[MOL] Internet Home - American Association for Cancer Research (AACR)

[Martin Auslander <fitecancer@earthlink.net>]

Good Day My FRiends

Thought this might be of some interest.



file:///C|/windows/temp/nscomm40/tmp/tmp4/edt1.htm

God Bless You,
marty auslander

Title: Internet Home - American Association for Cancer Research (AACR)

NEW DELIVERY
SYSTEM FOR TUMOR-SUPPRESSOR GENE P53 HOLDS
           PROMISE
FOR PROSTATE CANCER TREATMENT

 Research results presented at International Conference sponsored jointly by AACR,
                            NCI and EORTC

 Washington, DC … November 18, 1999 --- Researchers announced today that they
 developed a new system to deliver the tumor-suppressor gene p53 directly into the tumor
 through the bloodstream, which, when used in combination with radiotherapy and
 chemotherapy, may significantly improve treatment outcomes for prostate cancer patients.
 Results were presented today at the International Conference on Molecular Cancer
 Therapeutics - Discovery, Development and Clinical Validation sponsored by the
 American Association for Cancer Research (AACR), the National Cancer Institute
 (NCI), and the European Organization for Research and Treatment of Cancer (EORTC).

 "Our data demonstrate that by introducing p53 in this new way, we can sensitize prostate
 tumors to radiation and chemotherapeutic agents. Also, by delivering the p53 gene
 directly into the bloodstream, we can increase the number of cancer cells that are targeted
 and reached - the cells of the actual tumor and those that may be roaming throughout the
 body," says Kathleen F. Pirollo, Ph.D., research associate professor at the Lombardi
 Cancer Center at Georgetown University in Washington, DC.

 Abnormalities in p53 have been found in the majority of human cancers. This gene is
 influential in causing programmed cell death, called apoptosis, and has been the focus of
 several studies attempting to introduce "normal" copies of this gene into cancer cells in
 order to stop the disease. The most common way of introducing the normal p53 gene into
 cancer cells has been to carry it through a modified common cold virus, the adenovirus.
 However, limitations to this method have occurred in terms of the number of cells
 reached, the ability to target only the cancer cells, and possible adverse effects.

 The new delivery system uses a combination of three compounds -- ligands, p53 and
 liposomes -- in a carefully developed ratio to produce a small enough structure to
 penetrate into the small blood vessels in the tumor. Ligands are molecules that recognize
 and attach to specific protein sequences or receptors on the surface of cells with high
 specificity, meaning that they recognize and attach only to tumor cells. Tumor cells have
 many more of these than most normal cells. Folic acid or transferrin (the protein that
 carries iron in the bloodstream) are used as the ligands since they are highly recognized
 by tumors and can attach easily to tumor cells. Liposomes are fatty particles that enclose
 and protect the p53 gene DNA. The p53 gene is enclosed in the liposome, which in turn
 is attached to the ligand, and the combined entity is released into the blood to find its way
 to the cancer cells. When the normal p53 is reintroduced into the cancer cells, these cells
 become more sensitive to common chemotherapy drug and radiation therapy, thus killing
 more of the tumor.

 The AACR is the oldest and largest scientific organization in the world focused on the
 multidisciplinary aspects of basic, clinical, and translational cancer research for the
 prevention and cure of cancer. Its 15,000 members come from 80 countries. The NCI is
 part of the National Institutes of Health. The EORTC is an international research
 organization whose goal is to facilitate the transition from experimental discovery into
 state-of-the-art treatment of cancer. The NCI-EORTC Symposium on New Drugs in
 Cancer Therapy has been held biennially in Amsterdam for two decades. Under the
 auspices of these three prestigious organizations, it will now occur annually to help
 researchers keep up with the rapid pace of discovery in molecular biology and genetics
 that is identifying new targets for cancer therapeutics.

                                 ###

 "Ligand-targeted, liposome-mediate p53 gene therapy in combination with
 radiation or chemotherapy leads to prostate tumor regression" (abstract #508)
 Kathleen F. Pirollo, Ph.D., Lombardi Cancer Center/Georgetown University
 Poster Session 5, Section 2, Board 16 - Exhibit Hall
 Thursday, November 18 -- 12:15 pm - 2:15 pm