Cancer vaccines 'could save millions'
Cancer vaccines are being developed
Anti-cancer vaccines may prevent hundreds of thousands of cancer cases every year, according to a leading German expert.
Professor Harald zur Hausan told the ECCO cancer conference in Lisbon on Monday that one in 10 cancers might never develop if vaccines are fully developed - and delivered to every country that needs them.
We currently have 10m cases of cancer a year worldwide. On that basis, it should be possible in the future to prevent around 1.25m of them
Professor Harald zur Hausen
Already, a vaccine against the virus thought to cause the vast majority of cervical cancer cases works well in animals, and appears to be safe and produce an immune response in humans.
Other viruses seem to play a role in the development of liver cancer and some lymphomas.
However, the latest research targets the human papillomavirus, implicated in cervical cancer.
In human volunteers, antibodies against HPV were 10-times higher following vaccination than after natural HPV infection.
Ahead by a nose
However, potentially one of the most significant advances is the possibility of a vaccine deliverable via a nasal spray rather than requiring injection by a trained medical worker.
One project is trying to carry the viral fragments which should trigger the immune response within another virus, called a parvovirus. Protection from HPV would be conferred by getting infected with the parvovirus.
Professor Harald zur Hausen, chairman of the managing board of the German Cancer Research Centre in Heidelberg, said: "This would be particularly suitable for tropical countries.
"If we can perfect these vaccines and apply them globally, then preventing infection by the most prevalent high-risk types of HPV could, in theory, prevent more than 300,000 cancer cases a year."
Overall, he said, the prospects for successful anti-cancer vaccines were promising. "We currently have 10m cases of cancer a year worldwide. On that basis, it should be possible in the future to prevent around 1.25m of them through vaccination.
news.bbc.co.uk
_____
Got my virii mixed up, was thinking of mononucleosis. Intersting on the nasal spray thing, though.
_____
EPSTEIN-BARR VIRUS INFECTION LINKED TO HUMAN BREAST CANCER By Shaun Griffin, PhD - WESTPORT, Aug 18 99 (Reuters Health) - Epstein-Barr virus (EBV) is present in a high proportion of invasive breast cancers and is frequently associated with more aggressive tumors, according to a paper published in the August 18th issue of the Journal of the National Cancer Institute.
Dr. Irene Joab, of INSERM in Paris, and a multinational team determined the prevalence of EBV in biopsy specimens from 100 patients with invasive breast cancers and in 30 healthy tissue samples adjacent to a subset of the tumors. They detected EBV DNA sequences in 51 of the 100 tumor biopsies, but in only 3 of the 30 healthy tissue samples. When the investigators analyzed a subset of breast tumor samples, they detected expression of the viral protein Epstein-Barr nuclear antigen 1 in a number of tumor epithelial cells, but not in normal cells. According to the report, EBV was more common in tumors that were negative for steroid hormone receptors. The virus was also detected more frequently in tumors with a high histologic grade.
The research group observed that EBV infection was associated with lymph node invasion, which suggests to them that the infection "...may be related to the high metastatic potential of the tumor." The investigators conclude that "ecause it is more frequently associated with the most aggressive tumors, EBV may play a role in their development." In an interview with Reuters Health, Dr. Joab said that "...in order to better understand the role that EBV plays in the pathogenesis of breast cancer, we are now examining precancerous lesions for the presence of the virus." She added, "Whether or not EBV is of pathogenic significance in breast cancer, it could still be a useful prognostic indicator or even provide a molecular target for therapy."
In an accompanying editorial, Drs. Ian Magrath and Kishor Bhatia, from the National Cancer Institute in Bethesda, Maryland, say that "...although more data are needed, it seems likely...that EBV is frequently associated with breast cancer." The editorialists point out that this and a number of other studies have failed to detect EBV in tumor tissue when samples were analyzed for the presence of small EBV-encoded RNA molecules called EBERs. "The variable expression of EBER in neoplastic epithelial cells...leaves open the possibility that EBV may be associated with a broader range of tumors than previously thought," Drs. Magrath and Bhatia note. J Natl Cancer Inst 1999;91:1376-1381,1349-1350.
AVIRON ANNOUNCES RESULTS OF PHASE 1 CLINICAL TRIAL FOR EPSTEIN-BARR VIRUS VACCINE -- MOUNTAIN VIEW, Calif., 8-11-99 /PRNewswire/ Aviron (Nasdaq: AVIR) announced today the completion of a Phase 1 clinical trial of an investigational vaccine against Epstein-Barr Virus (EBV), performed under its collaboration with SmithKline Beecham Biologicals. The study showed that the vaccine tested was safe and well-tolerated whether or not subjects had been exposed to EBV prior to the study. Although the study was not designed to evaluate the efficacy of the vaccine, laboratory tests showed evidence of immune response in vaccine recipients.
The trial was a randomized, double-blind study to evaluate safety and immunogenicity of two formulations of intramuscularly injected vaccines in healthy young adults. It was conducted at University Hospital of Liege, Belgium. The vaccine was administered to 67 subjects. The vaccine under development is based on the single surface antigen responsible for most of the neutralizing antibodies stimulated by EBV infection, and combines Aviron's antigen with SmithKline's proprietary adjuvant technology.
Epstein-Barr Virus belongs to the herpesvirus family and is the major cause of infectious mononucleosis. Mononucleosis affects an estimated 250,000 young adults in the U.S. and Europe annually. Sore throat and swollen neck glands are followed by a period of fatigue and lethargy which can last for weeks or months, and dramatic enlargement of the liver and spleen may require avoidance of many sports activities. (usual PR disclaimer applies) SOURCE Aviron
organtx.org |
