GERN NEWS...Pat's article...nothing new
XTENSION OF HUMAN CELL LIFE-SPAN REPORTED IN SCIENCE;
TELOMERASE REWINDS THE CLOCK OF CELL AGING
Science; Telomerase Rewinds the Clock of Cell Aging Business Editors/Medical Writers
MENLO PARK, Calif.--(BW HealthWire)--Jan. 13, 1998--Geron Corporation (NASDAQ:GERN)
and the University of Texas Southwestern Medical Center at Dallas reported today the successful
extension of the life-span of normal human cells using the enzyme telomerase. In a paper published in
the journal Science, January 16, 1998, scientists explain that the introduction of an active telomerase
gene into normal mortal cells resulted in the lengthening of telomeres and a marked increase in the
life-span of the cells, making the cells potentially immortal.
"This paper is a monumental advance in the understanding of the molecular genetics of aging," remarked
Leonard Hayflick, Ph.D., professor of anatomy at the University of California, San Francisco, School
of Medicine and the discoverer of human cellular aging. "The telomerase gene will likely have many
important applications in the future of medicine and cell engineering." Telomerase is an "immortalizing"
enzyme that imparts replicative immortality when expressed in reproductive and cancer cells.
Conversely, cells that do not express the enzyme are mortal. The gene for the telomerase protein was
recently isolated by Geron and collaborators at the University of Colorado at Boulder.
Previous research by Geron and its collaborators has shown that the aging of mortal cells appears to be
controlled by a molecular clock consisting of telomeres -- a chain of repeated DNA segments found at
the ends of the chromosomes. Each time a mortal cell divides, a small segment of telomeric DNA is
lost, and in the absence of telomerase, the shortened telomeres signal the cell to become senescent and
stop dividing. Cells that have no replicative limit, such as reproductive cells, express telomerase, which
synthesizes telomeres, allowing replicative immortality. Telomeres can therefore be envisioned as
"molecular clocks" that limit the life-span of cells, and telomerase can be envisioned as the "key" that
"rewinds" the telomere clocks. In the report today in Science, researchers at Geron Corporation and
the University of Texas Southwestern Medical Center at Dallas collaborated to test the effects of the
immortalizing gene. "We couldn't be more excited about the results," stated Woodring E. Wright, M.D.,
Ph.D., professor in the Department of Cell Biology and Neuroscience at the University of Texas
Southwestern Medical Center at Dallas and one of the senior authors of the paper. "I think this finally
nails down the fundamental cause of cell aging, and provides a direct means of altering the clock of cell
aging for therapeutic effect."
Geron is exploring applications of the telomerase gene to extend the life-span of many different types of
human cells, including skin cells, blood vessel endothelial cells, retinal cells, immune cells, and others.
"We believe that the extension and perhaps immortalization of human cells will have many important
applications for the treatment of age-related diseases," remarked Calvin B. Harley, Ph.D. chief
scientific officer at Geron. In addition to its role in aging, telomerase has previously been shown to be
abnormally active in all types of cancer examined and not expressed in most normal tissues. Telomerase
is therefore thought to be unique among anti-cancer targets because it is universal across cancers and
highly specific to cancer cells. Because telomerase is required for cancer cells to proliferate indefinitely,
Geron is seeking to discover compounds designed to inhibit telomerase. Such drugs are expected to
lead to the death of the cancer cells through resumed telomere shortening, with little to no effect
expected on normal body cells and tissues.
Significantly, the expression of telomerase in normal mortal cells extends their life-span without
transforming them into malignant cancer cells, demonstrating that telomerase makes tumor cells
immortal, but that other genetic alterations are responsible for the malignant characteristics of cancer
cells. "This is the best of all outcomes from our perspective" said Ronald Eastman, Geron's chief
executive officer. "These results suggest that we have a gene that is both an important target for cancer
and for the treatment of age-related disease." Senior authors of the Science article, "Extension of
Life-Span by Introduction of Telomerase into Normal Human Cells" are Dr. Woodring E. Wright from
University of Texas Southwestern Medical Center at Dallas and Dr. Serge Lichtsteiner of Geron
Corporation. Co-authors from Dr. Wright's group include Drs. Shawn E. Holt, Michel Ouellette, and
Jerry W. Shay. Co-authors from Geron are Drs. Andrea G. Bodnar, Choy-Pik Chiu, Maria Frolkis,
Calvin B. Harley, and Gregg B. Morin.
Geron Corporation is a biopharmaceutical company focused on discovering and developing therapeutic
and diagnostic products to treat cancer and other age-related diseases based upon the company's
understanding of telomeres and telomerase, fundamental biological mechanisms underlying aging and
cancer. Note to Editors: Photos and illustrations are available upon request.
Editors who wish to receive a copy of this paper should contact Science News and Information at
202/326-6440 To receive an index and copies of recent releases, call Geron's News-On-Demand toll
free fax service, 1-800/782-3279.
The company desires to take advantage of the "safe harbor" provisions of the Private Securities
Litigation Reform Act of 1995. Specifically, the company wishes to alert readers the matters discussed
in this press release may constitute certain forward-looking statements that are dependent on certain
risks and uncertainties. Actual results may differ materially from the results anticipated in these
forward-looking statements. Additional information on potential factors that could affect the company's
results are included in the company's Quarterly Report on Form 10-Q for the quarter ended
September 30, 1997.
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