In most cases of prostate cancer, these genetic changes are acquired during a man's lifetime and are present only in certain cells in the prostate. These changes, which are called somatic variants, are not inherited.
Somatic variants in many different genes have been found in prostate cancer cells. Less commonly, genetic changes present in essentially all of the body's cells increase the risk of developing prostate cancer. These genetic changes, which are classified as germline variants, are usually inherited from a parent. In people with germline variants, changes in other genes, together with environmental and lifestyle factors, also influence whether a person will develop prostate cancer.
Men with variants in these genes have a high risk of developing prostate cancer and, in some cases, other cancers during their lifetimes. For this reason, the BRCA1 and BRCA2 proteins are considered to be tumor suppressors, which means that they help keep cells from growing and dividing too fast or in an uncontrolled way.
Variants in these genes impair the cell's ability to fix damaged DNA, allowing potentially damaging variants to persist. As these defects accumulate, they can trigger cells to grow and divide uncontrollably and form a tumor. The HOXB13 gene provides instructions for producing a protein that attaches binds to specific regions of DNA and regulates the activity of other genes. On the basis of this role, the protein produced from the HOXB13 gene is called a transcription factor. HOXB13 gene variants may result in impairment of the protein's tumor suppressor function, resulting in the uncontrolled cell growth and division that can lead to prostate cancer.
Inherited variations in dozens of other genes have been studied as possible risk factors for prostate cancer. Others act as tumor suppressors through different pathways.
Changes in these genes probably make only a small contribution to overall prostate cancer risk. However, researchers suspect that the combined influence of variations in many of these genes may significantly impact a person's risk of developing this form of cancer. In many families, the genetic changes associated with hereditary prostate cancer are unknown.
Identifying additional genetic risk factors for prostate cancer is an active area of medical research. In addition to genetic changes, researchers have identified many personal and environmental factors that may contribute to a person's risk of developing prostate cancer. These factors include a high-fat diet that includes an excess of meat and dairy and not enough vegetables, a largely inactive sedentary lifestyle, obesity, excessive alcohol use, or exposure to certain toxic chemicals.
A history of prostate cancer in closely related family members is also an important risk factor, particularly if the cancer occurred at an early age.
Many cases of prostate cancer are not related to inherited gene changes. These cancers are associated with somatic variants that occur only in certain cells in the prostate. When prostate cancer is related to inherited gene changes, the way that cancer risk is inherited depends on the gene involved.
For example, variants in the BRCA1 , BRCA2 , and HOXB13 genes are inherited in an autosomal dominant pattern , which means one copy of the altered gene in each cell is sufficient to increase a person's chance of developing cancer.
In other cases, the inheritance of prostate cancer risk is unclear. It is important to note that people inherit an increased risk of cancer, not the disease itself.
Not all people who inherit variants in these genes will develop cancer. Genetics Home Reference has merged with MedlinePlus. Learn more. The information on this site should not be used as a substitute for professional medical care or advice. Still, a family history does raise the risk of prostate cancer. That risk escalates for men with several affected relatives, especially if they were young when cancer struck.
Over past decades, scientists have learned that some prostate cancer that runs in families is hereditary. Mutations in these two genes are best known for causing breast and ovarian cancer in women. A simple blood test can help determine if you carry a worrisome gene. If appropriate, your doctor can refer you to a genetic counselor to help you decide if testing is right for you and to help you understand the results.
If genetic testing does reveal that you have an inherited risk of prostate cancer, early screening with a digital rectal exam and PSA blood tests could help doctors find any prostate cancer that develops; and, if cancer is ever suspected, your doctor may recommend that a biopsy be performed. Some people with several known risk factors never develop cancer, while others with no known risk factors do.
Knowing your risk factors and talking about them with your doctor may help you make more informed lifestyle and health care choices. The risk of prostate cancer increases with age, especially after age Older adults who are diagnosed with prostate cancer can face unique challenges, specifically with regard to cancer treatment.
For more information, please visit Cancer. Black men in the United States, and other men of African ancestry, are diagnosed with prostate cancer more than men of other races.
Black men are more likely to die from prostate cancer than white men. North American or northern European location. Prostate cancer occurs most often in North America and northern Europe.
It also appears that prostate cancer is increasing among Asian people living in urbanized environments, such as Hong Kong, Singapore, and North American and European cities, particularly among those who have a lifestyle with less physical activity and a less healthy diet.
Family history. This type of prostate cancer develops because of a combination of shared genes and shared environmental or lifestyle factors. Hereditary prostate cancer occurs when changes in genes, or mutations, are passed down within a family from 1 generation to the next. Hereditary prostate cancer may be suspected if a family history includes any of the following characteristics:. If someone has a first-degree relative—meaning a parent, sibling, or child—with prostate cancer, their risk of developing prostate cancer is 2 to 3 times higher than the average risk.
This risk increases even further with the number of relatives diagnosed with prostate cancer. Hereditary breast and ovarian cancer HBOC syndrome. However, people with HBOC also have an increased risk of developing breast cancer and a more aggressive form of prostate cancer.
Genetic testing may only be appropriate for families with prostate cancer that may also have HBOC. If you are concerned about this based on your own family history, please talk with a genetic counselor or doctor for more information. Other genetic changes. However, none of them has been directly shown to cause prostate cancer or be specific to this disease. Research to identify genes associated with an increased risk of prostate cancer is ongoing, and researchers are constantly learning more about how specific genetic changes can influence the development of prostate cancer.
At present, there are no genetic tests available to determine someone's chance of developing prostate cancer. Agent Orange exposure.
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