Cancer may hold the secret to immortality?

Friends who have watched "The Emperor of All Maladies", what do you think after watching it? Do you have this feeling that the reason why cancer is incurable is because it has evolved more perfectly than humans?

As a PhD in biology, my research area is longevity, but I also study cancer. We found that longevity and cancer have a lot of overlap, so it can be assumed that longevity and cancer have something in common in some aspects (unpublished data). Today, let's talk about the overlap between cancer and longevity.

01. Why do people age?

We know that as we age, our cells become senescent. Reasons include:

1. Accumulation of gene mutations

2. Accumulation of cell damage

3. Accumulation of metabolic waste

4. Telomere shortening

In fact, to put it simply, it is like an aging car. Problems will arise in various parts, such as mitochondria, Golgi apparatus, endoplasmic reticulum, and so on.

So, can we eliminate these senescent cells?

02. Can senescent cells be eliminated?

Can senescent cells be removed? Theoretically, yes. Do you remember the Nobel Prizes in 2002 and 2016? One was awarded to programmed cell death (PCD) and the other to autophagy .

Why did Ohsumi Yoshinori win the 2016 Nobel Prize in Physiology or Medicine? What outstanding contributions did he make to cell biology research?

Programmed death

This is the body's main clearance mechanism. Through these two methods, the body will clean up damaged or aging cells to maintain the state of the cells.

In fact, we can indeed see this situation. For example, a large number of cells in our skin die every day, forming layers of dead skin.

However, the reality is cruel. This cell cleaning process is actually more scientifically called "renewal". What is renewal? It is to replace the old with the new.

However, the question is, where do new cells come from? Some people may say that we have stem cells. There are a large number of stem cells in the human body, and they can make up for the lack of our cells, so we will not lose our hair and become bald (hair loss is a disease and must be treated).

Stem Cells

However, the cruel thing is that our stem cells will also age! Yes, as we age, stem cells become less capable, and even lose their stemness or disappear...

So far, we have no reasonable explanation for the theory of stem cell aging; however, this phenomenon objectively exists.

Otherwise, if the elderly have the same stem cells as babies, as long as they don't get sick, living to be a hundred years is a piece of cake, and achieving immortality is not a problem at all, as they can just repair what is broken.

03. Cancer and longevity share

Cancer and longevity share a lot in common. Although we know that stem cells age with age, we have found a special group that we call "healthy longevity". What is special about this group is that they are different from normal aging, really different.

This group is generally over 100 years old. Although we used to think that human aging is gradual, a strange phenomenon was discovered in group research. 100-year-olds are a special group . They generally show a new trend. This group of centenarians shows a phenomenon that many of their indicators are very young. For example, their blood biochemical indicators are similar to those of 70/80-year-olds, and many substances in their bodies are very active.

Let me give you an example. There was an article published in Nature Biotechnology. They used blood cells from different ages to induce stem cells. The results showed that centenarians were obviously special.

The idea of ​​the experimental design is to compare stem cells by testing the exome and methylome after inducing the cells.

For those over 90 years old, the transition is smaller than the transversion, showing an obvious drastic change.

This is the distribution of mutations. Please note the red group, which are people over 90 years old, and they show a downward trend.

04. About Cancer

In fact, the development of cancer is a process of overall cell reprogramming. In this process, we found that many things that should appear in youth or childhood reappear or increase in cancer.

For example, when people have a physical examination, they often have a tumor marker called alpha-fetoprotein (AFP). AFP is a glycoprotein and an indicator of differentiation. Because the fetal liver is not fully developed, it will be highly differentiated. As a result, it will be highly present in the body. As the liver develops fully, this protein synthesis will be very rare.

Alpha-fetoprotein testing process

However, for liver cancer patients, this indicator reappears because the liver cancer tissue begins to restart the synthesis and differentiation process, thereby synthesizing a large amount of alpha-fetoprotein.

According to incomplete statistics: in adults, AFP can be elevated in the serum of about 80% of liver cancer patients. In fact, not only this indicator, but many indicators in cancer will increase, and most of these indicators are related to cell division and differentiation, which means that cancer tissue is growing rapidly. In fact, these indicators are " youth indicators" in another sense.

Another example is the famous telomerase. I believe many people are familiar with it. The 2009 Nobel Prize in Physiology or Medicine was awarded to Elizabeth Blackburn, Carol Greider and Jack Szostak. Their important contribution was the research on telomerase.

Telomeres are also called "life clocks" by scientists. We know that as cells divide, telomeres gradually shorten. When they shorten to a certain extent, cells will start programmed death. When telomeres can no longer shorten, cells cannot continue to divide and die.

Telomerase can repair telomeres and keep cells alive.

However, in normal people, this telomerase is inactive. But in cancer, this enzyme is activated, and about 90% of cancer cells have growing telomeres and a relatively large number of telomerase. Therefore, cancer cells can replicate indefinitely without going to apoptosis.

Therefore, those who want to repair telomeres should first consider carcinogenicity. However, this enzyme is also active in stem cells and is also abundant in the fetus, otherwise the stem cells will die after dividing a few times.

In fact, longevity and cancer share a lot of similarities, which is quite amazing.

We believe that, in theory, those who can achieve longevity have relatively young indicators. Behind this youth are the various proteins related to youth that are at work, and further, the genes that are at work.

For example, some genes with strong clearance ability, some genes with strong resistance to evolutionary pressure, some genes with strong maintenance of stem cells. Even the maintenance of telomeres themselves. Of course, these contents are still under study, but I am still quite confident about this.

05. Why do we study longevity and cancer at the same time?

Longevity is my main topic, so I have written a lot about it. However, the means of studying longevity are very limited because the longevity samples are limited!

I often see people say, "Hey, why is the gender ratio of your sample unbalanced?" I just laugh it off. Do you think longevity is everywhere? There are many more women than men. Some people think that the number of longevity samples is too small. In fact, these people have made some basic mistakes. They have looked at too much population data and always think that there are many longevity people in the population. In fact, the proportion is very small.

Due to the limited sample size, we have to seek other ways to study longevity. That is, to find out how to achieve longevity. In fact, the method is very simple: the secret to longevity is to avoid serious illness . It seems like nonsense, but this sentence is the core concept of studying longevity and health.

If you avoid disease, you will live longer; if you get disease, you may be affected. Of course, further, you need to ask, what is the reason why some people avoid disease, luck? Or strength? This is what needs to be verified.

This statement has been verified in various studies. Most long-lived people, in fact, never get extremely serious diseases, such as cancer, serious cardiovascular disease, etc.; or, they will delay the onset of such diseases. For example, normal people will have a sharp increase in certain senile diseases after the age of 60, such as cardiovascular disease, Alzheimer's disease or type 2 diabetes, etc. However, for those extremely long-lived people, their overall incidence rate will be delayed until 70, 80 or even 90 years old. There is a special term for this in biology, called compression of morbidity, and a large amount of group data in the last century supports this conclusion.

Therefore, most people who study longevity will study various age-related diseases, and study longevity from the perspective of why centenarians do not or rarely get these age-related diseases. It can be considered a roundabout way to save the country. In fact, I also study cardiovascular diseases and Alzheimer's disease.