Maurice: For Bio-Tech stocks working on cancer cures look at this article
WASHINGTON, Nov 6 (Reuters) - Advances in molecular biology
have allowed drug companies to take dramatic new approaches to
treating cancer, the journal Science reported Thursday.
Most cancer treatments today involve blunt-instrument
approaches such as surgery or the use of poisonous chemicals or
radiation that can kill healthy cells.
New understanding of the basic cellular processes involved
in cancer have encouraged the development of drugs that block
cancer at various stages of its development and that should be
much gentler on the patient.
Scientists also understand that genetic mutations are a
basic cause of nearly all cancers and are finding ways to
counter their effects.
They are all still at experimental stages, but some of the
new approaches being taken by drug companies include antibodies
that block the effects of proteins that start the uncontrolled
cell replication that marks cancer, molecules that block the
chemical doorways, or receptors, used by enzymes and genetic
approaches aimed at restoring normal gene activity.
-- Cell Pathways Inc's FGN-1 brings on apoptosis, the
natural cell 'suicide' process that removes damaged and
potentially cancerous cells.
-- Tyrosine kinase inhibitors, which block tumor growth by
stopping the development of blood vessels that feed them, are
being developed by Sugen , Zeneca , Oncogene
Science and Pfizer .
-- Janssen, a unit of Johnson & Johnson , is working
on a farnesyl transferase inhibitor it hopes will prevent
activity by ras, believed to be the second-most-common gene
involved in cancer. It tells cells whether to divide.
-- Hoechst Marion Roussel, a subsidiary of Germany's
Hoechst , is pursuing CDK (cyclin-dependent kinase)
inhibitors, which should block the out-of-control growth cycle
of cancer cells.
-- Genentech is developing an antibody that blocks
the HER2 growth receptor, which is overexpressed in breast
cancer patients, while rival ImClone Systems is
working on one that blocks the EGF (epidermal growth factor)
receptor.
There are also several genetic approaches.
-- Seattle's targeted Genetics is trying out gene therapy
to replace faulty HER2 genes.
-- Introgen Therapeutics , working with
Rhone-Poulenc division RPR Gencell, and rival
Schering-Plough subsidiary Canji Inc., have engineered
cold viruses to carry the p53 tumor suppressor gene to cells
that have lost it. The p53 gene is involved in up to half of
all cancers.
-- Onyx Pharmaceuticals is taking the opposite
approach, with a modified virus that kills cells that lack p53.
-- Antisense therapy, which blocks the effects of genes
involved in cancer by interfering with protein production, is
also showing promise. Biotech company Genta Inc. is developing
BCL-2 antisense to restore apoptosis |
