Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2011-6-20
pubmed:abstractText
Trastuzumab (T) is effective in metastatic breast cancer (MBC) with HER2 overexpression and/or amplification, but resistance to T develops in a significant number of HER2-positive patients. Understanding the mechanisms of resistance is critical to the care of these patients. Formalin-fixed paraffin-embedded tumor tissue samples were collected from 256 patients with T-treated MBC. Clinical information was collected retrospectively from the patients' medical records. Central review of HER2 status by fluorescent in situ hybridization (FISH) and/or immunohistochemistry (IHC) revealed that of the 227 eligible patients only 139 (61%) were truly HER2-positive. PTEN, ER, PgR, and Ki67 were evaluated by IHC, while PTEN status was evaluated by FISH as well. PIK3CA mutations were identified with single nucleotide polymorphism (SNP) genotyping. Median time to progression (TTP) was 14.4 months for the HER2-positive and 10.3 for the HER2-negative patients (log-rank, P = 0.22). Survival from the initiation of T (survivalT) was 50.4 months for the HER2-positive and 35.3 for the HER2-negative subgroups (P = 0.006). Higher risk of progression was associated with HER2-positive status and the presence of PIK3CA mutations (P = 0.014). PTEN loss, as determined by IHC, was associated with lower survivalT in the whole population (P = 0.029) and in the HER2-positive population (P = 0.017). PIK3CA mutations and/or PTEN loss status were evaluated together as a single parameter, to estimate the impact of activation of the PI3K/AKT molecular pathway, and it was significantly associated with both decreased TTP (P = 0.003 in the total population, P = 0.004 in HER2-positive patients) and survival (survivalT, P = 0.011 in total, P = 0.006 in HER2-positive). In this trastuzumab-treated breast cancer population, PIK3CA activating mutations were associated with shorter TTP and PTEN loss with decreased survival. The activation of the PI3K/AKT pathway from either defect was associated with both TTP and survival, indicating the adverse effect of this pathway's status on trastuzumab efficacy.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Antibodies, Monoclonal, http://linkedlifedata.com/resource/pubmed/chemical/Antibodies, Monoclonal, Humanized, http://linkedlifedata.com/resource/pubmed/chemical/Antineoplastic Agents, http://linkedlifedata.com/resource/pubmed/chemical/DNA, Neoplasm, http://linkedlifedata.com/resource/pubmed/chemical/HER2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/PIK3CA protein, human, http://linkedlifedata.com/resource/pubmed/chemical/PTEN Phosphohydrolase, http://linkedlifedata.com/resource/pubmed/chemical/PTEN protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylinositol 3-Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-akt, http://linkedlifedata.com/resource/pubmed/chemical/Receptor, erbB-2, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Estrogen, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Progesterone, http://linkedlifedata.com/resource/pubmed/chemical/trastuzumab
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1573-7217
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
128
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
447-56
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:21594665-Adult, pubmed-meshheading:21594665-Aged, pubmed-meshheading:21594665-Aged, 80 and over, pubmed-meshheading:21594665-Antibodies, Monoclonal, pubmed-meshheading:21594665-Antibodies, Monoclonal, Humanized, pubmed-meshheading:21594665-Antineoplastic Agents, pubmed-meshheading:21594665-Bone Neoplasms, pubmed-meshheading:21594665-Breast Neoplasms, pubmed-meshheading:21594665-DNA, Neoplasm, pubmed-meshheading:21594665-Disease Progression, pubmed-meshheading:21594665-Female, pubmed-meshheading:21594665-Follow-Up Studies, pubmed-meshheading:21594665-Humans, pubmed-meshheading:21594665-Immunoenzyme Techniques, pubmed-meshheading:21594665-In Situ Hybridization, Fluorescence, pubmed-meshheading:21594665-Liver Neoplasms, pubmed-meshheading:21594665-Lung Neoplasms, pubmed-meshheading:21594665-Lymphatic Metastasis, pubmed-meshheading:21594665-Middle Aged, pubmed-meshheading:21594665-Mutation, pubmed-meshheading:21594665-PTEN Phosphohydrolase, pubmed-meshheading:21594665-Phosphatidylinositol 3-Kinases, pubmed-meshheading:21594665-Polymerase Chain Reaction, pubmed-meshheading:21594665-Polymorphism, Single Nucleotide, pubmed-meshheading:21594665-Proto-Oncogene Proteins c-akt, pubmed-meshheading:21594665-Receptor, erbB-2, pubmed-meshheading:21594665-Receptors, Estrogen, pubmed-meshheading:21594665-Receptors, Progesterone, pubmed-meshheading:21594665-Retrospective Studies, pubmed-meshheading:21594665-Survival Rate, pubmed-meshheading:21594665-Time Factors, pubmed-meshheading:21594665-Tissue Array Analysis, pubmed-meshheading:21594665-Treatment Outcome
pubmed:year
2011
pubmed:articleTitle
Evaluation of the association of PIK3CA mutations and PTEN loss with efficacy of trastuzumab therapy in metastatic breast cancer.
pubmed:affiliation
First Department of Medical Oncology, Hygeia Hospital, Er. Stavrou & Kifissias Av, 151 23 Maroussi, Athens, Greece. e.razis@hygeia.gr
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't