More and more scientists have made substantial progress in conquering cancer through unremitting efforts. 2017101October 9th
Professor Zhang Kang and his team published the latest scientific research results in the international authoritative academic journal Nature-Materials. Based on large-scale clinical data analysis and deep machine learning, they developed an efficient blood test method, which can be non-invasive.
Rapid and effective diagnosis of primary liver cancer.
Liver cancer is one of the most deadly cancers in the world, and its early diagnosis and treatment are very important. This time, the human dream of overcoming cancer has a clearer outline.
At the Tencent WE conference on10.5, 165438 invited Zhang Kang, a cancer research scientist and director of the Institute of Human Genome Medicine at the University of California, San Diego. Lifelong full professor of ophthalmology and human genetics at the University of California, San Diego, USA, and the first dual-doctor winner of medicine and genetics from the mainland at Harvard University and Massachusetts Institute of Technology.
Zhang (surname)
Kangzai ziran
160 More than 60 important papers were published in top international journals. Based on large-scale clinical data analysis and deep machine learning, his research team has developed an efficient blood test method, which can diagnose quickly and effectively in a non-invasive way.
The research results of diagnosis of primary liver cancer were published in Nature-Materials, a subsidiary of Nature Publishing Group, an international authoritative academic journal, on June 9, 2006.
"Through our experiments, sometimes through some
Gene editing or other ways, we can find that it can really speed up or slow down this clock, so I always hope that in our life, we humans can live 150-200 years, of course.
This may lead to problems in other societies. Should we consider sending some people to Mars or the moon? "Zhang Kang stressed at the end of the speech.
The following is the full text of Zhang Kang 1 1.5 Tencent WE conference speech:
Zhang Kang
Good afternoon, everyone. It's an honor to be here.
I would like to ask you to pay attention to people's health, that is, cancer and aging.
Why are people so afraid of cancer? Because the mortality rate is particularly high. Why is the cancer mortality rate so high? Because it is a malignant tumor, it can metastasize quickly, and the risk of death after metastasis will greatly increase. In addition, it will also lead to organ tissue attenuation, leading to some cachexia, that is, sucking away human nutrition.
There are many reasons for cancer, including genetic reasons, environmental reasons, pollution reasons and diet reasons. However, I want to tell you another important reason. The causes and present situation of cancer are very serious. Every day, 1000 people are diagnosed with cancer, and about 8000 people die of cancer every day. The cost of cancer treatment is about10.5 million yuan, which is the average level.
I
Let's take a look at the top cancers in China. Cancer survival rates in the United States and China are different. One reason is early detection and treatment. Liver cancer, for example, is more likely to occur in China, because it is difficult for liver cancer to be early.
Only 10% patients can be diagnosed early, and there is no effective screening method, especially early. So early diagnosis is very difficult, so the mortality rate is particularly high.
Obviously, if the diagnosis is made earlier, the treatment effect will be better and the curative effect will be better, which is why it is very necessary for us to find biomarkers, which can make us diagnose more accurately and earlier.
I want to introduce you to DNA methylation therapy. This is methylation at the human or cellular level, and it is also related to cancer. DNA methylation is the most basic change of our DNA gene. This is the most basic result of our genetic variation.
basis
Because methylation is very important, when a cell becomes a cancer cell, it must adjust the cells involved in cancer growth, which means that some specific genes in our cells will change. Let's have a look.
In the next picture, there are some dots that are methylated genes. We can also see that some cancers may not have metastasized or invaded the surrounding tissues, and some cancers have metastasized. you can
In order to see that DNA methylation is completely different in these two cases, whether for different stages of cancer or different types of cancer, we can diagnose cancer early by this method.
Next, I will introduce some concepts to you, which are involved in the research we have done. In this study, we found the marker of methylation and diagnosed cancer with the least invasive method. Lung cancer, liver cancer, rectal cancer, breast cancer.
in addition
In addition, we can see which cancers are different from normal tissues and what are the causes of cancer. For example, if a patient has a liver mutation, we will find out what causes cancer. Of course, this
This is not enough. In order to diagnose cancer, we must obtain the diagnosis tissue through surgery. It would be better if we only took a drop of blood to see if the patient had cancer.
This information can be used when the DNA released by tumor cells is released into the blood stream, so that we can make a non-invasive diagnosis and fully understand the situation of tumor tissue, which is real-time dynamic information.
Let me give you an example, using ctDNA to diagnose liver cancer. This is a very large-scale study, and it is also the first time to use 2000 cancer patients as the control group. Through this study, we found that using ctDNA, we can diagnose cancer very accurately, which is different from conventional cirrhosis or other liver diseases.
In addition, we can see that if the patient is undergoing surgery and the tumor is gone after surgery, we can see that the patient's markers have decreased. If the tumor has recovered, we can see that the methylated markers have recovered, which is a real-time response and monitoring of the drug efficacy.
the same
Sometimes we can also judge whether the patient is in the early or late stage of cancer, and it can also have a different effect from the usual blood drawing method. If we go to hospitals in China or the United States, the only thing we use now is alpha-fetoprotein.
White is a sign, but alpha-fetoprotein is very insensitive in early cancer. If there are 100 patients with liver cancer, this method can only diagnose 60 patients at most, and our study
The accuracy of specificity and sensitivity was 99.5%.
In addition, we can also use this marker to predict the recovery of patients after discharge, and what is the probability that patients will continue to live for 5 years 10 years. You can see the blue line in this picture, that is, the patient's survival rate after rehabilitation is higher, and we can do better for him, while the patient in the red line needs to treat his cancer cells more actively.
this
This study shows that we can monitor and track the tumor load in real time. This figure also shows that if the tumor load is high, it means that every effort should be made to solve it. If it is low, it reflects.
Different patients. On the left, the patient's treatment effect is good, and on the right, it seems that the patient's treatment effect is not very good, and the tumor has recovered. These are different examples, reflecting how we use this information.
To solve the problem of cancer recurrence.
This is a comparison of different screening and diagnostic methods. Marker method can let us see something before tumor metastasis, we can monitor it, and it is a non-invasive method, which can let us see very important information, that is, which cancer comes from which tissue and cell.
still
There are many other ways to diagnose cancer. I want to emphasize early diagnosis, because I just said that early diagnosis is a very important factor for us to reduce the incidence of cancer or the cost of cancer treatment. this
Zhang PPT shows that DNA methylation can find about 1 10,000 cancer cells, in other words, the tissue of a tumor is as big as a pea. It is not good to use some traditional imaging methods. if
You go to the hospital for CT or something. This method is impossible or not sensitive enough.
If the traditional method needs to contain 5 million to100000 cells, it is a relatively large lesion sample. Our method has better advantages and can be done without more cells.
this
This slide is very important. The vertical axis is the survival rate, and the horizontal axis is the stage of cancer. You can see that the survival rate on the left is higher, which means that the survival rate of cancer patients in the first or second stage is higher. If you move to the right, the situation will be.
Better, the possibility of survival in five years is relatively low. Imagine that if we adjust the diagnosis of cancer, we can only diagnose three or four stages. If we can diagnose it in one or two stages, we can diagnose it in a very.
Greatly improve the survival rate of patients.
This is a very urgent matter, because when a patient enters the hospital in China, at least 60% of the patients are already patients with advanced cancer, that is to say,
Three or four issues. Not only is the survival rate of these patients very low, but the choice and cost of treatment are also very high, and there are fewer treatment schemes. If it can be diagnosed and treated early, good.
This place is very obvious.
Now we can reduce the tumor mortality rate by half together. We can do this through early diagnosis and treatment. Now many companies in the United States and China have done a lot.
This kind of work is much more. As long as everyone Qi Xin works together and integrates technology, we should be able to achieve this goal. If we have blood tests, such as going to the hospital for routine annual inspection experience, we can do it.
For early diagnosis.
It is also very important that the primary cancer is local and can be removed and cured by surgery. It is impossible to cure cancer unless you can take action in the first stage.
In order to achieve such a goal, we have not only studied liver cancer, but also studied many leukemia patients. We want to study 500,000 samples stored in our refrigerator through methods such as machine learning, so as to build a very huge database, and then develop a marker to identify various types of cancer.
receive
Next, I want to change the topic and introduce another topic, which is also related to the above, that is, the problem of aging. After we solve the problem of cancer, the next problem is aging, because this is who we are.
Another problem we face. Have you ever wondered why we get old? When we are born, we are actually doomed to die. Why can we only get older and younger in the end?
How do we stay young?
It is necessary for us to study aging, because aging is the first risk factor of cancer, cardiovascular disease and diabetes. Many patients are over 65 years old, and 92% of them suffer from chronic diseases. Besides, our population is getting older and older. There are many signs that can help us understand what is our aging biological clock.
In addition, there are many applications, such as predicting some diseases and diagnosing diseases. In addition, there are some markers and immune markers.
I want to tell you a new marker, which is the marker of DNA methylation.
big
Think again, go back to methylation I talked about before. Methylation is like a switch, which is the switch of many functions in our body. Why do you think that the heart and liver, hands and arms are not the same as aging, and they are all controlled by genes?
Different genes are in different tissues of your body, and genes in different places are controlled by methylation, so you can control your tissues by controlling methylation.
Through our research
(genomic methylation research), we can look at some important methylation markers, and as a result, we find that this methylation marker exists in all cell tissues and persists, whether it is
Blood cells, or in our brains, are everywhere, just like our cells know that we are getting older, just like a clock, which makes us get older and older in the process of continuous ticking.
Some people are younger than their actual age, while others are older than their actual age, which is actually controlled by lifestyle and disease. For example, diabetes is an important driver of aging now, as well as mental conditions, such as stress.
in addition
In addition, there are differences between men and women. For example, women are often five years younger than men, and cancer cells in the body are always older than the surrounding tissues. The clock has been used in 65,438+00 studies.
Sample 20 thousand. In other words, this clock runs in all cells and tissues of all people. Of course, this clock is different from the clock mentioned by this year's Nobel Prize winner. Does his clock tell us whether it is day or night?
In fact, our methylation clock is pushing us from the young to the old.
As I told you before, there are many factors that will affect our biological clock. Genes are obviously a factor, followed by diet, mental stress and exercise. Besides, people want to know whether we can solve our aging problem by taking drugs.
In our laboratory, we found that we can control our methylation clock, which can be controlled by animal models and cell culture. We can speed up or slow down this clock.
compare
For example, a 90-year-old cell, with some stem cells, becomes functional stem cells, just like embryonic stem cells. Then we measure this clock, and we can set it to zero. On the other hand,
If you experiment with some younger cells, which are extracted from people who died before the age of 20, and then you measure the methylation clock, this clock is always 60-200 years old, because this clock.
Is one of the reasons that make us old.
Through our experiments, sometimes by editing some genes or other ways, we can find that this clock can really speed up or slow down, so I always hope that in our lifetime, we humans can live 150-200 years. Of course, this may lead to other social problems. Should we consider sending some people to Mars or the moon?
most
After that, let me sum up. I just want to tell you today that methylation is a very important mechanism in the human body, which is related to our cancer and aging. We can use methylation markers for early screening and diagnosis of cancer.
I hope this can greatly reduce the death rate caused by cancer. This methylated biological clock is also very important in the aging process. We hope to predict aging through this and treat it.
question
Our goal is to hope that we can work together to reduce the death rate caused by cancer by half by 2027 by using new technologies and using methylated markers.
Early treatment, I hope our life expectancy will be extended to 150-200 years. In this way, I would like to take this opportunity to thank Tencent and the previous and current laboratories for their achievements.
Member, also my partner, thank you!
That's impossible.