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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 PIK3CA  - General Description
CLICK IMAGE FOR MORE INFORMATION
PIK3CA is a gene that provides the code for making one piece of the phosphatidylinositol 3-kinase (PI3K) protein, which is an enzyme that is part of an important signaling pathway (PI3K/AKT) involved in controlling the growth, division, survival, nutrient utilization, movement and structure of cells. PIK3CA encodes the catalytic subunit of PI3K, which is the part of the protein that lets it function as an enzyme. PI3K function is tightly maintained in normal cells. The enzymatic activity is activated by specific signals from growth factor receptor tyrosine kinases (RTKs) or from activated RAS proteins. PI3K then generates molecules that attract another enzyme (particularly AKT) to the cell membrane, where it is activated. The activated AKT acts on other proteins that regulate various cell processes that promotes cell growth and survival.

Mutations in PIK3CA lead to enhanced activation of its signaling function, thereby driving the tumorigenic process. These activating mutations are commonly associated with breast and colon cancer, and more rarely with melanoma of the skin. Defects in this gene have also been associated with ovarian cancer, endometrial cancer, and liver cancer.

Tumor mutation profiling performed clinically at the MGH Cancer Center has identified PIK3CA mutations across a broad-spectrum of cancer types. The highest incidence of PIK3CA mutations have been found in endometrial cancer (25%), breast cancer (20%), colon cancer (25%) and cancers of the head and neck (10%). In the other major tumor types, PIK3CA mutations have been found in less than 10% of cases that have been tested.

Sources: Genetics Home Reference
The PIK3CA gene encodes the p110 alpha catalytic subunit of the phosphoinositol 3-kinase (PI3K) complex. PI3K receives upstream activation signals from growth factor receptor tyrosine kinases (e.g. EGFR family members), and in turn signals through AKT and mTOR in order to promote cell survival, cell growth and cellular proliferation. PIK3CA mutations lead to increased activation of PI3K/AKT/mTOR signaling. PI3K function is opposed by PTEN, a lipid phosphatase that is often inactivated by mutations or silenced by methylation in many cancers.

Tumor mutation profiling performed clinically at the MGH Cancer Center has identified PIK3CA mutations across a broad-spectrum of cancer types. The highest incidence of PIK3CA mutations have been found in endometrial cancer (25%), breast cancer (20%), colon cancer (25%) and cancers of the head and neck (10%). In the other major tumor types, PIK3CA mutations have been found in less than 10% of cases that have been tested.

Sources: Genetics Home Reference
Expand Collapse H1047Y (c.3139C>T)  in PIK3CA
The PIK3CA H1047Y mutation arises from a single nucleotide change (c.3139C>T) and results in an amino acid substitution of the histidine (H) at position 1047 by a tyrosine (Y).
The PIK3CA H1047Y mutation arises from a single nucleotide change (c.3139C>T) and results in an amino acid substitution of the histidine (H) at position 1047 by a tyrosine (Y).

The diagnostic relevance of PIK3CA mutations in colorectal adenocarcinoma has largely been limited to a single, large population-based study, which determined that PIK3CA mutations were more frequent in well-differentiated and mucinous colorectal tumors and tended to co-exist with KRAS mutations.

Results from the multi-institutional Dutch TME trial identified the presence of a PIK3CA mutation is associated with increased local recurrence in rectal cancer patients. Furthermore, a large population-based study has reported that the presence of an activating PIK3CA mutation is independently associated with shorter survival in patients with stage I to III resectable colorectal cancer, but only in the absence of a concurrent KRAS mutation. Interestingly, a recent retrospective study showed that regular aspirin use after diagnosis of early-stage colorectal cancer was associated with longer survival, but only among patients with PIK3CA-mutated tumors.

The therapeutic implications of PIK3CA mutations in colorectal cancer are the focus of ongoing investigations. Preliminary studies have implicated PIK3CA mutations as a mechanism of resistance to the anti-EGFR agent cetuximab or panitumumab in colorectal cancer. However, clinical follow-up is required to validate these findings. Preclinical studies have also demonstrated that PIK3CA mutations confer greater sensitivity to PI3K/AKT/mTOR inhibitors and early phase clinical trials are being conducted to evaluate their efficacy in the treatment of metastatic colorectal cancer. As PIK3CA mutations frequently coexist with KRAS mutations in colorectal cancer, trials with combination of PI3K pathway inhibitors and MEK inhibitors are underway.

The diagnostic relevance of PIK3CA mutations in colorectal adenocarcinoma has largely been limited to a single, large population-based study, which determined that PIK3CA mutations were more frequent in well-differentiated and mucinous colorectal tumors and tended to co-exist with KRAS mutations.

Results from the multi-institutional Dutch TME trial identified the presence of a PIK3CA mutation is associated with increased local recurrence in rectal cancer patients. Furthermore, a large population-based study has reported that the presence of an activating PIK3CA mutation is independently associated with shorter survival in patients with stage I to III resectable colorectal cancer, but only in the absence of a concurrent KRAS mutation. Interestingly, a recent retrospective study showed that regular aspirin use after diagnosis of early-stage colorectal cancer was associated with longer survival, but only among patients with PIK3CA-mutated tumors.

The therapeutic implications of PIK3CA mutations in colorectal cancer are the focus of ongoing investigations. Preliminary studies have implicated PIK3CA mutations as a mechanism of resistance to the anti-EGFR agent cetuximab or panitumumab in colorectal cancer. However, clinical follow-up is required to validate these findings. Preclinical studies have also demonstrated that PIK3CA mutations confer greater sensitivity to PI3K/AKT/mTOR inhibitors and early phase clinical trials are being conducted to evaluate their efficacy in the treatment of metastatic colorectal cancer. As PIK3CA mutations frequently coexist with KRAS mutations in colorectal cancer, trials with combination of PI3K pathway inhibitors and MEK inhibitors are underway.

PubMed ID's
20619739, 19237633, 18516290, 19223544, 15950905, 19401449, 19903786
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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
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
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
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
NCT01351103 A Study of LGK974 in Patients With Malignancies Dependent on Wnt Ligands A Study of LGK974 in Patients With Malignancies Dependent on Wnt Ligands MGH Open D
Trial Status: Showing Results: 1-10 of 30 Per Page:
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