Friday, December 23, 2011
Remember Geron? Here is the latest news I've seen on the biotech company.
Monday, December 12, 2011
The Immortal Life of Henrietta Lacks
HeLa's contributions to the Nobel Prize
3 Americans Share Nobel for Medicine
From left, Jack Szostak, Carol Greider and Elizabeth Blackburn.
The Nobel Prize in Physiology or Medicine was awarded Monday to three American scientists who solved a problem of cell biology with deep relevance to cancer and aging. The three will receive equal shares of a prize worth around $1.4 million.
The recipients solved a longstanding puzzle involving the ends of chromosomes, the giant molecules of DNA that embody the genetic information. These ends, calledtelomeres, get shorter each time a cell divides and so serve as a kind of clock that counts off the cell’s allotted span of life.
The three winners are Elizabeth H. Blackburn of theUniversity of California, San Francisco; Carol W. Greider of the Johns Hopkins University School of Medicine; and Jack W. Szostak of Massachusetts General Hospital.
The discoveries were made some 20 years ago in pursuit of a purely scientific problem that seemingly had no practical relevance. But telomeres have turned out to play a role in two medical areas of vast importance, those of aging and cancer, because of their role in limiting the number of times a cell can divide.
“I am thrilled that the basic science can be celebrated,” Dr. Greider said in an interview Monday.
Only eight women had won the Nobel Prize in Physiology or Medicine. Asked how she felt about becoming No. 9, Dr. Blackburn replied, “Very excited, and hoping that nine will quickly become a larger number.”
Thomas Cech, a Nobel Prize winner at the University of Colorado, said the discovery had had a broad impact on several fields of biology and medicine and had also provided a “fascinating insight” into the transition between the DNA world and the RNA world that preceded it in the origin of life. RNA is a close chemical cousin of DNA.
Though Americans have again made a clean sweep of the Nobel medicine prize, two of the three winners are immigrants. Dr. Blackburn was born in Tasmania, Australia, and has dual citizenship; Dr. Szostak was born in London. Dr. Blackburn came to the United States in the 1970s because it was “notably attractive” as a place to do science. While America is still a magnet for foreign scientists, she said, “one shouldn’t take that for granted.”
Dr. Szostak also said the world was now more competitive in science. “So maybe we have to work a little harder to attract people from around the world and make sure they stay here,” he said.
Dr. Cech, former president of the Howard Hughes Medical Institute, said the more onerous visa requirements imposed on foreign scientists in the wake of the Sept. 11 attacks were benefiting European countries especially. “Even now, there is an implication when foreign scientists apply for visas that they should be distrusted, denied several times, and should have to hire lawyers and jump through a lot of hoops,” he said.
All three of the prize winners seem to have had science in their genes, and certainly in their home environment. Dr. Greider is the daughter of two scientists with doctorates from the University of California, Berkeley, and she, too, has a Ph.D. from there. Dr. Szostak’s father was an engineer. Both of Dr. Blackburn’s parents were physicians.
The study of telomeres is notable as a field of research in which female scientists are particularly prominent. Dr. Greider said she ascribed this to a “founder effect,” the founder being Joseph Gall of Yale University. Dr. Gall trained Dr. Blackburn and other women, and they recruited others to the field “because there is a slight tendency for women to work with other women,” Dr. Greider said. She herself trained with Dr. Blackburn.
The field of telomere research grew out of a puzzle in the mechanics of copying DNA. The copying enzyme works in such a way that one of the two strands of the double helix is left a little shorter after each division. Work by the three winners and others led to the discovery of telomerase, a special enzyme that can prevent the shortening by adding extra pieces of DNA.
Dr. Blackburn addressed this problem by working with a single-cell organism found in pond water known as Tetrahymena. She found in 1978 that the telomeres had a very unusual structure, in which the same sequence of six DNA units was repeated some 50 times.
She and Dr. Szostak, who with her help had detected telomeres in yeast, then proposed that cells must possess a special enzyme that added these repeat units to the end of chromosomes so as to compensate for the incomplete job done by the copying enzyme.
Working in Dr. Blackburn’s lab as a graduate student, Dr. Greider tracked down this enzyme, now known as telomerase, in a central experiment that finished on Christmas Day, 1984. Going into the lab that morning, Dr. Greider saw from the telltale signature of the six-unit repeat that she had captured telomerase. “That was a really exciting day,” she said.
Later she found that telomerase contains a special piece of RNA that it uses as a template to elongate the chromosome with the six-unit repeats. The unexpected involvement of RNA reflects a time early in the origin of life when all the important chores in the cell were performed by RNA, not DNA.
This piece of basic biology soon turned out to have important implications for aging and cancer. Telomerase is usually active only at the beginning of life; thereafter the telomeres get shorter each time a cell divides. If they get too short, a cell is thrown into senescence, meaning that it cannot divide again.
Short telomeres are known to have a role in certain diseases of aging, like aplastic anemia. Telomeres are also important in cancer, a disease in which control of cell proliferation is lost. Cancer cells need to reactivate the telomerase gene, or their telomeres will get steadily shorter, forcing them into senescence. In some 80 to 90 percent of human cancer cells, the telomerase gene has been switched back on, Dr. Blackburn said. The Geron Corporation has two clinical trials under way, one of a drug and one of a vaccine, to see whether cancers can be treated by inhibiting telomerase.
Both Dr. Blackburn and Dr. Greider still work on telomerase, but Dr. Szostak left the field 20 years ago to explore a much broader question: how life could have originated from the simple chemicals present on the early earth. He has already made advances in this long intractable field, notably by showing how a proto-cell could have formed and then imported the RNA building blocks. Dr. Szostak hopes next to show how the proto-cell and its RNA could divide naturally into two daughter cells, a feat that, if achieved, could well be a candidate for a second Nobel Prize.
Right to Privacy
HIPPA and HeLa
Friday, December 9, 2011
The BEST part of the book
My favorite part of the book was when the family, Henrietta’s family, went and visited her in the lab (technically they visited her cells, HeLa cells). When the family was in the lab and Deborah spoke to a vial of cell and said “You’re famous, just nobody knows it.” This brought up so much emotion when I read this and I felt almost as if I was in her situation. LOVE this part, this was my favorite part
Lacks Family
A Must For Scientist
The Immortal Life of Henrietta Lacks -- a noteworthy subject.
So another noteworthy matter I stumbled upon as I read The Immortal Life of Henrietta Lacks was that African American people were referred to as the “syphilis soaked race”. I don’t think people of any race or color should be referred to as a “syphilis soaked race”. I would not like to be referred to as this and I know nobody else would like to either. Again this is just another thing I found significant enough to make a note of.
The immortal life of Henrietta Lacks
The immortal life of Henrietta Lacks
So as I read the book I jotted little notes to myself. These little notes were mostly about things I found attention grabbing and noteworthy. One of the first things I took note of was the fact that the doctors at Johns Hopkins thought it was ok to take samples of patients and/or experiment on patients without their knowledge. I believe their reasoning was that they had a right to do so because they were not indebted to the hospital. This was a form of payment to the doctors I believe. The doctors benefitted from the patients just as the patients benefitted from the doctors. This kind of reasoning is erroneous in my mind. Now I do not want to get political or anything but I think this kind of stuff (medical treatment) should be free and if any doctor is going to experiment of me or take samples of me, I would definitely like to know. I know this kind of thinking doesn’t exist anymore (or at least I think it doesn’t anymore) but this just shows how much things have changed, at least in this perspective.
Elsie Lacks
I can see in 3-D (first 3-D tissue created: 2010)
http://www.sciencedaily.com/releases/2010/05/100526170248.htm
Thursday, December 8, 2011
Top-grade stem cells seen boosting research trials
LONDON (Reuters) - British scientists have made the first human embryonic stem cells of a high enough grade to use in patients and deposited them in a public stem cell bank for development in human trials by drug companies and researchers by 2014.
A team from King's College London said on Monday they were submitting two clinical-grade stem cell lines to the UK Stem Cell Bank (UKSBC), which will test and validate them before offering them to researchers.
This could speed the path towards new stem-cell treatments for conditions like blindness, severe injury or heart disease.
"This first batch of cells is the culmination of nearly 10 years of research. This is a significant milestone," said Peter Braude, who led the King's team.
The cells are the first to be grown completely free from animal-derived products, known as "xeno-free," and developed specifically to be of clinical grade and for public use.
The hope is that the cells will be grown and processed by the bank to feed cell stocks for human trials and, beyond that, patient treatments.
The cells have the potential to become the "gold standard" lines for developing new stem cell based therapies for use in regenerative medicine trials in patients, Braude told reporters at a briefing.
It is likely to be many years before treatments are fully developed and licensed, but the cells could be used in human trials of potential therapies by 2014, the team said.
Stem cells are the body's master cells, the source for all other cells. Scientists say they could transform medicine, providing treatments for blindness, spinal cord and other severe injuries, as well as generating cells for damaged organs.
Human embryonic stem (hES) cells can be grown in the laboratory indefinitely while retaining their capacity to develop into specialized cell types, such as nerve or heart muscle cells, which can then be used in clinical trials.
The UK Stem Cell bank already has more than 90 research grade stem cell lines for use in laboratory studies, but as yet has no clinical grade xeno-free lines for use in human trials.
"In the future, patients hoping for the benefit of regenerative medicine for serious medical conditions caused by illness, injury and ageing can expect improved progress on cures or amelioration from hES cell-based therapy," said Dusko Ilic, a senior lecturer in stem cell science at King's.
A few companies, such as Pfizer and Advanced Cell Technology, are already conducting or are about to start human trials using hES cells -- which are harvested from embryos -- to test their potential for repairing spinal cord injuries and eye disorders like macular degeneration.
But the hES cell lines for these early trials were reclassified from "research grade" to "clinical grade" for specific short-term clinical studies in selected disease areas.
Braude said this is not considered appropriate for the future of cell therapy because of the expense of extra testing and reclassification, and the potential risks.
"While it might be reasonable to incur additional risks for these early pioneering studies, it is not reasonable to accept these risks for the long-term future," he said. "Therefore the highest standard of xeno-free lines are urgently needed."
Braude's team's cells were grown from frozen embryos donated by patients who had had in-vitro fertilization (IVF) treatment and no longer wanted to use their remaining stored embryos. The embryos would otherwise have been discarded, Braude said.
Glyn Stacey, head of the UKSCB, said these first clinical grade lines would be an "important resource" and an initial step towards the bank's aim to make available a panel of tested clinical grade lines within the next three years.
"The process of testing will be rigorous and not all cells lines received will make the grade," he said.
(Editing by David Cowell)