 |
|
Stealth particles to target tumors
September 01, 2005Stealth nano particles may some day target tumor cells and deliver medication to specific body locations, according to Penn State chemical engineers.
"Mainly we have focused on chemotherapy drugs," says Dr. Michael Pishko, professor of chemical engineering and materials science and engineering. "But others are considering using this delivery system to deliver genes in gene therapy."
The researchers first produce nano-sized powders of the drug they wish to deliver and encapsulate them in a polymer nanoshell. The drug used for this project was paclitaxel - an anti breast cancer drug - and dexamethasone - a steroid frequently used to treat eye inflammation. This shell allows the drug to travel in stealth mode through the bloodstream.
"A layer-by-layer self-assembly technique was used to encapsulate core charged drug nanoparticles in a polymeric nanoshell," the researchers told attendees today (Aug. 31) at the 230th American Chemical Society Meeting, Washington, D.C.
Normally, drugs, especially the toxic drugs used for chemotherapy, trigger the human immune system into action, but, with the polymer shell for protection, these drugs can circulate longer without being removed.
"If the drugs do not trigger an immune response, then lower levels of drug can be used than currently are necessary in chemotherapy," says Pishko.
The researchers, who include Pishko, Alisar Zahr and Cheryl A. Rumbarger, graduate students in chemical engineering, tested their nanoshell in cell culture and found that it had less phagocytosis - removal of the drug - during a 24-hour period than the unencapsulated drug.
Combined with longer retention in the body, the researchers engineered the nanoparticle shells to target specific cells by attaching a functionalized polymer to the shell. They designed this tentacle-like projection to target a receptor on a tumor cell, or a specific location in the eye, for example. Once the drug arrives via the blood to the tumor or eye, it attaches and slowly releases its contents.
This type of drug delivery system works especially well in such highly vascularized areas such as tumors and the eye, because the drug can travel right up to the target area. Delivery to areas in the brain would not be feasible because of the blood brain barrier that prevents foreign substances from moving from the blood into the cells of the brain.
"For targeting, we could exploit the fact that cancer tumors have a lot more folic acid receptors and target those," says Pishko. "We could also use specific monoclonal antibodies to target specific tumors."
The researchers also considered delivery of drugs to specific type cells, like those in the eye. This type of stealth targeting drug delivery system could also deliver genes or gene fragments in gene therapy.
Penn State
"A layer-by-layer self-assembly technique was used to encapsulate core charged drug nanoparticles in a polymeric nanoshell," the researchers told attendees today (Aug. 31) at the 230th American Chemical Society Meeting, Washington, D.C.
Normally, drugs, especially the toxic drugs used for chemotherapy, trigger the human immune system into action, but, with the polymer shell for protection, these drugs can circulate longer without being removed.
"If the drugs do not trigger an immune response, then lower levels of drug can be used than currently are necessary in chemotherapy," says Pishko.
The researchers, who include Pishko, Alisar Zahr and Cheryl A. Rumbarger, graduate students in chemical engineering, tested their nanoshell in cell culture and found that it had less phagocytosis - removal of the drug - during a 24-hour period than the unencapsulated drug.
Combined with longer retention in the body, the researchers engineered the nanoparticle shells to target specific cells by attaching a functionalized polymer to the shell. They designed this tentacle-like projection to target a receptor on a tumor cell, or a specific location in the eye, for example. Once the drug arrives via the blood to the tumor or eye, it attaches and slowly releases its contents.
This type of drug delivery system works especially well in such highly vascularized areas such as tumors and the eye, because the drug can travel right up to the target area. Delivery to areas in the brain would not be feasible because of the blood brain barrier that prevents foreign substances from moving from the blood into the cells of the brain.
"For targeting, we could exploit the fact that cancer tumors have a lot more folic acid receptors and target those," says Pishko. "We could also use specific monoclonal antibodies to target specific tumors."
The researchers also considered delivery of drugs to specific type cells, like those in the eye. This type of stealth targeting drug delivery system could also deliver genes or gene fragments in gene therapy.
Penn State
Tumors Current Events and Tumors News RSSRare pancreatic cancer patients may live longer when treated with radiation therapy
Radiation therapy is effective in achieving local control and palliation in patients with pancreatic neuroendocrine tumors (PNTs), despite such tumors being commonly considered resistant to radiation therapy.
Researchers Identify Role of Gene in Tumor Development, Growth and Progression
Virginia Commonwealth University Massey Cancer Center and VCU Institute of Molecular Medicine researchers have identified a gene that may play a pivotal role in two processes that are essential for tumor development, growth and progression to metastasis.
New cancer target for non-Hodgkin's lymphoma
Physician-scientists from Weill Cornell Medical College have discovered a molecular mechanism that may prove to be a powerful target for the treatment of non-Hodgkin's lymphoma, a type of cancer that affects lymphocytes, or white blood cells.
New research shows versatility of amniotic fluid stem cells
For the first time, scientists have demonstrated that stem cells found in amniotic fluid meet an important test of potential to become specialized cell types, which suggests they may be useful for treating a wider array of diseases and conditions than scientists originally thought.
Engineer designs micro-endoscope to seek out early signs of cancer
Traditional endoscopes provide a peek inside patients' bodies. Now, a University of Florida engineering researcher is designing ones capable of a full inspection.
Common pain relief medication may encourage cancer growth
Although morphine has been the gold-standard treatment for postoperative and chronic cancer pain for two centuries, a growing body of evidence is showing that opiate-based painkillers can stimulate the growth and spread of cancer cells.
UCLA researchers create 'fly paper' to capture circulating cancer cells
Just as fly paper captures insects, an innovative new device with nano-sized features developed by researchers at UCLA is able to grab cancer cells in the blood that have broken off from a tumor.
'Cross-talk' mechanism contributes to colorectal cancer
Researchers at the University of Wisconsin-Madison School of Medicine and Public Health have identified a molecular mechanism that allows two powerful signaling pathways to interact and begin a process leading to colorectal tumors.
Fertility procedures need not delay breast cancer treatment for younger women
A new study published in the November issue of the Journal of the American College of Surgeons shows that breast cancer patients under 40 years old who undergo fertility preservation do not face a significant delay in the treatment of their disease when their care is coordinated in a timely fashion.
Cornell researchers identify a weak link in cancer cell armor
The seeming invincibility of cancerous tumors may be crumbling, thanks to a promising new gene therapy that eliminates the ability of certain cells to repair themselves.
More Tumors Current Events and Tumors News Articles
 |
Living with a Brain Tumor: Dr. Peter Black's Guide to Taking Control of Your Treatment by Peter Black (Author) Each year, 100,000 people in the United States are diagnosed with a brain tumor. With his new book, Dr. Peter Black fills a gap in the lay readership, providing an accessible medical resource for adult patients and their families. Dr. Black, who has operated on more than 3,000 patients with brain tumors, is uniquely qualified to discuss both clinical treatment of and research into brain tumors. This invaluable resource tells patients everything they need to know to understand and address their diagnosis, in a four-part structure: • “What is a Brain Tumor?" provides straightforward information about how brain tumors are diagnosed, the different types of tumors and how they develop, and where to go for treatment. • “Coping with Shock” addresses the emotional... |
 |
Curveball: When Life Throws You a Brain Tumor by Liz Holzemer (Author) Life seemed idyllic for thirty-two-year-old Liz Holzemer. Wife of Major League Baseball pitcher Mark Holzemer, Liz was enjoying a successful career as a journalist when an MRI revealed a baseball-size brain tumor she soon found out was called meningioma. Told with clarity and unwavering humor, this book is an inspirational and informative account of one woman’s battle for her life. It shows how she emerged from this frightening diagnosis and two brain surgeries retaining her remarkable spirit of survival and renewed sense of purpose and hope. With practical information about meningioma and brain surgery, Curveball is a manual for people who face life-altering challenges and is also proof that one need not fight such battles alone. |
 |
Seelenfresser by Tumor SPV. |
 |
Diagnostic Histopathology of Tumors: 2-Volume Set with CD-ROMs (Diagnostic Histopathology of Tumors (Fletcher)) by Christopher D. M. Fletcher MD FRCPath (Editor) Up to date and comprehensive, the New Edition of Fletcher's renowned Diagnostic Histopathology of Tumors provides you with today's best knowledge on the pathologic diagnosis of human tumors. This 3rd edition incorporates all of the latest ancillary diagnostic and prognostic techniques so you can effectively evaluate and confidently interpret suspected tumor specimens. Plus, more than 50 internationally recognized authorities and over 3,100 full-color illustrations provide you with an up-to-date account of tumor morphology, the application of modern diagnostic techniques (including molecular genetics), and key aspects of differential diagnosis. Features over 3,000 high-quality full-color illustrations, providing visual guidance to each tumor or tumor-like entity.Presents... |
 |
The Tumor Funambulist (Primary Contributor) |
 |
PIZZA TUMOR Funny Definition (Gotta See it to Believe it -TRUST ME, YOU'LL LAUGH) Ladies T-Shirt Pink Large by T-ShirtFrenzy The Design/Saying is printed on the front of this T-Shirt, we use the newest & best technology to print the design with great inks that are cured into the product. This new high tech way of producing garments is very fade resistant. WE DO NOT USE TRANSFERS. It is great, since you dont have that thick transfer feeling. The feel is very smooth and comfortable. T-ShirtFrenzy offers over 30,000 designs on tons of products to offer millions of variations. You can search our store for something for everyone on your gift list or shop for yourself (our personal favorite). Please contact us with questions. |
 |
Alternative Health & Herbs Remedies Skin Tumors (external), 1-Ounce Bottle (Pack of 2) by Alternative Health & Herbs Remedies Use externally for skin tumors, skin cancer, infection, and skin disorders. |
 |
PetAlive C-Caps and DetoxPlus ComboPack by PetAlive The PetAlive ComboPack of C-Caps and DetoxPlus consists of multiple remedies that work well together to provide increased support for your pets condition. This ComboPack is effective for cancer support and systemic cleansing. The C-Caps strengthen immune system to prevent and treat cancer while the DetoxPlus cleanses the system and eliminates toxins from the body. |
 |
Brain Tumor Awareness Ribbon Mouse Pad by MyHeritageWear.com The Brain Tumor Ribbon proudly displayed on a mouse pad. There is no better way to achieve awareness for the meaning of the Brain Tumor Ribbon than to display it on your mouse pad for everyone to see. The mouse pad measures at 9.25 x 7.75, it is machine washable, and the colors will not fade or run. Start gaining awareness today by presenting your Brain Tumor Ribbon mouse pad at work or at home. It is certain to keep your mouse rolling in style all while gaining support and awareness! |
 |
NEUROSURGERY VIDEO ATLAS SERIES I by Evandro de Oliveira, MD - Mesial Tumor - VHS 07 Also With: MD,FACS Evandro de Oliveira (Primary Contributor) VHS 07 - NEUROSURGERY VIDEO ATLAS - SERIES I Neurosurgery -Mesial Tumor This Series show us new surgical cases produced in 2002 and 2003 by Evandro de Oliveira,M.D. and Helder Tedeschi, M.D. They are all high quality videos, recorded and reproduced in digital system that guarantees the perfect image. All videos have background music that offers relaxation for the spectator. |
| © 2009 BrightSurf.com |