Stages Of Invasive Ductal Carcinoma Research Articles

MicroRNA signatures differentiate types, grades, and stages of breast invasive ductal carcinoma (IDC): miRNA-target interacting signaling pathways

BackgroundInvasive ductal carcinoma (IDC) is the most common form of breast cancer which accounts for 85% of all breast cancer diagnoses. Non-invasive and early stages have a better prognosis than late-stage invasive cancer that has spread to lymph nodes. The involvement of microRNAs (miRNAs) in the initiation and progression of breast cancer holds great promise for the development of molecular tools for early diagnosis and prognosis. Therefore, developing a cost effective, quick and robust early detection protocol using miRNAs for breast cancer diagnosis is an imminent need that could strengthen the health care system to tackle this disease around the world.MethodsWe have analyzed putative miRNAs signatures in 100 breast cancer samples using two independent high fidelity array systems. Unique and common miRNA signatures from both array systems were validated using stringent double-blind individual TaqMan assays and their expression pattern was confirmed with tissue microarrays and northern analysis. In silico analysis were carried out to find miRNA targets and were validated with q-PCR and immunoblotting. In addition, functional validation using antibody arrays was also carried out to confirm the oncotargets and their networking in different pathways. Similar profiling was carried out in Brca2/p53 double knock out mice models using rodent miRNA microarrays that revealed common signatures with human arrays which could be used for future in vivo functional validation.ResultsExpression profile revealed 85% downregulated and 15% upregulated microRNAs in the patient samples of IDC. Among them, 439 miRNAs were associated with breast cancer, out of which 107 miRNAs qualified to be potential biomarkers for the stratification of different types, grades and stages of IDC after stringent validation. Functional validation of their putative targets revealed extensive miRNA network in different oncogenic pathways thus contributing to epithelial-mesenchymal transition (EMT) and cellular plasticity.ConclusionThis study revealed potential biomarkers for the robust classification as well as rapid, cost effective and early detection of IDC of breast cancer. It not only confirmed the role of these miRNAs in cancer development but also revealed the oncogenic pathways involved in different progressive grades and stages thus suggesting a role in EMT and cellular plasticity during breast tumorigenesis per se and IDC in particular. Thus, our findings have provided newer insights into the miRNA signatures for the classification and early detection of IDC.

Identification of prognostic biomarkers of invasive ductal carcinoma by an integrated bioinformatics approach

Background: Invasive ductal carcinoma (IDC) is the most common breast cancer worldwide. Nowadays, due to IDC heterogeneity and its high capacity for metastasis, it is necessary to discover novel diagnostic and prognostic biomarkers. Thus, this study aimed to identify new prognostic genes of IDC using an integrated bioinformatics approach. Methods: Using the Gene Expression Omnibus (GEO) database, we downloaded publicly available data of the whole-genome mRNA expression profile from the first three stages of IDC in two expression profiling datasets, GSE29044 and GSE32291; intra-group data repeatability tests were conducted using Pearson’s correlation test, and the differentially expressed genes (DEGs) were identified using the online tool GEO2R, followed by the construction of a protein‑protein interaction network (PPI-net) with the common DEGs identified in the three analyzed stages using the Search Tool for the Retrieval of Interacting Genes (STRING) database and Cytoscape software, from these PPI-net we identify the hub genes (prognostic genes). Results: We found seven genes [WW domain-containing E3 ubiquitin-protein ligase 1 (WWP1), STIP1 homology and U-box containing protein 1 (STUB1), F-box and WD repeat domain containing 7 (FBXW7), kelch like family member 13 (KLHL13), ubiquitin-conjugating enzyme E2 Q1 (UBE2Q1), tripartite motif-containing 11 (TRIM11), and the beta-transducin repeat containing E3 ubiquitin-protein ligase (BTRC)] as potential candidates for IDC prognostic biomarkers, which were mainly enriched in the Ubiquitin-specific protease activity, cytoskeletal protein binding, and ligase activity. The role of these genes in the pathophysiology of IDC is not yet well characterized, representing a way to improve our understanding of the process of tumorigenesis and the underlying molecular events of IDC. Conclusions: Genes identified may lead to the discovery of new prognostic targets and precise therapeutics for IDC.

Effect of Multimodal Exercise Program on Functional Outcome, Fatigue and Emotional Health in Mastectomy Patient with Concomitant Rheumatoid Arthritis: A Case Study

Breast cancer is among the most prevalent type of cancer among women. Mastectomy is a common surgical option for breast cancer, which usually leads to significant functional impairment. Fatigue, anxiety and depression are reported by mastectomy patients. This study aims to investigate the effect of a multimodal exercise program on improving functional impairment, fatigue, anxiety and depression after mastectomy. A 40-year-old female presented with abnormal tissue growth, pain and nipple discharge at the right breast. She was diagnosed with invasive ductal carcinoma stage I and undertook six weeks of neoadjuvant chemotherapy followed by modified radical mastectomy (MRM). Postoperatively, patient had a functional impairment, fatigue, anxiety and depression. An eight-week multimodal exercise program comprising ROM exercises, strength and endurance training, breathing exercises and functional activities was given. DASH for assessing upper extremity functions, BFI for assessing the impact of fatigue on daily activities and HADS for assessing anxiety and depression. An eight-week multimodal exercise program effectively improves functional impairment, fatigue, anxiety and depression in mastectomy patients with rheumatoid arthritis.

Histopathological Grading and Staging of Invasive Ductal Carcinoma in Modified Radical Mastectomy Specimens

Background: Breast carcinoma is the most common malignancy in females associated with high mortality rate. Objective: The purpose of present study was to describe the histological grade and histopathological stage of invasive ductal carcinoma of breast among female patients and to determine the association of tumor size and histological grade withnodal metastasis. Methods: This is an analytical cross sectional study, conducted in the Department of Pathology Fatima Jinnah Medical University Lahore, Pakistan from September, 2019 till February, 2020. Female patients of all age groups who were diagnosedwith invasive ductal carcinoma and underwent modified radical mastectomy were included in the study. Tissue processed and Hematoxylin and Eosin staining was performed. All the sections were examined under the light microscope by myself and two other consultant pathologists independently. Histological grading of invasive ductal carcinoma was done by following Modified Scarff Bloom Richardson grading system and histopathological staging was done according to CAP protocols. Results: Total of 60 female patients diagnosed with invasive ductal carcinoma were included in the present study. Mean age of the patient calculated was 48.17± 13.12 years with age range from 26 to 90 years. Size of the tumor ranged from 1cm to 10cm. On microscopy, histological grade III was the most frequent grade (36, 60%). Out of total 60 cases n=43(71.6%) were diagnosed with regional lymph node metastasis and T2N1Mx( 17,38.3%) was the most frequent stage of the tumor. Statistically no significant association of tumor size and histological grade was observed with regional lymph node metastasis (p >0.05).

Sharp Downregulation of Hub Genes Associated With the Pathogenesis of Breast Cancer From Ductal Carcinoma In Situ to Invasive Ductal Carcinoma.

IntroductionBreast atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS) are precursor stages of invasive ductal carcinoma (IDC). This study aimed to investigate the pathogenesis of breast cancer by dynamically analyzing expression changes of hub genes from normal mammary epithelium (NME) to simple ductal hyperplasia (SH), ADH, DCIS, and finally to IDC.MethodsLaser-capture microdissection (LCM) data for NME, SH, ADH, DCIS, and IDC cells were obtained. Weighted gene co-expression network analysis (WGCNA) was performed to dynamically analyze the gene modules and hub genes associated with the pathogenesis of breast cancer. Tissue microarray, immunohistochemical, and western blot analyses were performed to determine the protein expression trends of hub genes.ResultsTwo modules showed a trend of increasing expression during the development of breast disease from NME to DCIS, whereas a third module displayed a completely different trend. Interestingly, the three modules displayed inverse trends from DCIS to IDC compared with from NME to DCIS; that is, previously upregulated modules were subsequently downregulated and vice versa. We further analyzed the module that was most closely associated with DCIS (p=7e−07). Kyoto Gene and Genomic Gene Encyclopedia enrichment analysis revealed that the genes in this module were closely related to the cell cycle (p= 4.3e–12). WGCNA revealed eight hub genes in the module, namely, CDK1, NUSAP1, CEP55, TOP2A, MELK, PBK, RRM2, and MAD2L1. Subsequent analysis of these hub genes revealed that their expression levels were lower in IDC tissues than in DCIS tissues, consistent with the expression trend of the module. The protein expression levels of five of the hub genes gradually increased from NME to DCIS and then decreased in IDC. Survival analysis predicted poor survival among breast cancer patients if these hub genes were not downregulated from DCIS to IDC.ConclusionsFive hub genes, RRM2, TOP2A, PBK, MELK, and NUSAP1, which are associated with breast cancer pathogenesis, are gradually upregulated from NME to DCIS and then downregulated in IDC. If these hub genes are not downregulated from DCIS to IDC, patient survival is compromised. However, the underlying mechanisms warrant further elucidation in future studies.

Classification models for Invasive Ductal Carcinoma Progression, based on gene expression data-trained supervised machine learning

Early detection of breast cancer and its correct stage determination are important for prognosis and rendering appropriate personalized clinical treatment to breast cancer patients. However, despite considerable efforts and progress, there is a need to identify the specific genomic factors responsible for, or accompanying Invasive Ductal Carcinoma (IDC) progression stages, which can aid the determination of the correct cancer stages. We have developed two-class machine-learning classification models to differentiate the early and late stages of IDC. The prediction models are trained with RNA-seq gene expression profiles representing different IDC stages of 610 patients, obtained from The Cancer Genome Atlas (TCGA). Different supervised learning algorithms were trained and evaluated with an enriched model learning, facilitated by different feature selection methods. We also developed a machine-learning classifier trained on the same datasets with training sets reduced data corresponding to IDC driver genes. Based on these two classifiers, we have developed a web-server Duct-BRCA-CSP to predict early stage from late stages of IDC based on input RNA-seq gene expression profiles. The analysis conducted by us also enables deeper insights into the stage-dependent molecular events accompanying IDC progression. The server is publicly available at http://bioinfo.icgeb.res.in/duct-BRCA-CSP.

SUN-005 DAX-1 Inhibition of Estrogen Receptor and Metastasis Target Genes in Estrogen Receptor Positive Breast Cancer Cells

The association of estrogens with breast cancer has led to the development of drugs that block the action of estrogens to treat and prevent estrogen receptor (ER) positive tumors. However, many tumors eventually become resistant to these drugs. Future drug discovery requires the identification of novel targets in the ER signaling pathway. The identification of proteins that directly bind to ER may offer new therapeutic targets for the treatment of breast cancer. The orphan receptor, DAX-1 (Dosage Sensitive Sex Reversal Adrenal Hypoplasia Congenita on the X Chromosome, gene 1) has been shown to act as a corepressor of ERα actions in MCF7 breast cancer cells. In this study we investigated the expression of DAX-1 during progressive stages of invasive ductal carcinoma with known ER status. To define the effect of DAX-1 expression in ER positive breast cancer cells, we performed gene expression analysis using PCR arrays that were specific for human breast cancer gene targets, human estrogen receptor signaling targets and tumor metastasis targets. We found that adenovirus-mediated expression of DAX-1 inhibits MCF7 cell proliferation and blocks estradiol activation of specific ER target genes, including cyclin D1. Repression of the cyclin D1 gene in MCF7 cells is associated with the recruitment of DAX-1 to the cyclin D1 promoter. Furthermore, introduction of DAX-1 into MCF7 cells leads to cell cycle arrest and an increase in apoptosis. These results demonstrate that DAX-1 functions as a corepressor of ER action in MCF7 breast cancer cells by preventing the activation of growth promoting genes and decreasing the stimulation of cell proliferation in response to estrogens. These finding could have significant implications for future drug development strategies specifically aimed at ER interacting proteins such as DAX-1.

Identification of a gene signature for different stages of breast cancer development that could be used for early diagnosis and specific therapy.

Breast cancer (BC) is a heterogeneous disease where the survival rate of patients decreases with progression of the disease. BC usually has a linear progression, classified into normal/benign, atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS), and invasive ductal carcinoma (IDC). This study aimed to identify gene signature for each of these subgroups.We performed human transcriptome array analysis on 5 patient samples from each Normal, ADH, IDC and DCIS and 2 replicates of MCF10A cell line representative of each subgroup.We identified SFRP1 and snoRNAs (especially SNORD115 and SNORD114) as the initial regulators of cancer progression, accompanied by significant changes in extracellular matrix organization. Tumor progression to the IDC stage showed upregulation of tumor promoting genes responsible for increased invasion, inflammation, survival in stress environment and metastasis.The gene signatures identified in this study could represent potential biomarkers for each subgroup of breast cancer progression, which could assist in early diagnosis of breast cancer progression as well as treatment interventions. Moreover, these gene signatures could serve in discovery of specific targeted therapies for each subgroup.

Abstract 2248: Dynamic changes in transposon expression and epigenetic regulators detected during early breast cancer transition to malignancy

Abstract Introduction: Breast cancer is the second leading cause of cancer-related deaths in women. In 2017, about 315,000 women were diagnosed with breast cancer, with approximately 63,000 new cases of ductal carcinoma in situ (DCIS), the earliest form of breast cancer. Little is known as to why some patients diagnosed with atypia and DCIS remain cancer-free while others progresses to invasive ductal carcinoma (IDC). Hypothesis: While mutagenic role of transposonable elements (TEs) in cancer is known, we test the novel role of long terminal repeat (LTR) TEs as potential drivers promoting cell de-differentiation during early stages of breast cancer. Objective: To identify molecular signatures driving cell fate decisions at atypia and DCIS to transformation, we investigated expression of TEs in atypia, DCIS and IDC. Methods: We created a TE Enrichment Set Analysis (TESA) to identify TEs in RNA sequencing datasets across four stages of breast cancer, normal atypia, DCIS, IDC (n= 8-23 samples per stage). Results: After quality control steps to remove outliers, TEs, compared to genes, exhibit substantially less variation in their expression because the first principal component accounted for over 80% expression variation compared to 20% in transcript expression variation (p<0.05). Eighty-eight TEs were detected as significant across stages by ANOVA (α=0.05, FDR 5%). The majority of differentially expressed TEs were LTRs (67%, p<0.05) with the remaining split into DNA TEs (18%), SINEs (11%) and unclassified (4%). Despite being the largest TE portion in the human genome, no statistically significant differences were detected in LINEs (p>0.10). Six general patterns of TE expression were identified using k-means clustering algorithm. In general, the majority of TEs were upregulated during atypia or DCIS stages or both stages. To identify potential molecular mechanisms of TE de-repression, which induce LTR expression during atypia and DCIS, we measured the correlation between specific LTRs, including HERV-H, HERV-K, LTR7Y, and expression of epigenetic regulators, TETs, DNMTs, and TRIM28/KAP1 across all four stages. As expected, normal tissue has positive and negative correlations between LTRs and epigenetic regulators, however, at atypia there was a loss of some negative correlations and at DCIS all negative correlations between LTRs and DNMTS were lost (p<0.0001). Unexpectedly, at IDC stage, the negative correlations re-emerged between LTRs and DNMTs (p<0.05). Together, these data imply the epigenetic remodeling occurs prior to malignancy, which associates, and may potentially drive, LTR expression. Conclusion: Our TESA data provides experimental support that early genomic changes are a mechanism underlying malignancy. Translational bioinformatics is a technique to identify prognostic molecules for impending invasive breast cancer from biopsies from pre-malignant stages. Citation Format: Isaac D. Raplee, Alexei Evsikov, Caralina Marin de Evsikova. Dynamic changes in transposon expression and epigenetic regulators detected during early breast cancer transition to malignancy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2248.

Abstract LB-258: Orphan nuclear hormone receptor, DAX-1, expression during progressive stages of invasive ductal carcimona

Abstract The orphan nuclear hormone receptor DAX-1 (Dosage Sensitive Sex Reversal Adrenal Hypoplasia Congenita on the X Chromosome, gene 1) plays an important role in the development of adrenal and gonadal tissues and functions as a global negative-regulator of steroidogenesis. In addition, it is known to play a role in several cancers including breast. DAX-1 immunoreactivity had been found to directly correlate with androgen receptor (AR), estrogen receptor (ER) expression and lymph node metastasis. Beyond this, DAX-1’s role in breast cancer is relatively poorly understood. In this study we investigated, using fluorescent immunohistochemistry, the expression of DAX-1 and AR during progressive stages of invasive ductal carcinoma with known estrogen receptor ER status. Additionally correlations with patient age, tumor grade, TNM score, progesterone receptor (PR), antigen Ki67 expression and human epidermal growth factor receptor 2 (Her2), were analysed. Comparing both bioinformatic and protein staining methodology we attempted to correlate DAX-1, AR and ER to cancer stage. In order to understand the mechanisms involved in cancer progression we employed epigenetic studies to determine if changes in DAX-1 expression correlated to changes in methylation status. Our data suggests DAX-1 is expressed more frequently in early stage breast cancer. Understanding the time points and mechanisms by which DAX-1 acts in breast cancer could potentially provide a novel target for therapeutic treatments. Citation Format: Erin Dishington. Orphan nuclear hormone receptor, DAX-1, expression during progressive stages of invasive ductal carcimona [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-258. doi:10.1158/1538-7445.AM2017-LB-258

Abstract B28: Induced expression of Sprouty4 in breast invasive ductal carcinoma cells inhibits ERK MAP kinase and reduces malignant phenotype

Abstract Our previous work has identified increased expression of Sprouty4 in 3D models of breast ductal carcinoma in situ (DCIS). Sprouty4 in other systems has been shown to function as a negative regulator of the mitogen activated protein kinase (MAPK/ERK) pathway. We hypothesize that Sprouty4 is an endogenous inhibitor of ERK/MAPK signaling in DCIS, and that its loss or reduced expression is one mechanism by which triple-negative lesions progress toward invasive ductal carcinoma (IDC). Using immunohistochemistry our labs have found that Sprouty4 was highly expressed in some human premalignant breast tissue samples, and that this expression was reduced in malignant triple-negative samples. These results correspond with immunoblot data from our 3D culture model of breast cancer progression in which Sprouty4 expression was higher during DCIS than in the IDC stage. Efficient over-expression of Sprouty4 reduced both MAPK/ERK activity as well as the aggressive phenotype of MCF10.CA1d IDC cells. Immunofluorescence experiments done in IDC cells overexpressing Sprouty4 revealed relocation of E-cadherin back to the cell surface and the restoration of adherens junctions. To determine if these effects were due to changes in MAPK/ERK signaling, IDC cells were treated with MEK162, an allosteric MEK inhibitor. Nanomolar concentrations of drug restored an epithelial-like phenotype similar to that produced by Sprouty4 over-expression. From these data we conclude that Sprouty4 may act to control MAPK/ERK signaling in a subset of DCIS, thus limiting the progression of these premalignant breast cancers. Further, if in vivo data correspond with our in vitro work, this may argue for the investigation of MEK inhibitors as an adjunct treatment in triple-negative disease, where options are limited. Citation Format: Ryan M. Jackson, Ethan J. Brock, Seema Shah, Mansoureh Sameni, Bonnie F. Sloane, Quanwen Li, Raymond R. Mattingly. Induced expression of Sprouty4 in breast invasive ductal carcinoma cells inhibits ERK MAP kinase and reduces malignant phenotype. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Targeting the Vulnerabilities of Cancer; May 16-19, 2016; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(1_Suppl):Abstract nr B28.

Clinical significance of expression of PI3Kp110α in breast cancer

Objective: To study the clinical significance of PI3Kp110α expression in breast cancer. Methods: The expressions of PI3Kp110α, HER2, PTEN, p-Akt and Ki-67 in invasive ductal carcinoma (IDC), adjacent ductal carcinoma in situ (DCIS) and normal breast tissue were detected by immunohistochemistry in 102 cases of breast cancer. The expression of PI3Kp110α in IDC was compared with those in DCIS and normal breast tissues. Correlations between expression of PI3Kp110α and expression of HER2, PTEN, p-Akt and Ki-67 index in IDC were analyzed. Correlation between expression of PI3Kp110α and stage of IDC was studied as well. Results: In the normal breast tissues, there were 97 cases (95.1%) with low level and 5 cases (4.9%) with high level expression of PI3Kp110α. In the DCIS tissues, there were 67 cases (65.7%) with low level and 35 cases (34.3%) with high level expression of PI3Kp110α. In the IDC tissues, there were 14 cases (13.7%) with low level and 88 cases (86.3%) with high level expression of PI3Kp110α. The difference between expression of PI3Kp110α in normal breast tissue, DCIS and IDC was significant (P<0.001). In the IDC tissues, expression of PI3Kp110α was negatively correlated with expression of HER2 (rs=-0.213, P=0.032) and PTEN (rs=-0.197, P=0.047), while was not significantly correlated with expression of p-Akt (P=0.119) and Ki-67 index (P=0.636). In contrast, expressions of HER-2 and p-Akt were positively correlated with Ki-67 index (P=0.001, P=0.035), while expression of HER2 was not correlated with p-Akt (P=0.177). Expression of PI3Kp110α was negatively correlated with T stage and TNM stage (P=0.003, P=0.016), while not correlated with N stage and M stage(both P>0.05). Expression of HER-2 was positively correlated with T stage (P=0.037), while not correlated with N stage, M stage and TNM stage (P>0.05 for all). Neither Ki-67 index nor expression of PTEN and p-Akt (P=0.194) were correlated with T stage, N stage, M stage and TNM stage. Conclusions: Expression of PI3Kp110α plays an important role in oncogenesis and development of breast cancer. Based on the fact that expression of PI3Kp110α is negatively correlated with expression of HER2 and PTEN and with T stage and TNM stage, we may conclude that increased expression of PI3Kp110α is another independent pathway in breast cancer development, and breast cancer patients with high expression of PI3Kp110α may have a better prognosis.

Abstract 4560: Induced Sprouty4 expression in breast invasive ductal carcinoma cells downregulates ERK/MAPK activity and restores an epithelial-like phenotype

Abstract Breast cancer is one of the most common cancers in U.S. women, with approximately 25% of these cases being in situ disease. Sprouty proteins are currently recognized as important regulators of ERK/MAPK signaling, and have been studied in various cancer types. By employing RNA-seq, previous studies from our laboratories determined specific gene expression changes common to three models of ductal carcinoma in situ (DCIS)—MCF10.DCIS, SUM 102, and SUM 225—when compared to MCF10A cells (a model of non-transformed breast epithelium). All cell lines were grown in three-dimensional (3D) reconstituted basement membrane overlay culture because research has shown that the behavior of cancer cells in 3D matrices is more reflective of an in vivo response when exposed to drugs and radiotherapy than if they are cultured on plastic. Among the three models of DCIS, 63 genes were consistently upregulated. We identified 244 promoters associated with these 63 genes and performed bioinformatic data mining that revealed a high level of enrichment for a promoter framework shared by three of these genes: one of which encoded for the protein Sprouty4. We hypothesize that Sprouty4 is an endogenous inhibitor of ERK/MAPK signaling in DCIS, and its loss or reduced expression is a mechanism by which triple-negative lesions progress toward invasive ductal carcinoma (IDC). Using immunohistochemistry we found that Sprouty4 was highly expressed in certain human premalignant breast tissue samples, and that this expression was reduced in malignant triple-negative samples. These results correspond with immunoblot data from our 3D culture model of breast cancer progression in which Sprouty4 expression was higher during DCIS than in the IDC stage. Efficient over-expression of Sprouty4 reduced both ERK/MAPK activity as well as the aggressive phenotype of MCF10.CA1d IDC cells. Immunofluorescence experiments revealed data consistent with the relocation of E-cadherin back to the cell surface and the restoration of adherens. To determine if these effects were due to changes in ERK/MAPK signaling IDC cells were treated with MEK162, an allosteric MEK inhibitor. Nanomolar concentrations of drug produced a restoration of an epithelial-like phenotype similar to Sprouty4 over-expression. From these data we conclude that Sprouty4 may act to control ERK/MAPK signaling in a subset of DCIS, thus limiting the progression of these premalignant breast cancers. Citation Format: Ethan J. Brock, Ryan Jackson, Seema Shah, Quanwen Li, Mansoureh Sameni, Stephen A. Krawetz, Shihong Mao, Bonnie F. Sloane, Raymond R. Mattingly. Induced Sprouty4 expression in breast invasive ductal carcinoma cells downregulates ERK/MAPK activity and restores an epithelial-like phenotype. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4560.

Five Top Stories in Breast Pathology

Five Top Stories in Breast Pathology

Telomere fusions in early human breast carcinoma

Several lines of evidence suggest that defects in telomere maintenance play a significant role in the initiation of genomic instability during carcinogenesis. Although the general concept of defective telomere maintenance initiating genomic instability has been acknowledged, there remains a critical gap in the direct evidence of telomere dysfunction in human solid tumors. To address this topic, we devised a multiplex PCR-based assay, termed TAR (telomere-associated repeat) fusion PCR, to detect and analyze chromosome end-to-end associations (telomere fusions) within human breast tumor tissue. Using TAR fusion PCR, we found that human breast lesions, but not normal breast tissues from healthy volunteers, contained telomere fusions. Telomere fusions were detected at similar frequencies during early ductal carcinoma in situ and in the later invasive ductal carcinoma stage. Our results provide direct evidence that telomere fusions are present in human breast tumor tissue and suggest that telomere dysfunction may be an important component of the genomic instability observed in this cancer. Development of this robust method that allows identification of these genetic aberrations (telomere fusions) is anticipated to be a valuable tool for dissecting mechanisms of telomere dysfunction.

The molecular pathology of breast cancer progression.

The current model of human breast cancer progression proposes a linear multi-step process which initiates as flat epithelial atypia (FEA), progresses to atypical ductal hyperplasia (ADH), evolves into DCIS and culminates in the potentially lethal stage of invasive ductal carcinoma. For several decades a major challenge to human breast cancer research has been the identification of the molecular alterations associated with the different stages of breast cancer progression. Until recently, progress in attaining this goal has been hampered by technical limitations associated with applying advanced molecular technologies to the microscopic preinvasive stages of breast tumorigenesis. Recent advances in comprehensive, high-throughput genetic, transcriptomic and epigenetic technologies in combination with advanced microdissection and ex vivo isolation techniques have provided for a more complete understanding of the complex molecular genetic and molecular biological inter-relationships of the different stages of human breast cancer evolution. Here we review the molecular biological data suggesting that breast cancer develops and evolves along two distinct molecular genetic pathways. We also briefly review gene expression and epigenetic data that support the view of the tumour microenvironment as an important co-conspirator rather than a passive bystander during human breast tumorigenesis.

Abstract C243: B7-H4 protein expression in invasive ductal carcinoma and its association with tumor progression

Abstract High levels of B7-H4 (DD-O110) protein expression have been previously observed in malignant ductal epithelium of the breast but the mechanisms that mediate B7-H4 up-regulation in tumor progression have not yet been determined. An objective of our research has been to explore the differences in the levels of B7-H4 expression that underlie the transition from benign ductal epithelium to ductal carcinoma in situ (DCIS) and to the earliest stages of invasive ductal carcinoma. B7-H4 is a member of the B7 family of proteins which has been found to play a role in antigen-specific immune response regulation, including the regulation of T cell activation. The potential role of B7-H4 in tumor progression, or in shielding breast cancers from immune surveillance mechanisms, remains relatively unexplored. Previous immunohistochemical (IHC) studies have evaluated only a small subset of available B7-H4 antibody epitopes. The aim of the current study is to determine if there is differential expression of specific B7-H4 epitopes that are associated with benign versus proliferative and malignant breast disease. A panel of monoclonal antibodies to defined B7-H4 epitopes (diaDexus, Inc.) was evaluated in normal breast tissues versus invasive ductal carcinoma, using indirect immunoperoxidase methods, in sections of formalin fixed tissues. The patterns of B7-H4 localization of each antibody were compared with the patterns observed with the previously reported A57.1 antibody (Mugler et al., 2007). B7-H4 IHC scores were determined based on the intensity of staining (0 to 3+), the proportion of positive cells, and the cellular pattern of distribution (apical membranous versus circumferential membranous plus cytoplasmic). Preliminary data suggest that certain B7-H4 epitopes appear to have enhanced cancer selectivity, reflected by differential expression between normal ductal cells versus ductal carcinoma cells. Additionally, these studies confirm that there are differences in the subcellular distribution of B7-H4 expression, with low level, apical membranous expression in benign ductal epithelium and high level circumferential membranous expression in most well to moderately-differentiated ductal carcinomas. Furthermore, there appears to be a marked reduction in the levels of B7-H4 expression in some poorly differentiated carcinomas, despite normal levels of expression in adjacent benign ductal epithelial cells. These results suggest that B7-H4 overexpression may play a role in the progression from benign proliferative disease to low grade carcinomas. Further studies are indicated to refine the association of B7-H4 with tumor histologic grade and stage, and to elucidate the potential role of this protein in shielding breast carcinomas from cell-mediated immune surveillance. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):C243.

BigH3 protein expression as a marker for breast cancer

The current hypothesis of tumorigenesis in humans suggests that cancer cells acquire their hallmarks of malignancy through the accumulation of advantageous gene activation and inactivation events over long periods of time. For breast cancer development, this multistep process may manifest itself as a sequence of pathologically defined stages. It is widely held that breast cancer originates at the premalignant stage of atypical ductal hyperplasia, progresses to the preinvasive stage of ductal carcinoma in situ, and culminates in the potentially lethal stage of invasive ductal carcinoma. Tumor grade has been a highly valuable prognostic factor for breast cancer, and high-grade ductal carcinoma in situ lesions are associated with poor clinical outcome. The aim of this work was to investigate the BigH3 protein expression changes associated with various stages of breast cancer progression in comparison to benign specimens using tissue microarray technology. Pathological characteristics of breast tissues ranged from benign lesions to breast cancers either of lobular or ductal carcinomas in origin, and included in situ ductal carcinomas, lobular carcinomas, infiltrating ductal carcinomas, carcinomas, scirrhous carcinomas, adenocarcinomas and infiltrating colloid carcinomas. BigH3 protein expression was analyzed by immunohistochemistry in 192 cases of breast tumors. Results indicated a decrease in BigH3 protein expression from benign tissues to in situ ductal carcinoma, lobular carcinoma, infiltrating ductal carcinomas, carcinomas, scirrhous carcinoma, adenocarcinomas to infiltrating colloid carcinomas. We observed that the benign tissue had a 23-fold increase in BigH3 protein expression compared to the infiltrating colloid carcinoma which was the most malignant tissue analyzed. In summary, these studies confirmed the suppressor effect of the BigH3 gene expressed as protein expression in those processes related to the progression of breast tumorigenesis. We conclude that this protein can be used as a marker for breast cancer progression.