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Background: Breast cancer is the second most common cause of cancer mortality worldwide. Biomarker discovery has led to advances in understanding molecular phenotyping and thus has a great potential for precision management of this diverse disease. Despite increased interest in the biomarker field, only a small number of breast cancer biomarkers are known to be clinically useful. Therefore, it is very important to characterise the success rate of biomarkers in this field and study potential reasons for the deficit. We therefore aim to achieve quantitative characterisation of the biomarker translation gap by tracking the progress of prognostic biomarkers associated with breast cancer recurrence. Methods: An electronic systematic search was conducted in Medline and Embase databases using keywords and mesh headings associated with breast cancer recurrence biomarkers (1940–2023). Abstracts were screened, and primary clinical studies involving breast cancer recurrence biomarkers were selected. Upon identification of relevant literature, we extracted the biomarker name, date of publication and journal name. All analyses were performed using IBM SPSS Statistics and GraphPad prism (La Jolla, California, USA). Results: A total of 19,195 articles were identified, from which 4597 articles reported breast cancer biomarkers associated with recurrence. Upon data extraction, 2437 individual biomarkers were identified. Out of these, 23 are currently recommended for clinical use, which corresponds to only 0.94% of all discovered biomarkers. Conclusions: This study characterised for the first time the translational gap in the field of recurrence-related breast cancer biomarkers, indicating that only 0.94% of identified biomarkers were recommended for clinical use. This denotes an evident barrier in the biomarker research field and emphasises the need for a clearer route from biomarker discovery through to implementation. [ABSTRACT FROM AUTHOR]

Background This phase II, open-label, multicentre study aimed to evaluate changes in cell proliferation and biomarkers, as well as efficacy of lapatinib in treatment-naïve patients with HER-2-negative primary breast cancer. Patients and methods Patients received 1500 mg lapatinib for 28–42 days before surgery with repeat biopsies and measurements. The primary end point was inhibition of cell proliferation measured by Ki67; the secondary end points included clinical response, adverse events and changes in FOXO3a, FOXM1, p-AKT and HER-3. Results Overall, there was no significant reduction in Ki67 with treatment (assessment carried out in 28 of 31 subjects enrolled). However, four patients (14%) showed a reduction in Ki67 ≥50%. Four of 25 patients (16%) had a partial response to treatment judged by sequential ultrasound measurements. Response, in terms of either Ki67 or ultrasound, did not relate to changes in any biomarker assessed at baseline, including the estrogen receptor (ER) and epidermal growth factor receptor (EGFR). However, all four clinical responders were HER-3 positive, as were three of four Ki67 responders. Conclusions Overall, a pre-surgical course of lapatinib monotherapy had little effect on this group of patients; however, in subsets of patients, especially those with HER-3-positive tumors, we observed either reduction in proliferation (Ki67) or tumor size; EGFR/ER status had no impact. [ABSTRACT FROM PUBLISHER]

The article presents a medical research study that compares the survival of patients and the safety of the use of the drugs exemestane and tamoxifen in post-menopausal women with estrogen-receptor-positive early breast cancer or estrogen-receptor-unknown breast cancer after they received 2-3 years of treatment with tamoxifen. Exemestane is a third-generation aromatase inhibitor. The researchers found that improvements in disease-free survival in patients treated with exemestane after 2-3 years of tamoxifen treatment lasted after treatment. A modest improvement in overall survival in patients who received exemestane instead of the continued use of tamoxifen was seen.

Background: The estrogen receptor-a (ERa) is implicated in the initiation and progression of breast cancer. Endocrine therapeutics, including tamoxifen (OHT) and fulvestrant (ICI182780; ICI) improve disease-free survival. Despite positive effects, de novo or acquired resistance to endocrine therapies frequently occurs. It has recently been published that nuclear receptor-interacting protein 1, NRIP1, also called RIP140, encodes an ER corepressor RIP140 and has a role in the regulation of breast cancer cell growth in response to anti-estrogens. FOXA1 has previously been shown to function as a 'pioneer factor' and dictate ER dependent gene expression in both normal and malignant breast epithelial cells. In this study we investigated the expression of ERa cofactors RIP140 and FOXA1 and their roles in hormonal therapy and endocrine resistance. Methods: Tamoxifen sensitive or resistant breast cancer cell lines were analysed for protein and mRNA expression by western blotting and quantitative real-time PCR with or without the inhibition of ERa with tamoxifen or ICI. To determine the functional role of RIP140 and FOXA1 as well as their interaction in breast cancer, tamoxifen sensitive breast cancer cells (eg. MCF-7 and ZR-75-1) were transfected with either RIP140 or FOXA1 expression vector and examined for the expression of ER-target genes by Western blot and RT-qPCR analysis. The consequence of depletion of RIP140 and FOXA1 by RNA interference (RNAi) was also studied in these breast cancer cells. The expression of RIP140 and FOXA1 and potential target genes were also validated in breast cancer patient samples by Immunohistochemistry. Results: We first examined the basal expression levels of RIP140 and FOXA1 in tamoxifen sensitive as well as resistant breast cancer cell lines. The expression levels of RIP140 were low in the resistance cells compared with their parental sensitive counterparts, while that of FOXA1 had no significant difference between the cell lines. The degradation of ERa by ICI treatment resulted in the down-regulation of RIP140 and FOXA1 expression in the endocrine sensitive. Our experiments also demonstrated the functional interaction between RIP140 and FOXA1 and showed that depletion of RIP140 by RNA interference (RNAi) in sensitive cells resulted in reduction of FOXA1 expression. We also indentified from this work, a number of ER-regulated genes which are activated by FOXA1 and repressed by RIP140 expression. The regulation of these target genes by ERa, FOXA1 and RIP140 were also confirmed in the breast cancer patient samples. Conclusion: The results from this study demonstrated that RIP140 and FOXA1 play a pivotal role in dictating hormonal sensitivity and resistance in breast cancer. Moreover, this work also identified a number of ERa-regulated genes which are downstream targets of FOXA1 and RIP140, and as such, they may be reliable prognostic markers for endocrine sensitivity in breast cancer. [ABSTRACT FROM AUTHOR]

Presents the results of a study on the disease-free survival of postmenopausal women with primary breast cancer who switched to the aromatase inhibitor exemestane after tamoxifen therapy. Characteristics of the aromatase inhibitor; Number of first events that occurred in the study, including metastatic recurrence; Hazard ratio of reduced incidence of contralateral breast cancer in the exemestane group.

The article presents an obituary for David Vigushin, senior lecturer in cancer medicine, Imperial College, London, England.

By means of an immunocytochemical method the 1.25-dihydroxyvitamin D [1.25(OH)2D] receptor status of tumours from 136 patients with primary carcinoma of the breast was determined. Patients with receptor-positive tumours had significantly longer disease-free survival than those with receptor-negative tumours (Chi2 = 4.01, p less than 0.05). 1.25(OH)2D3 inhibits the proliferation of several established human breast cancer cell lines in vitro. Effects of 1.25(OH)2D3 on breast tumour growth in vitro were assessed by means of the nitrosomethylurea-induced rat mammary tumour model of hormone-responsive breast cancer. Treatment of tumour-bearing animals with 0.1 microgram of the synthetic analogue, 1 alpha-hydroxyvitamin D3, three times weekly produced significant inhibition of tumour progression. Taken together, these studies suggest that the levels of 1.25(OH)2D occurring in vivo may exert an inhibitory effect on receptor-positive tumours. Further studies are required to evaluate the role of vitamin D metabolites in the treatment of human malignant disease. [ABSTRACT FROM AUTHOR]

Background: Effective anticancer therapy is thought to involve induction of tumour cell death through apoptosis and/or necrosis. [18F]ICMT-11, an isatin sulfonamide caspase-3/7-specific radiotracer, has been developed for PET imaging and shown to have favourable dosimetry, safety, and biodistribution. We report the translation of [18F]ICMT-11 PET to measure chemotherapy-induced caspase-3/7 activation in breast and lung cancer patients receiving first-line therapy.Results: Breast tumour SUVmax of [18F]ICMT-11 was low at baseline and unchanged following therapy. Measurement of M30/M60 cytokeratin-18 cleavage products showed that therapy was predominantly not apoptosis in nature. While increases in caspase-3 staining on breast histology were seen, post-treatment caspase-3 positivity values were only approximately 1%; this low level of caspase-3 could have limited sensitive detection by [18F]ICMT-11-PET. Fourteen out of 15 breast cancer patients responded to first-line chemotherapy (complete or partial response); one patient had stable disease. Four patients showed increases in regions of high tumour [18F]ICMT-11 intensity on voxel-wise analysis of tumour data (classed as PADS); response was not exclusive to patients with this phenotype. In patients with lung cancer, multi-parametric [18F]ICMT-11 PET and MRI (diffusion-weighted- and dynamic contrast enhanced-MRI) showed that PET changes were concordant with cell death in the absence of significant perfusion changes.Conclusion: This study highlights the potential use of [18F]ICMT-11 PET as a promising candidate for non-invasive imaging of caspase3/7 activation, and the difficulties encountered in assessing early-treatment responses. We summarize that tumour response could occur in the absence of predominant chemotherapy-induced caspase-3/7 activation measured non-invasively across entire tumour lesions in patients with breast and lung cancer. [ABSTRACT FROM AUTHOR]

Background: Micrometastases in bone marrow of women with early breast cancer were first identified immunocytochemically in the 1980s. We report on the original cohort of women with a median follow-up of 30 years.Patients and Methods: In total, 350 women with primary breast cancer had eight bone marrow aspirates examined with antibody to epithelial membrane antigen. Data on long-term mortality were obtained via record linkage to death certification.Results: At a 30-year median follow-up, 79 out of 89 (89%) patients with micrometastases have died compared with 202 out of 261 (77%) without (hazard ratio=1.46 (95% CI 1.12-1.90), P=0.0043). Most marked effect of micrometastases on overall survival (OS) was seen in patients aged ⩽ 50 at surgery (N=97, P=0.012), and on all patients within 10 years of diagnosis. In multivariable analyses, the presence of micrometastases was no longer a statistically significant prognostic factor.Conclusions: Bone marrow micrometastases are predictive for OS, particularly in the first decade and in younger patients. [ABSTRACT FROM AUTHOR]

Background: The optimal ways of using aromatase inhibitors or tamoxifen as endocrine treatment for early breast cancer remains uncertain.Methods: We undertook meta-analyses of individual data on 31,920 postmenopausal women with oestrogen-receptor-positive early breast cancer in the randomised trials of 5 years of aromatase inhibitor versus 5 years of tamoxifen; of 5 years of aromatase inhibitor versus 2-3 years of tamoxifen then aromatase inhibitor to year 5; and of 2-3 years of tamoxifen then aromatase inhibitor to year 5 versus 5 years of tamoxifen. Primary outcomes were any recurrence of breast cancer, breast cancer mortality, death without recurrence, and all-cause mortality. Intention-to-treat log-rank analyses, stratified by age, nodal status, and trial, yielded aromatase inhibitor versus tamoxifen first-event rate ratios (RRs).Findings: In the comparison of 5 years of aromatase inhibitor versus 5 years of tamoxifen, recurrence RRs favoured aromatase inhibitors significantly during years 0-1 (RR 0·64, 95% CI 0·52-0·78) and 2-4 (RR 0·80, 0·68-0·93), and non-significantly thereafter. 10-year breast cancer mortality was lower with aromatase inhibitors than tamoxifen (12·1% vs 14·2%; RR 0·85, 0·75-0·96; 2p=0·009). In the comparison of 5 years of aromatase inhibitor versus 2-3 years of tamoxifen then aromatase inhibitor to year 5, recurrence RRs favoured aromatase inhibitors significantly during years 0-1 (RR 0·74, 0·62-0·89) but not while both groups received aromatase inhibitors during years 2-4, or thereafter; overall in these trials, there were fewer recurrences with 5 years of aromatase inhibitors than with tamoxifen then aromatase inhibitors (RR 0·90, 0·81-0·99; 2p=0·045), though the breast cancer mortality reduction was not significant (RR 0·89, 0·78-1·03; 2p=0·11). In the comparison of 2-3 years of tamoxifen then aromatase inhibitor to year 5 versus 5 years of tamoxifen, recurrence RRs favoured aromatase inhibitors significantly during years 2-4 (RR 0·56, 0·46-0·67) but not subsequently, and 10-year breast cancer mortality was lower with switching to aromatase inhibitors than with remaining on tamoxifen (8·7% vs 10·1%; 2p=0·015). Aggregating all three types of comparison, recurrence RRs favoured aromatase inhibitors during periods when treatments differed (RR 0·70, 0·64-0·77), but not significantly thereafter (RR 0·93, 0·86-1·01; 2p=0·08). Breast cancer mortality was reduced both while treatments differed (RR 0·79, 0·67-0·92), and subsequently (RR 0·89, 0·81-0·99), and for all periods combined (RR 0·86, 0·80-0·94; 2p=0·0005). All-cause mortality was also reduced (RR 0·88, 0·82-0·94; 2p=0·0003). RRs differed little by age, body-mass index, stage, grade, progesterone receptor status, or HER2 status. There were fewer endometrial cancers with aromatase inhibitors than tamoxifen (10-year incidence 0·4% vs 1·2%; RR 0·33, 0·21-0·51) but more bone fractures (5-year risk 8·2% vs 5·5%; RR 1·42, 1·28-1·57); non-breast-cancer mortality was similar.Interpretation: Aromatase inhibitors reduce recurrence rates by about 30% (proportionately) compared with tamoxifen while treatments differ, but not thereafter. 5 years of an aromatase inhibitor reduces 10-year breast cancer mortality rates by about 15% compared with 5 years of tamoxifen, hence by about 40% (proportionately) compared with no endocrine treatment.Funding: Cancer Research UK, Medical Research Council. [ABSTRACT FROM AUTHOR]

Background: Intergroup Exemestane Study (IES) was a randomised study that showed a survival benefit of switching adjuvant endocrine therapy after 2-3 years from tamoxifen to exemestane. PathIES aimed to assess the potential prognostic and predictive value of ERβ1 and ERβ2 expression in primary tumours in order to determine benefit in the two treatment arms. Patients and methods: Primary tumour samples were available for 1256 patients (27% IES population). ERβ1 and ERβ2 expression was dichotomised at the median IHC score (high if ERβ1 ≥ 191, ERβ2 ≥ 164). Hazard ratios (HRs) were estimated by multivariable Cox proportional hazards models adjusting for clinicopathological factors. Treatment effects with biomarker expressions were determined by interaction tests. Analysis explored effects of markers both as a continuous variable and with dichotomised cut-offs. Results: Neither ERβ1 nor ERβ2 were associated with disease-free survival (DFS) or overall survival (OS) in the whole cohort. In patients treated with continued tamoxifen, high ERβ1 expression compared with low was associated with better DFS [HR = 0.38:95% confidence interval (CI) 0.21-0.68, P = 0.001]. DFS benefit of exemestane over tamoxifen (HR = 0.40:95% CI 0.22-0.70) was found in the low ERβ1 subgroup (interaction P = 0.01). No significant difference with treatment was observed for ERβ2 expression in either DFS or OS. Conclusion: In the PathIES population, exemestane appeared to be superior to tamoxifen among patients with low ERβ1 expression but not in those with high ERβ1 expression. This is the first trial of its kind to report a parameter potentially predicting benefit of an aromatase inhibitor when compared with tamoxifen and an independent validation is warranted. [ABSTRACT FROM AUTHOR]

The forkhead box transcription factor FOXM1 is an essential effector of G2/M-phase transition, mitosis and the DNA damage response. As such, it is frequently deregulated during tumorigenesis. Here we report that FOXM1 is dynamically modified by SUMO1 but not by SUMO2/3 at multiple sites. We show that FOXM1 SUMOylation is enhanced in MCF-7 breast cancer cells in response to treatment with epirubicin and mitotic inhibitors. Mutation of five consensus conjugation motifs yielded a SUMOylation-deficient mutant FOXM1. Conversely, fusion of the E2 ligase Ubc9 to FOXM1 generated an auto-SUMOylating mutant (FOXM1-Ubc9). Analysis of wild-type FOXM1 and mutants revealed that SUMOylation inhibits FOXM1 activity, promotes translocation to the cytoplasm and enhances APC/Cdh1-mediated ubiquitination and degradation. Further, expression of the SUMOylation-deficient mutant enhanced cell proliferation compared with wild-type FOXM1, whereas the FOXM1-Ubc9 fusion protein resulted in persistent cyclin B1 expression and slowed the time from mitotic entry to exit. In summary, our findings suggest that SUMOylation attenuates FOXM1 activity and causes mitotic delay in cytotoxic drug response. [ABSTRACT FROM AUTHOR]

FOXM1 is implicated in genotoxic drug resistance but its mechanism of action remains elusive. We show here that FOXM1-depletion can sensitize breast cancer cells and mouse embryonic fibroblasts (MEFs) into entering epirubicin-induced senescence, with the loss of long-term cell proliferation ability, the accumulation of γH2AX foci, and the induction of senescence-associated β-galactosidase activity and cell morphology. Conversely, reconstitution of FOXM1 in FOXM1-deficient MEFs alleviates the accumulation of senescence-associated γH2AX foci. We also demonstrate that FOXM1 regulates NBS1 at the transcriptional level through an forkhead response element on its promoter. Like FOXM1, NBS1 is overexpressed in the epirubicin-resistant MCF-7EpiR cells and its expression level is low but inducible by epirubicin in MCF-7 cells. Consistently, overexpression of FOXM1 augmented and FOXM1 depletion reduced NBS1 expression and epirubicin-induced ataxia-telangiectasia mutated (ATM)phosphorylation in breast cancer cells. Together these findings suggest that FOXM1 increases NBS1 expression and ATM phosphorylation, possibly through increasing the levels of the MRN(MRE11/RAD50/NBS1) complex. Consistent with this idea, the loss of P-ATM induction by epirubicin in the NBS1-deficient NBS1-LBI fibroblasts can be rescued by NBS1 reconstitution. Resembling FOXM1, NBS1 depletion also rendered MCF-7 and MCF-7EpiR cells more sensitive to epirubicin-induced cellular senescence. In agreement, the DNA repair-defective and senescence phenotypes in FOXM1-deficent cells can be effectively rescued by overexpression of NBS1. Moreover, overexpression of NBS1 and FOXM1 similarly enhanced and their depletion downregulated homologous recombination (HR) DNA repair activity. Crucially, overexpression of FOXM1 failed to augment HR activity in the background of NBS1 depletion, demonstrating that NBS1 is indispensable for the HR function of FOXM1. The physiological relevance of the regulation of NBS1 expression by FOXM1 is further underscored by the strong and significant correlation between nuclear FOXM1 and total NBS1 expression in breast cancer patient samples, further suggesting that NBS1 as a key FOXM1 target gene involved in DNA damage response, genotoxic drug resistance and DNA damage-induced senescence. [ABSTRACT FROM AUTHOR]

Background Aromatase inhibitors ( AIs) are central to the management of oestrogen receptor-positive breast cancer in the adjuvant and metastatic setting. Levels of circulating steroid hormones ( SHs) were measured in patients established on AIs to investigate: the influence of body mass index ( BMI) in both the adjuvant and metastatic setting; the class of AI utilized in the adjuvant setting (steroidal versus non-steroidal); and differences in SH levels between women treated adjuvantly and those receiving a second-line AI for locally advanced/metastatic disease. Methods Plasma levels of androstenedione, 5-androstene-3β,17β-diol, dehydroepiandrosterone, oestradiol and testosterone were measured by radioimmunoassay in women with breast cancer who were receiving AIs in either an adjuvant or a metastatic setting. Differences between mean SH levels by class of AI, BMI, and second-line versus adjuvant therapy were assessed. Results Sixty-four women were receiving AI therapy, 45 (70 per cent) in an adjuvant setting and 19 (30 per cent) were taking a second-line AI. There was no significant correlation between BMI and SH levels. However, BMI was significantly higher in the second-line AI cohort compared with the adjuvant cohort (29·8 versus 26·2 kg/m2 respectively; P = 0·026). In the adjuvant setting, patients receiving a steroidal AI had significantly higher levels of all five hormones ( P < 0·050). In the second-line AI cohort, oestradiol levels were significantly higher than in the adjuvant cohort (4·5 versus 3·3 pg/ml respectively; P = 0·022). Multivariable analysis adjusted for BMI confirmed the higher residual oestradiol level in the second-line AI group ( P = 0·063) and a significantly higher androstenedione level ( P = 0·022). Conclusion Residual levels of SH were not significantly influenced by BMI. However, the significant differences in residual SH levels between the second-line and adjuvant AI cohort is of relevance in the context of resistance to AI therapy, and warrants further investigation. [ABSTRACT FROM AUTHOR]

Resistance to chemotherapeutic treatment, which is indirectly responsible for many cancer deaths, is normally associated with an aggressive phenotype including increased cell motility and acquisition of invasive properties. Here we describe how breast cancer cells overcome doxorubicin-induced senescence and become drug resistant by overexpression of the microRNA (miR)-106b∼25 cluster. Although all three miRs in the cluster contribute to the generation of doxorubicin resistance, miR-25 is the major contributor to this phenotype. All three miRs in this cluster target EP300, a transcriptional activator of E-cadherin, resulting in cells acquiring a phenotype characteristic of cells undergoing epithelial-to-mesenchymal transition (EMT), including an increase in both cell motility and invasion, as well as the ability to proliferate after treatment with doxorubicin. These findings provide a novel drug resistance/EMT regulatory pathway controlled by the miR-106b∼25 cluster by targeting a transcriptional activator of E-cadherin. [ABSTRACT FROM AUTHOR]

Background:Cyclin-dependent kinases (CDKs) control cell cycle progression, RNA transcription and apoptosis, making them attractive targets for anticancer drug development. Unfortunately, CDK inhibitors developed to date have demonstrated variable efficacy.Methods:We generated drug-resistant cells by continuous low-dose exposure to a model pyrazolo[1,5-a]pyrimidine CDK inhibitor and investigated potential structural alterations for optimal efficacy.Results:We identified induction of the ATP-binding cassette (ABC) transporters, ABCB1 and ABCG2, in resistant cells. Assessment of features involved in the ABC transporter substrate specificity from a compound library revealed high polar surface area (>100 Å2) as a key determinant of transporter interaction. We developed ICEC-0782 that preferentially inhibited CDK2, CDK7 and CDK9 in the nanomolar range. The compound inhibited phosphorylation of CDK substrates and downregulated the short-lived proteins, Mcl-1 and cyclin D1. ICEC-0782 induced G2/M arrest and apoptosis. The permeability and cytotoxicity of ICEC-0782 were unaffected by ABC transporter expression. Following daily oral dosing, the compound inhibited growth of human colon HCT-116 and human breast MCF7 tumour xenografts in vivo by 84% and 94%, respectively.Conclusion:We identified a promising pyrazolo[1,5-a]pyrimidine compound devoid of ABC transporter interaction, highly suitable for further preclinical and clinical evaluation for the treatment of cancer. [ABSTRACT FROM AUTHOR]

Resistance to endocrine therapy in breast cancer is common. With the aim of discovering new molecular targets for breast cancer therapy, we have recently identified LMTK3 as a regulator of the estrogen receptor-alpha (ERα) and wished to understand its role in endocrine resistance. We find that inhibition of LMTK3 in a xenograft tamoxifen (Tam)-resistant (BT474) breast cancer mouse model results in re-sensitization to Tam as demonstrated by a reduction in tumor volume. A whole genome microarray analysis, using a BT474 cell line, reveals genes significantly modulated (positively or negatively) after LMTK3 silencing, including some that are known to be implicated in Tam resistance, notably c-MYC, HSPB8 and SIAH2. We show that LMTK3 is able to increase the levels of HSPB8 at a transcriptional and translational level thereby protecting MCF7 cells from Tam-induced cell death, by reducing autophagy. Finally, high LMTK3 levels at baseline in tumors are predictive for endocrine resistance; therapy does not lead to alteration in levels, whereas in patient's plasma samples, acquired LMTK3 gene amplification (copy number variation) was associated with relapse while receiving Tam. In aggregate, these data support a role for LMTK3 in both innate (intrinsic) and acquired (adaptive) endocrine resistance in breast cancer. [ABSTRACT FROM AUTHOR]

Background:Current approaches for detecting circulating tumour cells (CTCs) in blood are dependent on CTC enrichment and are based either on surface epithelial markers on CTCs or on cell size differences. The objectives of this study were to develop and characterise an ultrasensitive multiplex fluorescent RNA in situ hybridisation (ISH)-based CTC detection system called CTCscope. This method detects a multitude of tumour-specific markers at single-cell level in blood.Methods:Healthy blood samples spiked with tumour cell lines were used as a model system for the development and initial characterisation of CTCscope. To demonstrate the feasibility of CTC detection in patient blood, duplicate blood samples were drawn from 45 metastatic breast cancer patients for analysis by CTCscope and the CellSearch system. The association of CTCs with the tumour marker CA15-3 and progression-free survival (PFS) were assessed.Results:CTCscope detected CTC transcripts of eight epithelial markers and three epithelial-mesenchymal-transition (EMT) markers for increased sensitivity. CTCscope was used to detect CTCs with minimal enrichment, and did not detect apoptotic or dead cells. In patient blood samples, CTCs detected by CellSearch, but not CTCscope, were positively correlated with CA15-3 levels. Circulating tumour cells detected by either CTCscope or CellSearch predicted PFS (CTCscope, HR (hazard ratio) 2.26, 95% CI 1.18-4.35, P=0.014; CellSearch, HR 2.50, 95% CI 1.27-4.90, P=0.008).Conclusion:CTCscope offers unique advantages over existing CTC detection approaches. By enumerating and characterising only viable CTCs, CTCscope provides additional prognostic and predictive information in therapy monitoring. [ABSTRACT FROM AUTHOR]

Purpose: Breast cancer is associated with adverse outcomes in patients with the metabolic syndrome phenotype. To study this further, we examined the relationship between serum metabolite levels and the components of metabolic syndrome with treatment outcomes in breast cancer. Methods: A total of 88 women with measurable breast cancer were studied; their serum metabolites as assessed by 1H nuclear magnetic resonance spectroscopy, blood pressure, lipids, glucose, body mass index and waist circumference were recorded and correlated with treatment response. Results: We identified metabolic syndrome in approximately half of our cohort (42 patients) and observed a significant trend (P = 0.03) of increased incidence of metabolic syndrome in partial response (33.3%), stable disease (42.9%) and progressive disease groups (66.1%). High blood sugar predicted a poor response (P < 0.001). Logistic regression of metabonomic data demonstrated that high lactate (P = 0.03) and low alanine (P = 0.01) combined with high glucose (P = 0.01) were associated with disease progression. Conclusions: Metabolic syndrome is commonly observed in metastatic breast cancer and these patients have poorer outcomes. These data, which support our previous findings, suggest that high blood glucose as part of metabolic syndrome is associated with a poor response in breast cancer. They also validate new therapeutic approaches that focus on metabolism. [ABSTRACT FROM PUBLISHER]

Background:The Intergroup Exemestane Study (IES) (ISRCTN11883920) demonstrated improved survival for postmenopausal women with ER-positive/unknown primary breast cancer who switched to exemestane after 2-3 years tamoxifen, compared with those continuing on tamoxifen to complete 5 years therapy. This was achieved without detriment to on-treatment quality-of-life (QoL). We report on- and post-treatment QoL impact in IES.Methods:A total of 582 patients from 8 countries participated in the QoL substudy. Functional Assessment of Cancer Therapy-Breast (FACT-B) and endocrine symptom subscale (ES) were completed at baseline, 3, 6, 9, 12, 18, 24, 30, 36, 48 and 60 months. The primary endpoint was FACT-B Trial Outcome Index (TOI); secondary endpoints included severity of individual endocrine symptoms.Results:Both the groups showed gradual improvement in overall QoL and lessening of total endocrine symptoms post treatment compared with baseline (P<0.002). There was no evidence of any between-group differences in TOI. Vasomotor complaints remained high on treatment. Vaginal discharge was more frequent (P<0.01) with tamoxifen up to 24 months from baseline. In both the groups, post-treatment libido did not recover to baseline levels.Conclusion:Clinical benefits of switching to exemestane are accompanied by good overall QoL. Although some symptoms persist, the majority of endocrine symptoms improve after treatment completion. [ABSTRACT FROM AUTHOR]

Background:The aim of this study was to gain insight into breast cancer dormancy by examining different measures of minimal residual disease (MRD) over time in relation to known prognostic factors.Methods:Sixty-four primary breast cancer patients on follow-up (a median of 8.3 years post surgery) who were disease free had sequential bone marrow aspirates and blood samples taken for the measurement of disseminated tumour cells (DTCs), circulating tumour cells (CTCs) by CellSearch and qPCR measurement of overlapping (96-bp and 291-bp) amplicons in circulating free DNA (cfDNA).Results:The presence of CTCs was correlated with the presence of DTCs measured by immunocytochemistry (P=0.01) but both were infrequently detected. Increasing cfDNA concentration correlated with ER, HER2 and triple-negative tumours and high tumour grade, and the 291-bp amplicon was inversely correlated with DTCs measured by CK19 qRT-PCR (P=0.047).Conclusion:Our results show that breast cancer patients have evidence of MRD for many years after diagnosis despite there being no overt evidence of disease. The inverse relationship between bone marrow CK19 mRNA and the 291-bp amplicon in cfDNA suggests that an inverse relationship between a measure of cell viability in the bone marrow (DTCs) and cell death in the plasma occurs during the dormancy phase of breast cancer. [ABSTRACT FROM AUTHOR]

Background: Human epidermal growth factor receptor 2 (HER2) is amplified and overexpressed in 20-25% of breast cancers. This study investigated circulating free DNA (cfDNA) for detection of HER2 gene amplification in patients with breast cancer.Methods: Circulating free DNA was extracted from plasma of unselected patients with primary breast cancer (22 before surgery and 68 following treatment), 30 metastatic patients and 98 female controls using the QIAamp Blood DNA Mini Kit (Qiagen). The ratio of HER2 to an unamplified reference gene (contactin-associated protein 1 (CNTNAP1)) was measured in cfDNA samples by quantitative PCR (qPCR) using SK-BR-3 cell line DNA as a positive control.Results: We validated the qPCR assay with DNA extracted from 23 HER2 3+ and 40 HER2-negative tumour tissue samples; the results agreed for 60 of 63 (95.2%) tumours. Amplification was detected in cfDNA for 8 of 68 patients following primary breast cancer treatment and 5 of 30 metastatic patients, but was undetected in 22 patients with primary breast cancer and 98 healthy female controls. Of the patients with amplification in cfDNA, 10 had HER2 3+ tumour status by immunohistochemistry.Conclusions: The results demonstrate for the first time the existence of amplified HER2 in cfDNA in the follow-up of breast cancer patients who are otherwise disease free. This approach could potentially provide a marker in patients with HER2-positive breast cancer. [ABSTRACT FROM AUTHOR]

In this study, we investigated the regulation of FOXM1 expression by estrogen receptor α (ERα) and its role in hormonal therapy and endocrine resistance. FOXM1 protein and mRNA expression was regulated by ER-ligands, including estrogen, tamoxifen (OHT) and fulvestrant (ICI182780; ICI) in breast carcinoma cell lines. Depletion of ERα by RNA interference (RNAi) in MCF-7 cells downregulated FOXM1 expression. Reporter gene assays showed that ERα activates FOXM1 transcription through an estrogen-response element (ERE) located within the proximal promoter region. The direct binding of ERα to the FOXM1 promoter was confirmed in vitro by mobility shift and DNA pull-down assays and in vivo by chromatin immunoprecipitation (ChIP) analysis. Our data also revealed that upon OHT treatment ERα recruits histone deacetylases to the ERE site of the FOXM1 promoter, which is associated with a decrease in histone acetylation and transcription activity. Importantly, silencing of FOXM1 by RNAi abolished estrogen-induced MCF-7 cell proliferation and overcame acquired tamoxifen resistance. Conversely, ectopic expression of FOXM1 abrogated the cell cycle arrest mediated by the anti-estrogen OHT. OHT repressed FOXM1 expression in endocrine sensitive but not resistant breast carcinoma cell lines. Furthermore, qRT–PCR analysis of breast cancer patient samples revealed that there was a strong and significant positive correlation between ERα and FOXM1 mRNA expression. Collectively, these results show FOXM1 to be a key mediator of the mitogenic functions of ERα and estrogen in breast cancer cells, and also suggest that the deregulation of FOXM1 may contribute to anti-estrogen insensitivity. [ABSTRACT FROM AUTHOR]

Background: The antiestrogen tamoxifen may have partial estrogen-like effects on the postmenopausal uterus. Aromatase inhibitors (AIs) are increasingly used after initial tamoxifen in the adjuvant treatment of postmenopausal early breast cancer due to their mechanism of action: a potential benefit being a reduction of uterine abnormalities caused by tamoxifen. [ABSTRACT FROM PUBLISHER]

The DEAD-box RNA helicases p68 (DDX5) and p72 (DDX17) have been shown to act as transcriptional co-activators for a diverse range of transcription factors, including oestrogen receptor-α (ERα). Here, we show that, although both proteins interact with and co-activate ERα in reporter gene assays, small interfering RNA-mediated knockdown of p72, but not p68, results in a significant inhibition of oestrogen-dependent transcription of endogenous ERα-responsive genes and oestrogen-dependent growth of MCF-7 and ZR75-1 breast cancer cells. Furthermore, immunohistochemical staining of ERα-positive primary breast cancers for p68 and p72 indicate that p72 expression is associated with an increased period of relapse-free and overall survival (P=0.006 and 0.016, respectively), as well as being inversely associated with Her2 expression (P=0.008). Conversely, p68 shows no association with relapse-free period, or overall survival, but it is associated with an increased expression of Her2 (P=0.001), AIB-1 (P<0.001) and higher tumour grade (P=0.044). Our data thus highlight a crucial role for p72 in ERα co-activation and oestrogen-dependent cell growth and provide evidence in support of distinct but important roles for both p68 and p72 in regulating ERα activity in breast cancer. [ABSTRACT FROM AUTHOR]

Gamma-secretase activity is vital for the transmembrane cleavage of Notch receptors and the subsequent migration of their intracellular domains to the nucleus. Notch overexpression has been associated with breast, colon, cervical and prostate cancers. We tested the effect of three different gamma-secretase inhibitors (GSIs) in breast cancer cells. One inhibitor (GSI1) was lethal to breast cancer cell lines at concentrations of 2 muM and above but had a minimal effect on the non-malignant breast lines. GSI1 was also cytotoxic for a wide variety of cancer cell lines in the NCI60 cell screen. GSI1 treatment resulted in a marked decrease in gamma-secretase activity and downregulation of the Notch signalling pathway with no effects on expression of the gamma-secretase components or ligands. Flow cytometric and western blot analyses indicated that GSI1 induces a G2/M arrest leading to apoptosis, through downregulation of Bcl-2, Bax and Bcl-XL. GSI1 also inhibited proteasome activity. Thus, the gamma-secretase inhibitor GSI1 has a complex mode of action to inhibit breast cancer cell survival and may represent a novel therapy in breast cancer. [ABSTRACT FROM AUTHOR]

In addition to the direct targeting effects on HER2-positive cells, trastuzumab may have a therapeutic role modulating the activity of the cellular immune system in patients with breast cancer. To investigate this further, the balance of T-regulatory (T(reg)), Th17, natural killer (NK) and NK T (NKT) cells before, during and after trastuzumab therapy was investigated. Sequential frequencies of circulating T(reg) cells, Th17 cells, NK and NKT cells were measured in peripheral blood of breast cancer patients and normal controls throughout therapy. Individuals with breast cancer had significantly higher T(reg) frequencies of peripheral blood compared with healthy controls (9.2 or 8.6 vs 6%; P<0.05), and no significant differences in T(reg) frequencies were observed between HER2-positive and HER2-negative individuals. The number of Th17 cells was lowest in HER2-positive patients compared with both healthy controls and HER2-negative patients (0.31 vs 0.75% or 0.84%; P=0.01). There appeared to be an inverse relationship between T(reg) and Th17 frequencies in metastatic breast cancer (MBC) with T(reg) levels significantly reduced during treatment with trastuzumab (P=0.04), whereas Th17 frequencies were concomitantly increased (P=0.04). This study supports earlier data that T(reg) cells are present at higher frequencies in breast cancer patients compared with healthy individuals. For the first time, we show that HER2-positive individuals with breast carcinomas have reduced numbers of circulating Th17 cells, which appear, in turn to have an inverse relationship with T(reg) frequency in MBC. The change in balance of the T(reg) : Th17 ratio appears to characterise the cancer state, and furthermore, is disrupted by trastuzumab therapy. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether primary breast cancer patients showed evidence of circulating tumour cells (CTCs) during follow-up as an alternative to monitoring disseminated bone marrow tumour cells (DTCs) by immunocytochemistry and reverse transcriptase (RT)–PCR for the detection of micrometastases. We planned to compare CTC and DTC frequency in low-risk and high-risk patients. We identified two cohorts of primary breast cancer patients who were at low (group II, T1N0, n=18) or high (group III, >3 nodes positive (with one exception, a patient with two positive nodes) n=33) risk of relapse who were being followed up after primary treatment. We tested each cohort for CTCs using the CellSearch system on 1–7 occasions and for DTCs by immunocytochemistry and RT–PCR on 1–2 occasions over a period of 2 years. We also examined patients with confirmed metastatic disease (group IV, n=12) and 21 control healthy volunteers for CTCs (group I). All group I samples were negative for CTCs. In contrast, 7 out of 18 (39%) group II primary patients and 23 out of 33 (70%) group III patients were positive for CTCs (P=0.042). If we count only samples with >1 cell as positive: 2 out of 18 (11%) group II patients were positive compared with 10 out of 33 (30%) in group III (P=0.174). In the case of DTCs, 1 out of 13 (8%) group II patients were positive compared with 19 out of 27 (70%) in group III (P<0.001). Only 10 out of 33 (30%) patients in group III showed no evidence of CTCs in all tests over the period of testing, compared with 11 out of 18 (61%) in group II (P=0.033). A significant proportion of poor prognosis primary breast cancer patients (group III) have evidence of CTCs on follow-up. Many also have evidence of DTCs, which are more often found in patients who were lymph node positive. As repeat sampling of peripheral blood is more acceptable to patients, the measurement of CTCs warrants further investigation because it enables blood samples to be taken more frequently, thus possibly enabling clinicians to have prior warning of impending overt metastatic disease.British Journal of Cancer (2009) 100, 160–166. doi:10.1038/sj.bjc.6604773 www.bjcancer.com Published online 25 November 2008 [ABSTRACT FROM AUTHOR]

Estrogen receptora(ERa) is a ligand-inducible transcription factor that acts to regulate gene expression by binding to palindromic DNA sequence, known as the estrogen response element, in promoters of estrogen-regulated genes. In breast cancer ERaplays a central role, where estrogen-regulated gene expression leads to tumor initiation, growth and survival. As an approach to silencing estrogen-regulated genes, we have studied the activities of a fusion protein between ERaand the promyelocytic leukemia zinc-finger (PLZF) protein, a transcriptional repressor that acts through chromatin remodeling. To do this, we have developed lines from the estrogen-responsive MCF-7 breast cancer cell line in which the expression of the fusion protein PLZF-ERais conditionally regulated by tetracycline and shows that these feature long-term silencing of the expression of several well-characterized estrogen-regulated genes, namely pS2, cathepsin-D and the progesterone receptor. However, the estrogen-regulated growth of these cells is not inhibited unless PLZF-ERaexpression is induced, an observation that we have confirmed both in vitro and in vivo. Taken together, these results show that PLZF-ERais a potent repressor of estrogen-regulated gene expression and could be useful in distinguishing estrogen-regulated genes required for the growth of breast cancer cells.Gene Therapy (2005) 12, 452-460. doi:10.1038/sj.gt.3302421 Published online 13 January 2005 [ABSTRACT FROM AUTHOR]

TNF is a proinflammatory cytokine involved in the pathogenesis of chronic inflammatory diseases, but also in metastasis in certain types of cancer. In terms of therapy, TNF is targeted by anti-TNF neutralising monoclonal antibodies or soluble TNF receptors. Recently, a novel strategy based on the generation of self anti-TNF antibodies (TNF autovaccination) has been developed. We have previously shown that TNF autovaccination successfully generates high anti-TNF antibody titres, blocks TNF and ameliorates collagen-induced arthritis in DBA/1 mice. In this study, we examined the ability of TNF autovaccination to generate anti-TNF antibody titres and block metastasis in the murine B16F10 melanoma model. We found that immunisation of C57BL/6 mice with TNF autovaccine produces a 100-fold antibody response to TNF compared to immunisation with phosphate-buffered saline vehicle control and significantly reduces both the number (P<0.01) and size of metastases (P<0.01) of B16F10 melanoma cells. This effect is also observed when an anti-TNF neutralising monoclonal antibody is administered, confirming the essential role TNF plays in metastasis in this model. This study suggests that TNF autovaccination is a cheaper and highly efficient alternative that can block TNF and reduce metastasis in vivo and trials with TNF autovaccination are already underway in patients with metastatic cancer.British Journal of Cancer (2004) 90, doi:10.1038/sj.bjc.6601670 www.bjcancer.com Published online 24 February 2004 [ABSTRACT FROM AUTHOR]

Currently, the therapy for breast cancer is determined by immunohistochemical staining of the primary tumour for oestrogen receptor alpha (ERa). However, a proportion of ERa-positive patients fail to respond to tamoxifen and a proportion of ERa-negative patients show response. Here, we describe a novel procedure for the purification of malignant breast epithelial cells in an attempt to identify these patients at an early stage. Using this procedure, we are able to purify malignant cells to >90% purity as determined by immunohistochemical staining, cytology and fluorescent in situ hybridisation (FISH). While the malignant cells can be maintained in culture they do not proliferate in contrast to purified breast epithelial cells from reduction mammoplasties. Moreover, ERa and progesterone receptor (PR) expression is maintained in malignant cells, whereas normal epithelial cells rapidly lose Era and PR. Functional studies were performed on the separated malignant cells in terms of their response to oestradiol and tamoxifen. Four out of the seven ERa-positive tumours showed a significant reduction in cell numbers after tamoxifen treatment compared to oestradiol, ERa negative tumours failed to show a response. We conclude that (a) it is possible to purify and maintain breast cancer cells for a sufficient period to permit functional studies and (b) ERa is retained in culture facilitating the use of these cells in studies of the mechanism of endocrine response and resistance in vitro.British Journal of Cancer (2003) 88, 1071-1076. doi:10.1038/sj.bjc.6600866 www.bjcancer.com [ABSTRACT FROM AUTHOR]

Fibroblast growth factor 8 can transform NIH3T3 cells and its expression has been found to be associated with breast and prostate cancer. Following our finding that fibroblast growth factor 8 mRNA expression is increased in breast cancer, we have undertaken an immunohistochemistry study of fibroblast growth factor 8 expression in a series of human breast tissues and other normal tissues. Our findings confirm increased expression of fibroblast growth factor 8 in malignant breast tissue but also show significant fibroblast growth factor 8 expression in non-malignant breast epithelial cells. No significant difference in fibroblast growth factor 8 expression was found between different grades of ductal carcinoma, lobular carcinoma and ductal carcinoma in-situ or cancer of different oestrogen receptor, progesterone receptor or nodal status. The highest levels of fibroblast growth factor 8 expression were found in lactating breast tissues and fibroblast growth factor 8 was also detected in human milk. A survey of other normal tissues showed that fibroblast growth factor 8 is expressed in the proliferative cells of the dermis and epithelial cells in colon, ovary fallopian tube and uterus. Fibroblast growth factor 8 appears to be expressed in several organs in man and appears to have an importance in lactation. [ABSTRACT FROM AUTHOR]

The extracellular matrix components laminin and type IV collagen have both been localized in the basement membrane of the normal human breast ductule. Breaks in the continuity of these components occur in breast carcinomas and have been implicated in tumor metastasis. Using a postembedding ultrastructural immunogold technique, laminin and type IV collagen were distributed within the basal lamina surrounding the normal human breast ductule. Both components were present diffusely along the basal lamina and were not localized to particular regions, and neither were present between epithelial and myoepithelial cells. Laminin binding of these cells thus probably occurs only at the basal aspect where they are in contact with the basal lamina and is not involved in the cell-cell adhesion between epithelial and myoepithelial cells. This study provides a basis for further ultrastructural investigations of extracellular matrix components in normal and neoplastic breast tissue. [ABSTRACT FROM AUTHOR]

Fibroblast growth factor 8 (FGF8) is an important developmental protein which is oncogenic and able to co-operate with wnt-1 to produce mouse mammary carcinoma. The level of expression of FGF8 mRNA was measured in 68 breast cancers and 24 non-malignant breast tissues. Elevated levels of FGF8 mRNA were found in malignant compared to non-malignant breast tissues with significantly more malignant tissues expressing FGF8 (P=0.019) at significantly higher levels (P=0.031). In situ hybridization of breast cancer tissues and analysis of purified populations of normal epithelial cells and breast cancer cell lines showed that malignant epithelial cells expressed FGF8 mRNA at high levels compared to non-malignant epithelial and myoepithelial cells and fibroblasts. Although two of the receptors which FGF8 binds to (FGFR2-IIIc, FGFR3-IIIc) are not expressed in breast cancer cells, an autocrine activation loop is possible since expression of fibroblast growth factor receptor (FGFR) 4 and FGFR1 are retained in malignant epithelial cells. This is the first member of the FGF family to have increased expression in breast cancer and a potential autocrine role in its progression. [ABSTRACT FROM AUTHOR]

Background: Bone-marrow micrometastases have been found in patients with primary breast cancer. We report long-term follow-up of women with primary breast cancer, diagnosed between 1981 and 1986, who had multiple aspirates taken at the time of initial surgery.Methods: 350 women with primary breast cancer were examined immunocytochemically with antibody to epithelial membrane antigen. We investigated associations with various prognostic factors as well as the effect of micrometastases on relapse-free survival and overall survival.Findings: At median follow-up of 12.5 years, 151 patients had metastatic disease and 136 patients had died from breast cancer. 10-year relapse-free and overall survival were 43.9% (95% CI 33.4-54.7) and 44.9% (34.2-55.9) in patients with micrometastases, and 62.7% (56.5-68.6) and 65.7% (59.4-71.5) in patients without micrometastases at presentation (p<0.001). For relapse-free survival and overall survival, allowing for tumour size, lymph-node status, and vascular invasion, the effect of micrometastases decreased and was no longer significant, with a hazard ratio of 1.09 (0.74-1.61) for relapse-free survival and 1.21 (0.84-1.75) for overall survival.Interpretation: The presence of bone-marrow micrometastases in patients with primary breast cancer is associated with a shorter relapse-free survival and overall survival, but is not an independent prognostic factor. This immunocytochemical technique may be of value in patients for whom pathological tumour size and lymph-node status are unavailable (ie, patients receiving primary medical treatment). [ABSTRACT FROM AUTHOR]

One hundred and sixteen patients with locally advanced or metastatic breast cancer were randomized to receive CMF (cyclophosphamide 600 mg m(-2) day 1 and 8 i.v., 5-fluorouracil 600 mg m(-2) day 1 and 8 i.v., methotrexate 40 mg m(-2) day 1 and 8 i.v., monthly for 6 cycles) or MM (methotrexate 30 mg m(-2), mitoxantrone 6.5 mg m(-2), both i.v. day 1 3-weekly for 8 cycles) as first line treatment with chemotherapy. Objective responses occurred in 17 patients out of 58 (29%) who received CMF and nine out of 58 (15%) who received MM; 95% confidence interval for difference in response rates (-1%-29%), P = 0.07. No statistically significant differences were seen in overall survival or time to progression between the two regimes although a tendency towards a shorter progression time on the MM regime must be acknowledged. There was, however, significantly reduced haematological toxicity (P < 0.001) and alopecia (P < 0.001) and fewer dose reductions and delays in patients randomized to MM. No statistically significant differences were seen between the two regimes in terms of quality of life (QOL). However, some association between QOL and toxicity was apparent overall with pooled QOL estimates tending to indicate a worsening in psychological state with increasing maximum toxicity over treatment. Despite the fact that results surrounding response rates and time to progression did not reach statistical significance, their possible compatibility with an improved outcome on CMF treatment must be borne in mind. However, MM is a well-tolerated regimen with fewer side-effects than CMF, which with careful patient management and follow-up, therefore, may merit consideration as a first-line treatment to palliate patients with metastatic breast cancer who are infirm or elderly. [ABSTRACT FROM AUTHOR]

Endothelial cells are a promising target for cancer gene therapy because neoangiogenesis is vital for the supply of oxygen and nutrients to solid tumours. However, endothelial cells have been reported to be difficult to transfect. We demonstrate high rates of transfection with the reporter gene pSV40βgal using DC-Chol/DOPE cationic liposomes and lower rates with the novel polyamine cationic lipo- somes ACHx/DC-Chol/DOPE and ACO/DC-Chol/DOPE. Endothelial cells transfected with HSV-thymidine kinase using DC-Chol/DOPE demonstrated 3 log10 increased cytotoxicity compared with controls when exposed to the prodrug ganciclovir, thereby demonstrating significant biological effect. [ABSTRACT FROM AUTHOR]

Background: The Activating Transcription Factor 2 (ATF2) gene is a member of the ATF and CREB group of bZIP transcription factors. It is involved in in transcriptional control, chromatin remodelling and the DNA damage response. Two threonine residues (Thr69 and Thr71) within the activation domain (AD) are important for its transcriptional activation and high pThr69/pThr71-ATF2 has been correlated with a well-differentiated phenotype in breast cancer (BC). In this study the protein expression of ATF2 & pThr71-ATF2 (pATF2) and its association with clinico-pathological features and outcome in a well defined BC series were studied. Methods: The expression of ATF2 and pATF2 was assessed in the Nottingham Tenovus Primary Breast Cancer Series which consists of 1650 cases of primary invasive BC. ATF2 and pATF2 were correlated with clinico-pathological data as well as outcome in those high risk cases (NPI>3.4) based on exposure to tamoxifen. Results: A total of 1351 tumours were suitable for analysis of both ATF2 and pATF2; 436/1351 (32%) of BC co-expressed ATF2 and pATF2 while 414/1351(31%) were negative for both ATF2 and pThr71-ATF2. Co-expression ATF2 and pATF2 was highly significantly associated luminal breast cancer phenotype, well differentiation, low proliferation (low mitotic index, low Ki67 and low SPAG5; ps<0.0001), hormonal receptors, high expression of ER associated proteins (cyclin D1 and Bcl2; p < 0.0001), high expression of c-jun (p < 0.0001), JNK (p < 0.0001), pSRC3 (p < 0.0001), and active p53 transcriptional pathways that regulate cell cycle progression and apoptosis (p21+ve, MDM2+ve, MDM4+ve & Bax+ve; p < 0.0001) and absence of basal like phenotypes (p < 0.0001). While absence of ATF2 and pATF2 was significantly associated with loss of expression of the key DNA repair proteins including XRCC1 (p < 0.0001), BRCA1 (p < 0.0001), ATM (p = 0.008) and TOP2A (p < 0.0001) reflecting a higher risk of genomic instability. In addition, absence of pATF2 was associated with abnormal expression of other tumour suppressor proteins such as p53 (p = 0.03), p16 (p < 0.001) and FHIT (p < 0.0001) and was associated with epithelial- mesenchymal transition indicator proteins (vimentin+ve, p63+ve, CK18-ve, and E-cadherin- ve). There was no association with outcome based on the expression of ATF2 either with or without tamoxifen. However, expression of pATF2 was associated with significantly longer breast cancer specific survival (HR: 0.69, 95% CI: 0.51-0.92, p = 0.01) and disease free survival (HR: 0.66, 95% CI: 0.51-0.86, p = 0.002) in patients exposed to tamoxifen; this was not observed when tamoxifen was not used in high risk ER+ ve BC. Discussion: Coexpression of ATF2 and pATF2 is associated with a luminal phenotype and features of good prognostic disease. The absence of ATF2 and pATF2 was associated with a higher risk of genomic instability. While ATF2 had no prognostic significance, the presence of the transcriptionally active form was associated with a significant improvement in outcome in patients treated with tamoxifen, which was not observed in the absence of tamoxifen. The role of the transcriptionally active form of ATF2 warrants further investigation with regard to breast cancer and its role in modulating response to tamoxifen. [ABSTRACT FROM AUTHOR]

Introduction: Steroid receptor coactivator 3 (SRC3) acts as a coactivator of nuclear receptors including estrogen receptor-alpha (ER). SRC3 has been implicated in the pathogenesis of breast cancer (BC) as well as in resistance to endocrine therapy. SRC3 is phosphorylated at a number of residues following the stimulation of growth factors or hormones. Tyr24 and Ser543 are both phosphorylated upon estrogen stimulation, while Tyr24 is modulated by JNK and Ser543 by both p38 and JNK. To date, the importance and potential role of phosphorylation at these residues has not been explored in BC. In this study we assessed the protein expression of SRC3, pTyr24 and pSer543 and association with clinico-pathological features and outcome in a well defined breast cancer series. Methods: The expressions of SRC3, pTyr24 and pSer543 were assessed in the Nottingham Tenovus Primary Breast Cancer Series which consists of 1650 cases of primary invasive. SRC3, pTyr24 and pSer543 were correlated with clinico-pathological data as well as outcome. Results: SRC3 expression was significantly associated with unfavourable clinicopathological features including ER -ve (p = 0.02), PR -ve (p = .038), HER2 overexpression (p < 0.0001), Triple negative phenotype (p = 0.001), high proliferation (p < 0.0001), high histological grade (p < 0.001), and lympho-vascular invasion. On contrast, the expression of pSer543 was significantly associated with a luminal phenotype, well differentiation, low proliferation (low mitotic index, low Ki67 and low SPAG5; p < 0.0001), hormonal receptors (ERα+ve/PR+ve/AR+ve), absence of both ER-B1 and ER-B5 (p < 0.01), high expression of ER -α associated proteins (cyclin D1 and Bcl2; p < 0.0001), high expression of c-jun (p < 0.0001), JNK (p < 0.0001), SRC3 (p < 0.0001), T24 (p < 0.001) and active p53 transcriptional pathways that regulate cell cycle progression and apoptosis (MDM2+ve, MDM4+ve and Bax+ve; p < 0.01) and absence of basal like phenotypes (p < 0.01). The absence of pSer543 was significantly associated with loss of expression of the key DNA repair proteins including XRCC1 (p < 0.0001), BRCA1 (p < 0.0001), ATM (p = 0.008) and TOP2A (p < 0.0001) reflecting a higher risk of genomic instability. Moreover, absence of pSer543 was more common in BC with a triple negative phenotype (p < 0.001). With regard to outcome, no association with outcome based on the expression of SRC3 either with or without tamoxifen was observed. However, expression of pSer543 was associated with significantly longer disease free survival (DFS) (p < 0.00001) and breast cancer specific survival (BCSS) (p = 0.0001). Furthermore, absence of pSer543 was associated with both a shorter DFS (p = 0.007) and BCSS (p = 0.01) in ER+ ve high risk BC. pSer534 was confirmed as an independent prognostic factor after adjustment for endocrine therapy and other validated prognostic factors and absent of pSer534 was associated with a two-fold increased risk of recurrence (HR = 1.9, CI 95%= 1.2-3.1). Data on Tyr24 will also be presented. Conclusion: Phosphorylation at Ser543 is associated with a luminal phenotype, positive prognostic factors and sensitivity to tamoxifen. Furthermore, it is an independent prognostic factor. pS543 is a novel prognostic marker in BC and warrants further investigation. [ABSTRACT FROM AUTHOR]

Background: Our recent human kinome screening to identify new regulators of estrogen receptor a (ERa) suggested an important role of kinase suppressor of ras 1 (KSR1) in breast cancer. KSR1 was originally identified as a positive regulator interacting with both RAS and RAF in the mitogen-activated protein kinase (MAPK) pathway. Recent studies have suggested that KSR1 may have dual functions as a scaffolding protein and also a protein kinase. Although KSR1 has been implicated in Ras-dependent cancers, its clinical significance and function in breast cancer have not been elucidated. Methods: The clinical significance of KSR1 was assessed by analyzing its expression in 2 breast cancer tissue microarrays (TMAs, n=1000) by immunohistochemistry. Pearson chi and Fisher's Exact Test were used to correlate the expression levels with various tumor biomarkers; Kaplan Meier analyses were used to investigate impact on disease-free (DFS) and overall survival (OS). Multivariate Cox-proportional hazards analysis was also performed to evaluate the significant of KSR1 as an independent factor in breast cancer-specific survival (BCSS) and disease-free interval (DFI). The expression levels of KSR1 in breast cancer cell lines were measured by RT-qPCR and western blotting. A KSR1 stable over-expression breast cancer cell line (MCF7-KSR1) was generated to study its effect on growth and colony formation by 3D matrigel assay and soft agar assay in vitro. Furthermore, MCF7-KSR1 stable cells were also used in nude mice xenograft model in vivo. Luciferase reporter assay was employed to examine the effect of KSR1 on p53 transcriptional activity. Further immunofluorescence staining, western blotting and reporter assays were performed to elucidate the interaction between KSR1, BRCA1 and p53. Results: KSR1 was expressed with low (60%) and high levels (40%) in breast cancer patients. High expression correlated significantly with longer DFS (p = 0.014) and longer OS (p = 0.012) in more than 20 yrs follow-up. Interestingly, KSR1 was positively associated with BRCA1 (p = 0.002) and reversely with p53 (p = 0.038). High KSR1 levels were a significant predictor of longer breast cancer-specific survival BCSS (p = 0.001) and longer disease free interval DFI (p = 0.002) independent of tumour stage, grade and size. RT-qPCR and western blotting demonstrated that KSR1 is ubiquitously expressed in breast cancer cell lines. In vitro 3D matrigel and soft agar assay showed that MCF7-KSR1 cells had a significant decreased number of colonies and formed smaller size colonies compared to MCF7-vector cells. Furthermore, over-expression of KSR1 (MCF7-KSR1) significantly suppressed the growth of breast cancer xenografts in nude mice. Finally, KSR1 was involved in the functional interaction between BRCA1 and p53 and elevated KSR1 potentially resulted in up-regulated BRCA1. KSR1 also inhibited p53-dependent transcriptional activity through suppression of p53 acetylation and promotion of p53 neddylation. Conclusion: KSR1 is an independent prognostic factor in breast cancer and high KSR1 expression correlates with longer DFS and OS. Furthermore, it is potential that KSR1 is important in tumour suppression by its involvement in functional feedback regulation of BRCA1 and p53. [ABSTRACT FROM AUTHOR]

Summary:We describe a patient with moderately severe (British Thorax Society Step IV/V) asthma requiring regular inhaled and oral corticosteroids to control symptoms who experienced resolution of her asthma following high-dose chemotherapy and autologous stem cell transplantation for breast cancer. As far as the authors are aware this is the first reported case.Bone Marrow Transplantation (2003) 32, 847-848. doi:10.1038/sj.bmt.1704268 [ABSTRACT FROM AUTHOR]

Presents a correction to the article "Inhibiting estrogen responses in breast cancer cells using a fusion protein encoding estrogen receptor and the transcriptional repressor PLZF," that was previously published in the journal "Gene Therapy."

Presents a correction on the incorrect publication of authors of the article "Inhibiting estrogen responses in breast cancer cells using a fusion protein encoding estrogen receptor-and the transcriptional repressor PLZF," published in the 2005 issue of "Gene Therapy."