Nanoparticle-delivered 'suicide' genes slowed ovarian tumor growthJuly 30, 2009PHILADELPHIA - Nanoparticle delivery of diphtheria toxin-encoding DNA selectively expressed in ovarian cancer cells reduced the burden of ovarian tumors in mice, and researchers expect this therapy could be tested in humans within 18 to 24 months, according to a report in Cancer Research, a journal of the American Association for Cancer Research. Although early stage ovarian cancer can be treated with a combination of surgery followed by chemotherapy, there are currently no effective treatments for advanced ovarian cancer that has recurred after surgery and primary chemotherapy. Therefore, the majority of treated early stage cancers will relapse. "This report is definitely a reason to hope. We now have a potential new therapy for the treatment of advanced ovarian cancer that has promise for targeting tumor cells and leaving healthy cells healthy," said lead researcher Janet Sawicki, Ph.D., a professor at the Lankenau Institute for Medical Research. Sawicki and colleagues at the Massachusetts Institute of Technology evaluated the therapeutic efficacy of a cationic biodegradable beta-amino ester polymer as a vector for the nanoparticle delivery of a DNA encoding diphtheria toxin suicide gene. These nanoparticles were injected into mice with primary or metastatic ovarian tumors. To test the efficacy of this technique, the researchers measured tumor volume before and after treatment. They found that while treated tumors increased 2-fold, this was significantly less than the between 4.1-fold and 6-fold increase in control mice. Furthermore, four of the treated tumors failed to grow at all, while all control tumors increased in size. Administration of nanoparticles to three different ovarian cancer mouse models prolonged lifespan by nearly four weeks and suppressed tumor growth more effectively, and with minimal non-specific cytotoxicity, than in mice treated with clinically relevant doses of cisplatin and paclitaxel. Edward Sausville, M.D., Ph.D., an associate editor of Cancer Research and associate director for clinical research at the Greenebaum Cancer Center at the University of Maryland, said this report illustrates significant progress in targeted therapy. "In oncology we have been studying ways to kill tumors for a long time, but much of this has run up against the real estate principle of location, location, location," he said. "In other words, an effective therapy is not effective if it cannot get to the target." Sausville said a major accomplishment of this research is the multiple ways it can target ovarian cancer cells, as scientists were able to deliver diphtheria toxin genes, using a nanoparticle, to the actual tumor site (peritoneum) with a basis for selective activity in the cancer cells (how the toxin genes were regulated once inside the cells). "A real plus of a cancer therapy like this is not just the functionality of the nanoparticle construct molecule, but the ability to deliver the toxin to the tumor cells," said Sausville, who agrees that inception of clinical trials could be just 18 months away. American Association for Cancer Research |
|||||||||||||||||||||
| Related Ovarian Cancer Current Events and Ovarian Cancer News Articles FDA approved leukemia drugs shows promise in ovarian cancer cells The drug Sprycel, approved for use by the U.S. Food and Drug Administration in patients with chronic myeloid leukemia, significantly inhibited the growth and invasiveness of ovarian cancer cells and also promoted their death, a study by researchers with UCLA's Jonsson Comprehensive Cancer Center found. American Dietetic Association Releases Updated Position Paper Promoting and Supporting Breastfeeding The American Dietetic Association has released an updated position paper on breastfeeding that details health benefits for both infants and mothers and encourages promotion of breastfeeding whenever possible. Metals could forge new cancer drug Drugs made using unusual metals could form an effective treatment against colon and ovarian cancer, including cancerous cells that have developed immunity to other drugs, according to research at the University of Warwick and the University of Leeds. Breast cancer patients with high risk gene diagnosed 6 years earlier than generation before Women with a deleterious gene mutation are diagnosed with breast cancer six years earlier than relatives of the previous generation who also had the disease and/or ovarian cancer, according to new research from The University of Texas M. D. Anderson Cancer Center. Cancer Predisposition From Gene Variant Shows Strong Gender Bias Cancer predisposition resulting from the presence of a specific gene variant shows a strong gender bias, researchers at the University of Cincinnati (UC) have demonstrated. Medications Effective in Reducing Risks for Breast Cancer Can Also Cause Serious Side Effects Three drugs that reduce a woman's chance of getting breast cancer also have been shown to cause adverse effects, according to a new report from the Agency for Healthcare Research and Quality (AHRQ), U.S. Department of Health & Human Services. Scientists from University of Hawaii at Manoa find genetic marker A new genetic marker associated with ovarian cancer risk was recently discovered by an international research group, led by scientists from the Cancer Research Genetic Epidemiology Unit in the United Kingdom. New treatment in sight for ovarian cancer In the future, women with metastatic ovarian cancer could be treated with a radioactive substance that can seek and destroy tumour cells. Young early stage ovarian cancer patients can preserve fertility A new study finds that young women with early-stage ovarian cancer can preserve future fertility by keeping at least one ovary or the uterus without increasing the risk of dying from the disease. Estrogen-Dependent Switch Tempers Killing Activity of Immune Cells The sex hormone estrogen tempers the killing activity of a specific group of immune cells, the cytotoxic T cells (CTLs), which are known to attack tumor cells and cells infected by viruses. More Ovarian Cancer Current Events and Ovarian Cancer News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||