January 15, 2007, 4:58 AM CT
Dual Gene Therapy Suppresses Lung Cancer
Combination gene treatment delivered in lipid-based nanoparticles drastically reduces the number and size of human non-small cell lung cancer tumors in mice, scientists at The University of Texas M. D. Anderson Cancer Center and the University of Texas Southwestern Medical Center report in the Jan. 15 edition of Cancer Research.
Two tumor-suppressing genes given intravenously reduced cancer separately but had their most powerful effect when administered together, cutting the number of tumors per mouse by 75 percent and the weight of tumors by 80 percent.
"In cancer therapy we have combination chemotherapy, and we also combine different modes of treatment - surgery, radiation and chemotherapy. Now you've got the possibility of combined targeted gene treatment," said Jack Roth, M.D., professor and chair of the M. D. Anderson Department of Thoracic and Cardiovascular Surgery and a senior researcher on the project.
The genes wrapped in the nanoparticles were p53, a well-known tumor suppressor that works by causing defective cells to commit suicide and is often shut down or defective in cancer cells, and FUS1, a tumor-suppressor discovered by the research group that is deficient in most human lung cancers. Each nanoparticle carried one of the two genes.........
Posted by: Scott Read more Source
January 15, 2007, 4:54 AM CT
Marker For Aggressive Form Of Breast Cancer
Researchers have linked a structural protein called nestin to a particularly deadly form of breast cancer, identifying a new biomarker that could lead to earlier detection and better treatment.
In the January 15 issue of Cancer Research, researchers from Dartmouth Medical School demonstrate that nestin could represent a selective biological marker for basal epithelial breast tumors, a highly aggressive cancer with similarities to mammary stem cells, the regenerative cells believed to be the site of breast cancer initiation.
"Patients with this type of breast cancer are at high risk for recurrence," said James DiRenzo, Ph.D., assistant professor at Dartmouth Medical School. "Ideally, a marker like nestin would enable clinicians to monitor these patients through frequent tests of a biomarker and, in doing so, detect the cancer before it has a chance to come back".
Basal epithelial tumors lack important molecular targets such as the estrogen receptor, progesterone receptor and Her2. This not only makes positive diagnosis difficult, say researchers, but also eliminates several important lines of therapy, such as tamoxifen or Herceptin, that work well for other breast cancer subtypes.
"Currently, there is no direct means of determining if a breast cancer is a basal epithelial tumor - doctors only know for certain once the other forms of breast cancer are ruled out," DiRenzo said. "This type of breast cancer is generally difficult to manage, but several important studies have shown that it is more likely than other breast cancer subtypes to respond to certain types of therapy, which highlights the need for a definitive diagnostic marker".........
Posted by: Janet Read more Source
January 12, 2007, 4:46 AM CT
High-Power MRI in Unusual Tumor Cases
A Mayo Clinic surgical team has observed that using a 3-Tesla MRI in surgical decision making provides a new level of capability to predict surgical outcomes that improves patient care by minimizing the potential for unsuccessful tumor-removal surgeries. The Mayo Clinic report appears in the recent issue of the Journal of Neurosurgery www.thejns-net.org/jns/issues/current/toc.html.
In their report, Mayo physicians describe a case study of five patients. Four had neurofibromatosis, a condition with a predisposition to nerve-related tumors. All patients suffered from growths called "sciatic notch dumbbell-shaped" tumors. The tumors were benign, but resulted in neurologic dysfunction and disabling pain.
"In the past, if surgeons couldn't tell previous to surgery where the exact location of the large tumor was in relation to the sciatic nerve, it meant they couldn't predict in which cases surgery could be performed safely," explains Robert Spinner, M.D., the lead neurosurgeon on the Mayo Clinic team.
The team used an advanced magnetic resonance imaging (MRI) system performed on a 3-Tesla magnet to help identify suitable candidates for a difficult tumor-removal surgery. A Tesla is a unit of magnet strength. A 3-Tesla is one of the strongest commercially available.........
Posted by: Janet Read more Source
January 12, 2007, 4:43 AM CT
Novel Radiation Technique To Treat Liver Cancer
Physicians at Mayo Clinic are now using tiny glass bubbles filled with radioactive material to deliver high doses of tumor-killing radiation directly to liver tumors. They say the procedure is better tolerated than other forms of intra-arterial liver cancer therapys, and may be the best option for some patients who aren't candidates for other therapys, including surgery or liver transplantation.
The technique, called either radioembolization or intra-arterial brachytherapy, uses the blood supply to send the little spheres, smaller in diameter than a human hair, into the newly formed, microscopic vessels that feed cancer. They eventually become lodged at the tumor sites where they deliver a high dose of radiation.
And because these liver tumors use a supply of blood that is largely separate from the blood that nourishes normal liver tissue, few of the microspheres end up in the healthy liver, Mayo clinicians say.
"The technique is a clever way of exploiting the differences in blood supply between the liver tumor and normal liver tissue," says Mayo Clinic interventional radiologist Ricardo Paz-Fumagalli, M.D. He, along with Mayo Clinic radiation oncologists, deliver the treatment to patients.
There are two primary blood vessels that bring blood to the liver. Normal liver tissue receives about three-fourths of its blood supply from the portal vein and only about one-fourth from the hepatic artery and its branches, explains Paz-Fumagalli. Liver tumors, conversely, get most of their life-sustaining blood supply from the hepatic artery and absorb a greater proportion of the radioactive microspheres. "So if you give a therapy through the arteries, it more specifically hits the tumor, and the normal liver is relatively spared," he says.........
Posted by: Janet Read more Source
January 10, 2007, 4:31 AM CT
Cancer-related Gene Critical For Placenta Development
An important cancer-related gene may play a critical role in the development of the placenta, the organ that controls nutrient and oxygen exchange between a mother and her fetus during pregnancy, and perhaps in miscarriages.
Those conclusions come from a new study of the retinoblastoma (Rb) gene in mice. In humans, this gene, when mutated, raises the risk of a rare cancer of the eye called retinoblastoma. Two decades ago, it was identified as the first tumor-suppressor gene, a class of genes that protects cells from becoming cancerous. It has since been shown to be inactivated in many cancers.
In this study, researchers shut off the Rb gene in stem cells that give rise to most of the placenta, resulting in an abnormal placenta and death of the embryos.
The findings provide new insights into development of the placenta and into how the Rb gene blocks tumor growth.
They also raise the possibility that this important tumor-suppressor gene might play a role in miscarriages.
The study, led by researchers at the Ohio State University Comprehensive Cancer Center, is published in the January 2007 issue of the journal Genes and Development.
"Our findings strongly suggest that the Rb gene is important in the development of the placenta, but they have other important implications, as well," says principal investigator Gustavo Leone, assistant professor of molecular virology, immunology and medical genetics and a researcher with Ohio State's Comprehensive Cancer Center and human cancer genetics program.........
Posted by: Emily Read more Source
January 9, 2007, 9:38 PM CT
Pancreatic Cancer Surgery Five-Year Survivors
A new study shows that pancreas cancer patients 65 or older who live at least five years after surgery have nearly as good a chance as anyone else to live another five years.
Scientists at the Kimmel Cancer Center at Thomas Jefferson University and Thomas Jefferson University Hospital in Philadelphia evaluated the records of 890 patients with pancreas cancer who underwent the standard pancreaticoduodenectomy, or Whipple procedure, which entails the removal of the gallbladder, common bile duct, part of the duodenum, and the head of the pancreas, between 1970 and 1999 at Johns Hopkins University. They identified those who lived for five years, and compared those who lived for at least an additional five years to the "actuarial" - or estimated - survival of the general population beginning at age 70.
Reporting in the journal Surgery, they observed that 201 patients (23 percent) lived five years after surgery, at least half of whom were 65 years old or older at the time of surgery. Of those five-year survivors, an estimated 65 percent lived at least an additional five years. In the general population, roughly 87 percent of the same age group live another five years.
The study has an important message, says Charles Yeo, M.D., Samuel Gross Professor and Chair of Surgery at Jefferson Medical College, who led the work. "A decade ago, a number of clinicians thought that there was little reason to operate on patients with pancreatic ductal cancer, that surgery does little to extend life and improve the quality of life," says Dr. Yeo. "Not too long ago, few lived for five years after diagnosis. Today that's not true. There's been a paradigm shift in the way we treat and think about this disease."........
Posted by: Sue Read more Source
January 8, 2007, 9:14 PM CT
New Cancer Drugs
Combining synthetic chemistry techniques with a knowledge of the properties and actions of enzymes, researchers have been able to produce an exciting class of anti-cancer drugs originally isolated from blue-green algae.
This accomplishment is expected to make it possible to produce enough of the promising drugs for use in clinical trials.
In a study featured on the cover of the recent issue of the journal ACS Chemical Biology, a scientific team lead by University of Michigan Life Sciences Institute Research Professor David H. Sherman and researcher Zachary Q. Beck found the trick to turning the green gunk into gold-cancer fighting gold.
"It was simply too difficult to use the native blue-green algae for high-level production using traditional fermentation approaches," said Sherman. But the compound, called cryptophycin 1, held so much promise as an anti-cancer drug that organic chemists got busy trying to find ways to make a synthetic form of the compound in large enough quantities for clinical trials.
Developing an efficient synthetic route to natural product compounds and their analogs is often an essential step in drug development. With drugs such as penicillin and tetracycline, it can easily be done, but cryptophycins present more of a challenge. Sherman's team realized that with all cryptophycins, the most difficult step came very late in the synthesis, at the point at which a key part called an epoxide-a highly strained, three-membered ring oxygen-containing group, crucial for the drug's anti-cancer activity-becomes attached to the molecule.........
Posted by: Janet Read more Source
December 26, 2006, 8:03 PM CT
Stem Cells As Cancer Therapy
It is widely hoped that neural stem cells will eventually be useful for replacing nerves damaged by degenerative diseases like Alzheimer disease and multiple sclerosis. But there may also be another use for such stem cells--delivering anti-cancer drugs to cancer cells.
A Perspective article in PLoS Medic ine, by Professor Riccardo Fodde (Erasmus Medical Center, The Netherlands), discusses a new study in mice, reported in the launch issue of PLoS ONE (www.plosone.org), that showed that neural stem cells could be used to help deliver anti-cancer drugs to metastatic cancer cells.
One of the characteristics of neural stem cells is their tendency to move towards diseased areas (researchers call this phenomenon "pathotropism"). This characteristic, says Professor Fodde, "makes them especially attractive candidates not only to replace damaged tissue in degenerative pathologies, but also to deliver therapeutic molecules in patients with disseminated metastatic cancer".
In the study published in PLoS ONE, Karen Aboody and his colleagues report on the eradication of disseminated metastases in a mouse model of a cancer called neuroblastoma. The scientists took advantage of the tumor-tropic (selective migration towards cance r cells) properties of neural stem cells engineered to express an enzyme that activates an anti-cancer drug.........
Posted by: Janet Read more Source
December 26, 2006, 8:00 PM CT
Profiling Of Cancer Genes
Dr. John Minna (left) and Deborah Moncrief Jr
Credit: UT Southwestern Medical Center
A research team at UT Southwestern Medical Center has for the first time identified several genes whose expression is lost in four of the most common solid human cancers - lung, breast, prostate and colon cancer.
The findings, which scientists say could form the basis for a new early detection screen for certain cancers, are published recently in the online journal Public Library of Science Medicine.
The expression of genes that inhibit cancer development, so-called tumor suppressor genes, is often lost in tumor cells. This can occur through a mutation in the gene's DNA sequence or through deletion of the gene. Loss of tumor suppression function also can occur in a process called methylation, where a chemical called a methyl group is attached to a DNA region near the gene and prevents it from being activated, essentially "silencing" the gene.
"These results show the power of studying tumors on a genome-wide basis, looking at a number of genes at the same time," said Dr. John Minna, the study's senior author and director of the W.A. "Tex" and Deborah Moncrief Jr. Center for Cancer Genetics and the Nancy B. and Jake L. Hamon Center for Therapeutic Oncology Research at UT Southwestern.
In an effort to identify new tumor-suppressor genes that might be important to lung and breast cancer development, the UT Southwestern team examined which genes are active in those kinds of tumors and compared them to gene expression profiles from normal lung epithelial cells. The scientists then examined the gene expression profiles of these various cell types before and after therapy with a drug that inhibits methylation.........
Posted by: Janet Read more Source
December 23, 2006, 7:31 AM CT
Incredible Story Of Paul Kraus
What would be more inspiring for mesothelioma patients than listening to the longest mesothelioma survivor in the world? Do you know Paul Kraus? He is the inspiration behind a number of patients with the diagnosis of one of the deadliest forms of cancer called mesothelioma. I have been personally moved by his story.
It was in one those days in June 1997, Paul Kraus was diagnosed with mesothelioma. That has changed his world forever. The cancer was so widespread that he was told there was little hope and that he should go home and get his affairs in order. Fearful and depressed, but not ready to give up, he researched various therapy options. Unlike a number of Paul was not willing to give an unconditional surrender to the one of the most devastating forms of cancer. With the help of his doctors and family, Paul Kraus created his own remarkable path to healing. Today, over nine years later, he continues to enjoy a good quality of life.
"Dr. Andrew Weil wrote that any illness can be conquered through radical lifestyle change because our bodies are made with powerful self-healing capacities. It was hard to make such radical changes, but I was determined to see them through," Paul Kraus said.
During this teleconference, mesothelioma patients and their loved ones can listen to Mr. Kraus summarize his knowledge and insight into this disease. He will discuss how he handled his diagnosis, what he learned about the cancer, and the steps he took to heal his mesothelioma. Subjects include: chemotherapy, surgery, holistic approaches, integrative therapies, vitamins and other supplements, traditional Chinese medicine, mind-body medicine, doctor-patient relationships, and more. Participants can also ask questions of Mr. Kraus and share information and knowledge with each other.........
Posted by: Scott Permalink Source