DEFINITION
TUMOR ANTIGEN
Antigens are foreign substances known and is a target to be destroyed by the immune system. Antigen found on the surface of all cells, but in normal circumstances, a person's immune system does not react to his cell alone.
If a cell becomes cancerous, a new antigen (which is not recognized by the immune system) appears in the cell surface. The immune system may recognize new antigens, called tumor antigen, as foreign and can transport or destroy cancer cells. But the immune system is functioning baikpun not always able to destroy all the cancer cells.
Tumor antigens have been found in several types of cancer, ie malignant melanoma, osteosarcoma (bone cancer) and some gastrointestinal cancers. Cancer patients had antibodies against tumor antigens. Antigens are usually not sufficient immune responses for the control of cancer. It seems that the antibodies are not able to destroy cancer and sometimes even stimulate growth.
Antigens are released into the bloodstream by some cancers can be found in blood tests. Antigen is sometimes called a tumor marker (tumor marker). More widely used tumor markers in the diagnosis and treatment of cancer. For example, blood tests may help clarify whether cancer treatment is effective or not. If tumor markers are no longer found in the blood sample, the possibility of treatment has been successful. If the tumor marker disappears and then appears again, the possibility of cancer has relapsed.
Antigen karsinoembrionik (Carcinoembryonik antigen, CEA) is a tumor antigen is found in the blood of patients with cancer of the colon, breast, pancreas, bladder, ovary or cervix. High levels of antigen can also be found in heavy cigarette smokers and patients with liver cirrhosis or ulcerative colitis. Because of the high levels of CEA does not necessarily indicate the presence of cancer. Measurement of CEA levels in someone who has been undergoing treatment for cancer, it helps to know the recurrence of cancer.
Alpha-fetoprotein (AFP) is normally produced by the liver cells, are found in the blood of patients with liver cancer (hepatoma). AFP is often found in people with certain ovarian cancer or testicular cancer and in children and young adults suffering from pituitary gland tumor.
Beta-human chorionic gonadotropin (?-HCG) is a hormone produced during pregnancy, which is the basis for prenatal care.
This hormone is also found in women who had cancer that originates in the placenta and in men suffering from testicular cancer. ?-HCG is a very sensitive tumor marker. Its use in monitoring the effects of treatment have helped to improve the cure rate of this cancer by more than 95%.
Levels of prostate-specific antigen (PSA) in men with high benign prostate enlargement and is higher in men with prostate cancer. What causes high levels of this antigen is not yet clear, but men with elevated PSA levels should undergo further examination for prostate cancer. Monitoring of PSA levels after a cancer treatment can be explained if the cancer has come back or not.
CA-125 levels in the blood increased in women with ovarian diseases, including cancer. Because ovarian cancer is often difficult to diagnose, some experts advocate for cancer screening test for CA-125 in women over 40 years. However, these screening tests are less reliable because it is less sensitive and less specific.
In breast cancer, increased levels of CA 15-3; pancreatic cancer increased levels of CA 19-5; levels in multiple myeloma and beta2;-microglobulin increased and testicular cancer, increased levels of lactate dehydrogenase. But none of that can be used for cancer screening. This check is used to monitor the response to treatment in patients with cancer.
Immunotherapy
To improve the ability of the immune system to find and destroy cancer, researchers have created a biological response modifier (biological response modifiers).
They are used for the following functions:
• Stimulate the body's anti-tumor response by increasing the number of killer cells or tumor produces 1 or more of the chemical messenger (mediator)
• It directly serves as an agent or a tumor killer chemical messengers
• Reducing the body's normal mechanisms to suppress the immune response
• Changing the tumor cells to increase their likelihood of triggering an immune response or make tumor cells more likely to be destroyed by the immune system
• Improving the body's tolerance to radiation therapy or the chemicals used in chemotherapy.
Biological response modifiers of the best known and most widely used are interferon. Under normal circumstances, almost all human cells produce interferon, interferon but can also be made by recombinant molecular biology techniques.
Although the mechanism of action is not fully clear, interferon plays a role in the treatment of some cancers. Outstanding response (including healing) has occurred in approximately 30% of patients with Kaposi's sarcoma, 20% of young people with chronic leukemia mielogenous and 15% of patients with renal cell carcinoma.
Interferon prolong the disease-free period which is expected in patients who experienced healing from multiple myeloma and some forms of lymphoma.
In therapy killer cells (killer cell therapy), lymphocytes from cancer patients are removed from the blood sample. In the laboratory, conducted for exposure to lymphocytes with interleukin-2 (a T cell growth factor), to create a cell-lymphokine activated killer cells, which will be injected back into the patient through a vein. These cells are better trained than the body's natural cells to find and destroy cancer cells.
Approximately 25-30% of patients with malignant melanoma or renal cancer respond well to therapy lymphokine activated killer cells, but treatment is still under investigation.
Therapeutics (antibodies) to increase the production of humoral antibodies by the body. Materials such as tuberculosis are attenuated bacteria, which are known to increase the immune response, has been attempted in several cancers. Tuberculosis bacteria inject directly into a melanoma is almost always causes shrinking of cancer. Sometimes the effect is spread to the tumor that had metastasized throughout the body (metastasis).
Tuberculosis bacterium has also been successfully used to control bladder cancer that has not spread to the bladder wall. Other experimental approaches linking tumor-specific antibodies with anticancer drugs. Antibodies made in the laboratory and injected into the patient, will bring drugs into cancer cells.
Another option is a laboratory-made antibody that can be attached to both the cancer cells and the killer lymphocytes and thus integrate both lymphocyte killer cells to destroy cancer cells. Recent research gives hope for new treatments. Some of them use part of oncogenes, which are important in the regulation and growth of cells.
TUMOR ANTIGEN
Antigens are foreign substances known and is a target to be destroyed by the immune system. Antigen found on the surface of all cells, but in normal circumstances, a person's immune system does not react to his cell alone.
If a cell becomes cancerous, a new antigen (which is not recognized by the immune system) appears in the cell surface. The immune system may recognize new antigens, called tumor antigen, as foreign and can transport or destroy cancer cells. But the immune system is functioning baikpun not always able to destroy all the cancer cells.
Tumor antigens have been found in several types of cancer, ie malignant melanoma, osteosarcoma (bone cancer) and some gastrointestinal cancers. Cancer patients had antibodies against tumor antigens. Antigens are usually not sufficient immune responses for the control of cancer. It seems that the antibodies are not able to destroy cancer and sometimes even stimulate growth.
Antigens are released into the bloodstream by some cancers can be found in blood tests. Antigen is sometimes called a tumor marker (tumor marker). More widely used tumor markers in the diagnosis and treatment of cancer. For example, blood tests may help clarify whether cancer treatment is effective or not. If tumor markers are no longer found in the blood sample, the possibility of treatment has been successful. If the tumor marker disappears and then appears again, the possibility of cancer has relapsed.
Antigen karsinoembrionik (Carcinoembryonik antigen, CEA) is a tumor antigen is found in the blood of patients with cancer of the colon, breast, pancreas, bladder, ovary or cervix. High levels of antigen can also be found in heavy cigarette smokers and patients with liver cirrhosis or ulcerative colitis. Because of the high levels of CEA does not necessarily indicate the presence of cancer. Measurement of CEA levels in someone who has been undergoing treatment for cancer, it helps to know the recurrence of cancer.
Alpha-fetoprotein (AFP) is normally produced by the liver cells, are found in the blood of patients with liver cancer (hepatoma). AFP is often found in people with certain ovarian cancer or testicular cancer and in children and young adults suffering from pituitary gland tumor.
Beta-human chorionic gonadotropin (?-HCG) is a hormone produced during pregnancy, which is the basis for prenatal care.
This hormone is also found in women who had cancer that originates in the placenta and in men suffering from testicular cancer. ?-HCG is a very sensitive tumor marker. Its use in monitoring the effects of treatment have helped to improve the cure rate of this cancer by more than 95%.
Levels of prostate-specific antigen (PSA) in men with high benign prostate enlargement and is higher in men with prostate cancer. What causes high levels of this antigen is not yet clear, but men with elevated PSA levels should undergo further examination for prostate cancer. Monitoring of PSA levels after a cancer treatment can be explained if the cancer has come back or not.
CA-125 levels in the blood increased in women with ovarian diseases, including cancer. Because ovarian cancer is often difficult to diagnose, some experts advocate for cancer screening test for CA-125 in women over 40 years. However, these screening tests are less reliable because it is less sensitive and less specific.
In breast cancer, increased levels of CA 15-3; pancreatic cancer increased levels of CA 19-5; levels in multiple myeloma and beta2;-microglobulin increased and testicular cancer, increased levels of lactate dehydrogenase. But none of that can be used for cancer screening. This check is used to monitor the response to treatment in patients with cancer.
Immunotherapy
To improve the ability of the immune system to find and destroy cancer, researchers have created a biological response modifier (biological response modifiers).
They are used for the following functions:
• Stimulate the body's anti-tumor response by increasing the number of killer cells or tumor produces 1 or more of the chemical messenger (mediator)
• It directly serves as an agent or a tumor killer chemical messengers
• Reducing the body's normal mechanisms to suppress the immune response
• Changing the tumor cells to increase their likelihood of triggering an immune response or make tumor cells more likely to be destroyed by the immune system
• Improving the body's tolerance to radiation therapy or the chemicals used in chemotherapy.
Biological response modifiers of the best known and most widely used are interferon. Under normal circumstances, almost all human cells produce interferon, interferon but can also be made by recombinant molecular biology techniques.
Although the mechanism of action is not fully clear, interferon plays a role in the treatment of some cancers. Outstanding response (including healing) has occurred in approximately 30% of patients with Kaposi's sarcoma, 20% of young people with chronic leukemia mielogenous and 15% of patients with renal cell carcinoma.
Interferon prolong the disease-free period which is expected in patients who experienced healing from multiple myeloma and some forms of lymphoma.
In therapy killer cells (killer cell therapy), lymphocytes from cancer patients are removed from the blood sample. In the laboratory, conducted for exposure to lymphocytes with interleukin-2 (a T cell growth factor), to create a cell-lymphokine activated killer cells, which will be injected back into the patient through a vein. These cells are better trained than the body's natural cells to find and destroy cancer cells.
Approximately 25-30% of patients with malignant melanoma or renal cancer respond well to therapy lymphokine activated killer cells, but treatment is still under investigation.
Therapeutics (antibodies) to increase the production of humoral antibodies by the body. Materials such as tuberculosis are attenuated bacteria, which are known to increase the immune response, has been attempted in several cancers. Tuberculosis bacteria inject directly into a melanoma is almost always causes shrinking of cancer. Sometimes the effect is spread to the tumor that had metastasized throughout the body (metastasis).
Tuberculosis bacterium has also been successfully used to control bladder cancer that has not spread to the bladder wall. Other experimental approaches linking tumor-specific antibodies with anticancer drugs. Antibodies made in the laboratory and injected into the patient, will bring drugs into cancer cells.
Another option is a laboratory-made antibody that can be attached to both the cancer cells and the killer lymphocytes and thus integrate both lymphocyte killer cells to destroy cancer cells. Recent research gives hope for new treatments. Some of them use part of oncogenes, which are important in the regulation and growth of cells.
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