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Expand Collapse Colorectal Cancer  - General Description Colorectal Cancer (CRC) is cancer that initiates in the colon or rectum-the lower part of the digestive system in the body. During digestion, food moves through the stomach and small intestine into the colon. The colon absorbs water and nutrients from food, and stores waste matter (stool) that moves from the colon through the rectum before leaving the body.

Most CRC's and rectal cancers are adenocarcinomas, meaning that they originate in cells that make and release mucus and other fluids. CRC often begins as a growth called a polyp, which may form on the inner wall of the colon or rectum. Over time, some polyps become cancerous. This highlights the importance of colonoscopy screening to find and remove polyps before they become cancerous.

CRC is the fourth most common type of cancer diagnosed in the U.S. Deaths from CRC have decreased with the use of colonoscopies and fecal occult blood tests, which check for blood in the stool. Disparities in survival have been observed between African American and other populations. This may be due to factors such as access to colonoscopy screening, or to other factors not yet identified.

Because of its prevalence, scientists have studied CRC extensively, even creating models of how cancer develops using CRC as an example. There are also families with a very high incidence of CRC occurrence. When these families were studied, certain conditions that create instability in the whole genome were identified that predispose people to CRC. These include what is called the chromosomal instability pathway (CIN) as well as microsatellite instability pathway (MSI). Both of these are recognized pathways in the development of CRC. These types of genetic instability lead to activation of proto-oncogenes such as KRAS, and the inactivation of tumor suppressors mentioned below.

Other genetic alterations in how the DNA in cells is organized have been found to contribute to CRC in families and individuals. These are called epigenetic changes. Normal DNA has methyl groups added in specific regions that regulate gene expression. When the genes that suppress growth-called tumor suppressors-are methylated in abnormal patterns, this prevents the production of tumor suppressor proteins that are important in controlling or stopping cell growth. When these are missing, unregulated growth occurs, contributing to the development of cancer. Some tumor suppressor proteins that are frequently inactivated in CRC are APC, TP53, and loss of one arm of chromosome 18 that contains a tumor suppressor.

The study of families with a high prevalence of CRC have lead scientists to discover genetic changes that contribute to the development of CRC in sporadic cases occurring in patients. Mutations in the genes encoding the following proteins have now been associated with subsets of CRC; AKT, APC, beta-catenin, BRAF, EGFR, ERBB2, ERBB3, IDH2, KRAS, NRAS, PIk3CA, PTEN, TP53,TRK 1, 2 and 3, and others still being identified.

Finally, distinct familial syndromes of CRC such as Lynch syndrome have been studied, and in these patients, the normal proof-reading of DNA during cell replication is found to be deficient. While DNA polymerase enzyme is replicating DNA before cells divide (with both daughter cells having a full complement of DNA), it occasionally makes errors. In a process of proof-reading behind this enzyme, several proteins form a complex to find and repair these mistakes. The process of proof-reading and restoring the DNA to the correct sequence is called mismatch repair (MMR). In Lynch syndrome, one or more of the proteins involved in MMR is mutated, and the mistakes in the DNA do not get corrected. The accumulation of these mistakes or mutations leads to cancer. Mutations in MMR proteins are not only found in familial cases of CRC, but also in patients with sporadic CRC. DNA repair machinery in the cell is important in keeping the genome stable and accurate. Defects in MMR also contribute to microsatellite instability (MIS), described above.

Testing for the mutations and genomic conditions that contribute to the development or progression of CRC are available at MGH in the sophisticated CLIA certified genomic testing lab, and in other large Centers and some private testing companies used by physicians. Validated treatments as well as clinical trials investigating improved targeted and immunologic therapies are available to patients at MGH.

NIH/NCI Cancer Website www.cancer.gov 2017
Genetic Alterations in CRC; Gastrointestinal Cancer Research; Amaghany T, et al.
Colorectal Cancer (CRC) is cancer that initiates in the colon or rectum-the lower part of the digestive system in the body. During digestion, food moves through the stomach and small intestine into the colon. The colon absorbs water and nutrients from food, and stores waste matter (stool) that moves from the colon through the rectum before leaving the body.

Most CRC's and rectal cancers are adenocarcinomas, meaning that they originate in cells that make and release mucus and other fluids. CRC often begins as a growth called a polyp, which may form on the inner wall of the colon or rectum. Over time, some polyps become cancerous. This highlights the importance of colonoscopy screening to find and remove polyps before they become cancerous.

CRC is the fourth most common type of cancer diagnosed in the U.S. Deaths from CRC have decreased with the use of colonoscopies and fecal occult blood tests, which check for blood in the stool. Disparities in survival have been observed between African American and other populations. This may be due to factors such as access to colonoscopy screening, or to other factors not yet identified.

Because of its prevalence, scientists have studied CRC extensively, even creating models of how cancer develops using CRC as an example. There are also families with a very high incidence of CRC occurrence. When these families were studied, certain conditions that create instability in the whole genome were identified that predispose people to CRC. These include what is called the chromosomal instability pathway (CIN) as well as microsatellite instability pathway (MSI). Both of these are recognized pathways in the development of CRC. These types of genetic instability lead to activation of proto-oncogenes such as KRAS, and the inactivation of tumor suppressors mentioned below.

Other genetic alterations in how the DNA in cells is organized have been found to contribute to CRC in families and individuals. These are called epigenetic changes. Normal DNA has methyl groups added in specific regions that regulate gene expression. When the genes that suppress growth-called tumor suppressors-are methylated in abnormal patterns, this prevents the production of tumor suppressor proteins that are important in controlling or stopping cell growth. When these are missing, unregulated growth occurs, contributing to the development of cancer. Some tumor suppressor proteins that are frequently inactivated in CRC are APC, TP53, and loss of one arm of chromosome 18 that contains a tumor suppressor.

The study of families with a high prevalence of CRC have lead scientists to discover genetic changes that contribute to the development of CRC in sporadic cases occurring in patients. Mutations in the genes encoding the following proteins have now been associated with subsets of CRC; AKT, APC, beta-catenin, BRAF, EGFR, ERBB2, ERBB3, IDH2, KRAS, NRAS, PIk3CA, PTEN, TP53,TRK 1, 2 and 3, and others still being identified.

Finally, distinct familial syndromes of CRC such as Lynch syndrome have been studied, and in these patients, the normal proof-reading of DNA during cell replication is found to be deficient. While DNA polymerase enzyme is replicating DNA before cells divide (with both daughter cells having a full complement of DNA), it occasionally makes errors. In a process of proof-reading behind this enzyme, several proteins form a complex to find and repair these mistakes. The process of proof-reading and restoring the DNA to the correct sequence is called mismatch repair (MMR). In Lynch syndrome, one or more of the proteins involved in MMR is mutated, and the mistakes in the DNA do not get corrected. The accumulation of these mistakes or mutations leads to cancer. Mutations in MMR proteins are not only found in familial cases of CRC, but also in patients with sporadic CRC. DNA repair machinery in the cell is important in keeping the genome stable and accurate. Defects in MMR also contribute to microsatellite instability (MIS), described above.

Testing for the mutations and genomic conditions that contribute to the development or progression of CRC are available at MGH in the sophisticated CLIA certified genomic testing lab, and in other large Centers and some private testing companies used by physicians. Validated treatments as well as clinical trials investigating improved targeted and immunologic therapies are available to patients at MGH.

NIH/NCI Cancer Website www.cancer.gov 2017
Genetic Alterations in CRC; Gastrointestinal Cancer Research; Amaghany T, et al.
Colorectal Cancer (CRC) is cancer that initiates in the colon or rectum-the lower part of the digestive system in the body. During digestion, food moves through the stomach and small intestine into the colon. The colon absorbs water and nutrients from food, and stores waste matter (stool) that moves from the colon through the rectum before leaving the body.

Most CRC's and rectal cancers are adenocarcinomas, meaning that they originate in cells that make and release mucus and other fluids. CRC often begins as a growth called a polyp, which may form on the inner wall of the colon or rectum. Over time, some polyps become cancerous. This highlights the importance of colonoscopy screening to find and remove polyps before they become cancerous.

CRC is the fourth most common type of cancer diagnosed in the U.S. Deaths from CRC have decreased with the use of colonoscopies and fecal occult blood tests, which check for blood in the stool. Disparities in survival have been observed between African American and other populations. This may be due to factors such as access to colonoscopy screening, or to other factors not yet identified.

Because of its prevalence, scientists have studied CRC extensively, even creating models of how cancer develops using CRC as an example. There are also families with a very high incidence of CRC occurrence. When these families were studied, certain conditions that create instability in the whole genome were identified that predispose people to CRC. These include what is called the chromosomal instability pathway (CIN) as well as microsatellite instability pathway (MSI). Both of these are recognized pathways in the development of CRC. These types of genetic instability lead to activation of proto-oncogenes such as KRAS, and the inactivation of tumor suppressors mentioned below.

Other genetic alterations in how the DNA in cells is organized have been found to contribute to CRC in families and individuals. These are called epigenetic changes. Normal DNA has methyl groups added in specific regions that regulate gene expression. When the genes that suppress growth-called tumor suppressors-are methylated in abnormal patterns, this prevents the production of tumor suppressor proteins that are important in controlling or stopping cell growth. When these are missing, unregulated growth occurs, contributing to the development of cancer. Some tumor suppressor proteins that are frequently inactivated in CRC are APC, TP53, and loss of one arm of chromosome 18 that contains a tumor suppressor.

The study of families with a high prevalence of CRC have lead scientists to discover genetic changes that contribute to the development of CRC in sporadic cases occurring in patients. Mutations in the genes encoding the following proteins have now been associated with subsets of CRC; AKT, APC, beta-catenin, BRAF, EGFR, ERBB2, ERBB3, IDH2, KRAS, NRAS, PIk3CA, PTEN, TP53,TRK 1, 2 and 3, and others still being identified.

Finally, distinct familial syndromes of CRC such as Lynch syndrome have been studied, and in these patients, the normal proof-reading of DNA during cell replication is found to be deficient. While DNA polymerase enzyme is replicating DNA before cells divide (with both daughter cells having a full complement of DNA), it occasionally makes errors. In a process of proof-reading behind this enzyme, several proteins form a complex to find and repair these mistakes. The process of proof-reading and restoring the DNA to the correct sequence is called mismatch repair (MMR). In Lynch syndrome, one or more of the proteins involved in MMR is mutated, and the mistakes in the DNA do not get corrected. The accumulation of these mistakes or mutations leads to cancer. Mutations in MMR proteins are not only found in familial cases of CRC, but also in patients with sporadic CRC. DNA repair machinery in the cell is important in keeping the genome stable and accurate. Defects in MMR also contribute to microsatellite instability (MIS), described above.

Testing for the mutations and genomic conditions that contribute to the development or progression of CRC are available at MGH in the sophisticated CLIA certified genomic testing lab, and in other large Centers and some private testing companies used by physicians. Validated treatments as well as clinical trials investigating improved targeted and immunologic therapies are available to patients at MGH.

NIH/NCI Cancer Website www.cancer.gov 2017
Genetic Alterations in CRC; Gastrointestinal Cancer Research; Amaghany T, et al.
Colorectal Cancer (CRC) is cancer that initiates in the colon or rectum-the lower part of the digestive system in the body. During digestion, food moves through the stomach and small intestine into the colon. The colon absorbs water and nutrients from food, and stores waste matter (stool) that moves from the colon through the rectum before leaving the body.

Most CRC's and rectal cancers are adenocarcinomas, meaning that they originate in cells that make and release mucus and other fluids. CRC often begins as a growth called a polyp, which may form on the inner wall of the colon or rectum. Over time, some polyps become cancerous. This highlights the importance of colonoscopy screening to find and remove polyps before they become cancerous.

CRC is the fourth most common type of cancer diagnosed in the U.S. Deaths from CRC have decreased with the use of colonoscopies and fecal occult blood tests, which check for blood in the stool. Disparities in survival have been observed between African American and other populations. This may be due to factors such as access to colonoscopy screening, or to other factors not yet identified.

Because of its prevalence, scientists have studied CRC extensively, even creating models of how cancer develops using CRC as an example. There are also families with a very high incidence of CRC occurrence. When these families were studied, certain conditions that create instability in the whole genome were identified that predispose people to CRC. These include what is called the chromosomal instability pathway (CIN) as well as microsatellite instability pathway (MSI). Both of these are recognized pathways in the development of CRC. These types of genetic instability lead to activation of proto-oncogenes such as KRAS, and the inactivation of tumor suppressors mentioned below.

Other genetic alterations in how the DNA in cells is organized have been found to contribute to CRC in families and individuals. These are called epigenetic changes. Normal DNA has methyl groups added in specific regions that regulate gene expression. When the genes that suppress growth-called tumor suppressors-are methylated in abnormal patterns, this prevents the production of tumor suppressor proteins that are important in controlling or stopping cell growth. When these are missing, unregulated growth occurs, contributing to the development of cancer. Some tumor suppressor proteins that are frequently inactivated in CRC are APC, TP53, and loss of one arm of chromosome 18 that contains a tumor suppressor.

The study of families with a high prevalence of CRC have lead scientists to discover genetic changes that contribute to the development of CRC in sporadic cases occurring in patients. Mutations in the genes encoding the following proteins have now been associated with subsets of CRC; AKT, APC, beta-catenin, BRAF, EGFR, ERBB2, ERBB3, IDH2, KRAS, NRAS, PIk3CA, PTEN, TP53,TRK 1, 2 and 3, and others still being identified.

Finally, distinct familial syndromes of CRC such as Lynch syndrome have been studied, and in these patients, the normal proof-reading of DNA during cell replication is found to be deficient. While DNA polymerase enzyme is replicating DNA before cells divide (with both daughter cells having a full complement of DNA), it occasionally makes errors. In a process of proof-reading behind this enzyme, several proteins form a complex to find and repair these mistakes. The process of proof-reading and restoring the DNA to the correct sequence is called mismatch repair (MMR). In Lynch syndrome, one or more of the proteins involved in MMR is mutated, and the mistakes in the DNA do not get corrected. The accumulation of these mistakes or mutations leads to cancer. Mutations in MMR proteins are not only found in familial cases of CRC, but also in patients with sporadic CRC. DNA repair machinery in the cell is important in keeping the genome stable and accurate. Defects in MMR also contribute to microsatellite instability (MIS), described above.

Testing for the mutations and genomic conditions that contribute to the development or progression of CRC are available at MGH in the sophisticated CLIA certified genomic testing lab, and in other large Centers and some private testing companies used by physicians. Validated treatments as well as clinical trials investigating improved targeted and immunologic therapies are available to patients at MGH.

NIH/NCI Cancer Website www.cancer.gov 2017
Genetic Alterations in CRC; Gastrointestinal Cancer Research; Amaghany T, et al.
PubMed ID's
2188735,
Expand Collapse EGFR  - General Description
CLICK IMAGE FOR MORE INFORMATION
The EGFR gene encodes for a cell-surface protein known as the epidermal growth factor receptor, which is found in many normal epithelial tissues such as the skin and hair follicles. When members of the epidermal growth factor family attach to EGFR, they activate several different cell signaling pathways that control various cell functions, including cell growth.

Mutations in EGFR can lead to unregulated activation of the protein. These types of activating mutations are often found in NSCLC (non-small cell lung cancer), glioblastoma and head and neck squamous cell carcinoma. Sometimes, excess EGFR protein is produced due to the presence of too many copies of the EGFR gene, leading to excessive cell division and growth in the presence of epidermal growth factor. Among the human cancers in which EGFR overabundance is present are cancers of the head and neck (squamous cell), colon, rectum, lung (NSCLC), central nervous system (glioblastoma), pancreas and breast (HER2-positive metastatic). Blocking EGFR in tumors may keep cancer cells from growing. The FDA has approved several therapies that target EGFR in one or more cancers.

Tumor mutation profiling performed clinically at the MGH Cancer Center has indicated that EGFR mutations occur primarily in lung cancer (~15%), but also in a minor subset of gastric (2%), brain (1%) and pancreatic (1%) cancers.

Source: Genetics Home Reference
The epidermal growth factor receptor (EGFR) gene encodes for a cell-surface protein that belongs to the ERBB family of receptor tyrosine kinases. Four members of the ERBB family have been identified: EGFR (ERBB1, HER1), ERBB2 (HER2), ERBB3 (HER3) and ERBB4 (HER4). Binding of a ligand induces ERBB receptor homo-/hetero-dimerization and triggers a signaling cascade that drives many cellular responses. These include the activation of PI3K-AKT/mTOR and MAP kinase/ERK pathways, which promote cell survival and proliferation. EGFR mutations have been most frequently associated with non-small cell lung cancer, but have also been described in other malignancies including gliomas, head and neck, prostate and ovarian tumors.

Tumor mutation profiling performed clinically at the MGH Cancer Center has indicated that EGFR mutations occur primarily in lung cancer (~15%), but also in a minor subset of gastric (2%), brain (1%) and pancreatic (1%) cancers.

Source: Genetics Home Reference
PubMed ID's
15864276, 15118073, 15118125, 15329413, 18772890, 15837736, 16720329, 21057220
Expand Collapse G719D (c.2156G>A)  in EGFR
The EGFR G719D mutation arises from the nucleotide change c.2156G>A in exon 18, resulting in an amino acid substitution of the glycine (G) at position 719 by an aspartic acid (D).
The EGFR G719D mutation arises from the nucleotide change c.2156G>A in exon 18, resulting in an amino acid substitution of the glycine (G) at position 719 by an aspartic acid (D).

The frequency of EGFR mutations in colorectal cancer is extremely low and the prognostic significance of these mutations has yet to be determined.

The therapeutic implications of EGFR mutations in colorectal cancer have not been determined. Therefore, it is unknown whether any particular EGFR gene mutation may confer sensitivity or resistance to EGFR small molecule inhibitors (such as erlotinib and gefitinib), as has been clearly demonstrated in non-small cell lung cancer.

The frequency of EGFR mutations in colorectal cancer is extremely low and the prognostic significance of these mutations has yet to be determined.

The therapeutic implications of EGFR mutations in colorectal cancer have not been determined. Therefore, it is unknown whether any particular EGFR gene mutation may confer sensitivity or resistance to EGFR small molecule inhibitors (such as erlotinib and gefitinib), as has been clearly demonstrated in non-small cell lung cancer.

PubMed ID's
15118125, 15118073, 15863375, 16166444, 15746034, 20184776, 20184776, 15625347, 16012179
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Your Matched Clinical Trials

Trial Matches: (D) - Disease, (G) - Gene, (M) - Mutation
Trial Status: Showing Results: 1-10 of 30 Per Page:
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Protocol # Title Location Status Match
NCT01953926 An Open-label, Phase 2 Study of Neratinib in Patients With Solid Tumors With Somatic Human Epidermal Growth Factor Receptor (EGFR, HER2, HER3) Mutations or EGFR Gene Amplification An Open-label, Phase 2 Study of Neratinib in Patients With Solid Tumors With Somatic Human Epidermal Growth Factor Receptor (EGFR, HER2, HER3) Mutations or EGFR Gene Amplification MGH Open DGM
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 DG
NCT02335918 A Dose Escalation and Cohort Expansion Study of Anti-CD27 (Varlilumab) and Anti-PD-1 (Nivolumab) in Advanced Refractory Solid Tumors A Dose Escalation and Cohort Expansion Study of Anti-CD27 (Varlilumab) and Anti-PD-1 (Nivolumab) in Advanced Refractory Solid Tumors MGH Open D
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
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
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
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
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
NCT02228811 A Study of DCC-2701 in Participants With Advanced Solid Tumors A Study of DCC-2701 in Participants With Advanced Solid Tumors MGH Open D
Trial Status: Showing Results: 1-10 of 30 Per Page:
123Next »
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