Breast Cancer, TP53, All Mutations

View:
Expand Collapse Breast Cancer  - General Description Breast cancer is a malignant tumor that usually forms in the glands that make milk (lobules) and the tubes (ducts) that carry milk to the nipple. This year about 231,8400 women (and 2,000 men) in the U.S. will be told by a doctor that they have breast cancer. Half of these people will be at least 61 years old. However, more than 10 times as many women, about 2.7 million, remain alive today after having been diagnosed with breast cancer.

Breast cancer is not one disease and is currently classified into 3 subtypes based on the receptors present on the surface of the cancer cell. If the tumor is positive for estrogen and/or progesterone receptors, it is called "hormone receptor breast cancer". In that case, drugs that block the hormones, such as tamoxifen or aromatase inhibitors, might work best initially. If the tumor is positive for another type of receptor, called HER2 (or ERBB2), it is called "HER2 positive breast cancer", and certain targeted therapies that block HER2, such as the medications trastuzumab (Herceptin), pertuzumab (perjeta), T-DM1 (Kadcyla), and lapatanib (Tykerb) might work best and are recommended by the FDA. If the tumor is negative for HER2, estrogen, and progesterone receptors, it is called "triple negative breast cancer".

Over time, breast cancer (and other tumors) can spread from the site where it started (the primary tumor) in 3 ways. First, breast cancer cells can invade the normal tissue surrounding the tumor. Second, breast cancer cells can enter the lymph system and travel through lymph vessels to distant parts of the body. Third, the breast cancer cells can get into the blood stream and travel to other places in the body. In these distant places, the breast cancer cells cause secondary (metastatic) tumors to grow. The main sites where breast cancer spreads are the lungs, liver and bones. There is a lot of ongoing research to identify other receptors and mutations that are actionable through treatment using appropriate new targeted therapies that could be developed against the cancer.

Source: National Cancer Institute, 2015
Breast cancer is the most common non-cutaneous cancer among women in the United States. This year about 231,840 women (and 2,000 men) in the U.S. will be told by a doctor that they have breast cancer. Half of these people will be at least 61 years old. However, more than 10 times as many women, about 2.7 million, remain alive today after having been diagnosed with breast cancer.

Germline mutations in either the BRCA1 or BRCA2 gene confer an increased risk of breast and/or ovarian cancer. In addition, mutation carriers may be at increased risk of other primary cancers. Genetic testing is available to detect mutations in members of high-risk families. Such individuals should first be referred for counseling. Breast cancer is commonly treated by various combinations of surgery, radiation therapy, chemotherapy and hormone therapy.

Over the past years, significant major strides in understanding the biology of breast cancer have translated into actionable targeted therapies. For metastatic hormone receptor positive breast cancer, FDA approved therapies include tamoxifen, a selective estrogen modulator, aromatase inhibitors including exemestane, letrozole, and anastrozole, fulvestrant, a selective estrogen receptor blocker, and more recently everoliumus, a mTOR inhibitor, in combination with exemestane.

Despite significant improvements in the treatment of breast tumors, novel therapies and treatment strategies are needed. There are a number of novel therapies in development tailored to specific somatic mutations in the tumor.
Source: National Cancer Institute, 2014
Breast cancer is a malignant tumor that usually forms in the glands that make milk (lobules) and the tubes (ducts) that carry milk to the nipple. This year about 231,8400 women (and 2,000 men) in the U.S. will be told by a doctor that they have breast cancer. Half of these people will be at least 61 years old. However, more than 10 times as many women, about 2.7 million, remain alive today after having been diagnosed with breast cancer.

Breast cancer is not one disease and is currently classified into 3 subtypes based on the receptors present on the surface of the cancer cell. If the tumor is positive for estrogen and/or progesterone receptors, it is called "hormone receptor breast cancer". In that case, drugs that block the hormones, such as tamoxifen or aromatase inhibitors, might work best initially. If the tumor is positive for another type of receptor, called HER2 (or ERBB2), it is called "HER2 positive breast cancer", and certain targeted therapies that block HER2, such as the medications trastuzumab (Herceptin), pertuzumab (perjeta), T-DM1 (Kadcyla), and lapatanib (Tykerb) might work best and are recommended by the FDA. If the tumor is negative for HER2, estrogen, and progesterone receptors, it is called "triple negative breast cancer".

Over time, breast cancer (and other tumors) can spread from the site where it started (the primary tumor) in 3 ways. First, breast cancer cells can invade the normal tissue surrounding the tumor. Second, breast cancer cells can enter the lymph system and travel through lymph vessels to distant parts of the body. Third, the breast cancer cells can get into the blood stream and travel to other places in the body. In these distant places, the breast cancer cells cause secondary (metastatic) tumors to grow. The main sites where breast cancer spreads are the lungs, liver and bones. There is a lot of ongoing research to identify other receptors and mutations that are actionable through treatment using appropriate new targeted therapies that could be developed against the cancer.

Source: National Cancer Institute, 2015
Breast cancer is the most common non-cutaneous cancer among women in the United States. This year about 231,840 women (and 2,000 men) in the U.S. will be told by a doctor that they have breast cancer. Half of these people will be at least 61 years old. However, more than 10 times as many women, about 2.7 million, remain alive today after having been diagnosed with breast cancer.

Germline mutations in either the BRCA1 or BRCA2 gene confer an increased risk of breast and/or ovarian cancer. In addition, mutation carriers may be at increased risk of other primary cancers. Genetic testing is available to detect mutations in members of high-risk families. Such individuals should first be referred for counseling. Breast cancer is commonly treated by various combinations of surgery, radiation therapy, chemotherapy and hormone therapy.

Over the past years, significant major strides in understanding the biology of breast cancer have translated into actionable targeted therapies. For metastatic hormone receptor positive breast cancer, FDA approved therapies include tamoxifen, a selective estrogen modulator, aromatase inhibitors including exemestane, letrozole, and anastrozole, fulvestrant, a selective estrogen receptor blocker, and more recently everoliumus, a mTOR inhibitor, in combination with exemestane.

Despite significant improvements in the treatment of breast tumors, novel therapies and treatment strategies are needed. There are a number of novel therapies in development tailored to specific somatic mutations in the tumor.
Source: National Cancer Institute, 2014
Expand Collapse TP53  - General Description
CLICK IMAGE FOR MORE INFORMATION
The p53 (TP53) gene produces a protein, P53 which has many complex functions within the cell. It has been called the “guardian of the genome” for reasons that have to do with these complex functions. Normal, non-cancerous cells have tightly regulated pathways that control cell growth, mediating cessation of growth or even cell death when circumstances warrant it. P53 is at the center of these pathways, acting as a “tumor suppressor” in responding to circumstances in the cell that require a cessation of growth. Perhaps for this reason, P53 is one of the most commonly mutated genes across all cancer types.

P53 itself regulates the expression of several genes that are involved in growth arrest or “cell cycle arrest”. Growth arrest is important for stopping the cell from normal growth and cell division so that if, for instance, there has been damage to the DNA from UV irradiation or some other insult causing DNA damage, the cessation of the cell cycle allows DNA repair to take place before the cell resumes growth. If the damage to the DNA is too extensive to repair, or if other factors such as oncogenic stress impact the cell, P53 then has roles in other processes that are part of the cell’s repertoire of responses. These include processes such as apoptosis (programmed cell death), senescence (irreversible cell cycle arrest), autophagy (regulated destruction of selected proteins within the cell, leading to cell death), and some important metabolic changes in the cell (see graphic above, adapted with permission).

P53 is itself acted upon by proteins in the cell that detect DNA damage or oncogenic stress (see graphic depicting P53 at the center of a number of cellular responses). In the case of DNA damage to the cell, P53 is acted upon by a protein called ATM and another designated CHK2 (see glossary for more information). These proteins activate P53 to regulate the changes that will cause growth arrest. Interestingly, these two genes themselves are found to be mutated and have altered function in certain cancers. The fact that both P53 and the genes that trigger P53’s response and initiation of growth arrest are mutated in some cancers highlights the importance of P53 to normal cell growth. P53 is found to be mutated in over half of cancers studied, including ovarian cancer, colon and esophageal cancer, and many other types of cancer. Because p53 plays so many complex roles in the cell, we do not depict it in a simple graphic as we have with other proteins on this web site in which genetic alterations have been found in specific tumors that lead to dysregulation of these proteins. Rather, P53 as a negative regulator of cell growth under important circumstances plays this role at the center of a complex network of pathways within the cell. Many of the proteins involved in the pathways that regulate P53 and its responses are also found to be genetically altered in some cancers.

As we have seen, the P53 protein has many functions in the cell, and because of these many roles, its location in the nucleus or cytoplasm varies, depending on the function and when it exerts its effect during the cell cycle. One important protein that regulates P53 is called HDM2/MDM2, depicted in the graphic above. The HDM2/MDM2 protein contains a p53 binding domain, and once bound to p53, it inhibits the activation of the P53 protein, and thereby prevents P53 from regulating growth arrest, even when there is damage to the DNA. Some cancers have been found to overexpress HDM2/MDM2, meaning there is an excess of the protein which binds to P53, preventing it from exerting its important role in regulating growth arrest. Cell division that occurs despite damage to the DNA can lead to cancer. Interestingly, those cancers that have been found to over-express HDM2/MDM2 typically are not found to have p53 mutations. This provides scientists with evidence that by whatever means, either through increasing the amount of the P53 inhibitor HDM2/MDM2, or, through mutations in P53 that prevent the normal activities of the protein, the normal function of P53 is important in preventing cancer. MDM2 was named after its discovery in studies on laboratory mice. The human version of the gene is designated HumanDM2, or HDM2. Genetic alterations leading to over-expression of MDM2 are observed most commonly in sarcomas, but have also been observed in endometrial cancer, colon cancer, and stomach cancer.

Source: Molecular Genetics of Cancer, Second Edition
Chapter No. 2, Section No. 12
Leif W. Ellisen, MD, PhD
The p53 (TP53) gene produces a protein, P53 which has many complex functions within the cell. It has been called the “guardian of the genome” for reasons that have to do with these complex functions. Normal, non-cancerous cells have tightly regulated pathways that control cell growth, mediating cessation of growth or even cell death when circumstances warrant it. P53 is at the center of these pathways, acting as a “tumor suppressor” in responding to circumstances in the cell that require a cessation of growth. Perhaps for this reason, P53 is one of the most commonly mutated genes across all cancer types.

P53 itself regulates the expression of several genes that are involved in growth arrest or “cell cycle arrest”. Growth arrest is important for stopping the cell from normal growth and cell division so that if, for instance, there has been damage to the DNA from UV irradiation or some other insult causing DNA damage, the cessation of the cell cycle allows DNA repair to take place before the cell resumes growth. If the damage to the DNA is too extensive to repair, or if other factors such as oncogenic stress impact the cell, P53 then has roles in other processes that are part of the cell’s repertoire of responses. These include processes such as apoptosis (programmed cell death), senescence (irreversible cell cycle arrest), autophagy (regulated destruction of selected proteins within the cell, leading to cell death), and some important metabolic changes in the cell (see graphic above, adapted with permission).

P53 is itself acted upon by proteins in the cell that detect DNA damage or oncogenic stress (see graphic depicting P53 at the center of a number of cellular responses). In the case of DNA damage to the cell, P53 is acted upon by a protein called ATM and another designated CHK2 (see glossary for more information). These proteins activate P53 to regulate the changes that will cause growth arrest. Interestingly, these two genes themselves are found to be mutated and have altered function in certain cancers. The fact that both P53 and the genes that trigger P53’s response and initiation of growth arrest are mutated in some cancers highlights the importance of P53 to normal cell growth. P53 is found to be mutated in over half of cancers studied, including ovarian cancer, colon and esophageal cancer, and many other types of cancer. Because p53 plays so many complex roles in the cell, we do not depict it in a simple graphic as we have with other proteins on this web site in which genetic alterations have been found in specific tumors that lead to dysregulation of these proteins. Rather, P53 as a negative regulator of cell growth under important circumstances plays this role at the center of a complex network of pathways within the cell. Many of the proteins involved in the pathways that regulate P53 and its responses are also found to be genetically altered in some cancers.

As we have seen, the P53 protein has many functions in the cell, and because of these many roles, its location in the nucleus or cytoplasm varies, depending on the function and when it exerts its effect during the cell cycle. One important protein that regulates P53 is called HDM2/MDM2, depicted in the graphic above. The HDM2/MDM2 protein contains a p53 binding domain, and once bound to p53, it inhibits the activation of the P53 protein, and thereby prevents P53 from regulating growth arrest, even when there is damage to the DNA. Some cancers have been found to overexpress HDM2/MDM2, meaning there is an excess of the protein which binds to P53, preventing it from exerting its important role in regulating growth arrest. Cell division that occurs despite damage to the DNA can lead to cancer. Interestingly, those cancers that have been found to over-express HDM2/MDM2 typically are not found to have p53 mutations. This provides scientists with evidence that by whatever means, either through increasing the amount of the P53 inhibitor HDM2/MDM2, or, through mutations in P53 that prevent the normal activities of the protein, the normal function of P53 is important in preventing cancer. MDM2 was named after its discovery in studies on laboratory mice. The human version of the gene is designated HumanDM2, or HDM2. Genetic alterations leading to over-expression of MDM2 are observed most commonly in sarcomas, but have also been observed in endometrial cancer, colon cancer, and stomach cancer.

Source: Molecular Genetics of Cancer, Second Edition
Chapter No. 2, Section No. 12
Leif W. Ellisen, MD, PhD
Expand Collapse All Mutations  in TP53
TP53 Mutations that are associated with many cancer types result in the loss of function of the P53 proteins' tumor suppressor activity. Mutations in P53 that have been studied in tumors prevent P53 from acting to stop growth, or in other words, to cause cell cycle arrest. Cell cycle arrest mediated by P53 is necessary to give cells time to repair damaged DNA. P53 is also involved in other functions in the cellular repertoire to cause cells that have suffered too much damage to repair to undergo appoptosis or autophagy leading to deliberate cell death. When P53 normal function is debilitated through genetic mutations, the development of cancer is more likely than in cells that have intact and fully functional P53.
TP53 Mutations that are associated with many cancer types result in the loss of function of the P53 proteins' tumor suppressor activity. Mutations in P53 that have been studied in tumors prevent P53 from acting to stop growth, or in other words, to cause cell cycle arrest. Cell cycle arrest mediated by P53 is necessary to give cells time to repair damaged DNA. P53 is also involved in other functions in the cellular repertoire to cause cells that have suffered too much damage to repair to undergo appoptosis or autophagy leading to deliberate cell death. When P53 normal function is debilitated through genetic mutations, the development of cancer is more likely than in cells that have intact and fully functional P53.

Our Breast Cancer Team

Share with your Physican

Print information for your Physician.

Print information

Your Matched Clinical Trials

Trial Matches: (D) - Disease, (G) - Gene, (M) - Mutation
Trial Status: Showing Results: 1-10 of 38 Per Page:
1234Next »
Protocol # Title Location Status Match
NCT01296555 A Dose Escalation Study Evaluating the Safety and Tolerability of GDC-0032 in Participants With Locally Advanced or Metastatic Solid Tumors or Non-Hodgkin's Lymphoma (NHL) and in Combination With Endocrine Therapy in Locally Advanced or Metastatic Hormone Receptor-Positive Breast Cancer A Dose Escalation Study Evaluating the Safety and Tolerability of GDC-0032 in Participants With Locally Advanced or Metastatic Solid Tumors or Non-Hodgkin's Lymphoma (NHL) and in Combination With Endocrine Therapy in Locally Advanced or Metastatic Hormone Receptor-Positive Breast Cancer MGH Open D
NCT02052778 A Dose Finding Study Followed by a Safety and Efficacy Study in Patients With Advanced Solid Tumors or Multiple Myeloma With FGF/FGFR-Related Abnormalities A Dose Finding Study Followed by a Safety and Efficacy Study in Patients With Advanced Solid Tumors or Multiple Myeloma With FGF/FGFR-Related Abnormalities MGH Open D
NCT01862081 A Dose-escalation Study to Assess the Safety, Tolerability, and Pharmacokinetics of GDC-0032 in Combination With Docetaxel or With Paclitaxel in Patients With HER2-negative Locally Recurrent or Metastatic Breast Cancer or Non-small Cell Lung Cancer A Dose-escalation Study to Assess the Safety, Tolerability, and Pharmacokinetics of GDC-0032 in Combination With Docetaxel or With Paclitaxel in Patients With HER2-negative Locally Recurrent or Metastatic Breast Cancer or Non-small Cell Lung Cancer MGH Open D
NCT02099058 A Phase 1/1b Study With ABBV-399, an Antibody Drug Conjugate, in Subjects With Advanced Solid Cancer Tumors A Phase 1/1b Study With ABBV-399, an Antibody Drug Conjugate, in Subjects With Advanced Solid Cancer Tumors MGH Open D
NCT02338349 A Phase I, Multicenter, Open-Label, Two-Part, Dose-escalation Study of RAD1901 in Postmenopausal Women With Advanced Estrogen Receptor Positive and HER2-Negative Breast Cancer A Phase I, Multicenter, Open-Label, Two-Part, Dose-escalation Study of RAD1901 in Postmenopausal Women With Advanced Estrogen Receptor Positive and HER2-Negative Breast Cancer MGH Open D
NCT02219724 A Phase I, Open-Label Study of MOXR0916 in Patients With Locally Advanced or Metastatic Solid Tumors A Phase I, Open-Label Study of MOXR0916 in Patients With Locally Advanced or Metastatic Solid Tumors MGH Open D
NCT01525589 A Phase II Clinical Trial of PM01183 in BRCA 1/2-Associated or Unselected Metastatic Breast Cancer A Phase II Clinical Trial of PM01183 in BRCA 1/2-Associated or Unselected Metastatic Breast Cancer MGH Open D
NCT02365662 A Study Evaluating Safety and Pharmacokinetics of ABBV-221 in Subjects With Advanced Solid Tumor Types Likely to Exhibit Elevated Levels of Epidermal Growth Factor Receptor A Study Evaluating Safety and Pharmacokinetics of ABBV-221 in Subjects With Advanced Solid Tumor Types Likely to Exhibit Elevated Levels of Epidermal Growth Factor Receptor MGH Open D
NCT02467361 A Study of BBI608 Administered in Combination With Immune Checkpoint Inhibitors in Adult Patients With Advanced Cancers A Study of BBI608 Administered in Combination With Immune Checkpoint Inhibitors in Adult Patients With Advanced Cancers MGH Open D
NCT01325441 A Study of BBI608 Administered With Paclitaxel in Adult Patients With Advanced Malignancies A Study of BBI608 Administered With Paclitaxel in Adult Patients With Advanced Malignancies MGH Open D
Trial Status: Showing Results: 1-10 of 38 Per Page:
1234Next »
Our Breast Cancer Team

Share with your Physican

Print information for your Physician.

Print information