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Expand Collapse Colorectal Cancer  - General Description A cancer that begins in the colon is often called colon cancer and a cancer that begins in the rectum is often called rectal cancer, but sometimes the term colorectal cancer is used for a cancer that begins in either place. This year about 132,700 people in the U.S. will be diagnosed with cancer of the colon or rectum. However, nearly 1.1 million remain alive today after having been diagnosed with colorectal cancer.

The colon and rectum are parts of the large intestine. In the colon, which accounts for most of the length of the large intestine, water and nutrients are extracted from partly-digested food before the food is turned into waste. The waste then enters the rectum before being pushed out of the body, leaving via the short anal canal and the anus (cancers also develop in the anus and anal canal, but they aren't classified as colorectal cancers). Most colon cancers and rectal cancers are adenocarcinomas, tumors that begin in gland-like cells lining the colon or rectum. Other types of cancerous tissues account for only 2% to 5% of colorectal cancers.

Colorectal 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, 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 bloodstream and go to other places in the body. In these distant places, the colon/rectal cancer cells cause secondary tumors to grow. The main sites to which colorectal cancer spreads are the liver, lungs and peritoneum. To find out whether the cancer has entered the lymph system, a surgeon removes all or part of a node near the primary tumor and a pathologist examines it to see if cancer cells are present. Several kinds of imaging also can be performed to determine if the cancer has spread. These include chest x-rays, MRI, CT scans and PET scans.

The FDA has approved several targeted therapies for treatment of patients with metastatic colorectal cancer. These include bevacizumab (Avastin), cetuximab (Erbitux), panitumumab (Vectibix) and ziv-afibercept (Zaltrap).

Despite significant improvements in the treatment of colorectal cancers, novel therapies and treatment strategies are needed.

Source: National Cancer Institute, 2015
The prognosis of patients with colon cancer is clearly related to the degree of tumor penetration through the bowel wall, the presence or absence of nodal involvement, and the presence or absence of distant metastases. These three characteristics form the basis for all staging systems developed for this disease. Bowel obstruction and bowel perforation are indicators of poor prognosis. Elevated pretreatment serum levels of carcinoembryonic antigen (CEA) have a negative prognostic significance. The American Joint Committee on Cancer and a National Cancer Institute-sponsored panel recommended that at least 12 lymph nodes be examined in patients with colon and rectal cancer to confirm the absence of nodal involvement by tumor. This recommendation takes into consideration that the number of lymph nodes examined is a reflection of the aggressiveness of lymphovascular mesenteric dissection at the time of surgical resection and the pathologic identification of nodes in the specimen. Retrospective studies demonstrated that the number of lymph nodes examined in colon and rectal surgery may be associated with patient outcome.

Many other prognostic markers have been evaluated retrospectively for patients with colon cancer, though most have not been prospectively validated (including allelic loss of chromosome 18q or thymidylate synthase expression). Microsatellite instability, also associated with hereditary nonpolyposis colon cancer (HNPCC), has been associated with improved survival (independent of tumor stage) in a population-based series of 607 patients younger than 50 years of age with colorectal cancer. Treatment decisions generally depend on factors such as physician/patient preferences and the stage of the disease, rather than the age of the patient. Racial differences in overall survival after adjuvant therapy have been observed (although not in disease-free survival), suggesting that comorbid conditions play a role in survival outcome in different patient populations.

Source: National Cancer Institute, 2012
A cancer that begins in the colon is often called colon cancer and a cancer that begins in the rectum is often called rectal cancer, but sometimes the term colorectal cancer is used for a cancer that begins in either place. This year about 132,700 people in the U.S. will be diagnosed with cancer of the colon or rectum. However, nearly 1.1 million remain alive today after having been diagnosed with colorectal cancer.

The colon and rectum are parts of the large intestine. In the colon, which accounts for most of the length of the large intestine, water and nutrients are extracted from partly-digested food before the food is turned into waste. The waste then enters the rectum before being pushed out of the body, leaving via the short anal canal and the anus (cancers also develop in the anus and anal canal, but they aren't classified as colorectal cancers). Most colon cancers and rectal cancers are adenocarcinomas, tumors that begin in gland-like cells lining the colon or rectum. Other types of cancerous tissues account for only 2% to 5% of colorectal cancers.

Colorectal 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, 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 bloodstream and go to other places in the body. In these distant places, the colon/rectal cancer cells cause secondary tumors to grow. The main sites to which colorectal cancer spreads are the liver, lungs and peritoneum. To find out whether the cancer has entered the lymph system, a surgeon removes all or part of a node near the primary tumor and a pathologist examines it to see if cancer cells are present. Several kinds of imaging also can be performed to determine if the cancer has spread. These include chest x-rays, MRI, CT scans and PET scans.

The FDA has approved several targeted therapies for treatment of patients with metastatic colorectal cancer. These include bevacizumab (Avastin), cetuximab (Erbitux), panitumumab (Vectibix) and ziv-afibercept (Zaltrap).

Despite significant improvements in the treatment of colorectal cancers, novel therapies and treatment strategies are needed.

Source: National Cancer Institute, 2015
The prognosis of patients with colon cancer is clearly related to the degree of tumor penetration through the bowel wall, the presence or absence of nodal involvement, and the presence or absence of distant metastases. These three characteristics form the basis for all staging systems developed for this disease. Bowel obstruction and bowel perforation are indicators of poor prognosis. Elevated pretreatment serum levels of carcinoembryonic antigen (CEA) have a negative prognostic significance. The American Joint Committee on Cancer and a National Cancer Institute-sponsored panel recommended that at least 12 lymph nodes be examined in patients with colon and rectal cancer to confirm the absence of nodal involvement by tumor. This recommendation takes into consideration that the number of lymph nodes examined is a reflection of the aggressiveness of lymphovascular mesenteric dissection at the time of surgical resection and the pathologic identification of nodes in the specimen. Retrospective studies demonstrated that the number of lymph nodes examined in colon and rectal surgery may be associated with patient outcome.

Many other prognostic markers have been evaluated retrospectively for patients with colon cancer, though most have not been prospectively validated (including allelic loss of chromosome 18q or thymidylate synthase expression). Microsatellite instability, also associated with hereditary nonpolyposis colon cancer (HNPCC), has been associated with improved survival (independent of tumor stage) in a population-based series of 607 patients younger than 50 years of age with colorectal cancer. Treatment decisions generally depend on factors such as physician/patient preferences and the stage of the disease, rather than the age of the patient. Racial differences in overall survival after adjuvant therapy have been observed (although not in disease-free survival), suggesting that comorbid conditions play a role in survival outcome in different patient populations.

Source: National Cancer Institute, 2012
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.

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Your Matched Clinical Trials

Trial Matches: (D) - Disease, (G) - Gene, (M) - Mutation
Trial Status: Showing Results: 1-10 of 25 Per Page:
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Protocol # Title Location Status Match
NCT02279433 A First-in-human Study to Evaluate the Safety, Tolerability and Pharmacokinetics of DS-6051b A First-in-human Study to Evaluate the Safety, Tolerability and Pharmacokinetics of DS-6051b 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
NCT02327169 A Phase 1B Study of MLN2480 in Combination With MLN0128 or Alisertib, or Paclitaxel, or Cetuximab, or Irinotecan in Adult Patients With Advanced Nonhematologic Malignancies A Phase 1B Study of MLN2480 in Combination With MLN0128 or Alisertib, or Paclitaxel, or Cetuximab, or Irinotecan in Adult Patients With Advanced Nonhematologic Malignancies 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
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
NCT01714739 A Study of an Anti-KIR Antibody in Combination With an Anti-PD1 Antibody in Patients With Advanced Solid Tumors A Study of an Anti-KIR Antibody in Combination With an Anti-PD1 Antibody in Patients With Advanced Solid Tumors MGH Open D
NCT01633970 A Study of Atezolizumab Administered in Combination With Bevacizumab and/or With Chemotherapy in Participants With Locally Advanced or Metastatic Solid Tumors A Study of Atezolizumab Administered in Combination With Bevacizumab and/or With Chemotherapy in Participants With Locally Advanced or Metastatic Solid Tumors 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
NCT02082210 A Study of LY2875358 in Combination With Ramucirumab (LY3009806) in Participants With Advanced Cancer A Study of LY2875358 in Combination With Ramucirumab (LY3009806) in Participants With Advanced Cancer MGH Open D
NCT02060188 A Study of Nivolumab and Nivolumab Plus Ipilimumab in Recurrent and Metastatic Colon Cancer (CheckMate 142) A Study of Nivolumab and Nivolumab Plus Ipilimumab in Recurrent and Metastatic Colon Cancer (CheckMate 142) MGH Open D
Trial Status: Showing Results: 1-10 of 25 Per Page:
123Next »
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