The most dangerous cancer cells are actually the ones that are more like stem cells, which have this ability to produce themselves over and over again. More and more cancer biologists say stem-cell-like cells in cancers are the most dangerous.
— Elizabeth Blackburn
One characteristic aspect of ageing is the increased susceptibility to disease, particularly age-related diseases such as cardiovascular diseases and cancer.
In humans, the thing is that as we mature, our telomeres slowly wear down. So the question has always been: 'Did that matter?' Well, more and more, it seems like it matters.
In 2004, results from a study that I worked on with colleagues at the University of California, San Francisco, linked chronic stress to shortening of telomeres.
If we think of our chromosomes - they carry our genetic material - as being like shoelaces, I work on the plastic tips at the end that protect them.
Basically, when you look at different types of cells, such as fibroblasts, which form connective tissue, or epithelial cells, from saliva, you see general correlations within a person. If telomeres are up for one cell type, they're up for others overall.
I'm pretty good about getting some exercise every day - well, most days. The secret for me was to put the elliptical in front of the TV.
At Cambridge, there was a completely unintimidating culture, and there were no class divisions among the students.
Being senior enough in the field, having enough solidity, I don't feel afraid of being marginalized.
The conservative statement is that telomere length is a biomarker, but it's probably not passive. There are some very intimate relationships between things such as molecular markers for inflammation and telomere health.
In the 1970s, I did a Ph.D. with Fred Sanger in Cambridge who was in the process of inventing ways to map what's inside DNA. He later won the Nobel Prize.
Telomeres are the protective caps at the ends of chromosomes in cells. Chromosomes carry the genetic information. Telomeres are buffers. They are like the tips of shoelaces. If you lose the tips, the ends start fraying.
What is it that keeps you so interested in the telomere? It's so intricate and complicated, and you want to know how it works.
In my early work, our molecular views of telomeres were first focused on the DNA.
Tracing the beginnings of the interwoven stories of science can be arbitrary, as beginnings are so often lost in the mists of time.
I spent my first 4 years living in the tiny town of Snug, by the sea near Hobart. Curious about animals, I would pick up ants in our backyard and jellyfish on the beach.
When you bring telomerase RNA levels down by using a mechanism that targets the RNA for destruction, the cells which were running on very high telomerase levels are now running on a lean diet of telomerase.
Ageing is so many different things, and cells being able to self-renew is part of the picture but not all of it.
The goal is to learn more about telomere length and other markers of ageing, how best to measure these markers, how they are related to health and lifestyle, and how people respond to learning their own telomere length results.
Checking your telomere length is a bit like weighing yourself: you get this single number which depends on a lot of factors. Telomere length gives a sense of your underlying health.
We're collecting about 100,000 telomere lengths in saliva samples and then looking at how those relate to both the extensive longitudinal clinical records that Kaiser is collecting and the genome sequence variations.
We think there are lifestyle factors that boost telomerase naturally.
Exercise mitigates the effects of stress - and stress, we know, shortens telomeres. In fact, early studies indicate that stress reduction techniques like meditation help people maintain the length of their telomeres.
I decided I wanted to go to Cambridge, and then I got introduced to Fred Sanger. I was very conscientious, and I asked him when I first got there if I should start reading up on things. But he said, 'No, I think you can just start these experiments,' so I plunged right in.
When scientists get old, they get interested in the brain, and I'm a little bit afraid I'm falling into that.
Medicine has been successful by treating diseases in a very specific way once the damage is done. But telomere length integrates a lot of factors together and gives you an overall picture of risk for what is now emerging as a lot of diseases that tend to occur together, such as diabetes and heart disease.
Researchers have found that the brain definitely sends nerves directly to organs of the immune system and not just to the heart and the lower gut. In that way, too, the brain is influencing the body.
I've only actively promoted what we always hope is good science.
I was using very unconventional methods to sequence the telemetric DNA, originally.
As maize became important for human food worldwide, modern agricultural research on maize breeding continued the corn breeding begun thousands of years ago in the Central American highlands.
I chose biochemistry as my major and graduated after 4 years with an Honours degree in Biochemistry. During that time, I had come to love biochemistry research, although I was just getting my feet wet in laboratory research.
I was born in the small city of Hobart in Tasmania, Australia, in 1948. My parents were family physicians. My grandfather and great grandfather on my mother's side were geologists.
Cancer cells have a lot of other things that are really wrong with them, and we should never forget that these are cells that have become deaf to all the signals that the body sends out, such as you can multiply a certain amount, you can be in a certain place in the body, where to stay, where to move, and so on.
Cancer cells have had so many other things go wrong with them, genetic, non-genetic changes, that those cells, one of the things they then get selected for is that they have lots of telomerase because now the telomeres in those cells get maintained.
If a test showed you had telomere shortening, it would be a red flag suggesting you should take a look at possible risk factors.
Observational studies show that exercise, nutritional supplements and reducing psychological stress can help. Chronic high stress and smoking can lead to accelerated telomere shortening.
We're involved in a very large study that's federally funded and being done with Kaiser Permanente, and saliva is a very non-invasive way to get cells from the body.
This enzyme, called telomerase, slows the rate at which telomeres degrade, and research indicates that healthy people with longer telomeres have less risk of developing the common illnesses of aging - like heart disease, diabetes, and cancer, which are three big killers today.
Studying organisms at a molecular level was totally compelling because it was moving from being a naturalist, which was the 19th-century kind of science, to being very focused and really getting to the heart of these molecules.
No one ever said, 'Be a doctor.' But because so many members of my extended family - aunts, uncles - were doctors, there was this expectation that I'd probably be a physician.
Challenges in medicine are moving from 'Treat the symptoms after the house is on fire' to 'Can we preserve the house intact?'
We and other groups are seeing clear statistical links between telomere shortness and risk for a variety of diseases that are becoming very common, such as cardiovascular disease, diabetes and certain cancers.
In my lab, we're finding that psychological stress actually ages cells, which can be seen when you measure the wearing down of the tips of the chromosomes, those telomeres.
Generally, we try to have a situation where the person is healthy, so you're not confounded by disease. So, that means that healthy individuals are donating their blood samples for the studies.
Biology sometimes reveals its fundamental principles through what may seem at first to be arcane and bizarre.
For me, arguably the story of telomeres and telomerase began thousands of years ago, in the cornfields of the Maya highlands of Central America.
Perhaps arising from a fascination with animals, biology seemed the most interesting of sciences to me as a child.
