Study examines role of DNA, HPV in oral cancer survival

Source: www.drbicuspid.com Author: DrBicuspid Staff High-risk types of human papillomavirus (HPV) are increasingly associated with oropharyngeal squamous cell carcinoma (OPSCC). However, HPV-positive OPSCC is highly curable, and patients with HPV have better survival compared with HPV-negative patients, whose cancers are usually associated with alcohol and tobacco use. To better understand the molecular mechanisms underlying these differences, Jochen Hess, PhD, and colleagues at University Hospital Heidelberg monitored changes in DNA modifications in HPV-positive and HPV-negative OPSCCs (Journal of Clinical Investigation, May 1, 2013). They applied an array-based approach to monitor global changes in CpG island hypermethylation between HPV-negative and HPV-positive OPSCCs, and identified a specific pattern of differentially methylated regions that critically depends on the presence of viral transcripts. This DNA modification pattern was significantly correlated with improved survival in three separate groups of OPSCC patients, the researchers noted. "Our study highlights specific alterations in global gene promoter methylation in HPV-driven OPSCCs and identifies a signature that predicts the clinical outcome in OPSCCs," they concluded.

Drug Designed To Restore Cell Suicide In HPV-Related Head And Neck Cancer

Article Date: 10 Apr 2013 - 1:00 PDT Source: Medical News Today  Researchers have discovered a new mechanism by which the human papilloma virus (HPV) causes head and neck cancer, and they have designed a drug to block that mechanism. Though further research is needed, the new agent might offer a safer treatment for these tumors when combined with a tapered dose of standard chemotherapy. HPV-positive head and neck cancer has become three times more common since the 1970s, and it could reach epidemic levels in the future, say researchers at the Ohio State University Comprehensive Cancer Center - Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC - James) who led the study. "We believe these findings will help meet the real need for more effective and safer therapy for a growing number of HPV-positive head and neck cancer patients," says principal investigator Dr. Quintin Pan, associate professor of otolaryngology at the OSUCCC - James. The study was published in the journal Oncogene. The research, which mainly used head and neck cancer cells, shows that a protein produced by the virus blocks a protein made by the host cell. The cell protein, called p300, regulates a gene called p53. This gene both controls cell division and protects the body against cancer by causing cells to die before they become malignant. By blocking the cell protein, HPV forces the host cell to live instead of die and to proliferate and form tumors. The prospective new drug, called [...]

2013-05-09T16:09:59-07:00May, 2013|Oral Cancer News|

Nearly 6 Percent Of Lung Cancer Tissue Samples From Non-Smokers Show Signs That HPV May Have Triggered The Tumors

Article Date: 12 Apr 2013 - 1:00 PDT Source: Medical News Today  A common virus known to cause cervical and head and neck cancers may also trigger some cases of lung cancer, according to new research presented by Fox Chase Cancer Center at the AACR Annual Meeting 2013. Examining tissue samples from lung cancer patients, the researchers found that nearly 6% showed signs they may have been driven by a strain of human papillomavirus (HPV) known to cause cancer. If HPV indeed plays a role in lung cancer in some patients, the next step is to better understand those tumors so they can be treated more effectively. "The ultimate goal," says study author Ranee Mehra, MD, attending physician in medical oncology at Fox Chase, "is to determine if we can target our therapies to the specific characteristics of these tumors." Studies from Asia have shown that lung tumors are frequently infected with HPV. The pattern makes sense, explains Mehra - the lungs are located very near the head and neck, which are known to be at risk of tumors upon exposure to some strains of HPV. To investigate, she and her colleagues examined 36 tissue samples from people diagnosed with non-small cell lung cancer who had never smoked, part of the Fox Chase Cancer Center Biosample Repository. The reason they chose non-smokers, Mehra explains, is that smoking is a major cause of lung cancer - but in non-smokers, the explanation is often less obvious. The researchers found that 4 out [...]

2013-05-09T15:55:12-07:00May, 2013|Oral Cancer News|

Rx Target Found For HPV, Hep C And Related Cancers

Article Date: 15 Apr 2013 - 0:00 PDTSource: Medical News Today New discoveries by a team of scientists at LSU Health Sciences Center New Orleans for the first time reveal the inner workings of a master regulator that controls functions as diverse as the ability of nerve cells to "rewire" themselves in response to external stimuli and the mechanism by which certain viruses hijack normal cellular processes to facilitate their replication that can ultimately lead to cancer. The research was published in the Journal of Biological Chemistry. The complex genetic programs controlling the function of cells and the organs, nerves, and tissues that they form are expressed through the concerted contributions of some 30,000 unique proteins that constitute the human genome. Coordination of these proteins is controlled by a small set of master regulators that sense the environment of the cell and alter subtle features of the genetic programs to maintain metabolic balance, called cellular homeostasis. More radical alterations in the genetic programs due to gene mutation or in response to viral or bacterial infection frequently lead to conditions that can result in cancer or developmental defects. Lead investigator Dr. Virginia Ronchi, a postdoctoral fellow, and research associate Jennifer Klein, working in the laboratory of Dr. Arthur Haas, Professor and Head of Biochemistry and Molecular Biology at the LSU Health Sciences Center New Orleans School of Medicine, focused on the E6AP enzyme. This enzyme regulates the functions of several dozen different proteins involved in key homoeostatic processes. The E6AP protein belongs [...]

2013-05-09T13:10:26-07:00May, 2013|Oral Cancer News|

When a virus causes cancer, surgical robot can help

Source: www.bizjournals.com Author: James Ritchie Dr. Keith Wilson finds robotic surgery to be a good approach for removing tumors growing deep in the throat, as I recently reported. As it turns out, such tumors are often part of an alarming trend. They’re often caused by the sexually transmitted human papillomavirus, also known as HPV. In decades gone by, oral cancer was almost always associated with tobacco and alcohol use. It was typically a disease of old men. No more. Many of Wilson’s patients are nonsmokers and very light drinkers. “I can’t tell you how surprised people get,” said Wilson, who is chief of staff at University of Cincinnati Medical Center. “We’re seeing younger, more affluent and more highly educated patients.” High-risk HPVs cause virtually all cervical cancers. They have in recent years been implicated in oropharyngeal cancers. The oropharynx is the middle part of the throat, including the soft palate, the base of the tongue and the tonsils. About 63 percent of oropharyngeal cancers, or 11,000 cases per year, are associated with HPV infection, according to the American Dental Association. They’re frequently under age 50. Fortunately for such patients, HPV-associated oropharyngeal cancers have a better prognosis than those with other causes. Wilson said that cure rates can approach 90 percent. The da Vinci surgical robot is an effective tool for removing them, he said, because its long, joined arms can go where a surgeon’s hands can’t. But the machines, made by Sunnyvale, Calif.-based Intuitive Surgical Inc., are gaining some criticism. [...]

Radiosensitive Variation Key in HPV-Positive Head and Neck Cancer

Kate JohnsonMay 01, 2013Source: medscape.com  GENEVA, Switzerland — Increased radiosensitivity likely contributes to improved outcomes in patients human papillomavirus (HPV)-positive head and neck squamous cell carcinomas (HNSCC), according to a new study. The findings point to a potential new approach that could enhance radiosensitivity further in these tumors, said Thorsten Rieckmann, PhD, from University Medical Center Hamburg Eppendorf in Germany. The study results, which he presented here at the 2nd European Society for Radiotherapy & Oncology (ESTRO) Forum, were also published online April 19 in Radiation and Oncology. The work was named 1 of 2 top-scoring abstracts at the ESTRO meeting. Dr. Rieckmann and colleagues compared a panel of 5 HPV-positive and 5 HPV-negative HNSCC cell lines, and demonstrated a statistically significant difference in average radiosensitivity between the 2 panels. However, in the HPV-positive cells, "we saw a very high variation in radiosensitivity, so clearly not every HPV-positive cell line is equally highly radiosensitive," Dr. Rieckmann told meeting delegates. "Therefore, caution should be urged when considering the deintensification of therapy via dose reduction," the researchers write. "Additional stratification within the subentity of HPV/p16-positive HNSCC may be necessary to more precisely predict individual tumor sensitivity." "Until we have molecular markers to predict radiosensitivity in HPV-positive HNSCC, pack-years of smoking, as suggested by Ang et al [N Engl J Med. 2010;363:24-35], are probably the best option," he told Medscape Medical News. The study demonstrated that a compromised DNA repair process is likely the reason behind the more favorable prognosis for patients with HPV-positive HNSCC treated [...]

2013-05-02T10:12:42-07:00May, 2013|Oral Cancer News|
Go to Top