bluuebunny/crossref_metadata_2025_split huggingface dataset:
Truncated p95erbB2 Isoforms Are Capable of Transforming Human Mammary Epithelial Cells.
Authors: Ward T. , Iorns E. , Gallas M. , Lippman M. , Landgraf R. , Pegram M. 
Published: December 2010

Abstract
Background:Objective clinical response to trastuzumab monotherapy in erbB2-amplified first line metastatic breast cancer is 34% (Vogel, et al., JCO 20: 719-26, 2002). Amongst patients who respond, most develop resistance (defined by disease progression on trastuzumab). One proposed mechanism of trastuzumab resistance is proteolytic cleavage of erbB2 receptor from its full-length (p185) form into truncated, constitutively active p95. Increased expression of p95erbB2 correlates with increased nodal involvement and poor clinical outcome. Because p95erbB2 lacks the trastuzumab binding epitope, expression may designate patients who would be suitable for treatment with erbB2 kinase inhibitors.Materials and Methods:Recombinant p185erbB2 and p95erbB2 constructs were stably expressed in several cell types via retroviral vector. Additionally, an intracellular form of p95erbB2 that arises via alternative translation and an intracellular p95erbB2 construct containing two copies of a nuclear localization sequence were also expressed. Expression and proper subcellular localization of constructs were confirmed by cell fractionation, western blot analysis and confocal microscopy. Transformation of human mammary epithelial (HMEC) and NIH3T3 cells by p185erbB2 and p95erbB2 isoforms was evaluated by anchorage independent growth using a quantitative fluorescent soft agar assay, and effects on migration and invasion of these cells were investigated by wound-healing and transwell assays. Cells transfected with oncogenic Ras or empty vector were used as positive and negative controls in these experiments.Results and Discussion:Recombinant p185erbB2 and p95erbB2 constructs were stably expressed in HMEC and NIH3T3 cells, and were correctly directed to the cell membrane; nuclear targeted intracellular p95erbB2 was correctly localized to the cell nucleus. Both p185 erbB2 and membrane-bound truncated p95erbB2 were sufficient to transform HMEC cells as compared to empty vector control transfected cells [mean fluorescence intensity empty vector control 2480 ± 464 (1 standard deviation); mean fluorescence intensity p185erbB2 9208 ± 2528, p= 0.0106; mean fluorescence intensity p95erbB2 6615 ± 1588, p= 0.0124)] as was the positive control oncogenic Ras (mean fluorescence intensity 4350 ± 433, p=0.0069). Interestingly, nuclear-targeted p95erbB2 was also sufficient to transform HMEC cells (mean fluorescence intensity 6492 ± 818, p=0.0018). These data support the hypothesis that truncated p95erbB2 species may be major pathogenic drivers in erbB2-amplified cancers. P95erbB2 therefore represents an attractive target for diagnosis and treatment of erbB2+ breast cancer.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3136.
Characterisation of 17q12-21 – Identification of Novel Therapeutic Targets.
Authors: Glynn R. , Miller N. , Alvarez Iglesias E. , Doolin O. , Newell J. , Kerin M. 
Published: December 2010

Abstract
Introduction: Over-expression of the HER2/neu oncogene is associated with poorer clinical outcome in breast cancer. Notwithstanding the success achieved with Trastuzumab in treating HER2/neu positive patients, numerous questions remain. In particular, there are concerns regarding accurate identification of HER2/neu positivity and the correct management of these patients in terms of the dosage, timing and optimal combination of Trastzumab with chemotherapeutic regimens. One approach to answering these questions has been to focus on the area of chromosome 17 in which HER2/neu is located in order to identify other genes in the vicinity. As potential therapeutic targets, we examined the amplification and expression patterns of co-localised cancer-associated genes at the HER2/neu amplicon on chromosome 17.Aims: The primary objective of this study was to examine amplification and expression patterns of co-localised genes at 17q12-21. In doing so, we aimed to establish their relationship with HER2/neu positivity, and then to quantify their relative importance in developing a gene panel predictive of HER2/neu status.Methods: Breast tissue from a cohort of patients with HER2/neu positive (n=48) and negative (n=48) tumours was retrieved at time of surgery. Protein and gene expression levels were determined using immunohistochemistry and RQ-PCR, respectively. Results were analysed to detect patterns of amplification among the genes, namely HER2/neu, STARD3, GRB7, TOP2A, TUBG1, RPL19, LASP1, RARA, and ER Alpha, and to identify associations between expression levels and clinical data. A binary logistic approach and classification tree analysis was employed to determine whether the expression levels of our target genes were useful predictors of HER2/neu status.Results: Strong correlation was noted between expression levels of HER2/neu and multiple cancer-associated genes at 17q12-21, including the novel genes LASP1 (p=0.000) and RPL19 (p=0.000). A significant relationship was also noted between TOP2A and the previously unexplored TUBG1 (p=0.000). Analysis of gene expression patterns according to clinicopathological variables revealed significant associations across intrinsic breast cancer subtypes.Conclusion: This study reaffirms the correlation between HER2/neu and its co-localised genes at 17q12-21, including novel candidate genes LASP1 and RPL19. We have also identified a novel relationship between TOP2A and TUBG1. Furthermore, our work represents a tentative step in the development of more accurate means of characterising HER2/neu status. As such, this work has again indicated the central role which this amplicon may play in selection of patients for treatment, not alone for Herceptin and anthracyclines, but also for taxane-based therapies, and as such, has revealed novel pathways for us to follow as we move towards our goal of individually tailored therapy.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3137.
Distinctive Expression of Cancer/Testis-X Antigens in a Subset of ER Negative Breast Carcinomas.
Authors: Grigoriadis A. , Caballe O. , Hoek K. , da Silva L. , Chen Y. , Shin S. , Jungbluth A. , Miller L. , Cebon J. , Old L. , Lakhani S. , Simpson A. , Neville M. 
Published: December 2010

Abstract
Background: Cancer/testis-X antigens are a multigene family that are predominantly expressed in human germ line cells, with little or no expression in somatic adult tissues, but become aberrantly activated in various malignancies. Some such CT-X antigens represent ideal targets for cancer immunotherapy and have already been used in clinical testing. In contrast to melanomas, bladder, lung, ovarian and hepatocellular carcinomas which show higher levels of CT-X antigen expression, the reports in breast cancers have been inconclusive to date and a comprehensive gene expression and clinicopathological analysis has yet to be performed.Material and Methods: Using sequencing data as well as nine publicly available gene expression data sets, we analyzed the expression of Cancer/testis-X antigens in more than 1900 primary breast cancers. Complementary analysis was performed on three tissue microarrays comprising a total of 201 primary breast carcinomas and 53 brain metastases. Clinical information on the ER-, PR-, HER2, Ki67, p53, EGFR and basal markers was available for statistical analysis.Results: A significantly higher expression of Cancer/testis-X antigens was found in ER negative breast carcinomas over different data sets with a concordant gene expression pattern of several Cancer/testis-X antigens. Members of the MAGEA family and NY-ESO-1/CTAG1B were consistently the most prevalent. Immunohistochemical analyses confirmed a significant correlation of MAGEA family and NY-ESO-1/CTAG1B with ER negative (pValue &lt; 0.0001), PR negative (pValue &lt; 0.01) and Ki67 staining (pValue &lt; 0.0001). Many of these tumors were also positive for basal markers.Discussion: Previous studies of Cancer/testis-X antigens in breast have focused on ER positive cancers, in smaller subsets and provided inconclusive results. Using comprehensive gene expression data sets and tissue microarrays, we have demonstrated a significant association of MAGEA family and NY-ESO-1/CTAG1B with ER/PR negative breast cancer. Since these cancers represent a subgroup for which less therapeutic modalities are available, we propose the use of MAGEA and NY-ESO-1/CTAG1B cancer vaccines in the adjuvant setting as an approach to restricting tumor growth and metastases. Clinical trails using MAGEA and NY-ESO-1/CTAG1B are warranted.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3139.
Role of miR-143 Regulating DNA Methyltransferases 3A in Breast Cancer.
Authors: Ng E. , Kwong A. , Tsang W. , Leung C. , Wong C. , Kwok T. , Ma E. 
Published: December 2010

Abstract
Background and Aims: MicroRNAs (miRNAs) are 19-25-nucleotides regulatory non-protein-coding RNA molecules that regulate the expressions of a wide variety of genes including some involved in cancer development. In particular, decreased expression of miR-143 has been reported in various human cancers including colorectal cancer and B-cell lymphomas. The aim of this study was to elucidate the role of miR-143 dysregulation in breast cancer.Methods: Expression levels of human mature microRNAs (miRNAs) were compared with paired breast carcinomas and adjacent normal tissues by TaqMan real-time PCR based expression arrays. Decreased expression of miR-143 was further confirmed in breast cancer cell lines and paired breast tumors and normal adjacent tissues by qRT-PCR. Potential targets of miR-143 were defined. The functional effect of miR-143 and its targets was performed in human breast cancer cell lines to confirm target association.Results: Down-regulation of miR-143 was verified in both human breast cancer cell lines and 80% (12/15) of breast tumors (P &lt; 0.001). DNA methyltranferase 3A (DNMT3A), one of a key enzyme involved in DNA methylation, was defined as a potential target of miR-143 by in-silico analysis. Overexpression of miR-143 in breast cancer cell lines down-regulated expression of DNMT3A, decreased tumor cell growth by MTT assay and soft agar colony formation assay. DNMT3A was demonstrated to be a direct target of miR-143 by luciferase reporter assay. Inverse correlation between DNMT3A protein and miR-143 was found in tumor and normal breast tissues.Conclusions: In this study, we show for the first time in breast cancer that miR-143 specifically targeted DNMT3A and the expression of miR-143 was inversely correlated with DNMT3A expression. Our findings demonstrated that down-regulation of miR-143 and up-regulation of DNMT3A are significant changes in breast tumors. These findings indicate a tumor suppressive role of miR-143 in epigenetic aberration of breast cancer.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3148.
Downregulation of the Novel Candidate Tumor Suppressor Gene NCOR2/SMRT in Human Breast Cancer Progression.
Authors: Geradts J. , Saxena R. , Groth J. , Desouki M. , Burchette J. , Liao S. 
Published: December 2010

Abstract
Background: We recently described a number of DNA copy number changes that differentiated low grade ductal carcinoma in situ (DCIS) lesions with and without associated invasive carcinoma. One of the invasion-associated candidate genes was Nuclear Corepressor 2/Silencing Mediator of Retinoid and Thyroid Receptors (NCOR2/SMRT). This gene is a component of a repressing nuclear receptor complex and a mediator of ER activity. It facilitates recovery from DNA double strand breaks. Previous studies showed that downregulation of the gene was associated with transformation of non-Hodgkin lymphomas.Materials and Methods: Genomic DNA was extracted from microdissected paraffin sections of formalin fixed low grade DCIS lesions with an invasive component (n=42), as well as morphologically similar DCIS lesions without associated invasion within at least 5 years (n=38). Comparative PCR was performed with GAPDH as the reference gene. In addition, we assayed tissue microarrays (TMAs) by immunohistochemistry using two anti-Smrt antibodies. Three TMAs included 162 interpretable cases of invasive breast carcinoma from Roswell Park Cancer Institute (RPCI). One additional TMA included 73 interpretable breast cancers from a previously described cohort from Vienna, Austria. Nuclear staining in neoplastic cells was scored as positive, reduced (significantly weaker compared to admixed benign cells), and negative. Ncor2/Smrt expression was correlated with various patho-biologic variables.Results: Allelic loss of NCOR2/SMRT was observed in 79% (33/42) of DCIS lesions with associated invasion, but in only 26% (10/38) of pure DCIS cases (p&lt;0.01). In the RPCI breast cancer cohort, nuclear Ncor2/Smrt protein was absent or downregulated in 73% (119/162) of tumors. In the Vienna cohort, there was no or markedly reduced nuclear staining in 48% (35/73) of cases. In both cohorts, loss of nuclear reactivity was more common in ER-negative breast cancers. In the Vienna series, Ncor2/Smrt loss was more frequent in PR-negative tumors as well. In the RPCI cohort, Ncor2/Smrt downregulation was more common in ductal (81%, 109/135) than in lobular (37%, 10/27) carcinomas. Neither series showed a significant association between Ncor2/Smrt expression and tumor grade or HER2/neu status.Discussion: Allelic loss of NCOR2/SMRT was significantly more common in DCIS lesions associated with stromal invasion. In invasive tumors, the protein downregulation rate was between 48% and 73%. The gene was more commonly downregulated in ER-negative carcinomas, consistent with its role as a modulator of ER function. Our data provide new evidence that NCOR2/SMRT may play an important part in early breast cancer progression.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3150.
Constitutive Activation of Smoothened (SMO) Enhances MMTV-c-ErbB2-Induced, but Not MMTV-Wnt1-Induced, Mammary Tumorigenesis.
Authors: Landua J. , Moraes R. , Li Y. , Lewis M. 
Published: December 2010

Abstract
Background. Smoothened (Smo) is a key effector protein in the hedgehog signaling pathway, a developmental pathway involved in the regulation of pattern formation, proliferation, cell fate, and stem/progenitor cell function in the mammary gland. In human clinical samples, altered hedgehog signaling occurs early in breast cancer development with SMO ectopically expressed in 70% of DCIS and 30% of IBC. Coupled with our genetic studies in mice, these clinical observations suggest a causal or contributory role in breast cancer.Materials and Methods. To determine whether activation of SMO is oncogenic in the mammary gland, and to study possible interactions between hedgehog signaling and other oncogenic signaling pathways, we crossed transgenic mice expressing a constitutively active form of Smo (SmoM2) under the Mouse Mammary Tumor Virus promoter (MMTV-SmoM2) with mice expressing either MMTV-Wnt1 or MMTV-c-ErbB2. Time to tumor onset, tumor growth, and tumor multiplicity were measured, and resulting tumors evaluated histologically.Results. Expression of MMTV-SmoM2 was not oncogenic as a single genetic alteration. In genetic crosses, simultaneous expression of MMTV-Wnt1 and MMTV-SmoM2 within mammary epithelium did not affect tumor formation. However, simultaneous expression of MMTV-c-ErbB2 and MMTV-SmoM2 resulted in significantly accelerated median time to tumor formation, with an overall tumor formation rate of 100% compared to MMTV-c-ErbB2 alone (74%).Discussion. Activated SMO is not oncogenic under the conditions tested. However, MMTV-SmoM2 interacts genetically with MMTV-c-ErbB2, but not MMTV-Wnt1 to promote mammary tumorigenesis. Together, our data indicate a contributory role for Smo in breast cancer progression and suggest that hedgehog signaling inhibitors may be useful for treatment of a subset of human breast cancers.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3152.
Cellular Location and Expression Pattern of NHERF1 in Human Breast Cancer and the Impact of NHERF1 on the Growth of Breast Cancer Cells.
Authors: Cheng S. , Cheng S. , He J. , Martin T. , Ye L. , Mansel R. , Jiang W. 
Published: December 2010

Abstract
BACKGROUND: The Na+/H+ exchange regulatory factor 1 (NHERF1) is an adapter protein that, when present in the cytoplasmic region, regulates trafficking and signaling of several G protein-coupled receptors (GPCRs). However, it has been recently suggested that, when located in the nucleus of cells, NHERF1 may have an oncogenic role in cancer. Recent work has shown that NHERF1 may be involved in the progression of certain solid tumours including breast cancer. The aim of the current study were: first to evaluate the spatial and cellular location of the NHEREF1 protein in mammary tissues, mammary epithelial and cancer cells, second to determine the expression pattern of the NHERF1 transcript in human breast cancer and deduce a possible association with clinical and pathological factors and, finally, to investigate the cellular impact of NHERF1 expression on breast cancer cells.MATERIALS AND METHODS: Expression of NHERF1 was examined in a cohort of breast tissue samples. The protein levels and distributions were assessed using immunohistochemical staining (IHC) and imaging analysis tools. The distribution of the NHERF1 protein in nucleus and cytoplasm was calculated using the protein staining intensity ratio between the two compartments. The transcript level was determined using quantitative real time-PCR. Constructed ribozyme transgenes were used to knock-down NHERF1 in MCF-7 cells, and the effect this had on in vitro cell growth was examined using in vitro methods.RESULTS: NHERF1 protein staining was seen in both normal epithelial cells and cancer cells in tissues. However, the staining pattern in cancer cells and normal epithelial cells was different. The protein was seen at a higher level in the nucleaus of cancer cells, as shown by a higher nuclear/cytoplasmic ratio of NHERF1 staining in breast cancer cells when compared with that in normal mammary epithelial cells (p=0.038). NHERF1 expression was increased in high grade tumours compared with low grade tumours (p=0.0016, grade-3 vs grade-1). Quantitative analysis of the NHERF1 transcript revealed a higher level expression in samples from patients with poor prognosis and that this was linked to the long term survival: mean survival for patients with high NHERF1 was 102 (55-148.8, 95%CI) months compared with 136 (126.6-145.9) months for patients with low NHERF1 transcripts. Using human breast cancer cell line, MCF7, we created NHERF1 knockdown subline. Loss of NHERF1 in the MCF-7 subline resulted in an increase in the growth rate, in vitro.CONCLUSION: This study shows that NHERF1 influences the growth of breast cancer cells. However, the effect of NHERF1 is dependent upon the levels of expression of NHERF1 in breast cancer tissues and most importantly determined by the cellular location of this protein in cancer cells.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3155.
Suppressors of Cytokine Signaling and Their Role in Human Breast Cancer.
Authors: Sasi W. , Jiang W. , Sharma A. , Mokbel K. 
Published: December 2010

Abstract
BACKGROUND:Suppressors of cytokine signaling (SOCS) are important negative feedback regulators of the JAK/STAT signaling pathway, and have been recently investigated for their role in the development of different cancers. In this study, we examined the expression of SOCS 1-7 genes in normal and breast cancer tissue and correlated this with several clinico-pathological and prognostic factors.PATIENTS AND METHODS:SOCS 1-7 mRNA extraction and reverse transcription were performed on breast cancer tissue samples (n= 127) and normal background breast tissue (n= 31). Transcript levels of expression were determined using real-time PCR and analyzed against TNM stage, tumour grade and clinical outcome over a 10 year follow-up period.RESULTS:SOCS 1,4,5,6 and 7 expression decreased with increased TNM stage (TNM1 vs. TNM3 p= 0.039, TNM1 vs. TNM4 p= 0.016, TNM1 vs. TNM3 p= 0.012 and TNM1 vs. TNM3 p= 0.044 respectively). SOCS 2 and 3 expression decreased with increased Nottingham Prognostic Index (NPI) (NPI1 vs. NPI3 p=0.033 and NPI2 vs. NPI3 p=0.041 respectively). SOCS-7 expression decreased with higher tumour grade (Grade 3 vs. Grade 2 p=0.037). After a median follow up period of 10 years, we found higher levels of SOCS 1, 2 and 7 expression among those patients who remained disease-free compared to those who developed local recurrence (p= 0.0073, p= 0.021 and p= 0.039 respectively). Similarly, we found higher levels of SOCS 2, 4 and 7 expression in those who remained disease-free compared to those who developed distant recurrence (p= 0.022, p=0.024 and p= 0.033 respectively). Patients who remained disease-free had higher levels of SOCS 1 and 2 expression compared to those who died from breast cancer (p= 0.02 and p=0.033 respectively). The disease free survival (DFS) and overall survival (OS) curves showed that higher levels of SOCS 1, 3 and 7 were significant predictors of higher DFS (p=0.015, p=0.024 and p=0.03 respectively) and OS (p=0.005, p=0.013 and p= 0.035 respectively). Higher levels of SOCS 4 were significant in predicting better OS (p=0.007) but not DFS.CONCLUSIONHigher mRNA expression levels of SOCS 1, 3, 4 and 7 are significantly associated with earlier tumour stage and better clinical outcomes in human breast cancer.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3157.