Heredity of cancer

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Cancer is a genetic disease. In some cases, cancer genetics is due to family members being exposed to an increased risk of cancer.

1. Cancer genetics

Cancer is a disease in which cells grow out of control. This happens because of changes in certain genes inside the cell. Genes are pieces of DNA that control how cells make proteins the body needs to function, as well as how cells are kept in balance. Genes affect a number of things like hair color, eye color, and height. They can also affect your risk of certain diseases, such as cancer.
An abnormal change in a gene is called a mutation. A gene mutation can affect how it works. For example, a mutation can prevent a gene from working. Or it can make the gene always on (even if it's not needed). Either way, these can cause problems inside the cell. Gene mutations can be inherited or acquired.
Inherited genetic mutations are present in the egg or sperm cell that forms. When an egg is fertilized by a sperm, it produces a cell that then divides many times. This type of mutation is present in every cell (including eggs or sperm) and can therefore be passed on to the next generation. Somatic mutations are not derived from parents. This type of mutation is not present in egg or sperm cells, so it is not passed on to the next generation. Acquired mutations are much more common than inherited mutations. Most cancers are caused by acquired mutations. Many familial cancer syndromes are caused by inherited mutations in tumor suppressor genes. These are genes that normally keep cells under control by slowing down how often they divide (to make new cells) and correcting DNA errors.
You have 2 copies of most genes from your father and mother. When someone inherits an abnormal copy of a gene, the cells begin to develop the mutation. Usually this is not a problem, since the other gene copy is still active. But if the other copy of the gene stops working (for example, due to an acquired mutation), the function of the gene can be completely lost. When the gene that shuts down is a tumor suppressor gene, cells can grow out of control, possibly leading to cancer.
A person born with an inherited mutation in one copy of a tumor suppressor gene would only have to receive a mutation in another copy of that gene for it to not work. This is more likely than a mutation in both copies of the gene, so this person will have a higher risk of cancer than someone born without the gene mutation.

2. How to recognize the genetic nature of cancer?

Cancer is a common disease nowadays. In fact, in the United States, about 3 people have 1 person with cancer, so it is not uncommon for a family to have many members with cancer.
When multiple cases of cancer run in a family, this may be random, or it may also be that members have been exposed to a certain risk factor, such as smoking. Or it could be due to an interaction between certain genes and exposure, such as some people inheriting a gene change, that makes it harder for their body to get rid of the toxins in cigarette smoke.
Although rare, some family members have cancer related to inherited gene mutations, also known as familial cancer syndrome. Familial cancer syndromes can be identified by the following factors:
Members with the same type of cancer (especially if it is an uncommon or rare cancer) The cancer occurs in younger than normal ages (such as colon cancer at age 20) A person with more than 1 type of cancer (a woman with breast and ovarian cancer) Cancer occurring in both pairs of organs ( such as both eyes, both kidneys, or both breasts) Cancer occurs over many generations (as in grandfathers, fathers, and sons) If a close family member, such as a parent or sibling, has had cancer , which puts you at a higher risk of cancer than distant relatives. Even if the cancer is caused by a genetic mutation, the chances of it being passed on to you are lower with distant relatives. It's important to look at each issue clearly, for example, if two people in a family have cancer, it's more genetically related.
The age at which cancer is diagnosed is also important. For example, colon cancer is rare in people under the age of 30. Having a close relative under the age of 30 with colon cancer can be a sign of an inherited cancer syndrome. On the other hand, prostate cancer is very common in elderly men, so if both your father and brother were found to have prostate cancer when they were in their 80s, it is less likely. due to genetic changes.
Certain types of benign (noncancerous) tumors and medical conditions are also sometimes part of familial cancer syndromes. For example, people with multiple endocrine neoplasia type II syndrome (MEN II) have an increased risk of a certain type of thyroid cancer.
When multiple relatives have the same type of cancer, it's important to note whether cancer can be associated with a risk factor such as smoking. For example, lung cancer is often caused by smoking, so cases of lung cancer in a family with heavy smokers are more likely to be caused by smoking than by genetic changes.

3. Some cancer syndromes are hereditary

There are many family cancer syndromes, such as:
Hereditary breast and ovarian cancer (HBOC) syndrome
In some families, many women develop breast and ovarian cancer. Usually these cancers are found in women who are younger than the normal age. Some cases may have both breast cancer (both sides) or both breast cancer and ovarian cancer. This is called hereditary breast and ovarian cancer (HBOC).
Usually, HBOC is caused by an inherited mutation in the BRCA1 or BRCA2 gene. (Some families have HBOC based on a history of cancer, but don't have mutations in either of these genes. Scientists believe there may also be other genes that can cause HBOC.
Cancer risk. Breast and ovarian cancer is very high in women with mutations in BRCA1 or BRCA2, but it tends to be higher with mutations in BRCA1. Along with breast cancer and ovarian cancer, this syndrome can also lead to cancer. fallopian tube cancer, primary peritoneal cancer, pancreatic cancer, and prostate cancer Like some people, pancreatic cancer and prostate cancer can be detected with mutations in either gene, but is more common in people with the BRCA2 mutation In the US, the BRCA gene mutation is more common in Ashkenazi Jews breast and ovarian cancer, you should consult genetic counseling packages to estimate your risk of having a mutation in one of the BRCA genes. the patient's cancer history and their family history of cancer. If they are at high risk, they may choose to be tested. If the mutation is present, a woman is at increased risk for breast and ovarian cancer (as well as some other cancers). She can then look at steps to find cancer early and even reduce the risk of cancer.
Because breast cancer is so rare in men, men with this cancer often receive genetic counseling and testing for BRCA mutations. While having the mutation is less likely to affect a man's future health than a woman's, it can affect the risk of some cancers, such as prostate and pancreatic cancer.
If someone has a BRCA mutation, it means that their close relatives (parents, siblings and children) have a 50% chance of having the mutation as well. So they need to be screened, or even without testing, to be able to start doing early screening for some cancers or take other precautions to reduce their risk of cancer.
HBOC is not the only familial cancer syndrome that can cause breast or ovarian cancer.
Lynch syndrome (inherited colorectal cancer)
The most common genetic syndrome that increases the risk of colon cancer is Lynch syndrome, also known as hereditary non-colon cancer ( HNPCC). People with this syndrome have an increased risk of colorectal cancer.
Lynch syndrome also leads to an increased risk of endometrial cancer, ovarian cancer, stomach cancer, cancer of the small intestine, pancreas, kidney, brain, ureter (the tube that carries urine from the kidney to the bladder)
Lynch syndrome can be caused by a mutation in any of the mismatch repair (MMR) genes, including MLH1, MSH2, MSH6, PMS1, and PMS2. This gene is normally involved in repairing damaged DNA.When one of these genes is not working, the faulty DNA is not repaired, which can lead to other gene mutations and eventually to cancer.
Mutations in the genes that cause Lynch syndrome can then be checked with genetic testing
For people with colorectal or endometrial cancer, surgery for the tumor can be checked. to detect changes in the MMR gene or other changes when one of these genes is faulty, known as microsatellite instability (MSI). I, which means the person probably doesn't have Lynch syndrome. But if this change occurs, the person is at risk for Lynch syndrome.
People with genetic mutations associated with Lynch syndrome can get colorectal cancer screening at a young age or take certain steps to prevent cancer. Women with Lynch syndrome can begin screening for endometrial cancer or take other steps to prevent this cancer.
If someone has Lynch syndrome, it means that their next of kin (parents, siblings, and children) also has a 50% chance of having the mutation. So they need to be screened, or even without testing, to be able to start doing early screening for some cancers or take other precautions to reduce their risk of cancer.

Li-Fraumeni syndrome
Li-Fraumeni syndrome is a rare genetic syndrome that can lead to the development of several cancers, including sarcoma, leukemia, brain, and adrenocortical cancers. ...
People with Li-Fraumeni syndrome can also get cancer more than once in their lifetime. It seems that the risk of other cancers in these patients is higher with radiation therapy, so doctors who treat these patients often try to avoid radiation therapy when possible.
This syndrome is usually caused by an inherited mutation in the TP53 gene, which is a tumor suppressor gene. A normal TP53 gene makes a protein that helps stop abnormal cells from growing.
Li-Fraumeni syndrome can also be caused by mutations in a tumor suppressor gene called CHEK2, which normally helps stop DNA-damaged cells from growing.
If someone has Li-Fraumeni syndrome, their close relatives (especially children) are also at risk for the mutation. So they need to be screened, or even without testing, to be able to start doing early screening for some cancers or take other precautions to reduce their risk of cancer.
Cancer is a dangerous genetic disease, now some cancers, if detected and treated at an early stage, the recovery rate will be very high. Therefore, if there are signs of unstable health or a family history of cancer, you should go for regular cancer screening or general health check-ups.
Currently, Vinmec International General Hospital is implementing cancer screening packages, helping to detect and treat cancers early even when there are no symptoms.
Customers wishing to be examined at Vinmec International General Hospital can register for an examination at Vinmec Hospitals and Clinics nationwide or register for examination HERE.
Reference source: cancer.or