Breast Cancer, PIK3CA, Q546L (c.1637A>T)

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

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

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

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

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

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

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

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

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

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

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

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

Source: National Cancer Institute, 2017
Expand Collapse PIK3CA  - General Description
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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. The MGH Cancer Center is a world leader in the treatment of PIK3CA mutated tumors, as well as in the number of clinical trials available for treatment with new therapies against tumors with PIK3CA mutations.

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 Q546L (c.1637A>T)  in PIK3CA
The PIK3CA Q546L mutation arises from a single nucleotide change (c.1637A>T) and results in an amino acid substitution of the glutamine (Q) at position 546 by a leucine (L).
The PIK3CA Q546L mutation arises from a single nucleotide change (c.1637A>T) and results in an amino acid substitution of the glutamine (Q) at position 546 by a leucine (L).

PIK3CA mutations are most commonly found in hormone receptor positive breast cancer, followed by HER2 positive breast cancer, and si least often found in triple-negative cancer. PIK2CA mutations are generally associated with a more favorable prognosis in early-stage disease, such as hormone receptor positivity and lymph node negativity and better overall survival.

Mutant PIK3CA proteins have increased activity that has been associated with resistance to endocrine therapy and decreased response rates to trastuzumab (a HER2-targeted antibody) or lapatinib (an EGFR and HER2 inhibitor).

Preclinical studies have shown that PIK3CA-mutant and HER2-amplified breast cancers are more sensitive to PI3K pathway inhibitors, when given either as a single-agent or in combination with other targeted therapies. Multiple clinical trials are currently underway to validate this hypothesis.

PIK3CA mutations are most commonly found in hormone receptor positive breast cancer, followed by HER2 positive breast cancer, and si least often found in triple-negative cancer. PIK2CA mutations are generally associated with a more favorable prognosis in early-stage disease, such as hormone receptor positivity and lymph node negativity and better overall survival.

Mutant PIK3CA proteins have increased activity that has been associated with resistance to endocrine therapy and decreased response rates to trastuzumab (a HER2-targeted antibody) or lapatinib (an EGFR and HER2 inhibitor).

Preclinical studies have shown that PIK3CA-mutant and HER2-amplified breast cancers are more sensitive to PI3K pathway inhibitors, when given either as a single-agent or in combination with other targeted therapies. Multiple clinical trials are currently underway to validate this hypothesis.

PubMed ID's
18676830, 21135276, 20085938, 21135276, 23400000
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Your Matched Clinical Trials

Trial Matches: (D) - Disease, (G) - Gene, (M) - Mutation
Trial Status: Showing all 9 results Per Page:
Protocol # Title Location Status Match
NCT02099058 A Study Evaluating the Safety, Pharmacokinetics (PK), and Preliminary Efficacy of ABBV-399 in Subjects With Advanced Solid Tumors A Study Evaluating the Safety, Pharmacokinetics (PK), and Preliminary Efficacy of ABBV-399 in Subjects With Advanced Solid Tumors MGH Open D
NCT01325441 A Study of BBI608 Administered With Paclitaxel in Adult Patients With Advanced Malignancies A Study of BBI608 Administered With Paclitaxel in Adult Patients With Advanced Malignancies MGH Open D
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
NCT02939274 An Open Label, Phase II Trial of Continuous Low-Irradiance Photodynamic Therapy (CLIPT) Using Verteporfin (Visudyne®) for the Treatment of Cutaneous Metastases of Breast Cancer An Open Label, Phase II Trial of Continuous Low-Irradiance Photodynamic Therapy (CLIPT) Using Verteporfin (Visudyne®) for the Treatment of Cutaneous Metastases of Breast Cancer MGH Open D
NCT02574455 ASCENT-Study of Sacituzumab Govitecan in Refractory/Relapsed Triple-Negative Breast Cancer ASCENT-Study of Sacituzumab Govitecan in Refractory/Relapsed Triple-Negative Breast Cancer MGH Open D
NCT02568267 Basket Study of Entrectinib (RXDX-101) for the Treatment of Patients With Solid Tumors Harboring NTRK 1/2/3 (Trk A/B/C), ROS1, or ALK Gene Rearrangements (Fusions) Basket Study of Entrectinib (RXDX-101) for the Treatment of Patients With Solid Tumors Harboring NTRK 1/2/3 (Trk A/B/C), ROS1, or ALK Gene Rearrangements (Fusions) MGH Open D
NCT01494662 HKI-272 for HER2-Positive Breast Cancer and Brain Metastases HKI-272 for HER2-Positive Breast Cancer and Brain Metastases MGH Open D
NCT01953926 Neratinib HER Mutation Basket Study (SUMMIT) Neratinib HER Mutation Basket Study (SUMMIT) MGH Open D
NCT01872975 Standard or Comprehensive Radiation Therapy in Treating Patients With Early-Stage Breast Cancer Previously Treated With Chemotherapy and Surgery Standard or Comprehensive Radiation Therapy in Treating Patients With Early-Stage Breast Cancer Previously Treated With Chemotherapy and Surgery MGH Open D
MGH has many open clinical trials for other cancers not shown on the Targeted Cancer Care website. They can be found on the MassGeneral.org clinical trials search page.

Additional clinical trials may be applicable to your search criteria, but they may not be available at MGH. These clinical trials can typically be found by searching the clinicaltrials.gov website.
Trial Status: Showing all 9 results Per Page:
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