Breast Cancer, ATR, no-mutation in ATR

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Expand Collapse Breast Cancer  - General Description Breast cancer is the most common non-cutaneous cancer among women in the United States. This year about 252,710 women in the U.S. will be told by a doctor that they have breast cancer. Half of these people will be at least 62 years old. However, an estimated 3,327,552 women are living with female breast cancer in the United States following treatment.

Germline (inherited) mutations in either the BRCA1 or BRCA2 gene confer an increased risk of breast and/or ovarian cancer to women. In addition, women and men carrying BRCA1 or BRCA2 mutations are at increased risk of developing other primary cancers. Genetic testing is available at the MGH genetics lab to detect mutations in members of high-risk families. Such individuals should also be referred for genetic counseling to obtain more information about the implications of inherited BRCA1 and BRCA2 mutations. Innovative treatments are available for patients with inherited BRCA1 or BRCA2 mutations at the MGH Cancer Center. There is also a large portfolio of clinical trials testing the newest treatments at the MGH Cancer Center.

Despite significant improvements in the treatment of breast tumors, new therapies and treatment strategies are needed to improve outcomes for breast cancer patients. There are a number of novel targeted therapies as well as new immuno-therapies being used that are tailored to individual patient mutations at the MGH Cancer Center.

Source: National Cancer Institute, 2017
Breast cancer is the most common non-cutaneous cancer among women in the United States. This year about 252,710 women in the U.S. will be told by a doctor that they have breast cancer. Half of these people will be at least 62 years old. However, an estimated 3,327,552 women are living with female breast cancer in the United States following treatment.

Germline (inherited) mutations in either the BRCA1 or BRCA2 gene confer an increased risk of breast and/or ovarian cancer to women. In addition, women and men carrying BRCA1 or BRCA2 mutations are at increased risk of developing other primary cancers. Genetic testing is available at the MGH genetics lab to detect mutations in members of high-risk families. Such individuals should also be referred for genetic counseling to obtain more information about the implications of inherited BRCA1 and BRCA2 mutations. Innovative treatments are available for patients with inherited BRCA1 or BRCA2 mutations at the MGH Cancer Center. There is also a large portfolio of clinical trials testing the newest treatments at the MGH Cancer Center.

Despite significant improvements in the treatment of breast tumors, new therapies and treatment strategies are needed to improve outcomes for breast cancer patients. There are a number of novel targeted therapies as well as new immuno-therapies being used that are tailored to individual patient mutations at the MGH Cancer Center.

Source: National Cancer Institute, 2017
Breast cancer is the most common non-cutaneous cancer among women in the United States. This year about 252,710 women in the U.S. will be told by a doctor that they have breast cancer. Half of these people will be at least 62 years old. However, an estimated 3,327,552 women are living with female breast cancer in the United States following treatment.

Germline (inherited) mutations in either the BRCA1 or BRCA2 gene confer an increased risk of breast and/or ovarian cancer to women. In addition, women and men carrying BRCA1 or BRCA2 mutations are at increased risk of developing other primary cancers. Genetic testing is available at the MGH genetics lab to detect mutations in members of high-risk families. Such individuals should also be referred for genetic counseling to obtain more information about the implications of inherited BRCA1 and BRCA2 mutations. Innovative treatments are available for patients with inherited BRCA1 or BRCA2 mutations at the MGH Cancer Center. There is also a large portfolio of clinical trials testing the newest treatments at the MGH Cancer Center.

Despite significant improvements in the treatment of breast tumors, new therapies and treatment strategies are needed to improve outcomes for breast cancer patients. There are a number of novel targeted therapies as well as new immuno-therapies being used that are tailored to individual patient mutations at the MGH Cancer Center.

Source: National Cancer Institute, 2017
Breast cancer is the most common non-cutaneous cancer among women in the United States. This year about 252,710 women in the U.S. will be told by a doctor that they have breast cancer. Half of these people will be at least 62 years old. However, an estimated 3,327,552 women are living with female breast cancer in the United States following treatment.

Germline (inherited) mutations in either the BRCA1 or BRCA2 gene confer an increased risk of breast and/or ovarian cancer to women. In addition, women and men carrying BRCA1 or BRCA2 mutations are at increased risk of developing other primary cancers. Genetic testing is available at the MGH genetics lab to detect mutations in members of high-risk families. Such individuals should also be referred for genetic counseling to obtain more information about the implications of inherited BRCA1 and BRCA2 mutations. Innovative treatments are available for patients with inherited BRCA1 or BRCA2 mutations at the MGH Cancer Center. There is also a large portfolio of clinical trials testing the newest treatments at the MGH Cancer Center.

Despite significant improvements in the treatment of breast tumors, new therapies and treatment strategies are needed to improve outcomes for breast cancer patients. There are a number of novel targeted therapies as well as new immuno-therapies being used that are tailored to individual patient mutations at the MGH Cancer Center.

Source: National Cancer Institute, 2017
Expand Collapse ATR  - General Description
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The protein encoded by ATR is a serine/threonine kinase and DNA damage sensor, activating cell cycle checkpoint signaling and causing a pause in the cell cycle following DNA replication stress or damage. The activated protein can phosphorylate and activate several important proteins that are involved in the inhibition of DNA replication and cell division, which are critical for DNA repair.

The maintenance of intact, correctly sequenced DNA is vital to the life of a cell. If there are mistakes made in replicating DNA before cell division, subsequent daughter cells will have inaccurate or damaged DNA, and may either die or carry mutations that can contribute to the development of cancer. For this reason, cells have evolved multiple pathways to repair mistakes in-or damage to- DNA. The specific repair pathway used by the cell depends on the type of DNA damage that has occurred. The types of DNA repair that we are focusing on relate directly to cancer. These involve a break in BOTH strands of DNA, which can be the result of ionizing radiation or other DNA damaging agents. This type of DNA damage is called Double Strand Breaks (DSB's). There are two main pathways used by cells to repair DSB's in DNA, one is Homologous Recombination (HR), the other is Non-Homologous End Joining (NHEJ). This page of our website focuses on the HR pathway (there is a separate web page for NHEJ repair if you select PKcs from the gene list when you sign on to this page).

Many proteins are involved in the complex HR pathway to repair DSB's in DNA. There is a graphic above that depicts the HR pathway (if you click on the graphic, it will enlarge and become a bit easier to follow). While complicated, the DSB at the top right of the graphic is acted upon by a series of proteins in the circle of steps shown that ultimately lead to the complete and accurate repair of the DSB in the DNA.

Some of the proteins involved in the HR DSB repair pathway are MRE11, NBS1, RAD50. These three proteins make up the MRN complex. This complex detects DSB's in the DNA. Once the DSB is found by the MRN complex, the MRN complex functions with BRCA1 and CtIP to resect the DSB’s to form single stranded DNA “tails”. Meanwhile, DSB's also activate the ATM protein, which in turn acts upon CHK2 to activate it, as well as directly activating the tumor suppressor TP53. TP53 can cause cell cycle delay, giving the cell time to repair DNA breaks or mistakes before the cell cycle leading to division resumes. In the next step, RPA binds to the single stranded DNA "tails" that have been created by BRCA1 and CtIP in conjunction with the MRN. The binding of RPA activates another protein called ATR. ATR has many important functions, including activating CHK1, which can cause cell cycle delay giving cells time to repair DNA. ATR also regulates BRCA1 which recruits a bound group of proteins including PALB2/BRCA2/RAD51. In the next step, RAD51 displaces the RPA that is on the single stranded DNA, with the involvement of BRCA2/PALB2 and RAD51c. BRCA1/BARD1 helps RAD51 coated single stranded DNA invade double stranded DNA with homologous sequences to form a DNA repair loop. With the help of DNA polymerases, the repair loop creates the opportunity to use the intact homologous DNA as a template to correctly repair DSB’s. Enzymes called ligases reconnect the ends of the DNA, leading to complete and accurate repair of the DSB in DNA.

After studying familial cancer syndromes, germline or inherited BRCA1 and BRCA2 were identified a while ago as proteins that when altered by mutation, cause certain cancers. Some BRCA1 and BRCA2 genes become mutated somatically, meaning in a non-inherited way. When either gene is mutated, the resulting protein cannot perform its role in DNA repair correctly. This turns out to be true for other proteins in the HR pathway as well. Recently, scientists have found mutations in many of the other genes that encode the proteins involved in the HR pathway. Mutations in HR pathway members include MRE11, NBS1, RAD50, ATM, CHK2, BRCA1, PALB2, RAD51, BRCA2, BARD1, and RAD51c (these are depicted in red in the above graphic). This remarkable number of mutations in proteins involved in the DNA repair pathway found in cancer highlights how important the HR DSB DNA repair pathway is in cells. The mutations in HR pathway proteins result in proteins that do not function properly in their role in DNA repair. Without proper function of the proteins involved in DNA repair, DNA mistakes or breaks are not properly repaired, and the damaged DNA contributes to the development of cancer.

ATR is only rarely mutated in cancer, however, the frequent mutations in ATM result in cells that are completely reliant on the ATR pathway to repair DSB's in the DNA. This has therapeutic implications for treatment of tumors that have mutations in the HR DNA repair pathway.

Testing for mutations in the many genes/proteins involved in DNA repair discussed above is available in the MGH genetics lab. Treatment as well as clinical trials studying new drugs that target defects in these proteins-including ATR- are available at the MGH Cancer Center.

The protein encoded by ATR is a serine/threonine kinase and DNA damage sensor, activating cell cycle checkpoint signaling and causing a pause in the cell cycle following DNA replication stress or damage. The activated protein can phosphorylate and activate several important proteins that are involved in the inhibition of DNA replication and cell division, which are critical for DNA repair.

The maintenance of intact, correctly sequenced DNA is vital to the life of a cell. If there are mistakes made in replicating DNA before cell division, subsequent daughter cells will have inaccurate or damaged DNA, and may either die or carry mutations that can contribute to the development of cancer. For this reason, cells have evolved multiple pathways to repair mistakes in-or damage to- DNA. The specific repair pathway used by the cell depends on the type of DNA damage that has occurred. The types of DNA repair that we are focusing on relate directly to cancer. These involve a break in BOTH strands of DNA, which can be the result of ionizing radiation or other DNA damaging agents. This type of DNA damage is called Double Strand Breaks (DSB's). There are two main pathways used by cells to repair DSB's in DNA, one is Homologous Recombination (HR), the other is Non-Homologous End Joining (NHEJ). This page of our website focuses on the HR pathway (there is a separate web page for NHEJ repair if you select PKcs from the gene list when you sign on to this page).

Many proteins are involved in the complex HR pathway to repair DSB's in DNA. There is a graphic above that depicts the HR pathway (if you click on the graphic, it will enlarge and become a bit easier to follow). While complicated, the DSB at the top right of the graphic is acted upon by a series of proteins in the circle of steps shown that ultimately lead to the complete and accurate repair of the DSB in the DNA.

Some of the proteins involved in the HR DSB repair pathway are MRE11, NBS1, RAD50. These three proteins make up the MRN complex. This complex detects DSB's in the DNA. Once the DSB is found by the MRN complex, the MRN complex functions with BRCA1 and CtIP to resect the DSB’s to form single stranded DNA “tails”. Meanwhile, DSB's also activate the ATM protein, which in turn acts upon CHK2 to activate it, as well as directly activating the tumor suppressor TP53. TP53 can cause cell cycle delay, giving the cell time to repair DNA breaks or mistakes before the cell cycle leading to division resumes. In the next step, RPA binds to the single stranded DNA "tails" that have been created by BRCA1 and CtIP in conjunction with the MRN. The binding of RPA activates another protein called ATR. ATR has many important functions, including activating CHK1, which can cause cell cycle delay giving cells time to repair DNA. ATR also regulates BRCA1 which recruits a bound group of proteins including PALB2/BRCA2/RAD51. In the next step, RAD51 displaces the RPA that is on the single stranded DNA, with the involvement of BRCA2/PALB2 and RAD51c. BRCA1/BARD1 helps RAD51 coated single stranded DNA invade double stranded DNA with homologous sequences to form a DNA repair loop. With the help of DNA polymerases, the repair loop creates the opportunity to use the intact homologous DNA as a template to correctly repair DSB’s. Enzymes called ligases reconnect the ends of the DNA, leading to complete and accurate repair of the DSB in DNA.

After studying familial cancer syndromes, germline or inherited BRCA1 and BRCA2 were identified a while ago as proteins that when altered by mutation, cause certain cancers. Some BRCA1 and BRCA2 genes become mutated somatically, meaning in a non-inherited way. When either gene is mutated, the resulting protein cannot perform its role in DNA repair correctly. This turns out to be true for other proteins in the HR pathway as well. Recently, scientists have found mutations in many of the other genes that encode the proteins involved in the HR pathway. Mutations in HR pathway members include MRE11, NBS1, RAD50, ATM, CHK2, BRCA1, PALB2, RAD51, BRCA2, BARD1, and RAD51c (these are depicted in red in the above graphic). This remarkable number of mutations in proteins involved in the DNA repair pathway found in cancer highlights how important the HR DSB DNA repair pathway is in cells. The mutations in HR pathway proteins result in proteins that do not function properly in their role in DNA repair. Without proper function of the proteins involved in DNA repair, DNA mistakes or breaks are not properly repaired, and the damaged DNA contributes to the development of cancer.

ATR is only rarely mutated in cancer, however, the frequent mutations in ATM result in cells that are completely reliant on the ATR pathway to repair DSB's in the DNA. This has therapeutic implications for treatment of tumors that have mutations in the HR DNA repair pathway.

Testing for mutations in the many genes/proteins involved in DNA repair discussed above is available in the MGH genetics lab. Treatment as well as clinical trials studying new drugs that target defects in these proteins-including ATR- are available at the MGH Cancer Center.



PubMed ID's
27617969, 24003211, PMC2988877
Expand Collapse no-mutation in ATR  in ATR
Mutations in the ATR gene are extremely rare in cancers. In fact, the ATR protein and its role in causing cell cycle delay through activating the protein CHK1 is a key pathway. Cell cycle delay induced by CHK1 gives the cell time to repair DSB's in the DNA, thereby acting as a tumor suppressor. When other proteins in the HR DNA pathway are mutated (see red proteins in the graphic above), ATR is the only option for DNA repair left to cells. This is why ATR inhibitors and other therapies can be effective treatments inducing death to tumor-cells.
Mutations in the ATR gene are extremely rare in cancers. In fact, the ATR protein and its role in causing cell cycle delay through activating the protein CHK1 is a key pathway. Cell cycle delay induced by CHK1 gives the cell time to repair DSB's in the DNA, thereby acting as a tumor suppressor. When other proteins in the HR DNA pathway are mutated (see red proteins in the graphic above), ATR is the only option for DNA repair left to cells. This is why ATR inhibitors and other therapies can be effective treatments inducing death to tumor-cells.

Alterations in the gene encoding ATR are not found in breast cancers. ATR is an important protein in the DNA repair pathway. ATR controls a signaling pathway in the cell by activating CHK1, which causes a delay in the cell cycle (see graphic above). Without this delay, cells would not have time to repair broken or damaged DNA. The accumulation of damaged DNA in the cell can lead to cancer.

ATR has become an important protein to inhibit with drugs in cancer. Cancer cells often have genetic alterations in other proteins in the DNA repair pathway (see red proteins in graphic above). If the ATM protein is mutated and unable to cause cell cycle arrest for DNA repair, then ATR is the only option for cancer cells to use to delay the cell cycle and repair DNA. Drugs targeting ATR block this pathway, leaving cancer cells no way to pause the cell cycle to achieve DNA repair. The tumor cells die as the result of accumulated damaged or broken DNA.

Alterations in the gene encoding ATR are not found in breast cancers. ATR is an important protein in the DNA repair pathway. ATR controls a signaling pathway in the cell by activating CHK1, which causes a delay in the cell cycle (see graphic above). Without this delay, cells would not have time to repair broken or damaged DNA. The accumulation of damaged DNA in the cell can lead to cancer.

ATR has become an important protein to inhibit with drugs in cancer. Cancer cells often have genetic alterations in other proteins in the DNA repair pathway (see red proteins in graphic above). If the ATM protein is mutated and unable to cause cell cycle arrest for DNA repair, then ATR is the only option for cancer cells to use to delay the cell cycle and repair DNA. Drugs targeting ATR block this pathway, leaving cancer cells no way to pause the cell cycle to achieve DNA repair. The tumor cells die as the result of accumulated damaged or broken DNA.

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Your Matched Clinical Trials

Trial Matches: (D) - Disease, (G) - Gene, (M) - Mutation
Trial Status: Showing Results: 1-10 of 53 Per Page:
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Protocol # Title Location Status Match
NCT02715284 A Phase 1 Dose Escalation and Cohort Expansion Study of TSR-042, an Anti-PD-1 Monoclonal Antibody, in Patients With Advanced Solid Tumors A Phase 1 Dose Escalation and Cohort Expansion Study of TSR-042, an Anti-PD-1 Monoclonal Antibody, in Patients With Advanced Solid Tumors MGH Open D
NCT03134638 A Phase 1 Study of SY-1365 in Adult Patients With Advanced Solid Tumors A Phase 1 Study of SY-1365 in Adult Patients With Advanced Solid Tumors MGH Open D
NCT03088527 A Phase 1, First-in-Human Study of RAD140 in Postmenopausal Women With Hormone Receptor Positive Breast Cancer A Phase 1, First-in-Human Study of RAD140 in Postmenopausal Women With Hormone Receptor Positive Breast Cancer MGH Open D
NCT02979899 A RANDOMIZED PHASE 3 TRIAL OF TRC105 AND PAZOPANIB VERSUS PAZOPANIB ALONE IN PATIENTS WITH ADVANCED ANGIOSARCOMA A RANDOMIZED PHASE 3 TRIAL OF TRC105 AND PAZOPANIB VERSUS PAZOPANIB ALONE IN PATIENTS WITH ADVANCED ANGIOSARCOMA MGH Open D
NCT03051659 A Randomized Phase II Study Of Eribulin Mesylate With or Without Pembrolizumab For Metastatic Hormone Receptor Positive Breast Cancer A Randomized Phase II Study Of Eribulin Mesylate With or Without Pembrolizumab For Metastatic Hormone Receptor Positive Breast Cancer MGH Open D
NCT03095352 A Randomized Phase II Study of Pembrolizumab, an Anti-PD (Programmed Cell Death)-1 Antibody, in Combination With Carboplatin Compared to Carboplatin Alone in Breast Cancer Patients With Chest Wall Disease A Randomized Phase II Study of Pembrolizumab, an Anti-PD (Programmed Cell Death)-1 Antibody, in Combination With Carboplatin Compared to Carboplatin Alone in Breast Cancer Patients With Chest Wall Disease MGH Open D
NCT02099058 A Study Evaluating the Safety, Pharmacokinetics (PK), and Preliminary Efficacy of ABBV-399 in Subjects With Advanced Solid Tumors. A Study Evaluating the Safety, Pharmacokinetics (PK), and Preliminary Efficacy of ABBV-399 in Subjects With Advanced Solid Tumors. MGH Open D
NCT03148418 A Study in Participants Previously Enrolled in a Genentech− and/or F. Hoffmann-La Roche Ltd-Sponsored Atezolizumab Study (IMbrella A) A Study in Participants Previously Enrolled in a Genentech− and/or F. Hoffmann-La Roche Ltd-Sponsored Atezolizumab Study (IMbrella A) 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
NCT03332797 A Study of GDC-9545 Alone or in Combination With Palbociclib and/or Luteinizing Hormone-Releasing Hormone (LHRH) Agonist in Locally Advanced or Metastatic Estrogen Receptor-Positive Breast Cancer A Study of GDC-9545 Alone or in Combination With Palbociclib and/or Luteinizing Hormone-Releasing Hormone (LHRH) Agonist in Locally Advanced or Metastatic Estrogen Receptor-Positive Breast Cancer MGH Open D
Trial Status: Showing Results: 1-10 of 53 Per Page:
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