Marker For Breast Cancer Progression Research Articles

Peripheral blood TCR clonotype diversity as an age-associated marker of breast cancer progression.

Immune escape is a prerequisite for tumor growth. We previously described a decline in intratumor activated cytotoxic T cells and T cell receptor (TCR) clonotype diversity in invasive breast carcinomas compared to ductal carcinoma in situ (DCIS), implying a central role of decreasing T cell responses in tumor progression. To determine potential associations between peripheral immunity and breast tumor progression, here, we assessed the peripheral blood TCR clonotype of 485 breast cancer patients diagnosed with either DCIS or de novo stage IV disease at younger (<45) or older (≥45) age. TCR clonotype diversity was significantly lower in older compared to younger breast cancer patients regardless of tumor stage at diagnosis. In the younger age group, TCR-α clonotype diversity was lower in patients diagnosed with de novo stage IV breast cancer compared to those diagnosed with DCIS. In the older age group, DCIS patients with higher TCR-α clonotype diversity were more likely to have a recurrence compared to those with lower diversity. Whole blood transcriptome profiles were distinct depending on the TCR-α Chao1 diversity score. There were more CD8+ T cells and a more active immune environment in DCIS tumors of young patients with higher peripheral blood TCR-α Chao1 diversity than in those with lower diversity. These results provide insights into the role that host immunity plays in breast cancer development across different age groups.

Proteomic analysis of circulating extracellular vesicles identifies potential markers of breast cancer progression, recurrence, and response.

Proteomic profiling of circulating small extracellular vesicles (sEVs) represents a promising, noninvasive approach for early detection and therapeutic monitoring of breast cancer (BC). We describe a relatively low-cost, fast, and reliable method to isolate sEVs from plasma of BC patients and analyze their protein content by semiquantitative proteomics. sEV-enriched fractions were isolated from plasma of healthy controls and BC patients at different disease stages before and after surgery. Proteomic analysis of sEV-enriched fractions using reverse phase protein array revealed a signature of seven proteins that differentiated BC patients from healthy individuals, of which FAK and fibronectin displayed high diagnostic accuracy. The size of sEVs was significantly reduced in advanced disease stage, concomitant with a stage-specific protein signature. Furthermore, we observed protein-based distinct clusters of healthy controls, chemotherapy-treated and untreated postsurgery samples, as well as a predictor of high risk of cancer relapse, suggesting that the applied methods warrant development for advanced diagnostics.

Stromal Markers of Breast Cancer Progression: A Review of Recent Findings

Breast cancer research has long focused on breast epithelium in cancer development. This traditional view is being challenged by more recent work which suggests that stromal components such as fibroblasts, immune cells, endothelial cells, and others may play a central role in cancer development. The purpose of this review is to investigate the elements of the breast stroma and their interaction with the epithelium in creating the necessary pro-tumorigenic environment. Several studies have revealed that breast cancer stroma differs significantly from normal breast stroma, with altered cellular and molecular factors that may serve as potential therapeutic targets in breast cancer treatment. Studies of the complex interactions within the cancer ecosystem have revealed tumor-associated stromal changes that promote cell growth and invasiveness. They also reveal specific targets for novel strategies to inhibit inflammation, immunosuppression, angiogenesis, and distant invasion.

Apical cell protrusions cause vertical deformation of the soft cancer nucleus.

Breast cancer nuclei have highly irregular shapes, which are diagnostic and prognostic markers of breast cancer progression. The mechanisms by which irregular cancer nuclear shapes develop are not well understood. Here we report the existence of vertical, apical cell protrusions in cultured MDA-MB-231 breast cancer cells. Once formed, these protrusions persist over time scales of hours and are associated with vertically upward nuclear deformations. They are absent in normal mammary epithelial cells (MCF-10A cells). Microtubule disruption enriched these protrusions preferentially in MDA-MB-231 cells compared with MCF-10A cells, whereas inhibition of nonmuscle myosin II (NMMII) abolished this enrichment. Dynamic confocal imaging of the vertical cell and nuclear shape revealed that the apical cell protrusions form first, and in response, the nucleus deforms and/or subsequently gets vertically extruded into the apical protrusion. Overexpression of lamin A/C in MDA-MB-231 cells reduced nuclear deformation in apical protrusions. These data highlight the role of mechanical stresses generated by moving boundaries, as well as abnormal nuclear mechanics in the development of abnormal nuclear shapes in breast cancer cells.

PO-267 PHGDH and PSAT confer metabolic vulnerability to IDH2-driven reprogramming in breast cancer

IntroductionReprogrammed energy metabolism is one among the distinguished cancer hallmarks that unravels the dysregulated bioenergetics of cancer cells. Isocitrate dehydrogenase 2 (IDH2), a mitochondrial metabolic enzyme has been reported to be overexpressed in several cancers, yet the mechanisms of wildtype IDH2-induced transformation are still obscure. We previously identified IDH2, as a novel poor prognosis marker of breast cancer progression. In agreement, transcriptomics (TCGA) and proteomics data of breast cancer clinical samples showed similar expression changes of increased wildtype IDH2 from luminal, to triple-negative and to HER-2 positive, which correlated with tumour aggressiveness.Material and methodsWe performed intracellular metabolite tracing with heavy labelled glucose (13C6) and glutamine (13C5) followed by ultra-high performance liquid chromatography separation and mass spectrometric analysis on the Q-Exactive Plus instrument. Genome-scale metabolic modelling analysis was performed to identify the IDH2-dependent metabolic genes using Minimization of Metabolic Adjustment (MOMA) algorithm.Results and discussionsOverexpression of IDH2 increased serine biosynthesis, increased glycolytic rate and oxidative stress resistance. Genome-scale metabolic modelling of breast cancer tumour data identified dependence on serine biosynthesis as one of the metabolic vulnerability of IDH2 overexpressing cells. CRISPR-Cas9 mediated knockout of phosphoglycerate dehydrogenase (PHGDH) and phosphoserine aminotransferase (PSAT) specifically inhibited IDH2 overexpressing cells, even in the presence of exogenous serine and glycine, and reduced the glycolysis rate and glucose uptake. Furthermore, loss of serine synthesis pathway hampered the flux from glycolysis, into the TCA cycle. Moreover the metabolic perturbations of synthetic dosage lethal partners, PHGDH and PSAT sensitised the IDH2 overexpressing cells to oxidative stress.ConclusionThis study reveals WT-IDH2 as a critical metabolic regulator in breast cancer that supports the pro-tumorigenic Warburg effect. These findings may contribute to translate the metabolic dependency to improve targeted therapeutics.

Abstract 4680: H3K9 methyltransferase G9a epigenetically regulates breast cancer cell iron homeostasis via repressing ferroxidase hephaestin expression, promotes breast cancer growth

Abstract G9a is a H3K9 methyltransferase with elevated expression observed in many types of human cancers, seems to be required for the maintenance of the malignant phenotype. However, the tumorigenic role of G9a in breast cancer is still far from clear. In addition, growing evidence revealed that the disruption of iron homeostasis may contribute to the development of breast cancer (BC). Pathways of iron acquisition, efflux, storage and regulation are all perturbed in BC, suggesting that reprogramming of iron metabolism is a central aspect of tumor cells survival. Hephaestin (HEPH) is a ceruloplasmin homologue that converts iron (II) to iron (III), and mediates iron efflux in concert with ferroportin to transport iron across the basolateral membrane. It retains unclear whether HEPH concentration has any impact on the iron status of breast tissue, and breast cancer growth. In this study, we demonstrate that G9a exerts its oncogenic function by destruction cellular iron homeostasis. We revealed that G9a knockdown, and G9a specific inhibitors significantly up-regulated HEPH expression, decreased intracellular labile iron content, and then suppressed BC cells proliferation both in vitro and in vivo. This idea is further validated by the finding that the enhanced iron content and decreased HEPH expression are required for the increased proliferation of G9a-overexpressed breast cancer cells. Further, our CHIP and co-IP data demonstrate a traditional role of G9a as a transcriptional repressor that co-existed with YY1 and HDAC1, contribute to the reduction of HEPH transcription. In addition, depletion of HEPH with an increase in labile iron reversed cells growth in G9a silencing BC cells. These observations prompted us to investigate the relevance of G9a-HEPH pathway to human disease. The immunohistochemistry analysis of 75 breast cancer specimens revealed inverse staining patterns between G9a and HEPH expression in breast cancer tissues independent of BC type (Spearman's nonparametric correlation test, correlation coefficient: -0.678, p&amp;lt;0.05). Patients who owned a G9ahigh tumor had an even worse prognosis in this retrospective analysis, with a median overall survival of 56.9 months compared to 103.4 months in the G9alow tumors. And we revealed for the first time that low level of HEPH also correlated with overall lower disease-free survival. Finally, expression of high G9a and low HEPH correlated a worse prognosis. In summary, we propose that G9a has an upstream regulatory role in HEPH-mediated cellular iron hemostasis, leads to iron accumulation and stimulates breast cancer progression through its epigenetic silencing machinery. Our observations raise exciting possibilities regarding G9a and HEPH might be potential prognostic markers of breast cancer progression and targets for therapeutic intervention. Citation Format: Ya-fang Wang, Jie Zhang, Yi Su, Yan-yan Shen, Mei-yu Geng, Jian Ding, Yi Chen. H3K9 methyltransferase G9a epigenetically regulates breast cancer cell iron homeostasis via repressing ferroxidase hephaestin expression, promotes breast cancer growth [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 4680. doi:10.1158/1538-7445.AM2017-4680

MiR-27a-mediated antiproliferative effects of metformin on the breast cancer cell line MCF-7.

Metformin was demonstrated to have effects on breast cancer, and microRNA-27a (miR-27a) is a prognostic marker for breast cancer progression and patient survival. AMPKα2 was found to be a suppressor in breast cancer MCF-7 cells. Therefore, the present study aimed to explain this phenomenon in regards to the relationship between microRNAs (miRNAs) and their target genes and to predict how AMPKα2 may be a downstream target gene of miR-27a, thus exploring the new mechanism of metformin in the treatment of breast cancer regarding miRNAs. The MTT assay was used to assess whether metformin can inhibit the growth of breast cancer MCF-7 cells. The levels of miR-27a and AMPKα2 mRNA were examined using RT-PCR, and the expression levels of AMPKα2 and caspase-3 were determined by western blot analyses after MCF-7 cells were treated with metformin. The association of miR-27a and AMPKα2 was confirmed by transfecting cells with miR-27a mimics, miR-27a inhibitors and its negative control (NC), respectively. A luciferase assay was conducted to detect the miR-27a binding to the AMPKα2 3'-untranslated region (3'-UTR). The results of the MTT assay showed that metformin suppressed the growth of MCF-7 cells in a dose-and time‑dependent manner. miR-27a was downregulated, and AMPKa2 was upregulated after intervention with metformin, and caspase-3 was activated. Transfection tests showed that the expression of AMPKα2 was downregulated in the MCF-7 cells after transfection of the miR-27a mimics. The luciferase assay verified the binding of miR-27a to the AMPKα2 3'-UTR. In conclusion, metformin inhibited MCF-7 cell growth, and miR-27a plays a vital role in this process by targeting AMPKα2.

TIP60 inhibits metastasis by ablating DNMT1-SNAIL2-driven epithelial-mesenchymal transition program.

HIV-Tat-interacting protein of 60 kDa (TIP60) is a lysine acetyltransferase and known to be downregulated in multiple cancers. Among various signalling pathways, TIP60 is implicated in regulating epithelial-mesenchymal transition (EMT). Here, we show that TIP60 expression abrogates cell migration and metastatic potential of breast cancer cells using in vitro and in vivo models. Mechanistically, we show that this is through its ability to destabilize DNMT1 and inhibit SNAIL2 function (SNAIL2-mediated EMT/cell migration). Depletion of TIP60 stabilizes DNMT1 and increases SNAIL2 levels, resulting in EMT. Recruitment of DNMT1 to the SNAIL2 targets in the absence of TIP60 increases DNA methylation on their promoter region and further represses the expression of epithelial markers. In pathophysiological scenario, we find TIP60 to be significantly downregulated in breast cancer patients with poor overall survival and disease-free survival prognoses. These data suggest that levels of TIP60 can be a prognostic marker of breast cancer progression and stabilization of TIP60 could be a promising strategy to treat cancers.

Osteopontin splice variants are differential predictors of breast cancer treatment responses.

BackgroundOsteopontin is a marker for breast cancer progression, which in previous studies has also been associated with resistance to certain anti-cancer therapies. It is not known which splice variants may mediate treatment resistance.MethodsHere we analyze the association of osteopontin variant expression before treatment, differentiated according to immunohistochemistry with antibodies to exon 4 and to the osteopontin-c splice junction respectively, with the ensuing therapy responses in 119 Polish breast cancer patients who presented between 1995 and 2008.ResultsWe found from Cox hazard models, logrank test and Wilcoxon test that osteopontin exon 4 was associated with a favorable response to tamoxifen, but a poor response to chemotherapy with CMF (cyclophosphamide, methotrexate, fluorouracil). Osteopontin-c is prognostic, but falls short of being a significant predictor for sensitivity to treatment.ConclusionsThe addition of osteopontin splice variant immunohistochemistry to standard pathology work-ups has the potential to aid decision making in breast cancer treatment.

TIP60-miR-22 axis as a prognostic marker of breast cancer progression.

MicroRNAs (miRNAs) are 22- to 24-nucleotide, small, non-coding RNAs that bind to the 3'UTR of target genes to control gene expression. Consequently, their dysregulation contributes to many diseases, including diabetes and cancer. miR-22 is up-regulated in numerous metastatic cancers and recent studies have suggested a role for miR-22 in promoting stemness and metastasis. TIP60 is a lysine acetyl-transferase reported to be down-regulated in cancer but the molecular mechanism of this reduction is still unclear. In this study, we identify TIP60 as a target of miR-22. We show a negative correlation in the expression of TIP60 and miR-22 in breast cancer patients, and show that low levels of TIP60 and high levels of miR-22 are associated with poor overall survival. Furthermore, pathway analysis using high miR-22/low TIP60 and low miR-22/high TIP60 breast cancer patient datasets suggests association of TIP60/miR-22 with epithelial-mesenchymal transition (EMT), a key alteration in progression of cancer cells. We show that blocking endogenous miR-22 can restore TIP60 levels, which in turn decreases the migration and invasion capacity of metastatic breast cancer cell line. These results provide mechanistic insight into TIP60 regulation and evidence for the utility of the combination of TIP60 and miR-22 as prognostic indicator of breast cancer progression.

Fatty acid and phospholipid biosynthetic pathways are regulated throughout mammary epithelial cell differentiation and correlate to breast cancer survival

This work combined gene and protein expression, gas chromatography-flame ionization detector, and hydrophilic interaction liquid chromatography-tandem mass spectrometry to compare lipid metabolism changes in undifferentiated/proliferating vs. functionally differentiated mammary epithelial cells (MECs) and to study their correlation to breast cancer survival. Sixty-eight genes involved in lipid metabolism were changed in MEC differentiation. Differentiated cells showed induction of Elovl6 (2-fold), Scd1 (4-fold), and Fads2 (2-fold), which correlated with increased levels of C16:1 n-7 and C18:1 n-9 (1.5-fold), C20:3 n-6 (2.5-fold), and C20:4 n-6 (6-fold) fatty acids (FAs) and more phospholipids (PLs) containing these species. Further, increased expression (2- to 3-fold) of genes in phosphatidylethanolamine (PE) de novo biosynthesis resulted in a 20% PE increase. Proliferating/undifferentiated cells showed higher C16:0 (1.7-fold) and C18:2 n-6 (4.2-fold) levels and more PLs containing C16:0 FAs [PC(16:0/16:1), PG(16:0/18:2), PG(16:0/18:1), and SM(16:0/18:0)]. Kaplan-Meier analysis of data from 3455 patients with breast cancer disclosed a positive correlation for 59% of genes expressed in differentiated MECs with better survival. PE biosynthesis and FA oxidation correlated with better prognosis in patients with breast cancer, including the basal-like subtype. Therefore, genes involved in mammary gland FA and PL metabolism and their resulting molecular species reflect the cellular proliferative ability and differentiation state and deserve further studies as potential markers of breast cancer progression

Expression and clinical significance of matrix metalloproteinase-9 in lymphatic invasiveness and metastasis of breast cancer.

BackgroundMatrix metalloproteinase 9 (MMP-9) is a type-IV collagenase that is highly expressed in breast cancer, but its exact role in tumor progression and metastasis is unclear.Methods MMP-9 mRNA and protein expression was examined by real-time reverse transcriptase PCR and immunohistochemical staining, respectively, in 41 breast cancer specimens with matched peritumoral benign breast epithelial tissue and suspicious metastatic axillary lymph nodes. Lymph vessels were labeled with D2-40 and lymphatic microvessel density (LMVD) was calculated. Correlation of MMP-9 protein expression with clinicopathological parameters and LMVD was also evaluated.ResultsMMP-9+ staining in breast cancer specimens (35/41, 85.4%) was higher than in matched epithelium (21/41, 51.2%; P<0.05) and lymph nodes (13/41, 31.7%; P<0.001). Higher MMP-9 mRNA expression was also detected in tumor specimens compared with matched epithelial tissues and lymph nodes (P<0.05). Elevated MMP-9 expression was correlated with lymph node metastasis and LMVD (P<0.05).ConclusionMMP-9 was overexpressed in breast cancer specimens compared with peritumoral benign breast epithelium and lymph nodes. Moreover, its expression in the matched epithelium and lymph nodes was positively associated with lymph node metastasis, and its expression in lymph nodes was positively associated with lymphangiogenesis in breast cancer. Thus, MMP-9 is a potential marker for breast cancer progression.

Beta haemoglobin (hbb) is a novel marker of breast cancer progression

Searchable abstracts of presentations at key conferences on calcified tissues ISSN 2052-1219 (online)

HIF-2α as a prognostic marker for breast cancer progression and patient survival

Malignant cells show increased invasion potency in vitro and in vivo. This process is considered to be mediated by matrix-metalloproteases (MMPs). Hypoxia-inducible factor-2α (HIF-2α) may upregulate MMP-2 expression; however, little is known about the correlation between HIF-2α and MMP-2 expressions in breast cancer. The current study investigated this correlation immunohistochemically according to various clinical and pathological features in 102 paraffin-embedded archival tissue block specimens from patients with breast cancer. HIF-2α and MMP-2 expression was detected in 60.8% (62/102) and 65.7% (67/102) of tumor samples, respectively. HIF-2α expression was significantly correlated with tumor size (P = 0.019), lymph node involvement (P = 0.035), and metastasis (P = 0.035). MMP-2 expression was significantly associated with lymph node involvement (P = 0.043) and metastasis (P = 0.003). Univariate analyses revealed that HIF-2α (P = 0.001) and MMP-2 (P = 0.000) expressions were significantly associated with a poorer survival rate, as well as tumor size, lymph node invasion, and distant metastasis. Multivariate analysis revealed that HIF-2α (P = 0.003) and the T-stage (P = 0.000) were independent prognostic factors of overall survival. Spearman correlation analysis revealed that HIF-2α and MMP-2 expressions were significantly correlated (r = 0.990; P = 0.041). These results suggest that high HIF- 2α expression is associated with poor overall survival in patients with breast cancer, indicating that HIF-2α could be a valuable marker of breast cancer progression.

Abstract P1-04-06: Insertional mutagenesis identifies HACE1 as a HER2/Neu Cooperating Breast Cancer Tumor Suppressor Gene

Abstract The development of human breast cancer is a multi-step process leading from normal epithelium to fully transformed breast cancer. Early genetic changes result in hyperplasias which evolves into ductal carcinoma in situ (DCIS) and culminates as invasive ductal carcinoma. The transition from DCIS to invasive disease has been implicated as the key transition in breast cancer progression. Specific genomic, transcriptomic, and proteomic alterations responsible for this transition process have yet to been elucidated. HER2/Neu, a member of the EGFR family of receptor tyrosine kinases, is associated with poor clinical outcome. HER2/Neu overexpression/amplification is commonly seen (50–60%) in non-invasive lesions but is significantly less common (20–30%) in invasive and metastatic breast carcinoma. This indicates that HER2/Neu gives normal epithelium a proliferative advantage but additional genetic alterations are required for full malignant transformation. This idea is supported by the fact that transgenic mice that overexpress HER2/Neu develop spontaneous mammary tumors but only after a prolonged latency period. Recent forward genetic approaches use insertional mutagenesis to randomly integrate a strong promoter into the genome, activating downstream gene transcription that can lead to either gain or loss-of-function mutations based on the integration site. We used this insertional mutagenesis approach to induce anchorage-independent growth of isolated murine HER2/Neu over-expressing mammary epithelial cells. We identified HECT domain and ankyrin repeat containing E3 ubiquitin protein ligase 1 (HACE1) as a putative breast tumor suppressor protein whose loss leads to the formation of anchorage-independent colonies. Loss of HACE1 expression is commonly seen in breast cancer patients [as well as other tumor types] supporting the role of HACE1 as a breast tumor suppressor gene. Knockdown of HACE1 in human mammary epithelial cells (HMECs) results in the acquisition of anchorage-independent growth. Moreover, knockdown of HACE1 in established breast cancer cell lines that express moderate levels of HACE1 results in enhanced cloniginicity. Therefore, we propose that the loss of HACE1 can potentially be used as a predictive marker for breast cancer progression. Additional studies investigating the mechanism of HACE1 action may also identify therapeutic targets that counteract HACE1 loss. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-04-06.

MiR-27 as a Prognostic Marker for Breast Cancer Progression and Patient Survival

BackgroundMicroRNA-27a (miR-27a) is thought to be an onco-microRNA that promotes tumor growth and metastasis by downregulating ZBTB10. The potential predictive value of miR-27a was studied in breast cancer patients.MethodsThe expression of miR-27a and ZBTB10 was examined in 102 breast cancer cases using in situ hybridization (ISH) and immunohistochemistry techniques and were evaluated semi-quantitatively by examining the staining index. The Correlation of miR-27a and ZBTB10 expression was analyed by Spearman Rank Correlation. The association of miR-27a and ZBTB10 expression with clinicopathological characteristics was analyzed using the χ2 test, and their effects on patient survival were analyzed by a log-rank test and the Kaplan-Meier method. Univariate and multivariate Cox regression analyses were used to evaluate the prognostic values of miR-27a and ZBTB10.ResultsmiR-27a was markedly up-regulated in invasive breast cancers that expressed low levels of ZBTB10 (P<0.001). A reverse correlation between miR-27a and ZBTB10 was also observed in breast cancer tissue samples (rs = −0.478, P<0.001). Furthermore, the expression of miR-27a and ZBTB10 was significantly correlated with clinicopathological parameters, including tumor size, lymph node metastasis and distant metastasis (P<0.05), but not with receptor status. Patients with high miR-27a or low ZBTB10 expression tended to have significantly shorter disease-free survival times (57 months and 53 months, respectively, P <0.001) and overall survival times (58 months and 55 months, respectively, P <0.001). Univariate and multivariate analysis showed that both miR-27a and ZBTB10 were independent prognostic factors of disease-free survival in breast cancer patients (P <0.001), while only miR-27a was an independent predictor of overall survival (P <0.001).ConclusionsHigh miR-27a expression is associated with poor overall survival in patients with breast cancer, which suggests that miR-27a could be a valuable marker of breast cancer progression.

Arginase Activity in Patients with Breast Cancer: An Analysis of Plasma, Tumors, and Its Relationship with the Presence of the Estrogen Receptor

Background: Breast cancer is an important cause of cancerrelated death in women. In this pathological condition, arginase plays a role by providing ornithine as a substrate for the biosynthesis of polyamines which are important in tumor progression. The aim of this work was to determine the arginase activity in the plasma and tumors of patients with breast cancer; also, we investigated the relationship between this activity and the presence of the estrogen receptor. Patients and Methods: We evaluated the plasma arginase activity levels in 80 women with breast cancer and 42 healthy control subjects. We also measured the arginase levels in 42 breast cancer biopsies and 42 control tissues. Results: The mean activity of arginase in plasma was higher in breast cancer patients (0.78 nM/min/mg protein ± 0.04; p = 0.001) than in healthy volunteers (0.53 nM/ min/mg protein ± 0.04); however, this difference was indicative of patients in the advanced stages of the disease (n = 38, stage III; p < 0.0001). In addition, we did not find a relationship between the estrogen receptor and arginase activity. Conclusion: Our results show a higher arginase activity in the plasma of patients in the advanced stages of the disease, suggesting that arginase activity could serve as a possible biological marker of breast cancer progression.

Abstract 4593: Expression of Ecdysoneless in breast cancer progression predicts poor outcome in breast cancer patients

Abstract Breast cancer is the most common type of cancer and second leading cause of cancer-related deaths in women in the United States. Our laboratory has identified the protein hEcd (human ortholog of Drosophila Ecdysoneless) as a novel regulator of cell cycle. Previous studies showed that Ecd regulates cell cycle by regulating the Rb-E2F pathway. Given the dysregulation of the cell cycle machinery in cancer, we examined expression of Ecd in normal, benign, ductal carcinoma in situ (DCIS) and infiltrating ductal carcinoma (IDCs) of breast. In first cohort, we showed while normal and hyperplasia of breast barely showed Ecd expression, high Ecd expression was observed in DCIS and IDC patient tissue specimens. In this cohort of 104 IDC patents, Ecd expression was positively associated with higher grade (p=0.04).We then analyzed Ecd expression in a second larger cohort (954) and observed similar results, where increased Ecd expression was associated with tumors of higher histological grade (p=0.013), mitotic count (p=0.032), and Nottingham Prognostic Index score (p=0.014). Notably, Ecd expression was positively associated with HER2/neu (p=0.002) overexpression. Significantly, a positive association between Ecd expression and shorter breast cancer specific survival (BCSS) (p=0.008) and disease-free survival (DFS) (p=0.003) was observed in HER2/neu overexpressing patients. Taken together, our results demonstrate Ecd expression as a novel marker for breast cancer progression that predicts tumor progression and the clinical outcome in breast cancer patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4593. doi:1538-7445.AM2012-4593

Overexpression of a novel cell cycle regulator ecdysoneless in breast cancer: a marker of poor prognosis in HER2/neu-overexpressing breast cancer patients

Uncontrolled proliferation is one of the hallmarks of breast cancer. We have previously identified the human Ecd protein (human ortholog of Drosophila Ecdysoneless, hereafter called Ecd) as a novel promoter of mammalian cell cycle progression, a function related to its ability to remove the repressive effects of Rb-family tumor suppressors on E2F transcription factors. Given the frequent dysregulation of cell cycle regulatory components in human cancer, we used immunohistochemistry of paraffin-embedded tissues to examine Ecd expression in normal breast tissue versus tissues representing increasing breast cancer progression. Initial studies of a smaller cohort without outcomes information showed that Ecd expression was barely detectable in normal breast tissue and in hyperplasia of breast, but high levels of Ecd were detected in benign breast hyperplasia, ductal carcinoma in situ (DCIS) and infiltrating ductal carcinoma (IDCs) of the breast. In this cohort of 104 IDC patients, Ecd expression levels showed a positive correlation with higher grade (P = 0.04). Further analyses of Ecd expression using a larger, independent cohort (954) confirmed these results, with a strong positive correlation of elevated Ecd expression with higher histological grade (P = 0.013), mitotic index (P = 0.032), and Nottingham Prognostic Index score (P = 0.014). Ecd expression was positively associated with HER2/neu (P = 0.002) overexpression, a known marker of poor prognosis in breast cancer. Significantly, increased Ecd expression showed a strong positive association with shorter breast cancer specific survival (BCSS) (P = 0.008) and disease-free survival (DFS) (P = 0.003) in HER2/neu overexpressing patients. Taken together, our results reveal Ecd as a novel marker for breast cancer progression and show that levels of Ecd expression predict poorer survival in Her2/neu overexpressing breast cancer patients.Electronic supplementary materialThe online version of this article (doi:10.1007/s10549-011-1946-8) contains supplementary material, which is available to authorized users.

Metastasis: Genetics, Mechanism, and Diagnostic and Therapeutic Strategies

Metastasis: Genetics, Mechanism, and Diagnostic and Therapeutic Strategies