic changes responsible for more than 75 percent of the brain tumors, including two new suspected cancer genes that were found exclusively in the least ...

Novel CRISPR-Cas9 screening enables discovery of new targets to aid cancer immunotherapy

July 19, 2017
A novel screening method developed by a team at Dana-Farber/Boston Children's Cancer and Blood Disorders Center—using CRISPR-Cas9 genome editing technology to test the function of thousands of tumor genes in mice—has ...

How CD44s gives brain cancer a survival advantage

July 19, 2017
Understanding the mechanisms that give cancer cells the ability to survive and grow opens the possibility of developing improved treatments to control or cure the disease. In the case of glioblastoma multiforme, the deadliest ...

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.