Hello to all those who are recovering, those who have recovered, and everyone who simply cares about their health!
The reason for my today's post about a blood test for the presence of gene mutations BRCA1 and BRCA2 have been actively discussed in one of the social networks photos of a successful young woman. I won’t name her, both for confidentiality reasons and simply because it’s not important in principle. Just recently she posted a photo with an emphasis on her big breasts. Among the commentators of this photo, a controversy broke out over the naturalness of the breasts. But the owner of that same breast said that she does not hide at all the fact that she has implants. At the same time, she wrote that one of the reasons why she decided to have breast implants was, according to her, breast cancer prevention, just like I did.
And one of the commentators attacked her with sharp criticism:
“Are you serious about Angelina Jolie? What now, if there is breast cancer in the family, you have to get rid of part of your body and get an implant?! Cancer prevention in any form has never saved anyone from cancer! It's not as simple as it seems. Cancer is deep processes in consciousness on a subtle level and only then on physical level.”, this woman wrote.
Honestly, I was horrified that people make such serious statements without studying this issue one bit. It is because of such beliefs that, in many cases where cancer can be prevented, in our country, and throughout the world, people die from oncology, which has long been successfully treated.
And I decided to write this article for all the skeptics about any surgical decisions in the breast area :) Modern medicine does not stand still, it develops. It has long been discovered that mutations in the BRCA1 and BRCA2 genes can lead to breast cancer or ovarian cancer.
To begin with, two very important points:
- Before deciding to have surgery, Angelina Jolie underwent a blood test to check for gene mutations BRCA1 and BRCA2. And she was found to have such a BRCA1 gene mutation that the risk of developing breast cancer was 87%, and the risk of ovarian cancer was 50%. Only after this did she decide to have surgery.
- No amount of work at the “subtle level” can change gene mutation. Gene mutation cannot be treated. I don’t know, maybe in the future medicine will be able to treat such mutations. Please do not believe anyone who now offers you to “treat” your genes. These are scammers.
Prophylactic mastectomy- this is one of the effective forms reducing the risk of breast cancer by up to 5-10%, and prophylactic oophorectomy, that is, removal of the ovaries, reduces the risk of cancer by 90%.
It's not easy to make a decision about something like this preventive measures. After all female breast is a symbol of femininity and motherhood. But give yourself time. Don't say no right away. Consult in several places. Work with your fears. You may need psychological support.
When I found out about my diagnosis and was undergoing treatment, not a single doctor told me about the possibility of taking a test for gene mutation. Although I was diagnosed with an aggressive form of cancer: triple negative. I don’t know how things are now in oncology clinics; do doctors give enough information to their patients? Consult your doctor about the need for such a test. I hope this post will help you do right choice regarding treatment.
In what cases is it recommended to undergo a blood test for the presence of mutations in the BRCA1 and BRCA2 genes?
- Firstly, those who have been diagnosed with triple negative breast cancer;
- If you were diagnosed with breast cancer before age 40;
- If you are healthy but have a family history of breast or ovarian cancer.
Typically, studies for the presence of mutations in the BRCA1 and BRCA2 genes take no more than 1 month.
What to do if a mutation of the BRCA1 and BRCA2 genes is detected?
If you, like me, have been diagnosed with a mutation of the BRCA1 and BRCA2 genes, then you should first of all consult with a geneticist, then with your oncologist and choose an action plan depending on the degree of risk, your age, and future plans for having children etc.
It can be:
- regular breast self-examination;
- dynamic observation ( regular visit mammologist, ultrasound and mammography, etc.);
- taking tamoxifen (an expensive drug with a lot of side effects);
- prophylactic oophorectomy;
- prophylactic mastectomy followed by reconstruction;
- something else depending on the degree of development of medicine in your region.
What's the good news for BRCA1 and BRCA2 gene mutation carriers?
- According to statistics, the survival rate of patients with hereditary cancer of the female reproductive system is significantly higher compared to the general group of patients;
- Even if a mutation is detected in you, this does not mean at all that the process will ever be started in your body, 70-90% is not yet 100%. You always have the remaining 10-30%.
- You can develop high stress tolerance, work with your fears, or just pray higher power about giving you health. The choice is yours. 🙂 No one can force you to have a mastectomy.
Where can I get a mutation test?
I know that with a purpose early detection breast, ovarian and cancer prostate gland Moscow City Health Department and Moscow Clinical science Center them. S.A. Loginova DZM every Saturday from July 7 to September 22, 2018(from 8.00 to 14.00) carries out a screening program (completely FREE).
To take the analysis, you must have your passport with you and give consent to the processing of personal data (provide a reliable method of feedback).
- Preliminary preparation for donating blood for BRCA1 and BRCA2 is not required for women (over 18 years of age).
- Men over 40 years of age can take a PSA blood test to check for a predisposition to prostate cancer: it is advisable to abstain from sexual activity 2 days before the test. Half an hour before blood sampling, physical overexertion should be avoided.
The analysis is carried out by drawing blood from a vein.
You have 10 more days to complete this analysis completely free of charge!
Here you can download the schedule and addresses for cancer screening.
But, even if you read this post after 09.22.18, I am sure that the Department of Health will still carry out such actions. Medical organizations Health Departments have been holding similar events for several years now, deploying mobile medical units in various areas of the city and in places of public events. Follow the news.
Well, if you didn’t have time, this analysis can be done in any paid laboratory. Perhaps in simple public hospitals Soon they will be doing such analyzes on an ongoing basis.
Most people are of the opinion that there is no disease worse than cancer. Any doctor is ready to challenge this idea, but public opinion is a conservative thing.
And despite the fact that oncological pathology occupies an honorable third place among the causes of disability and death, people will continue to believe for a very long time that there is no disease more terrible and will look for ways to avoid oncology.
It is known that any disease is cheaper and easier to prevent than to treat, and cancer is no exception. And the treatment itself, started in early stage diseases are many times more effective than in advanced cases.
Basic postulates that will allow you not to die from cancer:
- Reducing exposure to carcinogens on the body. Any person, having removed at least some of the oncogenic factors from his life, is able to reduce the risk of cancer pathology by at least 3 times.
- The catchphrase “all diseases are from the nerves” is no exception for oncology. Stress is a trigger for active growth cancer cells. Therefore, avoid nervous shocks, learn to deal with stress - meditation, yoga, a positive attitude towards what is happening, the “Key” method and other psychological training and attitudes.
- Early diagnosis and early treatment. believes that cancer detected on initial stage, we can cure in more than 90% of cases.
Mechanism of tumor development
Cancer in its development goes through three stages:
The origin of cell mutation - initiation
In the process of life, the cells of our tissues constantly divide, replacing dead or spent ones. During division, genetic errors (mutations) and “cell defects” may occur. A mutation leads to a permanent change in a cell's genes, affecting its DNA. Such cells do not turn into normal ones, but begin to divide uncontrollably (in the presence of predisposing factors), forming a cancerous tumor. The causes of mutations are as follows:
- Internal: genetic abnormalities, hormonal imbalances, etc.
- External: radiation, smoking, heavy metals, etc.
The World Health Organization (WHO) believes that 90% of cancer diseases occur under the influence of external reasons. Factors external or internal environment, the impact of which can cause cancer and promote tumor growth are called CARCINOGENS.
The entire stage of the birth of such cells can take several minutes - this is the time of absorption of the carcinogen into the blood, its delivery to the cells, attachment to DNA and transition to an active state active substance. The process is completed when new daughter cells with a changed genetic structure are formed - that’s it!
And this is already irreversible (with rare exceptions), see. But, at this point, the process may stop until favorable conditions are created for the further growth of a colony of cancer cells, since the immune system does not sleep and fights such mutated cells. That is, when the immune system is weakened - powerful stress (most often this is the loss of loved ones), severe infection, and also when hormonal imbalance, after an injury (see), etc. - the body is unable to cope with their growth, then stage 2 begins.
The presence of favorable conditions for the growth of mutating cells - promotion
This is a much longer period (years, even decades) when newly emerged mutated cells predisposed to cancer are ready to multiply to a noticeable extent. cancerous tumor. It is precisely this stage that can be reversible, since everything depends on whether the cancer cells are provided with the necessary conditions for growth. There are many different versions and theories of the causes of cancer development, among which is the connection between the growth of mutated cells and human nutrition.
For example, authors T. Campbell, K. Campbell in the book “ Chinese study, the results of the largest study of the connection between nutrition and health,” present the results of 35 years of research into the connection between oncology and the predominance of protein foods in the diet. They claim that the presence of more than 20% animal proteins (meat, fish, poultry, eggs, dairy products) in the daily diet contributes to intensive growth cancer cells, and vice versa, the presence in daily diet antistimulants (plant foods without heat or cooking) slow down and even stop their growth.
According to this theory, you should be very careful with the various protein diets that are fashionable today. Nutrition should be complete, with an abundance of vegetables and fruits. If a person with stage 0-1 cancer (without knowing it) “sits” on a protein diet (for example, in order to lose weight), he essentially feeds cancer cells.
Development and growth - progression
The third stage is the progressive growth of a group of formed cancer cells, the conquest of neighboring and distant tissues, that is, the development of metastases. This process is irreversible, but it is also possible to slow it down.
Causes of carcinogenesis
WHO divides carcinogens into 3 large groups:
- Physical
- Chemical
- Biological
Science knows thousands of physical, chemical and biological factors that can cause cellular mutations. However, only those whose action is RELIABLY associated with the occurrence of tumors can be considered carcinogens. This reliability must be ensured by clinical, epidemiological and other studies. Therefore, there is the concept of “potential carcinogen”, this is a certain factor whose action can theoretically increase the risk of developing cancer, but its role in carcinogenesis has not been studied or proven.
Physical carcinogens
This group of carcinogens mainly includes various types of radiation.
Ionizing radiation
Scientists have known for a long time that radiation can cause genetic mutations (Nobel Prize 1946, Joseph Möller), but convincing evidence of the role of radiation in the development of tumors was obtained after studying victims of the nuclear bombings of Hiroshima and Nagasaki.
main sources ionizing radiation For modern man the following.
- Natural radioactive background – 75%
- Medical procedures – 20%
- Other – 5%. Among other things, these include radionuclides released into the environment as a result of ground tests nuclear weapons in the middle of the 20th century, as well as those who fell into it after man-made disasters in Chernobyl and Fukushima.
It is useless to influence the natural radioactive background. Modern science does not know whether a person can live completely without radiation. Therefore, you should not trust people who advise reducing the concentration of radon in the house (50% of the natural background) or protecting yourself from cosmic rays.
X-ray examinations carried out for medical purposes are another matter.
In the USSR, fluorography of the lungs (to detect tuberculosis) had to be performed once every 3 years. In most CIS countries, this examination is required annually. This measure reduced the spread of tuberculosis, but how did it affect the overall cancer incidence? There is probably no answer, because no one has addressed this issue.
Also very popular among ordinary people CT scan. At the patient’s insistence, it is done to whoever needs it and who doesn’t need it. However, most people forget that CT is also an x-ray examination, only more technologically advanced. The radiation dose from CT is higher than usual X-ray 5 – 10 times (see). We do not in any way encourage you to give up x-ray studies. You just need to approach their purpose very carefully.
However, there are still force majeure circumstances, such as:
- life in premises built from or decorated with emission-producing materials
- life under high voltage lines
- submarine service
- work as a radiologist, etc.
Ultraviolet radiation
It is believed that the fashion for tanning was introduced in the mid-twentieth century by Coco Chanel. However, back in the 19th century, scientists knew that constant exposure sunlight ages the skin. Not just like that villager look older than their urban peers. They spend more time in the sun.
Ultraviolet radiation causes skin cancer, this is a proven fact (WHO report 1994). But artificial ultraviolet light - solarium - is especially dangerous. In 2003, WHO published a report on concerns about tanning beds and the irresponsibility of manufacturers of these devices. Solariums are prohibited for persons under 18 years of age in Germany, France, Great Britain, Belgium, the USA, and in Australia and Brazil they are completely prohibited. So a bronze tan is probably beautiful, but not at all useful.
Local irritant effect
Chronic trauma to the skin and mucous membranes can cause tumor development. Poor quality dentures can cause lip cancer, and constant friction of clothing against birthmark– melanoma. Not every mole becomes cancer. But if it is in an area of increased risk of injury (on the neck - collar friction, on the face in men - injury from shaving, etc.) you should think about removing it.
Irritation can also be thermal and chemical. Those who eat very hot food put themselves at risk of cancer of the mouth, pharynx and esophagus. Alcohol has an irritating effect, so people who prefer strong strong drinks, as well as alcohol, are at risk of developing stomach cancer.
Household electromagnetic radiation
We are talking about radiation from cell phones, microwave ovens and Wi-Fi routers.
WHO has officially classified cell phones as potential carcinogens. Information about the carcinogenicity of microwaves is only theoretical, and there is no information at all about the effect of Wi-Fi on tumor growth. Quite the contrary, there are more studies demonstrating the safety of these devices than there are fabrications about their harm.
Chemical carcinogens
The International Agency for Research on Cancer (IARC) divides substances used in everyday life and in industry, according to their carcinogenicity, into the following groups (information is provided as of 2004):
- Reliably carcinogenic– 82 substances. Chemical agents whose carcinogenicity is beyond doubt.
- Probably carcinogenic– 65 substances. Chemical agents whose carcinogenicity has a very high degree of evidence.
Possibly carcinogenic– 255 substances. Chemical agents whose carcinogenicity is possible, but questioned. - Probably non-carcinogenic– 475 substances. There is no evidence that these substances are carcinogenic.
- Reliably non-carcinogenic- chemical agents, not proven causing cancer. So far there is only one substance in this group – caprolactam.
Let's discuss the most significant chemicals that cause tumors.
Polycyclic aromatic hydrocarbons (PAHs)
This is a wide group chemical substances, formed during incomplete combustion of organic products. Contained in tobacco smoke, exhaust gases from cars and thermal power plants, stove and other soot, formed during frying food and heat treatment of oil.
Nitrates, nitrites, nitroso compounds
It is a by-product of modern agrochemicals. Nitrates themselves are completely harmless, but over time, as well as as a result of metabolism in the human body, they can turn into nitroso compounds, which in turn are very carcinogenic.
Dioxins
These are chlorine-containing compounds, which are waste from chemical and oil refining industries. May be part of transformer oils, pesticides and herbicides. They can appear when burning household waste, in particular plastic bottles or plastic packaging. Dioxins are extremely resistant to destruction, so they can accumulate in the environment and the human body, especially “loving” dioxins fatty tissue. It is possible to minimize the entry of dioxidins into food if:
- do not freeze food or water in plastic bottles - this way toxins easily penetrate into the water and food
- Do not heat food in plastic containers in the microwave; it is better to use tempered glass or ceramic containers
- Do not cover food with plastic wrap when heating it in the microwave; it is better to cover it with a paper napkin.
Heavy metals
Metals with a density greater than iron. There are about 40 of them in the periodic table, but the most dangerous for humans are mercury, cadmium, lead, and arsenic. These substances enter the environment from waste from mining, steel mills, and chemical production, some heavy metals are found in tobacco smoke and car exhaust fumes.
Asbestos
This common name a group of fine-fiber materials containing silicates as a base. Asbestos itself is completely safe, but its smallest fibers entering the air cause an inadequate reaction of the epithelium with which they come into contact, causing oncology of any organ, but most often it causes the larynx.
An example from the practice of a local therapist: in a house built from asbestos removed from East Germany (rejected in that country) statistics oncological diseases 3 times higher than other houses. This feature of the “phoning” building material was reported by the foreman who worked during the construction of this house (she died of breast cancer after an already operated sarcoma of her toe).
Alcohol
According to scientific research, alcohol does not have a direct carcinogenic effect. However, it can act as a chronic chemical irritant to the epithelium of the mouth, pharynx, esophagus and stomach, promoting the development of tumors in them. Strong alcoholic drinks (over 40 degrees) are especially dangerous. Therefore, those who like to drink alcohol are not only at risk.
Some ways to avoid exposure to chemical carcinogens
Oncogenic chemicals can affect our body in different ways:
Carcinogens in drinking water
According to Rospotrebnadzor data, up to 30% of natural reservoirs contain prohibitive concentrations of substances hazardous to humans. Also don't forget about intestinal infections: cholera, dysentery, hepatitis A, etc. Therefore, it is better not to drink water from natural reservoirs, even boiled.
Old, worn out plumbing systems(of which up to 70% in the CIS) can cause exposure to drinking water carcinogens from soil, namely nitrates, heavy metals, pesticides, dioxins, etc. The best way To protect yourself from them - use household water purification systems, and also ensure timely replacement of filters in these devices.
Water from natural sources (wells, springs, etc.) cannot be considered safe, since the soil through which it passes can contain anything - from pesticides and nitrates, to radioactive isotopes and chemical warfare agents.
Carcinogens in the air
The main oncogenic factors in the inhaled air are tobacco smoke, automobile exhaust gases and asbestos fibers. To avoid breathing carcinogens you need to:
- Quit smoking and avoid secondhand smoke.
- City residents should spend less time outdoors on a hot, windless day.
- Avoid using building materials containing asbestos.
Carcinogens in food
Polycyclic hydrocarbons appear in meat and fish with significant overheating, that is, during frying, especially in fat. Reusing cooking fats significantly increases their PAH content, so domestic and industrial deep fryers are an excellent source of carcinogens. Not only French fries, whites or fried pies bought at a stall on the street are dangerous, but also barbecue prepared with your own hands (see).
Special mention should be made about the kebab. The meat for this dish is cooked over hot coals, when there is no longer any smoke, so PAHs do not accumulate in it. The main thing is to make sure that the kebab does not burn and not to use ignition products in the grill, especially those containing diesel fuel.
- Large amounts of PAHs appear in food when smoked.
- It is estimated that 50 grams of smoked sausage can contain as many carcinogens as the smoke from a pack of cigarettes.
- A jar of sprat will reward your body with carcinogens from 60 packs.
Heterocyclic amines appear in meat and fish during prolonged overheating. The higher the temperature and the longer the cooking time, the more carcinogens appear in the meat. An excellent source of heterocyclic amines is grilled chicken. Also, meat cooked in a pressure cooker will contain more carcinogens than simply boiled meat, since in a hermetically sealed container the liquid boils at a much higher temperature. high temperature than in air - use a pressure cooker less often.
Nitroso compounds spontaneously form in vegetables, fruits and meat from nitrates at room temperature. Smoking, roasting and canning greatly enhance this process. On the contrary, low temperatures inhibit the formation of nitroso compounds. Therefore, store vegetables and fruits in the refrigerator, and also try to eat them raw whenever possible.
Carcinogens in everyday life
The main component of cheap detergents(shampoos, soaps, shower gels, bath foams, etc.) - sodium lauryl sulfate (Sodium Lauryl Sulfate -SLS or Sodium Laureth Sulfate - SLES). Some experts consider it to be oncogenically dangerous. Lauryl sulfate reacts with many components of cosmetic preparations, resulting in the formation of carcinogenic nitroso compounds (see).
The main source of mycotoxins is the “toad”, which “strangles” the housewife when she sees slightly rotten cheese, bread or a small spot of mold on jam. Such products must be thrown away, since removing mold from food only saves you from eating the fungus itself, but not from the aflatoxins that it has already released.
On the contrary, low temperatures slow down the release of mycotoxins, so greater use of refrigerators and cold cellars should be made. Also, do not eat rotten vegetables and fruits, as well as products with expired expiration dates.
Viruses
Viruses that can transform infected cells into cancer cells are called oncogenic. These include.
- Epstein-Barr virus – causes lymphomas
- Hepatitis B and C viruses can cause liver cancer
- Human papillomavirus (HPV) is a source of cervical cancer
In fact, there are much more oncogenic viruses; only those whose influence on tumor growth has been proven are listed here.
Vaccines can provide protection against some viruses, for example, against hepatitis B or HPV. Many oncogenic viruses are sexually transmitted (HPV, hepatitis B), therefore, in order not to give yourself cancer, you should avoid sexually risky behavior.
How to avoid exposure to carcinogens
From all that has been said, several simple recommendations emerge that will significantly reduce the influence of oncogenic factors on your body.
- Stop smoking.
- How women can avoid breast cancer: give birth to children and breastfeed for a long time, refuse replacement therapy hormones in postmenopause.
- Drink only high-quality alcohol, preferably not very strong.
- Don't overuse beach holiday, refuse to visit the solarium.
- Don't eat very hot food.
- Eat less fried and grilled foods, and do not reuse fat from frying pans and deep fryers. Give preference to boiled and stewed foods.
- Make more use of your refrigerator. Do not purchase products from dubious places and markets; monitor their expiration dates.
- Drink only clean water, use household water purification filters more widely (see).
- Reduce the use of cheap cosmetics and personal hygiene products and household chemicals (see).
- When carrying out finishing work at home and in the office, give preference to natural building materials.
How to avoid getting cancer? Let us repeat - if you remove at least some carcinogens from your everyday life, you can reduce the risk of cancer by 3 times.
What causes one patient's cancer disease to be more aggressive than another? Why do some people have cancer that is resistant to chemotherapy? Genetic mutation The MAD2 protein may help answer both of these questions.
Researchers engineered an inherited mutation in the MAD2 gene in human cancer cells, which is responsible for the process of cancer cell division and proliferation. As a result, the mutation made the tumor cells that were born from existing ones very variable in their properties, which by all indications had characteristics consistent with more aggressive forms of cancer. In addition, the newborn mutated cancer cells were resistant to toxins (chemotherapy). The results of this study, published in the January 18 issue of the journal Nature, have important implications for the development of new drugs and could help create a new “marker gene” to diagnose the aggressiveness of tumors and detect them at an early stage.
Back in 1996, Dr. Robert Benezra and Yong Lee identified the MAD2 gene as a class of proteins responsible for some of the functions of division and budding of newborn cancer cells from the uterine cell. They guarantee uniform distribution chromosomes to two daughter cells during the process of cell division. The loss of this normal division mechanism leads to unstable forms in which entire chains of chromosomes can be lost or extra ones added. Cancers that exhibit this type of chromosome instability are usually more aggressive and have an uncertain prognosis regarding the patient's future life prospects. Correlations between chromosome instability and MAD2 loss have been identified in human colon cancer cells. However, previously there was no evidence that there is a connection between these phenomena. Now, scientists know that the loss of MAD2 on maternal cancer cells creates chromosomal instability for newborn cancer cells.
For example, mice with complete absence MAD2 gene die even during embryonic development. Even one copy of the MAD2 gene led to the development of cancer in mice. Uniquely, this mutation led to the development of lung cancer in mice, despite the fact that the disease is extremely rare in them. Why this affected lung tissue is not yet known, but it does show that MAD2 is involved in cancer development.
The opinions of a number of other specialists in this field on the results of this study indicate other fundamental possibilities that make it possible to explain the reasons for the effectiveness of cancer treatment in some and the ineffectiveness, and sometimes even negative effects of chemotherapy in others.
In particular, one patient with cancer has, for example, unstable and mutation-prone (due to the weakness of the MAD2 gene) cancer cells of a certain type, and another has the same form of cancer, but with resistant forms. Thus, chemotherapy treatment for the first patient will most likely have no effect in destroying the tumor or slowing its growth, and may even cause an accelerated response to further cancer progression. At the same time, in another patient, a course of chemotherapy can have a positive effect and even lead to recovery.
The latter circumstance is extremely rare, which may indicate that the majority of people with cancer have unstable forms of cancer cells, which are sometimes simply impossible to influence in combination with various types of therapies. Unstable forms exist, apparently, due to the main factors that become the causes of the development of cancer. As a rule, these are carcinogens and poisons, which modern civilization poisons himself. That is, cancer cells themselves undergo constant mutations, just as healthy cells develop into malignant ones due to mutations.
Probably for the same reason, no solution has yet been found to combat this fatal disease, which ranks second as the leading cause of death, after cardiovascular diseases.
The human body is made up of many tiny elements that make up the entire body. They are called cells. Tissue and organ growth in children or restoration functional system in adults, the result of cell division.
The emergence of cancer cells is associated with a failure in the orderliness of the process of formation and death of ordinary cells, which is the basis healthy body. Cancer cell division ‒ a sign of disruption of cyclicity in the basis of tissues.
Features of the cell division process
Cell division is the exact reproduction of identical cells, which occurs due to submission to chemical signals. In normal cells cell cycle controlled complex system signaling pathways by which a cell grows, reproduces its DNA, and divides.
One cell divides into two identical ones, from which four are formed, etc. In adults, new cells are formed when the body needs to replace aging or damaged ones. Many cells live for a set period of time and are then programmed to undergo a process of death called apoptosis.
Such coherence of the cells is aimed at correcting possible errors in their life cycle. If this becomes impossible, the cell kills itself. Such sacrifice helps to keep the body healthy.
Cells of different tissues divide at different rates. For example, skin cells renew themselves relatively quickly, while nerve cells divide very slowly.
How do cancer cells divide?
Cancer cell
Hundreds of genes control the process of cell division. Normal growth requires a balance between the activity of those genes that are responsible for cell proliferation and those that suppress it. The viability of the organism also depends on the activity of genes that signal the need for apoptosis.
Over time, cancer cells become increasingly resistant to the controls that support normal tissue. As a result, atypical cells divide faster than their predecessors and are less dependent on signals from other cells.
Cancer cells even escape programmed cell death, despite the fact that disruption of these functions makes them a prime target of apoptosis. On late stages cancer, cancer cells divide With increased activity, breaking through the boundaries of normal tissues and metastasizing to new areas of the body.
Causes of cancer cells
There are many various types cancer, but all of them are associated with uncontrolled cell growth. This situation is caused by the following factors:
- atypical cells stop dividing;
- do not follow signals from other normal cells;
- stick very well together and spread to other parts of the body;
- comply with behavioral characteristics mature cells, but remain immature.
Gene mutations and cancer
Most cancers are caused by changes or damage to genes during cell division, in other words, mutations. They represent errors that have not been fixed. Mutations affect the structure of a gene and stop it from working. They have several options:
- The simplest type of mutation is a substitution in the DNA structure. For example, thiamine can replace adenine.
- Removal or duplication of one or more basic elements (nucleotides).
Gene mutations that occur when cancer cells divide
There are two main causes of gene mutations: random or hereditary.
Individual mutations:
Majority cancer diseases occurs due to random genetic changes in cells as they divide. They are called sporadic, but can depend on factors such as:
- cell DNA damage;
- smoking;
- influence of chemicals (toxins), carcinogens and viruses.
Most of these mutations occur in cells called somatic cells and are not passed on from parent to child.
Hereditary mutations:
This species is called “germline mutation” because it is present in the germ cells of the parents. Men and women who are carriers of this species have a 50% chance of passing on the mutation gene to their children. But only in 5-10% of cases does this cause cancer.
Cancer cell division and types of cancer genes
Scientists have discovered 3 main classes of genes that affect the division of cancer cells, which can cause cancer.
- Oncogenes:
These structures, when dividing, cause cells to grow out of control, which promotes the growth of cancer cells. Oncogenes of damaged versions of normal genes are called protogens. Each person has 2 copies of each gene (one from each parent). Onko gene mutations are dominant, meaning that an inherited defect in one copy of the protogens can lead to cancer, even if the second copy is normal.
- Tumor suppressor genes:
They generally protect against cancer and act as brakes on the growth of abnormal cells. If tumor suppressor genes are damaged, they do not work properly. In this regard, cell division and apoptosis become uncontrolled.
Almost 50% of all cancers are thought to be due to a damaged or missing tumor suppressor gene.
- DNA repair genes:
They are responsible for repairing damaged genes. DNA repair genes fix errors that occur during cell division. When these protective structures are damaged, they cause recessive gene mutations in both copies of the gene, which affects the risk of developing cancer.
Metastasis and division of cancer cells
As cancer cells divide, they invade nearby tissues. Oncology of this phenomenon is characterized by the ability primary tumor enter the bloodstream and lymphatic system. When the body's defenses do not detect a threat in time, it spreads to distant areas of the body, which is called metastasis.
