This is Why We Need Serious Health Reform in the U.S.

October 21, 2009 | Filed Under health, health insurance, musings | No Comments

HPV Linked to Rare Head and Neck Cancer

October 15, 2009 | Filed Under HPV, Head and Neck, cancer, research | No Comments

An increase in cases of a rare type of head and neck cancer appears to be linked to HPV, or human papillomavirus, according to a new study from researchers at the University of Michigan Comprehensive Cancer Center.

The study looked at patients with nasopharyngeal cancer, a tumor that grows behind the nose and at the top of the throat, above the tonsils. This rare cancer occurs in less than 1 of every 100,000 Americans.

"Though rare, this is the first report of nasopharyngeal cancer being caused by the HPV epidemic. We are in the middle of a tonsil cancer epidemic, seeing many patients with tonsil cancer linked to HPV. It turns out that HPV may also be a new cause of this rare form of cancer that occurs in this hidden location," says study author Carol Bradford, professor and chair of otolaryngology at the U-M Medical School.

In the study, which appears online Wednesday in the journal Head & Neck, the researchers looked at tissue samples taken before treatment for either nasopharyngeal cancer or tonsil cancer. Of the 89 patients in the study, five had nasopharyngeal cancer, and four of those were positive for HPV.

At the same time, the four HPV-positive tumors were also all negative for Epstein-Barr virus, which has previously been one of the biggest infectious causes of nasopharyngeal cancer.

"Since I began studying head and neck cancer, I have wondered what the cause of Epstein-Barr virus-negative nasopharyngeal tumors might be. This research suggests that there is a changing etiology for nasopharyngeal cancer in the North American population that may mirror the HPV-positive epidemic of tonsil cancer," says study author Thomas Carey, professor of otolaryngology and pharmacology and co-director of the head and neck oncology program at the U-M Comprehensive Cancer Center.

Overall, about 60 percent of nasopharyngeal cancer patients are alive five years after treatment. In fact, death rates for this type of cancer have declined four percent per year. The researchers suspect one potential reason is that HPV-related tumors are more responsive to chemotherapy or radiation than tumors linked to the Epstein-Barr virus.

Because nasopharyngeal cancer is so rare, the authors propose a multi-center trial to recruit more patients to verify the role of HPV in nasopharyngeal cancer.

New Cancer Genes Discovered

October 14, 2009 | Filed Under cancer, research | No Comments

U.S. researchers has identified 231 new genes associated with head and neck cancer, one of the most deadly cancers responsible for 2.1 percent of all cancer deaths in the United States, according to results from a study, which were presented Sunday at the American Academy of Otolaryngology-Head & Neck Surgery Foundation’s annual meeting in San Diego.

Previously, only 33 genes were reported associated with head and neck cancer.

“These new genes should advance selection of head and neck- specific gene targets, opening the door to promising new molecular strategies for the early detection and treatment of head and neck cancer,” says study lead author Maria J. Worsham, director of research in the Department of Otolaryngology at Henry Ford Hospital in Detroit, Michigan. “It also may offer the opportunity to help monitor disease progression and a patient’s response to treatment.”

In 2009, more than 55,000 Americans will develop head and neck cancer, which includes cancers of the mouth, nose, sinuses, salivary glands, throat and lymph nodes in the neck; nearly 13,000 of them will die from it. According to the National Cancer Institute, 85 percent of head and neck cancers are linked to tobacco use. People who use both tobacco and alcohol are at greater risk for developing these cancers than people who use either tobacco or alcohol alone.

Treatment for head and neck cancer varies based on the location and stage of the tumor, but most often includes surgery, radiation therapy or chemotherapy.

To identify new genes that could ultimately aid in future diagnosis and treatment of head and neck cancer, Worsham’s study used a whole-genome methylation approach to detect genes with altered promoter gene regions due to DNA methylation. DNA methylation — a type of chemical modification of DNA where a methyl group (CH3) can be added (hypermethylation) or removed ( hypomethylation) — allows the researchers to look for genetic abnormalities within tumor samples.

Using five DNA samples from tumor tissue, the researchers looked for 1,043 possible cancer genes. Those genes were cross- examined with those already reported in PubMeth, a cancer methylation database. Of the 441 genes in the database, only 33 genes were referenced in connection with head and neck cancer.

In all, the whole-genome methylation approach revealed 231 potential new genes not previously reported in head and neck cancer. Of those, 50 percent were present in three or more of the DNA samples, and 20 percent were represented in all five samples.

“DNA methylation is emerging as one of the most promising molecular strategies for early detection of cancer, independent of its role in tumor development,” says Worsham. “Abnormal methylation can result in shutting off or silencing gene function. However, treatment with more recent drugs can reverse abnormal DNA methylation patterns, reactivating silenced genes, and restoring normal gene function. Therefore, a validated head and neck cancer- specific gene panel is likely to signify potential demethylation treatment targets.”