Bladder Cancer, ATR

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Expand Collapse Bladder Cancer  - General Description This year about 74,000 people in the U.S. (76% of them men and half will be over the age of 73 years old) will be told by a doctor that they have cancer of the urinary bladder. With significant improvements in the treatment of this malignancy, about 550,000 of them remain alive today.

Bladder cancer begins in different types of cells found in the inner lining of the bladder, the flexible muscular organ that stores urine. Transitional cells, which stretch or shrink as the bladder fills or empties, account for 90% of bladder cancers in the United States. Less commonly (in 6-8% of U.S. bladder cancers), the cancer begins in squamous cells that may form in response to irritation or infection that has lasted a long time. Adenocarcinoma begins in cells that make mucous and accounts for only about 2% of U.S. bladder cancers. Adenocarcinoma of the bladder is also believed to be a result of long-lasting irritation or inflammation.

If the cancer stays in the lining of the bladder, it is called superficial bladder cancer. Sometimes, though, transitional cell cancer spreads through the lining and breaks into the muscular wall beneath it or spreads to nearby organs and lymph nodes. In this case it is known as invasive bladder cancer.

Bladder cancer (and other tumors) can spread (metastasize) from the place where it started (the primary tumor) in 3 ways. First, it can invade the normal tissue surrounding it. Second, bladder cancer cells can enter the lymph system and travel through lymph vessels to distant parts of the body. Third, the cancer cells can get into the blood stream and go to other places in the body. In these distant places, the bladder cancer cells cause secondary (metastatic) tumors to grow, in the bones, for example. To find out whether the cancer has entered the lymph system, a surgeon removes all or part of a lymph node and a pathologist inspects it under a microscope. Several kinds of imaging can also be performed to determine if bladder cancer has spread. These include CT scans, MRI, chest x-rays and bone scans.

Source: National Cancer Institute, 2012
This year about 74,000 people in the U.S. (76% of them men and half will be over the age of 73 years old) will be told by a doctor that they have cancer of the urinary bladder. With significant improvements in the treatment of this malignancy, about 550,000 of them remain alive today.

Bladder cancer begins in different types of cells found in the inner lining of the bladder, the flexible muscular organ that stores urine. Transitional cells, which stretch or shrink as the bladder fills or empties, account for 90% of bladder cancers in the United States. Less commonly (in 6-8% of U.S. bladder cancers), the cancer begins in squamous cells that may form in response to irritation or infection that has lasted a long time. Adenocarcinoma begins in cells that make mucous and accounts for only about 2% of U.S. bladder cancers. Adenocarcinoma of the bladder is also believed to be a result of long-lasting irritation or inflammation.

If the cancer stays in the lining of the bladder, it is called superficial bladder cancer. Sometimes, though, transitional cell cancer spreads through the lining and breaks into the muscular wall beneath it or spreads to nearby organs and lymph nodes. In this case it is known as invasive bladder cancer.

Bladder cancer (and other tumors) can spread (metastasize) from the place where it started (the primary tumor) in 3 ways. First, it can invade the normal tissue surrounding it. Second, bladder cancer cells can enter the lymph system and travel through lymph vessels to distant parts of the body. Third, the cancer cells can get into the blood stream and go to other places in the body. In these distant places, the bladder cancer cells cause secondary (metastatic) tumors to grow, in the bones, for example. To find out whether the cancer has entered the lymph system, a surgeon removes all or part of a lymph node and a pathologist inspects it under a microscope. Several kinds of imaging can also be performed to determine if bladder cancer has spread. These include CT scans, MRI, chest x-rays and bone scans.

Source: National Cancer Institute, 2012
This year about 74,000 people in the U.S. (76% of them men and half will be over the age of 73 years old) will be told by a doctor that they have cancer of the urinary bladder. With significant improvements in the treatment of this malignancy, about 550,000 of them remain alive today.

Bladder cancer begins in different types of cells found in the inner lining of the bladder, the flexible muscular organ that stores urine. Transitional cells, which stretch or shrink as the bladder fills or empties, account for 90% of bladder cancers in the United States. Less commonly (in 6-8% of U.S. bladder cancers), the cancer begins in squamous cells that may form in response to irritation or infection that has lasted a long time. Adenocarcinoma begins in cells that make mucous and accounts for only about 2% of U.S. bladder cancers. Adenocarcinoma of the bladder is also believed to be a result of long-lasting irritation or inflammation.

If the cancer stays in the lining of the bladder, it is called superficial bladder cancer. Sometimes, though, transitional cell cancer spreads through the lining and breaks into the muscular wall beneath it or spreads to nearby organs and lymph nodes. In this case it is known as invasive bladder cancer.

Bladder cancer (and other tumors) can spread (metastasize) from the place where it started (the primary tumor) in 3 ways. First, it can invade the normal tissue surrounding it. Second, bladder cancer cells can enter the lymph system and travel through lymph vessels to distant parts of the body. Third, the cancer cells can get into the blood stream and go to other places in the body. In these distant places, the bladder cancer cells cause secondary (metastatic) tumors to grow, in the bones, for example. To find out whether the cancer has entered the lymph system, a surgeon removes all or part of a lymph node and a pathologist inspects it under a microscope. Several kinds of imaging can also be performed to determine if bladder cancer has spread. These include CT scans, MRI, chest x-rays and bone scans.

Source: National Cancer Institute, 2012
This year about 74,000 people in the U.S. (76% of them men and half will be over the age of 73 years old) will be told by a doctor that they have cancer of the urinary bladder. With significant improvements in the treatment of this malignancy, about 550,000 of them remain alive today.

Bladder cancer begins in different types of cells found in the inner lining of the bladder, the flexible muscular organ that stores urine. Transitional cells, which stretch or shrink as the bladder fills or empties, account for 90% of bladder cancers in the United States. Less commonly (in 6-8% of U.S. bladder cancers), the cancer begins in squamous cells that may form in response to irritation or infection that has lasted a long time. Adenocarcinoma begins in cells that make mucous and accounts for only about 2% of U.S. bladder cancers. Adenocarcinoma of the bladder is also believed to be a result of long-lasting irritation or inflammation.

If the cancer stays in the lining of the bladder, it is called superficial bladder cancer. Sometimes, though, transitional cell cancer spreads through the lining and breaks into the muscular wall beneath it or spreads to nearby organs and lymph nodes. In this case it is known as invasive bladder cancer.

Bladder cancer (and other tumors) can spread (metastasize) from the place where it started (the primary tumor) in 3 ways. First, it can invade the normal tissue surrounding it. Second, bladder cancer cells can enter the lymph system and travel through lymph vessels to distant parts of the body. Third, the cancer cells can get into the blood stream and go to other places in the body. In these distant places, the bladder cancer cells cause secondary (metastatic) tumors to grow, in the bones, for example. To find out whether the cancer has entered the lymph system, a surgeon removes all or part of a lymph node and a pathologist inspects it under a microscope. Several kinds of imaging can also be performed to determine if bladder cancer has spread. These include CT scans, MRI, chest x-rays and bone scans.

Source: National Cancer Institute, 2012
Expand Collapse ATR  - General Description
CLICK IMAGE FOR MORE INFORMATION
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 ATR  in Bladder Cancer
Alterations in the gene encoding ATR are not found in bladder 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 bladder 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.

Expand Collapse No mutation selected
The mutation of a gene provides clinicians with a very detailed look at your cancer. Knowing this information could change the course of your care. To learn how you can find out more about genetic testing please visit http://www.massgeneral.org/cancer/news/faq.aspx or contact the Cancer Center.
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Your Matched Clinical Trials

Trial Matches: (D) - Disease, (G) - Gene
Trial Status: Showing Results: 1-10 of 19 Per Page:
12Next »
Protocol # Title Location Status Match
NCT02567409 Cisplatin and Gemcitabine Hydrochloride With or Without ATR Kinase Inhibitor VX-970 in Treating Patients With Metastatic Urothelial Cancer Cisplatin and Gemcitabine Hydrochloride With or Without ATR Kinase Inhibitor VX-970 in Treating Patients With Metastatic Urothelial Cancer MGH Open DG
NCT02897765 A Personal Cancer Vaccine (NEO-PV-01) w/ Nivolumab for Patients With Melanoma, Lung Cancer or Bladder Cancer A Personal Cancer Vaccine (NEO-PV-01) w/ Nivolumab for Patients With Melanoma, Lung Cancer or Bladder Cancer MGH Open D
NCT02450331 A Study of Atezolizumab Versus Observation as Adjuvant Therapy in Participants With High-Risk Muscle-Invasive Urothelial Carcinoma (UC) After Surgical Resection A Study of Atezolizumab Versus Observation as Adjuvant Therapy in Participants With High-Risk Muscle-Invasive Urothelial Carcinoma (UC) After Surgical Resection MGH Open D
NCT02603432 A Study Of Avelumab In Patients With Locally Advanced Or Metastatic Urothelial Cancer (JAVELIN Bladder 100) A Study Of Avelumab In Patients With Locally Advanced Or Metastatic Urothelial Cancer (JAVELIN Bladder 100) MGH Open D
NCT03219333 A Study of Enfortumab Vedotin for Patients With Locally Advanced or Metastatic Urothelial Bladder Cancer A Study of Enfortumab Vedotin for Patients With Locally Advanced or Metastatic Urothelial Bladder Cancer MGH Open D
NCT02052778 A Study of TAS-120 in Patients With Advanced Solid Tumors A Study of TAS-120 in Patients With Advanced Solid Tumors MGH Open D
NCT01948297 Debio 1347-101 Phase I Trial in Advanced Solid Tumours With Fibroblast Growth Factor Receptor (FGFR) Alterations Debio 1347-101 Phase I Trial in Advanced Solid Tumours With Fibroblast Growth Factor Receptor (FGFR) Alterations MGH Open D
NCT03330405 Javelin Parp Medley: Avelumab Plus Talazoparib In Locally Advanced Or Metastatic Solid Tumors Javelin Parp Medley: Avelumab Plus Talazoparib In Locally Advanced Or Metastatic Solid Tumors MGH Open D
NCT02989064 MAGE-A10ᶜ⁷⁹⁶T for Urothelial Cancer, Melanoma or Head and Neck Cancers MAGE-A10ᶜ⁷⁹⁶T for Urothelial Cancer, Melanoma or Head and Neck Cancers MGH Open D
NCT01953926 Neratinib HER Mutation Basket Study (SUMMIT) Neratinib HER Mutation Basket Study (SUMMIT) MGH Open D
Trial Status: Showing Results: 1-10 of 19 Per Page:
12Next »
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