Showing papers on "Breast cancer published in 2009"

Supervised Risk Predictor of Breast Cancer Based on Intrinsic Subtypes

Abstract: Purpose To improve on current standards for breast cancer prognosis and prediction of chemotherapy benefit by developing a risk model that incorporates the gene expression–based “intrinsic” subtypes luminal A, luminal B, HER2-enriched, and basal-like. Methods A 50-gene subtype predictor was developed using microarray and quantitative reverse transcriptase polymerase chain reaction data from 189 prototype samples. Test sets from 761 patients (no systemic therapy) were evaluated for prognosis, and 133 patients were evaluated for prediction of pathologic complete response (pCR) to a taxane and anthracycline regimen. Results The intrinsic subtypes as discrete entities showed prognostic significance (P = 2.26E-12) and remained significant in multivariable analyses that incorporated standard parameters (estrogen receptor status, histologic grade, tumor size, and node status). A prognostic model for node-negative breast cancer was built using intrinsic subtype and clinical information. The C-index estimate for t...

Ki67 Index, HER2 Status, and Prognosis of Patients With Luminal B Breast Cancer

Abstract: Background Gene expression profiling of breast cancer has identified two biologically distinct estrogen receptor (ER)positive subtypes of breast cancer: luminal A and luminal B. Luminal B tumors have higher proliferation and poorer prognosis than luminal A tumors. In this study, we developed a clinically practical immunohistochemistry assay to distinguish luminal B from luminal A tumors and investigated its ability to separate tumors according to breast cancer recurrence-free and disease-specific survival. Methods Tumors from a cohort of 357 patients with invasive breast carcinomas were subtyped by gene expression profile. Hormone receptor status, HER2 status, and the Ki67 index (percentage of Ki67-positive cancer nuclei) were determined immunohistochemically. Receiver operating characteristic curves were used to determine the Ki67 cut point to distinguish luminal B from luminal A tumors. The prognostic value of the immunohistochemical assignment for breast cancer recurrence-free and disease-specific survival was investigated with an independent tissue microarray series of 4046 breast cancers by use of Kaplan – Meier curves and multivariable Cox regression. Results Gene expression profiling classified 101 (28%) of the 357 tumors as luminal A and 69 (19%) as luminal B. The best Ki67 index cut point to distinguish luminal B from luminal A tumors was 13.25%. In an independent cohort of 4046 patients with breast cancer, 2847 had hormone receptor – positive tumors. When HER2 immunohistochemistry and the Ki67 index were used to subtype these 2847 tumors, we classified 1530 (59%, 95% confidence interval [CI] = 57% to 61%) as luminal A, 846 (33%, 95% CI = 31% to 34%) as luminal B, and 222 (9%, 95% CI = 7% to 10%) as luminal – HER2 positive. Luminal B and luminal – HER2-positive breast cancers were statistically significantly associated with poor breast cancer recurrence-free and disease-specific survival in all adjuvant systemic treatment categories. Of particular relevance are women who received tamoxifen as their sole adjuvant systemic therapy, among whom the 10-year breast cancer – specific survival was 79% (95% CI = 76% to 83%) for luminal A, 64% (95% CI = 59% to 70%) for luminal B, and 57% (95% CI = 47% to 69%) for luminal – HER2 subtypes. Conclusion Expression of ER, progesterone receptor, and HER2 proteins and the Ki67 index appear to distinguish

Genes that mediate breast cancer metastasis to the brain

Abstract: The molecular basis for breast cancer metastasis to the brain is largely unknown. Brain relapse typically occurs years after the removal of a breast tumour, suggesting that disseminated cancer cells must acquire specialized functions to take over this organ. Here we show that breast cancer metastasis to the brain involves mediators of extravasation through non-fenestrated capillaries, complemented by specific enhancers of blood-brain barrier crossing and brain colonization. We isolated cells that preferentially infiltrate the brain from patients with advanced disease. Gene expression analysis of these cells and of clinical samples, coupled with functional analysis, identified the cyclooxygenase COX2 (also known as PTGS2), the epidermal growth factor receptor (EGFR) ligand HBEGF, and the alpha2,6-sialyltransferase ST6GALNAC5 as mediators of cancer cell passage through the blood-brain barrier. EGFR ligands and COX2 were previously linked to breast cancer infiltration of the lungs, but not the bones or liver, suggesting a sharing of these mediators in cerebral and pulmonary metastases. In contrast, ST6GALNAC5 specifically mediates brain metastasis. Normally restricted to the brain, the expression of ST6GALNAC5 in breast cancer cells enhances their adhesion to brain endothelial cells and their passage through the blood-brain barrier. This co-option of a brain sialyltransferase highlights the role of cell-surface glycosylation in organ-specific metastatic interactions.

Screening for Breast Cancer: US Preventive Services Task Force Recommendation Statement

Abstract: Description: Update of the 2002 U. S. Preventive Services Task Force (USPSTF) recommendation statement on screening for breast cancer in the general population. Methods: The USPSTF examined the evidence on the efficacy of 5 screening modalities in reducing mortality from breast cancer: film mammography, clinical breast examination, breast self-examination, digital mammography, and magnetic resonance imaging in order to update the 2002 recommendation. To accomplish this update, the USPSTF commissioned 2 studies: 1) a targeted systematic evidence review of 6 selected questions relating to benefits and harms of screening, and 2) a decision analysis that used population modeling techniques to compare the expected health outcomes and resource requirements of starting and ending mammography screening at different ages and using annual versus biennial screening intervals. Recommendations: The USPSTF recommends against routine screening mammography in women aged 40 to 49 years. The decision to start regular, biennial screening mammography before the age of 50 years should be an individual one and take into account patient context, including the patient's values regarding specific benefits and harms. (Grade C recommendation) The USPSTF recommends biennial screening mammography for women between the ages of 50 and 74 years. (Grade B recommendation) The USPSTF concludes that the current evidence is insufficient to assess the additional benefits and harms of screening mammography in women 75 years or older. (I statement) The USPSTF concludes that the current evidence is insufficient to assess the additional benefits and harms of clinical breast examination beyond screening mammography in women 40 years or older. (I statement) The USPSTF recommends against clinicians teaching women how to perform breast self-examination. (Grade D recommendation) The USPSTF concludes that the current evidence is insufficient to assess additional benefits and harms of either digital mammography or magnetic resonance imaging instead of film mammography as screening modalities for breast cancer. (I statement)

Residual breast cancers after conventional therapy display mesenchymal as well as tumor-initiating features

Abstract: Some breast cancers have been shown to contain a small fraction of cells characterized by CD44+/CD24−/low cell-surface antigen profile that have high tumor-initiating potential. In addition, breast cancer cells propagated in vitro as mammospheres (MSs) have also been shown to be enriched for cells capable of self-renewal. In this study, we have defined a gene expression signature common to both CD44+/CD24−/low and MS-forming cells. To examine its clinical significance, we determined whether tumor cells surviving after conventional treatments were enriched for cells bearing this CD44+/CD24−/low-MS signature. The CD44+/CD24−/low-MS signature was found mainly in human breast tumors of the recently identified “claudin-low” molecular subtype, which is characterized by expression of many epithelial-mesenchymal-transition (EMT)-associated genes. Both CD44+/CD24−/low-MS and claudin-low signatures were more pronounced in tumor tissue remaining after either endocrine therapy (letrozole) or chemotherapy (docetaxel), consistent with the selective survival of tumor-initiating cells posttreatment. We confirmed an increased expression of mesenchymal markers, including vimentin (VIM) in cytokeratin-positive epithelial cells metalloproteinase 2 (MMP2), in two separate sets of postletrozole vs. pretreatment specimens. Taken together, these data provide supporting evidence that the residual breast tumor cell populations surviving after conventional treatment may be enriched for subpopulations of cells with both tumor-initiating and mesenchymal features. Targeting proteins involved in EMT may provide a therapeutic strategy for eliminating surviving cells to prevent recurrence and improve long-term survival in breast cancer patients.

Gene-expression signatures in breast cancer.

Abstract: Gene-expression profiling with the use of DNA microarrays allows measurement of thousands of messenger RNA (mRNA) transcripts in a single experiment. Results of such studies have confirmed that breast cancer is not a single disease with variable morphologic features and biomarkers but, rather, a group of molecularly distinct neoplastic disorders. Profiling results also support the hypothesis that estrogen-receptor (ER)–negative and ER-positive breast cancers originate from distinct cell types and point to biologic processes that govern metastatic progression. Moreover, such profiling has uncovered molecular signatures that could influence clinical care. In this review, we summarize the results of gene-expression studies that hold the most promise to accelerate the transition between empirical and molecular medicine.

Biological determinants of endocrine resistance in breast cancer

Abstract: The efficacy of endocrine therapies (such as tamoxifen) in breast cancer is limited by intrinsic and acquired therapeutic resistance. What do we know about the genetic lesions and molecular processes that determine endocrine resistance in the clinic, and how can we use this to improve therapy? Endocrine therapies targeting oestrogen action (anti-oestrogens, such as tamoxifen, and aromatase inhibitors) decrease mortality from breast cancer, but their efficacy is limited by intrinsic and acquired therapeutic resistance. Candidate molecular biomarkers and gene expression signatures of tamoxifen response emphasize the importance of deregulation of proliferation and survival signalling in endocrine resistance. However, definition of the specific genetic lesions and molecular processes that determine clinical endocrine resistance is incomplete. The development of large-scale computational and genetic approaches offers the promise of identifying the mediators of endocrine resistance that may be exploited as potential therapeutic targets and biomarkers of response in the clinic.

PD 0332991, a selective cyclin D kinase 4/6 inhibitor, preferentially inhibits proliferation of luminal estrogen receptor-positive human breast cancer cell lines in vitro

Abstract: Introduction Alterations in cell cycle regulators have been implicated in human malignancies including breast cancer. PD 0332991 is an orally active, highly selective inhibitor of the cyclin D kinases (CDK)4 and CDK6 with ability to block retinoblastoma (Rb) phosphorylation in the low nanomolar range. To identify predictors of response, we determined the in vitro sensitivity to PD 0332991 across a panel of molecularly characterized human breast cancer cell lines. Methods Forty-seven human breast cancer and immortalized cell lines representing the known molecular subgroups of breast cancer were treated with PD 0332991 to determine IC50 values. These data were analyzed against baseline gene expression data to identify genes associated with PD 0332991 response.

Increased circulating myeloid-derived suppressor cells correlate with clinical cancer stage, metastatic tumor burden, and doxorubicin–cyclophosphamide chemotherapy

Abstract: Abnormal accumulation of myeloid-derived suppressor cells (MDSC) is an important mechanism of tumor immune evasion Cyclophosphamide (CTX) has also been shown in non-tumor bearing animals to cause transient surges in MDSC Knowledge of MDSC is primarily based on preclinical work, and to date only few published studies have involved cancer patients The goal of this study was to test the hypothesis that circulating MDSC levels correlate with clinical cancer stage, CTX-based chemotherapy, and metastatic tumor burden Whole blood was collected from 106 newly diagnosed solid tumor patients (stages I–IV) Percentages of circulating MDSC (Lin−/Lo, HLA DR−, CD33+CD11b+) were determined prior to initiation of systemic therapy In 17 early stage breast cancer patients receiving doxorubicin–cyclophosphamide chemotherapy every 14 days (ddAC) blood was collected on day 1 of each cycle Circulating MDSC were significantly increased in cancer patients of all stages relative to healthy volunteers A significant correlation between circulating MDSC and clinical cancer stage was also observed Moreover, among stage IV patients, those with extensive metastatic tumor burden had the highest percent and absolute number of MDSC Significant increases in circulating MDSC were observed with ddAC when compared with pretreatment levels Circulating MDSC levels correlate with clinical cancer stage, ddAC, and metastatic tumor burden This information must be incorporated into the design of future trials exploring immune-based therapeutic strategies Pharmacologic modulation of MDSC should also be tested in future clinical trials

Screening for breast cancer: an update for the U.S. Preventive Services Task Force.

Abstract: To inform the USPSTF recommendations about breast cancer screening, Nelson and coworkers reviewed evidence on the effectiveness of mammography screening in decreasing breast cancer mortality among ...

The HER-2 Receptor and Breast Cancer: Ten Years of Targeted Anti–HER-2 Therapy and Personalized Medicine

Abstract: The human epidermal growth factor receptor (HER-2) oncogene encodes a transmembrane tyrosine kinase receptor that has evolved as a major classifier of invasive breast cancer and target of therapy for the disease. The validation of the general prognostic significance of HER-2 gene amplification and protein overexpression in the absence of anti-HER-2 targeted therapy is discussed in a study of 107 published studies involving 39,730 patients, which produced an overall HER-2-positive rate of 22.2% and a mean relative risk for overall survival (OS) of 2.74. The issue of HER-2 status in primary versus metastatic breast cancer is considered along with a section on the features of metastatic HER-2-positive disease. The major marketed slide-based HER-2 testing approaches, immunohistochemistry, fluorescence in situ hybridization, and chromogenic in situ hybridization, are presented and contrasted in detail against the background of the published American Society of Clinical Oncology-College of American Pathologists guidelines for HER-2 testing. Testing issues, such as the impact of chromosome 17 polysomy and local versus central HER-2 testing, are also discussed. Emerging novel HER-2 testing techniques, including mRNA-based testing by real-time polymerase chain reaction and DNA microarray methods, HER-2 receptor dimerization, phosphorylated HER-2 receptors, and HER-2 status in circulating tumor cells, are also considered. A series of biomarkers potentially associated with resistance to trastuzumab is discussed with emphasis on the phosphatase and tensin homologue deleted on chromosome ten/Akt and insulin-like growth factor receptor pathways. The efficacy results for the more recently approved small molecule HER-1/HER-2 kinase inhibitor lapatinib are also presented along with a more limited review of markers of resistance for this agent. Additional topics in this section include combinations of both anti-HER-2 targeted therapies together as well as with novel agents including bevacizumab, everolimus, and tenespimycin. A series of novel HER-2-targeting agents is also presented, including pertuzumab, ertumaxomab, HER-2 vaccines, and recently discovered tyrosine kinase inhibitors. Biomarkers predictive of HER-2 targeted therapy toxicity are included, and the review concludes with a consideration of HER-2 status in the prediction of response to non-HER-2 targeted treatments including hormonal therapy, anthracyclines, and taxanes.

Mutational evolution in a lobular breast tumour profiled at single nucleotide resolution

Abstract: Recent advances in next generation sequencing have made it possible to precisely characterize all somatic coding mutations that occur during the development and progression of individual cancers. Here we used these approaches to sequence the genomes (>43-fold coverage) and transcriptomes of an oestrogen-receptor-alpha-positive metastatic lobular breast cancer at depth. We found 32 somatic non-synonymous coding mutations present in the metastasis, and measured the frequency of these somatic mutations in DNA from the primary tumour of the same patient, which arose 9 years earlier. Five of the 32 mutations (in ABCB11, HAUS3, SLC24A4, SNX4 and PALB2) were prevalent in the DNA of the primary tumour removed at diagnosis 9 years earlier, six (in KIF1C, USP28, MYH8, MORC1, KIAA1468 and RNASEH2A) were present at lower frequencies (1-13%), 19 were not detected in the primary tumour, and two were undetermined. The combined analysis of genome and transcriptome data revealed two new RNA-editing events that recode the amino acid sequence of SRP9 and COG3. Taken together, our data show that single nucleotide mutational heterogeneity can be a property of low or intermediate grade primary breast cancers and that significant evolution can occur with disease progression.

Metformin selectively targets cancer stem cells, and acts together with chemotherapy to block tumor growth and prolong remission

Abstract: The cancer stem cell hypothesis suggests that, unlike most cancer cells within a tumor, cancer stem cells resist chemotherapeutic drugs and can regenerate the various cell types in the tumor, thereby causing relapse of the disease. Thus, drugs that selectively target cancer stem cells offer great promise for cancer treatment, particularly in combination with chemotherapy. Here, we show that low doses of metformin, a standard drug for diabetes, inhibits cellular transformation and selectively kills cancer stem cells in four genetically different types of breast cancer. The combination of metformin and a well-defined chemotherapeutic agent, doxorubicin, kills both cancer stem cells and non-stem cancer cells in culture. Furthermore, this combinatorial therapy reduces tumor mass and prevents relapse much more effectively than either drug alone in a xenograft mouse model. Mice seem to remain tumor-free for at least 2 months after combinatorial therapy with metformin and doxorubicin is ended. These results provide further evidence supporting the cancer stem cell hypothesis, and they provide a rationale and experimental basis for using the combination of metformin and chemotherapeutic drugs to improve treatment of patients with breast (and possibly other) cancers.

Endocrine Therapy plus Zoledronic Acid in Premenopausal Breast Cancer

Abstract: After a median follow-up of 47.8 months, 137 events had occurred, with disease-free survival rates of 92.8% in the tamoxifen group, 92.0% in the anastrozole group, 90.8% in the group that received endocrine therapy alone, and 94.0% in the group that received endocrine therapy with zoledronic acid. There was no significant dif ference in disease-free survival between the anastrozole and tamoxifen groups (haz ard ratio for disease progression in the anastrozole group, 1.10; 95% confidence in terval [CI], 0.78 to 1.53; P = 0.59). The addition of zoledronic acid to endocrine therapy, as compared with endocrine therapy without zoledronic acid, resulted in an absolute reduction of 3.2 percentage points and a relative reduction of 36% in the risk of dis ease progression (hazard ratio, 0.64; 95% CI, 0.46 to 0.91; P = 0.01); the addition of zoledronic acid did not significantly reduce the risk of death (hazard ratio, 0.60; 95% CI, 0.32 to 1.11; P = 0.11). Adverse events were consistent with known drug-safety profiles. Conclusions The addition of zoledronic acid to adjuvant endocrine therapy improves disease-free survival in premenopausal patients with estrogen-responsive early breast cancer. (ClinicalTrials.gov number, NCT00295646.)

Lapatinib Combined With Letrozole Versus Letrozole and Placebo As First-Line Therapy for Postmenopausal Hormone Receptor–Positive Metastatic Breast Cancer

Abstract: Purpose Cross-talk between human epidermal growth factor receptors and hormone receptor pathways may cause endocrine resistance in breast cancer. This trial evaluated the effect of adding lapatinib, a dual tyrosine kinase inhibitor blocking epidermal growth factor receptor and human epidermal growth factor receptor 2 (HER2), to the aromatase inhibitor letrozole as first-line treatment of hormone receptor (HR) –positive metastatic breast cancer (MBC). Patients and Methods Postmenopausal women with HR-positive MBC were randomly assigned to daily letrozole (2.5 mg orally) plus lapatinib (1,500 mg orally) or letrozole and placebo. The primary end point was progression-free survival (PFS) in the HER2-positive population. Results In HR-positive, HER2-positive patients (n 219), addition of lapatinib to letrozole significantly reduced the risk of disease progression versus letrozole-placebo (hazard ratio [HR] 0.71; 95% CI, 0.53 to 0.96; P .019); median PFS was 8.2 v 3.0 months, respectively. Clinical benefit (responsive or stable disease 6 months) was significantly greater for lapatinib-letrozole versus letrozole-placebo (48% v 29%, respectively; odds ratio [OR] 0.4; 95% CI, 0.2 to 0.8; P .003). Patients with centrally confirmed HR-positive, HER2-negative tumors (n 952) had no improvement in PFS. A preplanned Cox regression analysis identified prior antiestrogen therapy as a significant factor in the HER2-negative population; a nonsignificant trend toward prolonged PFS for lapatinib-letrozole was seen in patients who experienced relapse less than 6 months since prior tamoxifen discontinuation (HR 0.78; 95% CI, 0.57 to 1.07; P .117). Grade 3 or 4 adverse events were more common in the lapatinib-letrozole arm versus letrozole-placebo arm (diarrhea, 10% v 1%; rash, 1% v 0%, respectively), but they were manageable.

Sarcopenia as a determinant of chemotherapy toxicity and time to tumor progression in metastatic breast cancer patients receiving capecitabine treatment.

Abstract: Purpose: Body composition has emerged as an important prognostic factor in cancer patients. Severe depletion of skeletal muscle (sarcopenia) and, hence, of overall lean body mass may represent an occult condition in individuals with normal or even high body weight. Sarcopenia has been associated with poor performance status, 5-fluorouracil toxicity, and shortened survival in cancer patients. Here, we prospectively studied patients with metastatic breast cancer receiving capecitabine treatment in order to determine if sarcopenia was associated with a higher incidence of toxicity and a shorter time to tumor progression (TTP). Experimental Design: Fifty-five women with metastatic breast cancer resistant to anthracycline and/or taxane treatment were included. Skeletal muscle cross-sectional area at the third lumbar vertebra was measured by computerized tomography, and sarcopenia was defined using a previously published cutoff point. Toxicity was assessed after cycle 1 of treatment, and TTP was determined prospectively. Results: Approximately 25% of patients were classified as sarcopenic, and this feature was seen in normal weight, overweight, and obese individuals. Toxicity was present in 50% of sarcopenic patients, compared with only 20% of nonsarcopenic patients ( P = 0.03), and TTP was shorter in sarcopenic patients (101.4 days; confidence interval, 59.8-142.9) versus nonsarcopenic patients (173.3 days; confidence interval, 126.1-220.5; P = 0.05). Conclusion: Sarcopenia is a significant predictor of toxicity and TTP in metastatic breast cancer patients treated with capecitabine. Our results raise the potential use of body composition assessment to predict toxicity and individualize chemotherapy dosing.

Breast Cancer Subtypes Based on ER/PR and Her2 Expression: Comparison of Clinicopathologic Features and Survival

Abstract: Over the last few decades there have been outstanding advances in breast cancer management leading to earlier detection of disease and the development of more effective treatments resulting in significant declines in breast cancer deaths and improved outcomes for women living with the disease.1,2 Breast cancer is no longer seen as a single disease but rather a multifaceted disease comprised of distinct biological subtypes with diverse natural history, presenting a varied spectrum of clinical, pathologic and molecular features with different prognostic and therapeutic implications. Consensus regarding the definitive prognostic/predictive analysis has yet to be reached, but significant progress continues to be made in the ongoing search for a specific, rigorous and reproducible method of identifying successful treatment algorithms utilizing biological markers. Recent attention has been directed singularly at molecular classifications of breast cancer.3–11 While molecular and genetic testing is very elegant, prognostic and predictive, it is expensive and not yet widely available. Also, despite the prognostic information provided by the molecular test, current reports of assay results impart little specific guidance of response to targeted and proven therapy; for example, endocrine and trastuzumab therapy for tumors expressing estrogen receptor/progesterone receptor (ER/PR) or human epidermal growth factor receptor 2 (Her2) proteins, respectively. The immunohistochemistry (IHC) classification provides both therapeutic and prognostic information. In this study breast cancer is classified into four groups based on IHC profile ER/PR and Her2/neu expression, positive (+) and/or negative (−). The groups are: ER/PR+, Her2+ = ER+/PR+, Her2+; ER−/PR+, Her2+; ER+/PR−, Her2+ ER/PR+, Her2− = ER+/PR+, Her2−; ER−/PR+, Her2−; ER+/PR−, Her2− ER/PR−, Her2+ = ER−/PR−, Her2+ ER/PR−, Her2− = ER−/PR−, Her2− The IHC classification correlates well with intrinsic gene expression microarray categorization: ER/PR+, Her2+ with Luminal B; ER/PR+, Her2− with Luminal A; ER/PR−, Her2+ and ER/PR−, Her2− with triple negative/basal-like tumors.1 Apart from lending itself to subtype analyses of tumor when fresh tissue is not available, the IHC classification has prognostic and therapeutic implications, is inexpensive and readily available.

Metformin and Pathologic Complete Responses to Neoadjuvant Chemotherapy in Diabetic Patients With Breast Cancer

Abstract: Purpose Population studies have suggested that metformin use in diabetic patients decreases cancer incidence and mortality. Metformin inhibits the growth of cancer cells in vitro and tumors in vivo. However, there is little clinical data to support this. Our purpose was to determine whether metformin use was associated with a change in pathologic complete response (pCR) rates in diabetic patients with breast cancer receiving neoadjuvant chemotherapy. Patients and Methods We identified 2,529 patients who received neoadjuvant chemotherapy for early-stage breast cancer between 1990 and 2007. Patients were compared by groups: 68 diabetic patients taking metformin, 87 diabetic patients not taking metformin, and 2,374 nondiabetic patients. pCR rates were compared between the three groups using 2 tests of independence and compared pairwise using a binomial test of proportions. Factors predictive of pCR were assessed using a multivariate logistic regression model. Results The rate of pCR was 24% in the metformin group, 8.0% in the nonmetformin group, and 16% in the nondiabetic group (P .02). Pairwise comparisons between the metformin and nonmetformin groups (P .007) and the nonmetformin and nondiabetic groups (P .04) were significant. Comparison of the pCR rates between the metformin and nondiabetic groups trended toward but did not meet significance (P .10). Metformin use was independently predictive of pCR (odds ratio, 2.95; P .04) after adjustment for diabetes, body mass index, age, stage, grade, receptor status, and neoadjuvant taxane use. Conclusion Diabetic patients with breast cancer receiving metformin and neoadjuvant chemotherapy have a higher pCR rate than do diabetics not receiving metformin. Additional studies to evaluate the potential of metformin as an antitumor agent are warranted.

Characterization of a naturally occurring breast cancer subset enriched in epithelial-to-mesenchymal transition and stem cell characteristics.

Abstract: Metaplastic breast cancers (MBC) are aggressive, chemoresistant tumors characterized by lineage plasticity. To advance understanding of their pathogenesis and relatedness to other breast cancer subtypes, 28 MBCs were compared with common breast cancers using comparative genomic hybridization, transcriptional profiling, and reverse-phase protein arrays and by sequencing for common breast cancer mutations. MBCs showed unique DNA copy number aberrations compared with common breast cancers. PIK3CA mutations were detected in 9 of 19 MBCs (47.4%) versus 80 of 232 hormone receptor-positive cancers (34.5%; P = 0.32), 17 of 75 HER-2-positive samples (22.7%; P = 0.04), 20 of 240 basal-like cancers (8.3%; P < 0.0001), and 0 of 14 claudin-low tumors (P = 0.004). Of 7 phosphatidylinositol 3-kinase/AKT pathway phosphorylation sites, 6 were more highly phosphorylated in MBCs than in other breast tumor subtypes. The majority of MBCs displayed mRNA profiles different from those of the most common, including basal-like cancers. By transcriptional profiling, MBCs and the recently identified claudin-low breast cancer subset constitute related receptor-negative subgroups characterized by low expression of GATA3-regulated genes and of genes responsible for cell-cell adhesion with enrichment for markers linked to stem cell function and epithelial-to-mesenchymal transition (EMT). In contrast to other breast cancers, claudin-low tumors and most MBCs showed a significant similarity to a "tumorigenic" signature defined using CD44(+)/CD24(-) breast tumor-initiating stem cell-like cells. MBCs and claudin-low tumors are thus enriched in EMT and stem cell-like features, and may arise from an earlier, more chemoresistant breast epithelial precursor than basal-like or luminal cancers. PIK3CA mutations, EMT, and stem cell-like characteristics likely contribute to the poor outcomes of MBC and suggest novel therapeutic targets.

Molecular Profiling of Breast Cancer Cell Lines Defines Relevant Tumor Models and Provides a Resource for Cancer Gene Discovery

Abstract: Background Breast cancer cell lines have been used widely to investigate breast cancer pathobiology and new therapies. Breast cancer is a molecularly heterogeneous disease, and it is important to understand how well and which cell lines best model that diversity. In particular, microarray studies have identified molecular subtypes–luminal A, luminal B, ERBB2-associated, basal-like and normal-like–with characteristic gene-expression patterns and underlying DNA copy number alterations (CNAs). Here, we studied a collection of breast cancer cell lines to catalog molecular profiles and to assess their relation to breast cancer subtypes.

Prevalence of and factors associated with persistent pain following breast cancer surgery.

Abstract: Context Persistent pain and sensory disturbances following surgical treatment for breast cancer is a significant clinical problem. The pathogenic mechanisms are complex and may be related to patient characteristics, surgical technique, and adjuvant therapy. Objective To examine prevalence of and factors associated with persistent pain after surgical treatment for breast cancer. Design, Setting, and Patients A nationwide cross-sectional questionnaire study of 3754 women aged 18 to 70 years who received surgery and adjuvant therapy (if indicated) for primary breast cancer in Denmark between January 1, 2005, and December 31, 2006. A study questionnaire was sent to the women between January and April 2008. Main Outcome Measures Prevalence, location, and severity of persistent pain and sensory disturbances in 12 well-defined treatment groups assessed an average of 26 months after surgery, and adjusted odds ratio (OR) of reported pain and sensory disturbances with respect to age, surgical technique, chemotherapy, and radiotherapy. Results By June 2008, 3253 of 3754 eligible women (87%) returned the questionnaire. A total of 1543 patients (47%) reported pain, of whom 201 (13%) had severe pain, 595 (39%) had moderate pain, and 733 (48%) had light pain. Factors associated with chronic pain included young age (18-39 years: OR, 3.62; 95% confidence interval [CI], 2.25-5.82;P Conclusion Two to 3 years after breast cancer treatment, persistent pain and sensory disturbances remain clinically significant problems among Danish women who received surgery in 2005 and 2006.

Meta-analysis of Risk Reduction Estimates Associated With Risk-Reducing Salpingo-oophorectomy in BRCA1 or BRCA2 Mutation Carriers

Abstract: mutations to reduce their risks of breast and ovarian cancer. To guide women and their clinicians in optimizing cancer prevention strategies, we summarized the magnitude of the risk reductions in women with BRCA1/2 mutations who have undergone RRSO compared with those who have not. Methods All reports of RRSO and breast and/or ovarian or fallopian tube cancer in BRCA1/2 mutation carriers published between 1999 and 2007 were obtained from a PubMed search. Hazard ratio (HR) estimates were identified directly from the original articles. Pooled results were computed from nonoverlapping studies by fixed-effects meta-analysis. Results Ten studies investigated breast or gynecologic cancer outcomes in BRCA1/2 mutation carriers who had undergone RRSO. Breast cancer outcomes were investigated in three nonoverlapping studies of BRCA1/2 mutation carriers, four of BRCA1 mutation carriers, and three of BRCA2 mutation carriers. Gynecologic cancer outcomes were investigated in three nonoverlapping studies of BRCA1/2 mutation carriers and one of BRCA1 mutation carriers. RRSO was associated with a statistically significant reduction in risk of breast cancer in BRCA1/2 mutation carriers (HR = 0.49; 95% confidence interval [CI] = 0.37 to 0.65). Similar risk reductions were observed in BRCA1 mutation carriers (HR = 0.47; 95% CI = 0.35 to 0.64) and in BRCA2 mutation carriers (HR = 0.47; 95% CI = 0.26 to 0.84). RRSO was also associated with a statistically significant reduction in the risk of BRCA1/2 -associated ovarian or fallopian tube cancer (HR = 0.21; 95% CI = 0.12 to 0.39). Data were insufficient to obtain separate estimates for ovarian or fallopian tube cancer risk reduction with RRSO in BRCA1 or BRCA2 mutation carriers. Conclusion The summary estimates presented here indicate that RRSO is strongly associated with reductions in the risk of breast, ovarian, and fallopian tube cancers and should provide guidance to women in planning cancer risk reduction strategies.

Trastuzumab plus anastrozole versus anastrozole alone for the treatment of postmenopausal women with human epidermal growth factor receptor 2-positive, hormone receptor-positive metastatic breast cancer: results from the randomized phase III TAnDEM study.

Abstract: Purpose TAnDEM is the first randomized phase III study to combine a hormonal agent and trastuzumab without chemotherapy as treatment for human epidermal growth factor receptor 2 (HER2)/hormone receptor–copositive metastatic breast cancer (MBC). Patients and Methods Postmenopausal women with HER2/hormone receptor–copositive MBC were randomly assigned to anastrozole (1 mg/d orally) with or without trastuzumab (4 mg/kg intravenous infusion on day 1, then 2 mg/kg every week) until progression. The primary end point was progression-free survival (PFS) in the intent-to-treat population. Results Overall, 103 patients received trastuzumab plus anastrozole; 104 received anastrozole alone. Patients in the trastuzumab plus anastrozole arm experienced significant improvements in PFS compared with patients receiving anastrozole alone (hazard ratio = 0.63; 95% CI, 0.47 to 0.84; median PFS, 4.8 v 2.4 months; log-rank P = .0016). In patients with centrally confirmed hormone receptor positivity (n = 150), median PFS was 5...

Support vector machines combined with feature selection for breast cancer diagnosis

Abstract: Breast cancer is the second largest cause of cancer deaths among women. At the same time, it is also among the most curable cancer types if it can be diagnosed early. Research efforts have reported with increasing confirmation that the support vector machines (SVM) have greater accurate diagnosis ability. In this paper, breast cancer diagnosis based on a SVM-based method combined with feature selection has been proposed. Experiments have been conducted on different training-test partitions of the Wisconsin breast cancer dataset (WBCD), which is commonly used among researchers who use machine learning methods for breast cancer diagnosis. The performance of the method is evaluated using classification accuracy, sensitivity, specificity, positive and negative predictive values, receiver operating characteristic (ROC) curves and confusion matrix. The results show that the highest classification accuracy (99.51%) is obtained for the SVM model that contains five features, and this is very promising compared to the previously reported results.

Stem cell and epithelial-mesenchymal transition markers are frequently overexpressed in circulating tumor cells of metastatic breast cancer patients

Abstract: The persistence of circulating tumor cells (CTC) in breast cancer patients might be associated with stem cell like tumor cells which have been suggested to be the active source of metastatic spread in primary tumors. Furthermore, these cells also may undergo phenotypic changes, known as epithelial-mesenchymal transition (EMT), which allows them to travel to the site of metastasis formation without getting affected by conventional treatment. Here we evaluated 226 blood samples of 39 metastatic breast cancer patients during a follow-up of palliative chemo-, antibody – or hormonal therapy for the expression of the stem cell marker ALDH1 and markers for EMT and correlated these findings with the presence of CTC and response to therapy. 2 × 5 ml blood was analyzed for CTC with the AdnaTest BreastCancer (AdnaGen AG) for the detection of EpCAM, MUC-1 and HER2 transcripts. The recovered c-DNA was additionally multiplex tested for three EMT markers [Twist1, Akt2, PI3Kα] and separately for the tumor stem-cell markers ALDH1. The identification of EMT markers was considered positive if at least one marker was detected in the sample. 97% of 30 healthy donor samples investigated were negative for EMT and 95% for ALDH1 transcripts. CTC were detected in 69/226 (31%) cancer samples. In the CTC (+) group, 62% were positive for at least one of the EMT markers and 69% for ALDH1, respectively. In the CTC (-) group the percentages were 7% and 14%, respectively. In non-responders, EMT and ALDH1 expression was found in 62% and 44% of patients, in responders the rates were 10% and 5%, respectively. Our data indicate that a major proportion of CTC of metastatic breast cancer patients shows EMT and tumor stem cell characteristics. Further studies are needed to prove whether these markers might serve as an indicator for therapy resistant tumor cell populations and, therefore, an inferior prognosis.

Impact of socioeconomic status on cancer incidence and stage at diagnosis: selected findings from the surveillance, epidemiology, and end results: National Longitudinal Mortality Study

Abstract: Background Population-based cancer registry data from the Surveillance, Epidemiology, and End Results (SEER) Program at the National Cancer Institute (NCI) are mainly based on medical records and administrative information. Individual-level socioeconomic data are not routinely reported by cancer registries in the United States because they are not available in patient hospital records. The U.S. representative National Longitudinal Mortality Study (NLMS) data provide self-reported, detailed demographic and socioeconomic data from the Social and Economic Supplement to the Census Bureau’s Current Population Survey (CPS). In 1999, the NCI initiated the SEER-NLMS study, linking the population-based SEER cancer registry data to NLMS data. The SEER-NLMS data provide a new unique research resource that is valuable for health disparity research on cancer burden. We describe the design, methods, and limitations of this data set. We also present findings on cancer-related health disparities according to individual-level socioeconomic status (SES) and demographic characteristics for all cancers combined and for cancers of the lung, breast, prostate, cervix, and melanoma.

Albumin-bound formulation of paclitaxel (Abraxane ABI-007) in the treatment of breast cancer.

Abstract: Breast cancer is the most common type of malignancy diagnosed in women. In the metastatic setting this disease is still uncurable. Taxanes represent an important class of antitumor agents which have proven to be fundamental in the treatment of advanced and early-stage breast cancer, but the clinical advances of taxanes have been limited by their highly hydrophobic molecular status. To overcome this poor water solubility, lipid-based solvents have been used as a vehicle, and new systemic formulations have been developed, mostly for paclitaxel, which are Cremophor-free and increase the circulation time of the drug. ABI-007 is a novel, albumin-bound, 130-nm particle formulation of paclitaxel, free from any kind of solvent. It has been demonstrated to be superior to an equitoxic dose of standard paclitaxel with a significantly lower incidence of toxicities in a large, international, randomized phase III trial. The availability of new drugs, such as Abraxane, in association with other traditional and non-traditional drugs (new antineoplastic agents and targeted molecules), will give the oncologist many different effective treatment options for patients in this setting.