Gene Study Reveals Clear-Cut Results For Some Melanoma Patients

Scientists from the Moffitt Cancer Center have discovered a gene expression signature (GES) in melanoma cancer patients. This gene signature indicates several different sets of cells and subsets of cells that are generally associated with positive overall survival rates in melanoma patients with this gene expression signature.

The study, published in the Journal of Nature, indicates that in melanoma patients with stage IV melanoma metastases, the 12 – chemokine gene expression signature correctly predicted the presence of a unique lymph node structure containing numerous cellular molecules that correlate to positive outcomes for many melanoma patients.

Melanoma is just one of 4 different types of skin cancer, which is the most common form of human malignancies. Melanoma is cancers that form in the melanocytes, the skin cells that make pigment, and skin cancer that forms an outer layer of the skin is called basal cell carcinoma. Skin cancer that forms in the flat cells that create the service of the skin is called squamous cell carcinoma, and skin cancer that forms in the cells that release hormones in response to signaling from the central nervous system is called neuroendocrine carcinoma.

More than 135,000 people were diagnosed with melanoma skin cancer in the United States last year, with 18,000 deaths. Mortality rates for white males was more than twice that for white females, and incidence rates for white males was 31.6 per 100,000 men. Conversely the incidence rate for African-American men was 1.1 per hundred thousand men, quite a disparity.

The study by researchers from the Moffitt Cancer Center are using the gene expression signature study findings to identify which patients will have the best possible outcomes from immunotherapy treatment.

Generally, skin cancer patients with stage IV melanoma have a reduced lifespan, most under one year. Being able to identify a biomarker that would indicate the best candidates for positive outcomes is an enormous discovery, as the shortened life span of these late stage cancer patients limits their treatment options.

“Why hold up a patient on a therapy when you don’t know if it’s going to work or not?” Said senior Moffit Cancer Center Researcher James Mulé.

The study was published in Scientific Reports, Journal of Nature online edition, on October 24, 2012.

A more recent study, published yesterday in the Journal of Nature online, indicates that melanoma cells that become resistant to Vemurafenib, the generic name for the Hoffman-La Roche drug marketed as Zelboraf.

The FDA approved the use of this drug for treatment of late stage metastatic melanoma, with the BRAF V600 Gene mutation.

The research team, from the Novartis Institutes for Biomedical Research, in conjunction with the University Hospital in Zürich, Switzerland have discovered that the mechanism that makes the melanoma cells resistant to the treatment also forces the cells to become “addicted” to vemurafenib.

Once the cells become a addicted to the treatment drug, interruption of treatment with the drug equates to cellular death, and advances positive outcomes for this devastating, late stage metastic melanoma.

Article by Jim Donahue

Sources / Links / References

http://www.nature.com/srep/2012/121024/srep00765/pdf/srep00765.pdf

http://www.moffitt.org/

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11814.html

http://cancer.ucsf.edu/

http://en.wikipedia.org/wiki/Vemurafenib

http://seer.cancer.gov/statfacts/html/melan.html

http://www.cancer.gov/statistics

http://www.cancer.gov/cancertopics/types/skin