Breast cancer

Effect of comorbidity on urinary neopterin in patients with breast carcinoma

Urinary neopterin is increased in less than 20% of patients with breast carcinoma. Moderately increased neopterin concentrations are also known to accompany comorbid conditions commonly observed in patients with breast carcinoma, for example, diabetes mellitus or complications of atherosclerosis. In the present study, we evaluated the effect of the presence of comorbid conditions on urinary neopterin. A trend for higher neopterin concentrations was observed in patients with most of the comorbid conditions, but significantly higher neopterin was observed only in patients aged 70 years or older and in a heterogeneous group of patients with comorbidity other than diabetes mellitus, thyroid disorder, hyperlipidaemia, cardiac disorder or other malignancy. Significantly higher neopterin levels were noted in patients with two or more comorbid conditions. In conclusion, present data demonstrate an association between systemic immune activation reflected in increased urinary neopterin concentrations and age or presence of comorbid diseases in patients with breast carcinoma. A cumulative effect was observed with the presence of two or more comorbid conditions resulting in significantly increased urinary neopterin. These observations should be taken into account when interpreting the changes of parameters of systemic immune and inflammatory response in patients with breast carcinoma.

Association of common variants in mismatch repair genes and breast cancer susceptibility: a multigene study

Background

MMR is responsible for the repair of base-base mismatches and insertion/deletion loops. Besides this, MMR is also associated with an anti-recombination function, suppressing homologous recombination. Losses of heterozygosity and/or microsatellite instability have been detected in a large number of skin samples from breast cancer patients, suggesting a potential role of MMR in breast cancer susceptibility.

Methods

We carried out a hospital-based case-control study in a Caucasian Portuguese population (287 cases and 547 controls) to estimate the susceptibility to non-familial breast cancer associated with some polymorphisms in mismatch repair genes (MSH3, MSH4, MSH6, MLH1, MLH3, PMS1 and MUTYH).

Results

Using unconditional logistic regression we found that MLH3 (L844P, G>A) polymorphism GA (Leu/Pro) and AA (Pro/Pro) genotypes were associated with a decreased risk: OR = 0.65 (0.45-0.95) (p = 0.03) and OR = 0.62 (0.41-0.94) (p = 0.03), respectively.

Analysis of two-way SNP interaction effects on breast cancer revealed two potential associations to breast cancer susceptibility: MSH3 Ala1045Thr/MSH6 Gly39Glu - AA/TC [OR = 0.43 (0.21-0.83), p = 0.01] associated with a decreased risk; and MSH4 Ala97Thr/MLH3 Leu844Pro - AG/AA [OR = 2.35 (1.23-4.49), p = 0.01], GG/AA [OR = 2.11 (1.12-3,98), p = 0.02], and GG/AG [adjusted OR = 1.88 (1.12-3.15), p = 0.02] all associated with an increased risk for breast cancer.

Conclusion

It is possible that some of these common variants in MMR genes contribute significantly to breast cancer susceptibility. However, further studies with a large sample size will be needed to support our results.

Dysregulated expression of Fau and MELK is associated with poor prognosis in breast cancer

Introduction

Programmed cell death through apoptosis plays an essential role in the hormone-regulated physiological turnover of mammary tissue. Failure of this active gene-dependent process is central both to the development of breast cancer and to the appearance of the therapy-resistant cancer cells that produce clinical relapse. Functional expression cloning in two independent laboratories has identified Finkel–Biskis–Reilly murine sarcoma virus-associated ubiquitously expressed gene (Fau) as a novel apoptosis regulator and candidate tumour suppressor. Fau modifies apoptosis-controller Bcl-G, which is also a key target for candidate oncoprotein maternal embryonic leucine zipper kinase (MELK).

Methods

We have used RNA interference to downregulate Fau and Bcl-G expression, both simultaneously and independently, in breast cancer cells in vitro to determine the importance of their roles in apoptosis. Expression of Fau, Bcl-G and MELK was measured by quantitative RT-PCR in breast cancer tissue and in matched breast epithelial tissue from the same patients. Expression data of these genes obtained using microarrays from a separate group of patients were related to patient survival in Kaplan–Meier analyses.

Results

siRNA-mediated downregulation of either Fau or Bcl-G expression inhibited apoptosis, and the inhibition produced by combining the two siRNAs was consistent with control of Bcl-G by Fau. Fau expression is significantly reduced in breast cancer tissue and this reduction is associated with poor patient survival, as predicted for a candidate breast cancer tumour suppressor. In addition, MELK expression is increased in breast cancer tissue and this increase is also associated with poor patient survival, as predicted for a candidate oncogene. Bcl-G expression is reduced in breast cancer tissue but decreased Bcl-G expression showed no correlation with survival, indicating that the most important factors controlling Bcl-G activity are post-translational modification (by Fau and MELK) rather than the rate of transcription of Bcl-G itself.

Conclusions

The combination of in vitro functional studies with the analysis of gene expression in clinical breast cancer samples indicates that three functionally interconnected genes, Fau, Bcl-G and MELK, are crucially important in breast cancer and identifies them as attractive targets for improvements in breast cancer risk prediction, prognosis and therapy.

P53 codon 72 polymorphism contributes to breast cancer risk: a meta-analysis based on 39 case-control studies

P53 is a tumor suppressor gene and plays important roles in the etiology of breast cancer. Studies revealing conflicting results on the role of p53 codon 72 polymorphism (G>C) on breast cancer risk led us to perform a meta-analysis to investigate this relationship. Thirty-nine published studies, including 26,041 breast cancer cases and 29,679 controls were identified. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations. The overall results suggested that the variant genotypes were associated with a significantly reduced breast cancer risk (GC vs. GG: OR = 0.91, 95% CI: 0.83-1.00; CC/GC vs. GG: OR = 0.90, 95% CI: 0.82-0.99). In the stratified analyses, significantly decreased risks were also found among European populations (GC vs. GG: OR = 0.89, 95% CI: 0.80-0.99; CC/GC vs. GG: OR = 0.88, 95% CI: 0.80-0.98) and studies with population-based controls (GC vs. GG: OR = 0.88, 95% CI: 0.78-0.98; CC/GC vs. GG: OR = 0.87, 95% CI: 0.78-0.97). The results suggested that p53 codon 72 polymorphism may contribute to susceptibility to breast cancer, especially in Europeans. Additional well-designed large studies were required to validate this association in different populations.

Patterns of treatment for early stage breast cancers at the M. D. Anderson Cancer Center from 1997 to 2004

BACKGROUND

The objectives of this study were to examine the patterns of use for adjuvant therapy and the changes in surgical practice for patients with early stage breast cancer and to describe how recent large clinical trial results impacted the patterns of care at The University of Texas M. D. Anderson Cancer Center (MDACC).

METHODS

The study included 5486 women who were diagnosed with stage I through IIIA breast cancer between 1997 and 2004 and received their treatment at MDACC. A chi-square trend test and multivariate logistic regression model were used to assess changes in treatment patterns over time.

RESULTS

Among lymph node-positive patients, the use of anthracycline plus taxane chemotherapy increased from 17% in 1997 to 81% in 2004 (P < .001). Meanwhile, the use of anthracyclines without taxanes dropped from 76% to 20% (P < .001) between 1997 and 2000. For postmenopausal patients who received endocrine therapy, the use of tamoxifen was replaced increasingly by the use of aromatase inhibitors (from 100% on tamoxifen in 1997 to 14% in 2004; P < .001). The percentage of women who underwent initial sentinel lymph node biopsy increased significantly during the period from 1997 to 2004 (from 1.8% to 69.7%, respectively, among patients who underwent mastectomy; and from 18.1% to 87.1%, respectively, among patients who underwent breast-conserving surgery; P < .001).

CONCLUSIONS

The results from this study suggested that key findings from adjuvant therapy and surgical procedures from large clinical trials often prompt immediate changes in the patient care practices of research hospitals like MDACC.

Incidence of invasive breast cancer in postmenopausal women after discontinuation of long-term raloxifene administration

BACKGROUND

Postmenopausal women with osteoporosis had a 66% relative risk reduction for invasive breast cancer over 8 years of raloxifene therapy in the randomized, placebo-controlled 4-year MORE (Multiple Outcomes of Raloxifene Evaluation) trial and the CORE (Continuing Outcomes Relevant to Evista) trial, a 4-year follow-up to MORE.

PATIENTS AND METHODS

The first post hoc analysis examined the effects of raloxifene on the cumulative incidence of invasive breast cancer on a yearly basis. Another analysis compared the incidence of invasive breast cancer in 3967 patients who continued raloxifene for 8 years (RLX-C, n = 2280), discontinued raloxifene after 4 years in MORE (RLX-D, n = 401), or took placebo (n = 1286) for a mean 2.9 years' treatment duration (57,338 patient-years).

RESULTS

The unadjusted breast cancer incidence rate was 5.39 per 1000 patient-years in the placebo group compared with 2.26 in the RLX-C group (hazard ratio [HR], 0.41 [95% CI 0.21-0.81]) and 3.59 in the RLX-D group (HR, 0.69 [95% CI 0.23-2.01]). Because the choice of taking the study drug was not randomized in CORE, propensity scores were used to adjust for potential imbalances in baseline characteristics before CORE. Results after adjustment by the propensity score method were similar to the unadjusted results.

CONCLUSION

This analysis suggests a persistent effect for breast cancer risk reduction in patients who discontinued raloxifene, although this conclusion is limited by the small sample size.

Multiple primary tumours: incidence estimation in the presence of competing risks

BACKGROUND

Estimating the risk of developing subsequent primary tumours in a population is difficult since the occurrence probability is conditioned to the survival probability.

METHODS

We proposed to apply Markov models studying the transition intensities from first to second tumour with the Aalen-Johansen (AJ) estimators, as usually done in competing risk models. In a simulation study we applied the proposed method in different settings with constant or varying underlying intensities and applying age standardisation. In addition, we illustrated the method with data on breast cancer from the Piedmont Cancer Registry.

RESULTS

The simulation study showed that the person-years approach led to a sensibly wider bias than the AJ estimators. The largest bias was observed assuming constantly increasing incidence rates. However, this situation is rather uncommon dealing with subsequent tumours incidence. In 9233 cases with breast cancer occurred in women resident in Turin, Italy, between 1985 and 1998 we observed a significant increased risk of 1.91 for subsequent cancer of corpus uteri, estimated with the age-standardised Aalen-Johansen incidence ratio (AJ-IRstand), and a significant increased risk of 1.29 for cancer possibly related to the radiotherapy of breast cancer. The peak of occurrence of those cancers was observed after 8 years of follow-up.

CONCLUSION

The increased risk of a cancer of the corpus uteri, also observed in other studies, is usually interpreted as the common shared risk factors such as low parity, early menarche and late onset of menopause. We also grouped together those cancers possibly associated to a previous local radiotherapy: the cumulative risk at 14 years is still not significant, however the AJ estimators showed a significant risk peak between the eighth and the ninth year. Finally, the proposed approach has been shown to be reliable and informative under several aspects. It allowed for a correct estimation of the risk, and for investigating the time trend of the subsequent cancer occurrence.

Do viruses cause breast cancer?

Because mouse mammary tumor virus (MMTV; the Bittner virus) is the proven cause of breast cancer in both field and experimental mice, similar viruses have long been suspects as a potential cause of human breast cancer. MMTV-like viral genetic material has been identified in human breast tumors, but there is no definitive evidence whether MMTV is causal and not merely an innocuous infection in humans. High-risk human papilloma viruses (HPVs), Epstein-Barr (EBV), and other viruses also have been identified in human breast tumors, but again there is no definitive evidence for a causal role. Any viral hypothesis as a cause of breast cancer must take into account the most striking epidemiologic feature of human breast cancer, the three- to sixfold differences in mortality and up to eightfold differences in incidence between some Asian and Western populations. These differences dramatically lessen to a two- to threefold difference within one or two generations of migration of females from low to high risk of breast cancer countries. In this chapter, a plausible explanation for these phenomena is offered; that is, the hypothesis that oncogenic viruses such as MMTV and high-risk HPVs may initiate some breast cancers in most populations. Furthermore, dietary patterns are suggested to determine circulating sex hormone levels, which in turn promote the replication of the hormone-dependent viruses MMTV and HPV. In addition, diet and hormones promote growth of both normal and malignant cells. Finally, the hypothesis that migrants from low to high risk of breast cancer countries change their food consumption patterns is suggested, which leads to higher circulating hormone levels, which in turn promotes viral replication, which initiates breast oncogenesis, which is enhanced by sex and growth hormones.

Laser optoacoustic imaging system for detection of breast cancer

We designed, fabricated and tested the laser optoacoustic imaging system for breast cancer detection (LOIS-64), which fuses optical and acoustic imaging techniques in one modality by utilizing pulsed optical illumination and ultrawide-band ultrasonic detection of resulting optoacoustic (OA) signals. The system was designed to image a single breast slice in craniocaudal or mediolateral projection with an arc-shaped array of 64 ultrawide-band acoustic transducers. The system resolution on breast phantoms was at least 0.5 mm. The single-channel sensitivity of 1.66 mVPa was estimated to be sufficient for single-pulse imaging of 6 to 11 mm tumors through the whole imaging slice of the breast. The implemented signal processing using the wavelet transform allowed significant reduction of the low-frequency (LF) acoustic noise, allowed localization of the optoacoustic signals from tumors, and enhanced the contrast and sharpened the boundaries of the optoacoustic images of the tumors. During the preliminary clinical studies on 27 patients, the LOIS-64 was able to visualize 18 out of 20 malignant lesions suspected from mammography and ultrasound images and confirmed by the biopsy performed after the optoacoustic tomography (OAT) procedure.

Tumor-infiltrating lymphocytes predict response to neoadjuvant chemotherapy in patients with breast carcinoma

Tumor-infiltrating leukocytes and other immunohistochemical parameters were evaluated in pretherapeutic biopsies and resection specimens in 73 patients undergoing neoadjuvant chemotherapy with doxorubicin and paclitaxel. Ten patients with pathological complete response had significantly higher p53 expression, CD3(+) lymphocyte and CD83(+) cell counts, and lower progesterone receptor expression. In the remaining 63 patients, a significant decrease in the percentage of Ki-67, vascular endothelial growth factor expression, CD68(+) monocytes, and increased CD31(+), CD34(+), and SMA(+) stromal vessels, maximal CD3(+) and CD56(+) lymphocyte, maximal and mean CD83(+) cell, maximal CD1a(+), and maximal and mean S100(+) cell counts were observed after neoadjuvant chemotherapy.

Factors influencing women in seeking help from a health care professional on self discovery of a breast symptom, in an Irish context

AIM

To identify the extent of delay and the factors influencing women in seeking help from a health care professional on self discovery of a breast symptom, in an Irish context.

BACKGROUND

Breast cancer is the most common malignancy among women in the developed world. In Ireland, 2700 women are diagnosed with breast cancer and over 900 die from it annually. A longer delay in presenting with breast symptoms is associated with a lower rate of survival from breast cancer. However, many women wait for longer than three months before presenting to a health care professional on self discovery of a breast symptom.

DESIGN

A quantitative correlational design was used.

METHODS

Data were collected using the 'Women's help seeking for breast symptoms' questionnaire. Women were recruited in the breast clinic prior to their visit with the consultant.

RESULTS

A total of 100 women participated, 99 of whom fully completed the questionnaire. Mean age was 40 years. It was found that 72.7% (n = 73) of women visited their GP within one month, 14.1% (n = 14) within one to three months and 10% (n = 12) after three months. Delay time was significantly related to women's knowledge and beliefs and social issues. Conversely, help seeking also correlated to women's knowledge and beliefs about the symptom and the anxiety surrounding the initial symptom discovery period.

CONCLUSION

Despite breast health promotion campaigns, many women delay for one month or more, in seeking help from a health care professional for self discovered breast symptoms. Prolonged delay has potential to impact on survival from breast cancer. This highlights the need for continued education and breast health promotion for women.

RELEVANCE TO CLINICAL PRACTICE

Health care professionals need to be aware of possible reasons for delay in seeking help for self discovered breast symptoms and explore new ways to address these barriers.

Sphere of equivalence--a novel target volume concept for intraoperative radiotherapy using low-energy X rays

PURPOSE

Accelerated partial breast radiotherapy with low-energy photons from a miniature X-ray machine is undergoing a randomized clinical trial (Targeted Intra-operative Radiation Therapy [TARGIT]) in a selected subgroup of patients treated with breast-conserving surgery. The steep radial dose gradient implies reduced tumor cell control with increasing depth in the tumor bed. The purpose was to compare the expected risk of local recurrence in this nonuniform radiation field with that after conventional external beam radiotherapy.

METHODS AND MATERIALS

The relative biologic effectiveness of low-energy photons was modeled using the linear-quadratic formalism including repair of sublethal lesions during protracted irradiation. Doses of 50-kV X-rays (Intrabeam) were converted to equivalent fractionated doses, EQD2, as function of depth in the tumor bed. The probability of local control was estimated using a logistic dose-response relationship fitted to clinical data from fractionated radiotherapy.

RESULTS

The model calculations show that, for a cohort of patients, the increase in local control in the high-dose region near the applicator partly compensates the reduction of local control at greater distances. Thus a "sphere of equivalence" exists within which the risk of recurrence is equal to that after external fractionated radiotherapy. The spatial distribution of recurrences inside this sphere will be different from that after conventional radiotherapy.

CONCLUSIONS

A novel target volume concept is presented here. The incidence of recurrences arising in the tumor bed around the excised tumor will test the validity of this concept and the efficacy of the treatment. Recurrences elsewhere will have implications for the rationale of TARGIT.

The costs of breast cancer in a Mexican public health institution

Breast cancer (BC) is the second leading cause of death as a result of neoplasia in Mexico. This study aimed to identify the direct and indirect costs of treating female outpatients diagnosed with BC at a Mexican public hospital. A cross-sectional, observational, analytical study was conducted. A total of 506 medical records were analyzed and 102 were included in the cost analysis. The micro-costing process was used to estimate treatment costs. A 17-item questionnaire was used to obtain information on direct and indirect costs. Of the 102 women with BC included in the study, 92.2% (94) were at Stage II, and only 7.8% at Stage I. Total direct costs over six months for the 82 women who had modified radical mastectomy (MRM) surgury were US$733,821.15. Total direct costs for the 15 patients with conservative surgery (CS) were US$138,190.39. We found that the total economic burden in the study population was much higher for patients with MRM than for patients with CS.

Proteomic analysis of breast cancer tissue reveals upregulation of actin-remodeling proteins and its relevance to cancer invasiveness

There is an emerging interest in protein expression profiling with the aim of identifying novel diagnostic markers and therapeutic targets in breast cancer. We analyzed breast cancer tissues by 2-D DIGE using a narrow range IPG strip (pH 5.5-6.7) after the immunodepletion of serum albumin and Ig. Sixty-three protein spots were detected with more than ±1.8-fold differences (p <0.05 for three technical replicates) from a set of tissue samples in which three tumor and three nontumor samples were randomly selected from six breast cancer subjects and pooled separately. Of these, 53 proteins were successfully identified by MS. Among the proteins whose levels were increased, we identified three novel WD-repeat-motif-bearing proteins that have been known to be involved in actin remodeling: Arp2/3 complex subunit 2 (p34-Arc), coronin-1A and WD-repeat protein 1 (Wdr1). Significantly increased amounts of p34-Arc and coronin-1A in breast cancer were also shown by Western blot analysis of matched tumor and nontumor tissue samples (N = 11, p <0.05), and were consistent with the mRNA levels retrieved from publicly available microarray databases. The siRNA knockdown of p34-Arc attenuated the invasion of SK-BR3 breast cancer cells into Matrigel. In contrast, the overexpression of coronin-1A increased this invasive activity. Taken together, the cellular levels of p34-Arc and coronin-1A were linked to cancer development and migration. The data obtained from the present study provides new insight into the management of breast cancer.

Association between NSAIDs use and breast cancer risk: a systematic review and meta-analysis

The association between non-steroidal anti-inflammatory drugs (NSAIDs) use and breast cancer has remained controversial. Therefore, an overall quantitative estimate of the association needs to be studied. A systematic review and meta-analysis was executed to explore the pooled estimate for relative risk (RR) and 95% confidence interval (CI) using random or fixed effects models based on heterogeneity analysis. Overall 26 studies with 528,705 participants were included. The RR of NSAIDs use and the incidence of breast cancer was 0.94 (95% CI: 0.88-1.00) with random effects model. A slight reduction of breast cancer by taking aspirin and ibuprofen was both observed with pooled RR of 0.91 (95% CI: 0.83-0.98) and 0.81 (95% CI: 0.67-0.97), respectively. Our results indicate that NSAIDs use is associated with a slight decrease for the development of breast cancer with a marginally statistical significant difference. The associations are slightly more obvious in aspirin and ibuprofen use.

Increased death risk and altered cancer incidence pattern in patients with isolated or combined autoimmune primary adrenocortical insufficiency

OBJECTIVES

Primary adrenocortical insufficiency is mostly caused by an autoimmune destruction of the adrenal cortex. The disease may appear isolated or as a part of an autoimmune polyendocrine syndrome (APS). APS1 is a rare hereditary disorder with a broad spectrum of clinical manifestations. In APS2, primary adrenocortical insufficiency is often combined with autoimmune thyroid disease and/or type 1 diabetes. We analysed mortality and cancer incidence in primary adrenocortical insufficiency patients during 40 years. Data were compared with the general Swedish population.

DESIGN AND PATIENTS

A population based cohort study including all patients with autoimmune primary adrenocortical insufficiency (3299) admitted to Swedish hospitals 1964-2004.

MEASUREMENTS

Mortality risk was calculated as the standardized mortality ratio (SMR) and cancer incidence as the standardized incidence ratio (SIR).

RESULTS

A more than 2-fold increased mortality risk was observed in both women (SMR 2.9, 95% CI 2.7-3.0) and men (SMR 2.5, 95% CI 2.3-2.7). Highest risks were observed in patients diagnosed in childhood. SMR was higher in APS1 patients (SMR 4.6, 95% CI 3.5-6.0) compared with patients with APS2 (SMR 2.1, 95% CI 1.9-2.4). Cancer incidence was increased (SIR 1.3, 95% CI 1.2-1.5). When tumours observed during the first year of follow-up were excluded, only the cancer risk among APS1 patients remained increased. Cause-specific cancer incidence analysis revealed significantly higher incidences of oral cancer, nonmelanoma skin cancer, and male genital system cancer among patients. Breast cancer incidence was lower than in the general population.

CONCLUSIONS

Our study shows a reduced life expectancy and altered cancer incidence pattern in patients with autoimmune primary adrenocortical insufficiency.

Breast cancer and hormonal therapy

Valid evidence from randomized-controlled trials indicates that breast cancer risk is increased with combined estrogen/progestogen use and that such treatment implies a risk greater than that of estrogen alone. Overall, risk estimates from observational studies are somewhat higher than in randomized-controlled trials but remain modest as compared with other risk factors even after long-term treatment. For combined estrogen/progestogen therapy, risk increases gradually to reach statistical significance after 4 to 5 years. Apart from its many beneficial health effects, the safety data for use of estrogen alone are quite reassuring. The only justifications for progestogen addition are for bleeding control and endometrial protection. At present, there are several new therapeutic compounds and concepts in development, which hold promise to provide both endometrial protection and breast safety.

A candidate molecular signature associated with tamoxifen failure in primary breast cancer

Introduction

Few markers are available that can predict response to tamoxifen treatment in estrogen receptor (ER)-positive breast cancers. Identification of such markers would be clinically useful. We attempted to identify molecular markers associated with tamoxifen failure in breast cancer.

Methods

Eighteen initially ER-positive patients treated with tamoxifen requiring salvage surgery (tamoxifen failure [TF] patients) were compared with 17 patients who were disease free 5 years after surgery plus tamoxifen adjuvant therapy (control patients). cDNA microarray, real-time quantitative PCR, and immunohistochemistry on tissue microarrays were used to generate and confirm a gene signature associated with tamoxifen failure. An independent series of 33 breast tumor samples from patients who relapsed (n = 14) or did not relapse (n = 19) under tamoxifen treatment from a different geographic location was subsequently used to explore the gene expression signature identified.

Results

Using a screening set of 18 tumor samples (from eight control patients and 10 TF patients), a 47-gene signature discriminating between TF and control samples was identified using cDNA arrays. In addition to ESR1/ERα, the top-ranked genes selected by statistical cross-analyses were MET, FOS, SNCG, IGFBP4, and BCL2, which were subsequently validated in a larger set of tumor samples (from 17 control patients and 18 TF patients). Confirmation at the protein level by tissue microarray immunohistochemistry was observed for ER-α, γ-synuclein, and insulin-like growth factor binding protein 4 proteins in the 35 original samples. In an independent series of breast tumor samples (19 nonrelapsing and 14 relapsing), reduced expression of ESR1/ERα, IGFBP4, SNCG, BCL2, and FOS was observed in the relapsing group and was associated with a shorter overall survival. Low mRNA expression levels of ESR1/ERα, BCL2, and FOS were also associated with a shorter relapse-free survival (RFS). Using a Cox multivariate regression analysis, we identified BCL2 and FOS as independent prognostic markers associated with RFS. Finally, the BCL2/FOS signature was demonstrated to have more accurate prognostic value for RFS than ESR1/ERα alone (likelihood ratio test).

Conclusions

We identified molecular markers including a BCL2/FOS signature associated with tamoxifen failure; these markers may have clinical potential in the management of ER-positive breast cancer.

mTOR inhibition reverses acquired endocrine therapy resistance of breast cancer cells at the cell proliferation and gene-expression levels

Activation of the Akt/mammalian target of rapamycin (mTOR) pathway has been shown to be associated with resistance to endocrine therapy in estrogen receptor alpha (ERalpha)-positive breast cancer patients. Utmost importance is attached to strategies aimed at overcoming treatment resistance. In this context, this work aimed to investigate whether, in breast cancer cells, the use of an mTOR inhibitor would be sufficient to reverse the resistance acquired after exposure to endocrine therapy. The ERalpha-positive human breast adenocarcinoma derived-MCF-7 cells used in this study have acquired both cross-resistance to hydroxy-tamoxifen (OH-Tam) and to fulvestrant and strong activation of the Akt/mTOR pathway. Cell proliferation tests in control cells demonstrated that the mTOR inhibitor rapamycin enhanced cell sensitivity to endocrine therapy when combined to OH-Tam or to fulvestrant. In resistant cells, rapamycin used alone greatly inhibited cell proliferation and reversed resistance to endocrine therapy by blocking the agonist-like activity of OH-Tam on cell proliferation and bypassing fulvestrant resistance. Reversion of resistance by rapamycin was associated with increased ERalpha protein expression levels and modification of the balance of phospho-ser167 ERalpha/total ERalpha ratio. Pangenomic DNA array experiments demonstrated that the cotreatment of resistant cells with fulvestrant and rapamycin allowed the restoration of 40% of the fulvestrant gene-expression signature. Taken together, data presented herein strongly support the idea that mTOR inhibitor might be one of the promising therapeutic approaches for patients with ERalpha-positive endocrine therapy-resistant breast cancers.

Epigenetic reprogramming of breast cancer cells by valproic acid occurs regardless of estrogen receptor status

Estrogen receptors (ERs) are a recognized prognostic factor and therapeutic target in breast cancer. The loss of ER expression relates to poor prognosis, poor clinical outcome and impairs the use of anti-estrogenic treatment. Histone deacetylase inhibitors are candidate drugs for cancer therapy. Among them, valproic acid (VPA) is a long used and safe anti-epileptic drug. We studied the biological consequences of the chromatin remodeling action of VPA in a normal human mammary epithelial cell line and in ERalpha-positive and ERalpha-negative breast cancer cell lines. In these cells and regardless of their ER status, VPA-induced cell differentiation, as shown by increased milk lipids production, decreased expression of the CD44 antigen and growth arrest in the G(0)-G(1) phase of the cell cycle. These effects were accompanied by decreased Rb phosphorylation, hyperacetylation of the p21(WAF1/CIP1) gene promoter and increased p21 protein expression. Only in breast cancer cells, cyclin B1 expression was decreased and the cells accumulated also in G(2). ERalpha expression decreased in ERalpha-positive, increased in ERalpha-negative and was unchanged in normal mammary epithelial cells, as did the expression of progesterone receptor, a physiological ERalpha target. VPA decreased the expression of the invasiveness marker pS2 in ERalpha-positive breast cancer cells, but did not cause its re-expression in ERalpha-negative cells. Overall, these data suggest that in both ERalpha-positive and -negative malignant mammary epithelial cells VPA reprograms the cells to a more differentiated and "physiologic" phenotype that may improve the sensitivity to endocrine therapy and/or chemotherapy in breast cancer patients.

Reduced incidence of invasive breast cancer with raloxifene among women at increased coronary risk

BACKGROUND

In the Raloxifene Use for The Heart trial, 10 101 postmenopausal women with coronary heart disease (CHD) or multiple CHD risk factors were randomly assigned to 60 mg/d raloxifene or to placebo and followed for a median of 5.6 years. Raloxifene, a selective estrogen receptor modulator, was found to reduce the risk of invasive breast cancer and vertebral fractures but not the risk of cardiovascular events. Here, we provide further details about breast cancer incidence by tumor characteristics, duration of treatment, and subgroup.

METHODS

Reported breast cancer was adjudicated by an independent committee based on medical records and pathology reports. The primary analyses used Cox proportional hazards models with time to first breast cancer as the outcome. Subgroup effects were analyzed using similar models with terms for treatment by subgroup. All statistical tests were two-sided.

RESULTS

As previously reported, raloxifene reduced the incidence of invasive breast cancer by 44% (hazard ratio [HR] = 0.56; 95% confidence interval [CI] = 0.38 to 0.83; absolute risk reduction = 1.2 invasive breast cancers per 1000 women treated for 1 year). The lower incidence of invasive breast cancer reflected a 55% lower incidence of invasive estrogen receptor (ER)-positive tumors (HR = 0.45; 95% CI = 0.28 to 0.72). However, raloxifene treatment did not reduce the incidence of noninvasive breast cancer or of invasive ER-negative breast cancer. The reduced incidence of invasive breast cancer was similar across subgroups, including those defined by age, body mass index, family history of breast cancer, prior use of postmenopausal hormones, and 5-year estimated risk of invasive breast cancer.

CONCLUSION

Raloxifene reduces risk of invasive ER-positive breast cancer regardless of a woman's baseline breast cancer risk but does not reduce risk of noninvasive or ER-negative breast cancers. These results confirm those of the Multiple Outcomes of Raloxifene Evaluation, a previous randomized trial among women with osteoporosis.

Development and verification of a prediction model using serum tumor markers to predict the response to chemotherapy of patients with metastatic or recurrent breast cancer

PURPOSE

The aim of this study was to develop a prediction model using serum tumor markers to predict the response to chemotherapy of patients with metastatic or recurrent breast cancer.

METHODS

We retrospectively analyzed a training set of 105 patients with metastatic or recurrent breast cancer. Their chemotherapeutic response had been evaluated according to the World Health Organization (WHO)'s response criteria. Our model for predicting response using carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 15-3, and NCC-ST-439 was determined using the area under the receiver operating characteristic curve (ROC-AUC) and the overall misclassification rate (OMR) in a random cross-validation. The prediction model was then verified in a consecutive set of 64 patients. Their response had been evaluated using the response evaluation criteria in solid tumors (RECIST) criteria.

RESULTS

The best prediction model consisted of the serum CEA, CA15-3, and NCC-ST-439 levels, but the prediction formula varied according to the baseline CA15-3 level (elevated or normal). The overall ROC-AUC and OMR in the training set were 0.83 and 0.19, respectively. The overall ROC-AUC and OMR in the verification set were 0.72 and 0.28, respectively. When the verification set was stratified according to either the objective response or the predicted response, the time-to-progression, but not the overall survival, was significantly different.

CONCLUSION

Our model for predicting the response to first-line chemotherapy of patients with metastatic or recurrent breast cancer may be valid because it predicted the outcome of more than 70% of the patients in an independent verification set.

Identification of the xenobiotic-metabolizing enzyme arylamine N-acetyltransferase 1 as a new target of cisplatin in breast cancer cells: molecular and cellular mechanisms of inhibition

Arylamine N-acetyltransferase 1 (NAT1) is a phase II xenobiotic-metabolizing enzyme that plays an important role in the biotransformation of aromatic drugs and carcinogens. NAT1 activity has long been associated with susceptibility to various cancers. Evidence for a role of NAT1 in malignant progression has also been obtained, particularly for breast and prostate cancer. Cisplatin is widely used in chemotherapy against human cancers, and it is thought to act principally by forming DNA adducts. However, recent studies have suggested that some of the pharmacological and/or toxicological effects of cisplatin may be due to the direct targeting and inhibition of certain cellular enzymes. We show here that the exposure of breast cancer cells, known to express functional NAT1 enzyme, to therapeutically relevant concentrations of cisplatin impairs the catalytic activity of endogenous NAT1. Endogenous NAT1 was also found to be inactivated, in vivo, in the tissues of mice treated with cisplatin. Mechanistic studies with purified human NAT1 indicated that this inhibition resulted from the irreversible formation of a cisplatin adduct with the active-site cysteine residue of the enzyme. Kinetic studies suggested that NAT1 interacts rapidly with cisplatin, with a second-order rate inhibition constant of 700 M(-1) min(-1). This rate constant is one the highest ever reported for the reaction of cisplatin with a biological macromolecule. Few enzymes have been clearly shown to be inactivated by cisplatin. We provide here molecular and cellular evidence suggesting that NAT1 is one of the targets of cisplatin in cells.

Preclinical development of a neutral, estrogen receptor-targeted, tridentate 99mTc(I)-estradiol-pyridin-2-yl hydrazine derivative for imaging of breast and endometrial cancers

Breast and endometrial cancers are the most common invasive malignancies in women, with more than 217,000 new diagnoses per year in the United States. These cancers are often classified into 2 subtypes based on the expression of the classical estrogen receptor. In this study, we describe a new structural class of neutral tridentate 99mTc(I)-estradiol-pyridin-2-yl hydrazine derivatives for potential use in breast and endometrial cancer imaging.

METHODS

The 99mTc(I)-estradiol-pyridin-2-yl hydrazine derivative was synthesized via the Sonogashira cross-coupling reaction and radiolabeled via the tricarbonyl approach. Radiochemical purity was assessed by high-performance liquid chromatography. Cell-binding studies were performed with human breast adenocarcinoma MCF-7 cells. The in vivo biodistribution of the 99mTc(I) derivative was evaluated in virgin female C57BL/6 mice in defined phases of the estrous cycle. Biodistribution and SPECT/CT studies were performed with mice bearing MCF-7 and primary human endometrial tumors.

RESULTS

Radiochemical analysis demonstrated that the postpurification purity of the 99mTc(I)-estradiol-pyridin-2-yl hydrazine derivative was > or =95%, with a specific activity of 99mTc of 47.5 TBq/mmol. Cell-binding studies yielded a dissociation constant (mean +/- SEM) of 11 +/- 1.5 nM. In vivo studies revealed that receptor-mediated uptake was present in all phases of the estrous cycle in reproductive organs and mammary glands but was highest during the diestrous phase of the estrous cycle. Despite high nonspecific uptake in the liver, significant receptor-mediated uptake was observed in target tissues and estrogen receptor-expressing tumors (0.67% for MCF-7 tumors and 0.77% for endometrial tumors). Tumor uptake was reduced by approximately 50% on coinjection with 17beta-estradiol.

CONCLUSION

We have characterized a novel neutral tridentate 99mTc(I)-estradiol-pyridin-2-yl hydrazine derivative for potential use in breast and endometrial cancer imaging. This study represents the first step on a path toward the design of estrogen-based Tc-labeled tracers with improved targeting and SPECT imaging characteristics.

Selective estrogen receptor modulators: an update on recent clinical findings

Recent clinical data on selective estrogen receptor modulators (SERMs) have provided the basis for reassessment of the SERM concept. The molecular basis of SERM activity involves binding of the ligand SERM to the estrogen receptor (ER), causing conformational changes which facilitate interactions with coactivator or corepressor proteins, and subsequently initiate or suppress transcription of target genes. SERM activity is intrinsic to each ER ligand, which accomplishes its unique profile by specific interactions in the target cell, leading to tissue selective actions. We discuss the estrogenic and anti-estrogenic effects of early SERMs, such as clomiphene citrate, used for treatment of ovulation induction, and the triphenylethylene, tamoxifen, which has ER antagonist activity in the breast, and is used for prevention and treatment of ER-positive breast cancer. Since the development of tamoxifen, other triphenylethylene SERMs have been studied for breast cancer prevention, including droloxifene, idoxifene, toremifene, and ospemifene. Other SERMs have entered clinical development more recently, including benzothiophenes (raloxifene and arzoxifene), benzopyrans (ormeloxifene, levormeloxifene, and EM-800), lasofoxifene, pipendoxifene, bazedoxifene, HMR-3339, and fulvestrant, an anti-estrogen which is approved for breast cancer treatment. SERMs have effects on tissues containing ER, such as the breast, bone, uterine and genitourinary tissues, and brain, and on markers of cardiovascular risk. Current evidence indicates that each SERM has a unique array of clinical activities. Differences in the patterns of action of SERMs suggest that each clinical end point must be evaluated individually, and conclusions about any particular SERM can only be established through appropriate clinical trials.

Treatment of advanced hormone-sensitive breast cancer in postmenopausal women with exemestane alone or in combination with celecoxib

PURPOSE

Preclinical data showed that the combination of exemestane and celecoxib has synergistic effects. Therefore, a study was undertaken to explore the efficacy and tolerability of this combination in postmenopausal patients with advanced, hormone-sensitive breast cancer.

PATIENTS AND METHODS

A randomized phase II study was conducted in postmenopausal patients with hormone-sensitive breast cancer and measurable disease who had progressive disease after treatment with tamoxifen. Patients were randomly assigned to either exemestane 25 mg daily or the combination of exemestane 25 mg daily with celecoxib 400 mg twice daily. Response Evaluation Criteria in Solid Tumors Group criteria were used to determine antitumor efficacy. Primary end point was the rate of clinical benefit. Secondary end points were tolerability, objective response rate, time to progression (TTP), and duration of clinical benefit. A pharmacodynamic and a pharmacokinetic study were conducted in parallel.

RESULTS

One hundred eleven patients (exemestane, n = 55; combination, n = 56) were enrolled in 2002. The demographic characteristics and prognostic factors were similar in both arms. In the assessable population, 24 of 51 patients in the combination arm and 24 of 49 patients in the exemestane arm achieved clinical benefit. TTP was similar in both groups. Duration of clinical benefit was longer in the combination group (median, 96.6 v 49.1 weeks). The addition of celecoxib did not change the tolerability profile of exemestane alone.

CONCLUSION

Similar rates of clinical benefit were achieved in both groups.

Accuracy of computed tomography perfusion in assessing metastatic involvement of enlarged axillary lymph nodes in patients with breast cancer

INTRODUCTION

The purpose of this study was to evaluate the diagnostic accuracy of computed tomography (CT) perfusion in differentiating metastatic from inflammatory enlarged axillary lymph nodes in patients with breast cancer.

METHODS

Twenty-five patients with 26 locally advanced breast tumors and clinically palpable axillary lymph nodes underwent dynamic multi-detector CT (LightSpeed 16; General Electric Company) at one scan per second for 150 seconds at the same table position after 40 ml intravenous contrast injection at 4.0 ml/second. Semi-automatic calculation of values of perfusion parameters - blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS) - was performed. Results were compared with pathology and with Her-2/neu and Ki-67 levels in a surgical specimen of the primary tumor.

RESULTS

Examined lymph nodes were inflammatory in 8 cases and metastatic in 18. Mean values of perfusion parameters in inflammatory and metastatic nodes, respectively, were BF of 76.18 (confidence interval [CI], 31.53) and 161.60 (CI, 40.94) ml/100 mg per minute (p < 0.05), BV of 5.81 (CI, 2.50) and 9.15 (CI, 3.02) ml/100 mg (not significant [n.s.]), MTT of 6.80 (CI, 1.55) and 5.50 (CI, 1.84) seconds (p = 0.07), and PS of 25.82 (CI, 4.62) and 25.96 (CI, 7.47) ml/100 mg per minute (n.s.). Size of nodes, stage of breast cancer, Ki-67 and Her-2/neu levels in breast cancer, and expression of primary tumor activity were not correlated to any perfusion parameter in metastatic nodes.

CONCLUSION

CT perfusion might be an effective tool for studying enlarged axillary lymph nodes in patients with breast cancer. It gives information on vascularization of lymph nodes, helping to understand the changes occurring when neoplastic cells implant in lymph nodes.

Multiparity and the risk of premenopausal breast cancer: different effects across ethnic groups in Singapore

BACKGROUND

The relationship between multiparity and premenopausal breast cancer risk is different in Caucasian, African-American and Hispanic women. For Asian women, this relationship has never been well studied.

METHODS

Within the Singapore Birth Registry, we selected all women who had a first child between 1986 and 2002 (169,936 Chinese, 40,521 Malay, 17,966 Indian). We linked them to the Singapore Cancer Registry data to identify those who developed breast cancer after childbirth (n = 527). We used multivariate Cox analysis to examine the relationship between parity, ethnicity and premenopausal breast cancer risk.

RESULTS

Compared to Chinese, Malay women had increased and Indian women had decreased risks of premenopausal breast cancer (adjusted Hazard Ratios [HRadj] 1.25 [1.0-1.6] and 0.48 [0.3-0.8] respectively). Multiparity did not modify the risk of premenopausal breast cancer in Chinese and Indians. In Malays there was a significant risk reduction with increasing parity (P (trend )0.037). Malay women with one, two and >or=3 children had premenopausal breast cancer risks (HR(adj)) of 1.86 (1.2-3.0), 1.52 (1.1-2.2) and 0.87 (0.6-1.3) respectively compared to their Chinese counterparts.

CONCLUSIONS

The impact of multiparity on premenopausal breast cancer risk differs across ethnic groups in Singapore. Increasing parity reduces the risk of premenopausal breast cancer in Malay, but not in Chinese and Indian women. Uniparous Malay women have twice the risk of premenopausal breast cancer compared to uniparous Chinese. This excess risk disappears after giving birth to >or=3 children. Indian women have lower premenopausal breast cancer risks than Chinese, regardless of their parity status.

Changes in breast cancer incidence and mortality in middle-aged and elderly women in 28 countries with Caucasian majority populations

BACKGROUND

Mammography screening and menopause hormone therapy is essentially offered to women 50-69 years old.

METHODS

In 28 European ancestry countries, we quantified changes in breast cancer incidence and mortality using a joinpoint regression analysis from 1960 until last year of available data.

RESULTS

Since 1960, increases in incidence often in the order of 2%-3% per year occurred in all countries, mainly in women 50-69 years old whose incidence in eight countries surpassed the incidence in women 70 years old and more. In 10 countries, a decrease in incidence in women >or=70 years was noticeable in the last years of observation, but the magnitude of this decrease was far from matching the magnitude of the increases observed in the 50-69 age-group. In the beginning of years 2000s, a persistent decrease in mortality of approximately 2% per year was observed in women 50-69 years old in most countries and parallel declines in mortality were observed in women 70 years or more.

CONCLUSIONS

In years 2000s, in a number of countries, the incidence of breast cancer has become greater in middle-aged women than in older women. If trends remain unchanged, the same phenomenon is likely to happen in other countries.

Variations in breast cancer incidence per decade of life (Goiânia, GO, Brazil): 16-year analysis

OBJECTIVE

To analyze the variation in breast cancer incidence, with stratification into ten-year age groups, 17 years after the nuclear accident in Goiânia.

METHODS

Between 1988 and 2003, 3312 new cases were recorded. The crude and standardized incidence rates were calculated. ANOVA was used to obtain the coefficient of determination (R2) for the incidence over the course of the years, and p-values were obtained both by linear and by polynomial regression.

RESULTS

The increases in crude and standardized incidence were statistically significant in all age groups, except for women between 20 and 29 years old. For the age group from 30 to 49 years, the increase in incidence was around 100% (p = 0.001), and from 50 to 59 years, 277% (p < 0.001). More modest increases of around 50% were observed in the age groups from 60 to 79 years (p = 0.013). For the women aged 80 years and over, the increase was 272% (p = 0.015).

CONCLUSIONS

There were significant increases in the crude and standardized incidence rates for breast cancer in the city of Goiânia. The women in the age group from 50 to 59 years were the ones who presented the highest increase in incidence. More wide-ranging epidemiological studies therefore become necessary for defining the factors that are possibly related to this excessive increase in breast cancer incidence, in certain specific segments of the female population.

Genetic changes of p53, K-ras, and microsatellite instability in gallbladder carcinoma in high-incidence areas of Japan and Hungary

AIM: To disclose geographic differences in genetic changes involved in gallbladder carcinogenesis between two distinct high-incidence areas of Japan and Hungary.

METHODS: We examined 42 cases of gallbladder carcinoma: 22 Japanese and 20 Hungarian cases. p53 mutations at exons 5 to 8 and K-ras mutations at codon 12 were tested by direct sequencing. Microsatellite instability was determined from fluorescent dye-labeled PCR amplifications of five-microsatellite markers (BAT-25, BAT-26, D2S123, D5S346, and D17S250).

RESULTS: Mutations of p53 were detected in 11 of 22 Japanese cases and 6 of 18 Hungarian cases (11/22 vs 6/18, P = 0.348). Transition at CpG sites was found in none of 11 Japanese cases and 2 of 6 Hungarian cases; the difference was marginally significant (0/11 vs 2/6, P = 0.110). K-ras mutations were detected in only one of the Hungarian cases. Eight of 19 (42.1%) Japanese cases were MSI-high (presence of novel peaks in more than one of the five loci analyzed), whereas only 1 of 15 (6.7%) Hungarian cases was MSI-high (P = 0.047).

CONCLUSION: It appears that the p53 mutations and MSI differ in patients with gallbladder carcinoma between two distinct high-incidence areas. Geographic variation might exist in the process of gallbladder carcinogenesis.

RNA interference (RNAi)-mediated vascular endothelial growth factor-C (VEGF-C) reduction interferes with lymphangiogenesis and enhances epirubicin sensitivity of breast cancer cells

It has been reported that over-expression of vascular endothelial growth factor-C (VEGF-C) in tumors leads to increased lymphangiogenesis and resistance to chemotherapy. Therefore, we hypothesized that VEGF-C would be a good molecular target for cancer gene therapy. In this study, we silenced the expression of VEGF-C with the highly specific post-transcriptional suppression of RNA interference (RNAi) in human breast cancer MCF-7 cell line. The expression of VEGF-C was examined by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), and the effect of plasmid on human lymphatic endothelial cells (HLECs) in vitro was analyzed by migration and 3-(4, 5-dimethylt-hiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The sensitivity to anticancer agents was evaluated by MTT and apoptosis assay, and apoptosis-related genes bcl-2/bax ratio was determined by Western Blotting. Results showed that of three siRNA-expressing vectors, P-1/siRNA most significantly suppressed the expression of VEGF-C mRNA and protein (38.1% of control and 117.8 +/- 24.2 pg/ml, respectively) and interfered with proliferation and migration of HLECs in vitro. Moreover, transfection of VEGF-C/siRNA combined with Epirubicin markedly decreased breast cancer cells viability, reaching up to 38.5%, and increased apoptosis rate from 13.1% to 38.9%, as determined by decrease of bcl-2/bax ratio. In summary, VEGF-C would be a good molecular target, and a combination of Epirubicin and RNAi targeting VEGF-C could be an effective means for suppressing lymphatic metastasis and enhancing chemosensitivity of human breast cancer cells.