MedicineWorld.Org
Your gateway to the world of medicine
Home
News
Cancer News
About Us
Cancer
Health Professionals
Patients and public
Contact Us
Disclaimer

Medicineworld.org: Attack breast cancer cells from the inside out

Back to breast cancer blog Blogs list Cancer blog  


Subscribe To Breast Cancer Blog RSS Feed  RSS content feed What is RSS feed?

Attack breast cancer cells from the inside out




Throwing stones at castle walls is one way to attack an enemy, but sneaking inside makes the target much more vulnerable.

Scientists at Cedars-Sinai's Maxine Dunitz Neurosurgical Institute have employed a similar strategy using a mouse model to target important mechanisms inside the most challenging breast cancer cells. Earlier studies at Cedars-Sinai found a similar approach effective in attacking cancerous brain tumor targets.



Attack breast cancer cells from the inside out

Unlike other drugs that target cancer cells from outside and often injure normal cells as a side effect, this treatment consists of multiple drugs chemically bonded to a "transport vehicle." The drugs bypass healthy cells, accumulate inside tumor cells and attack molecular targets that enable cancer cells to grow and spread. Studies using a mouse model show this highly targeted approach, using combinations of drugs, to be more effective than standard therapy methods.

This research targeted HER2-positive breast cancer � a type that, due to a genetic mutation, makes excessive amounts of a protein that promotes the growth of cancer cells. HER2-positive breast cancers tend to be more aggressive and less responsive to therapy than other breast cancers.

One usually used antitumor drug, trastuzumab (Herceptin�), is sometimes beneficial, but with advantages and disadvantages. It is an antibody to the HER2 antigen, which means it naturally seeks out this protein in cancers. But its effectiveness as a therapy commonly is limited because in 66 to 88 percent of patients, the tumors become resistant within the first year of therapy. Herceptin also can injure normal organs it contacts.

The scientists published in their recent studies, published in a recent issue of Cancer Research, that the new drug carried multiple molecular components, each with a distinct role. These key components included: Herceptin to target the existing HER2 protein; another molecule to attack a genetic mechanism responsible for the production of new protein; and a molecule to open tumor blood vessels and deliver the drugs into the cancer cells for release. Injected into mice with implanted human breast cancer cells, the drugs accumulated in the cancer cells and worked together to significantly reduce tumor growth.

The drug is in an emerging class called nanobiopolymeric conjugates, or nanoconjugates.

"Nanobiopolymers enhance cancer cell targeting and therapy in several ways: Certain antibodies can be attached to precisely target proteins in tumor cells; drug resistance and systemic side-effects are reduced because drugs are 'bound' to the platform and delivered to the interior of cancer cells without affecting healthy cells; and multiple drugs can be carried on a single platform, making it possible to simultaneously attack several targets," said Julia Y. Ljubimova, M.D. Ph.D., senior author of an article in a recent issue of Cancer Research. She directs the Drug Delivery and Nanomedicine Laboratory in the Department of Neurosurgery at Cedars-Sinai.

Nanoconjugates are the latest evolution of molecular drugs designed to enter cells and alter defined targets within them. As suggested by the term "bioconjugate," these systems contain chemical "modules" attached (conjugated) to a delivery vehicle by strong chemical bonds. The nanoconjugate exists as a single chemical unit and the tight bonds prevent the components from getting damaged or separated in tissues or blood plasma during transit. With inventive drug engineering, the antitumor components activate inside tumor cells.

The ultimate assault on a tumor cell depends on a complex, well-choreographed chain of biochemical events, such as: specifically homing to tumor cells; permeating the walls of blood vessels and tumor cells; releasing antitumor drugs at the right place and time; and dismantling mechanisms that help tumor-feeding blood vessels grow.

"Based on our studies, our nanobioconjugate may be a safe and efficient delivery platform that appears to be tailored to treat a wide array of disorders. It is harmlessly degraded to carbon dioxide and water, nontoxic to normal tissue, and, unlike some drugs, it is non-immunogenic, meaning it does not stimulate the immune system to the point of causing allergic reactions, which may range from mild coughs or rashes to sudden, life-threatening symptoms," Ljubimova said.


Posted by: Janet    Source




Did you know?
Throwing stones at castle walls is one way to attack an enemy, but sneaking inside makes the target much more vulnerable. Scientists at Cedars-Sinai's Maxine Dunitz Neurosurgical Institute have employed a similar strategy using a mouse model to target important mechanisms inside the most challenging breast cancer cells. Earlier studies at Cedars-Sinai found a similar approach effective in attacking cancerous brain tumor targets.

Medicineworld.org: Attack breast cancer cells from the inside out

BREAST CANCER MAIN| Home| Breast cancer news| Common terms| Breast cancer treatment| Breast cancer treatment by stage| Mammogram and breast cancer screening| Surgical treatment of breast cancer| Chemotherapy of breast cancer| Chemo drugs used in breast cancer| Doxorubicin| Cyclophosphamide| Methotrexate| Hormonal therapy of breast cancer| Radiation therapy of breast cancer| Monoclonal therapy| High dose chemotherapy for breast cancer| Recurrent breast cancer| Bisphosphonates and breast cancer| Pregnancy and breast cancer| Risk factors for breast cancer| Risk details| My risk| Comprehensive breast cancer information| Breast cancer statistics| African Americans and breast cancer| Ashkenazi and breast cancer| Asians| Hispanic| Men| Native Americans| Older women and breast cancer| Younger women| Pregnant women and breast cancer| BRCA|

Copyright statement
The contents of this web page are protected. Legal action may follow for reproduction of materials without permission.