Breast cancer statistics, 2013

PI3K/AKT/mTOR pathway inhibitors: the ideal combination partners for breast cancer therapies?

Activation of the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR pathway is common in breast cancer. PI3K pathway activation has been associated with tumor growth and progression, and thus is a promising target for breast cancer therapy. Agents targeting the PI3K pathway can restore sensitivity to standard breast cancer therapies, including endocrine, HER2-targeted agents and chemotherapy, by suppressing PI3K pathway activation, which is central to the development of therapeutic resistance. The combination of endocrine therapy and PI3K pathway (mTOR) inhibition has proven clinical benefit, and novel combination strategies involving PI3K pathway inhibitors and other investigational targeted therapies are now being explored clinically in patients with breast cancer.

Racial and ethnic disparities in the diagnosis of breast cancer: changes in presenting stage in minority populations in Florida during 1981-2009

We assessed whether presenting breast cancer stage has changed over time in Florida, and whether there is variation in this change with respect to race, ethnicity, and socioeconomic status (SES). Data were obtained from the Florida Cancer Data System. We included females with invasive breast cancer and complete information on race, ethnicity, and SES during 1981-2009 (n = 226,651). Associations between categorical variables were examined using Chi-square tests. Predictors of SEER stage at diagnosis (local, regional, and distant) were modeled with multinomial ordinal logistic regression models. There was a significant increase in local disease and a decrease in regional and distant disease at presentation (p < 0.0001) over the time period assessed. Compared to whites, black patients continue to have lower odds of local presentation (OR 0.73, 95% CI 0.63, 0.85), as do Hispanic patients (OR 0.80, 95% CI 0.76, 0.84) compared to non-Hispanics. The increase in local stage at diagnosis was greater for black than white patients, as was the decrease in regional and distant disease (p < 0.001). Hispanic women also had significant increase in localized disease and decrease in regional and distant disease (p < 0.001), but there was little difference in the change compared to non-Hispanic women. Localized breast cancer stage at diagnosis has become more common over time in all groups. Significant disparity persists, with black and Hispanic patients being less likely to present with localized disease than white patients overall. There was a greater change for black versus white patients, resulting in a narrowing in the racial gap in stage at diagnosis.

Stereotactic body radiotherapy as primary therapy for head and neck cancer in the elderly or patients with poor performance

OBJECTIVE

Stereotactic body radiotherapy (SBRT) is increasingly used to treat a variety of tumors, including head and neck squamous cell carcinoma (HNSCC) in the recurrent setting. While there are published data for re-irradiation using SBRT for HNSCC, there are limited data supporting its use as upfront treatment for locally advanced disease.

STUDY DESIGN/METHODS

Here, we describe three patients who received SBRT as the primary treatment for their HNSCC along with a review of the current literature and discussion of future pathways.

RESULTS

The three cases discussed tolerated treatment well with manageable acute toxicities and had either a clinical or radiographic complete response to therapy.

CONCLUSION

Head and neck squamous cell carcinoma presents a unique challenge in the elderly, where medical comorbidities make it difficult to tolerate conventional radiation, often given with a systemic sensitizer. For these individuals, providing a shortened course using SBRT may offer an effective alternative.

miRNA expression patterns in chemoresistant breast cancer tissues

BACKGROUND/AIMS

Breast cancer chemoresistance is a major obstacle to the successful treatment of patients. miRNAs perform critical roles in biological processes, including tumorigenesis and chemoresistance. However, little clinical data are available regarding the relationship between miRNA expression patterns and breast cancer chemoresistance.

METHODS

We created a doxorubicin-resistant MCF-7 (MCF-/Adr) cell line using a pulse-selection method; then verified the resistance of the MCF-7/Adr cell line to doxorubicin by using the methyl thiazolyl tetrazolium (MTT) assay, terminal deoxyribonucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) staining, and Intracellular doxorubicin accumulation assay. Then, we performed qRT-PCR to detect the expression patterns of 14 selected miRNAs (which are related to breast cancer resistance) in both cell lines. Subsequently, we performed a bioinformatics analysis, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, to determine the putative functions of 13 differentially expressed miRNA-targeted genes. Finally, we tested the expression levels of these 13 miRNAs in 10 chemotherapy non-responder breast cancer tissues and 29 responder tissues. All statistical analyses were performed by a two-tailed Student's t-test, and a P value less than 0.05 was considered statistically significant.

RESULTS

The results of the MTT assay showed that the MCF-7/Adr cell line was significantly more resistant to doxorubicin compared to the MCF-7 cells The results of the TUNEL assay indicated that doxorubicin induced an increase in the number apoptotic cells in the MCF-7 group. Additionally, the accumulation of doxorubicin was higher in MCF-7 cells compared to MCF-7/Adr cells, which was consistent with the MTT and TUNEL results. The qRT-PCR results demonstrated that compared to the parental MCF-7 cell line, miR-200a, miR-141, miR-200c, miR-31, miR-429, and miR-196b were over-expressed, and let-7e, miR-576-3p, miR-125b-1, miR-370, miR-145, miR-765, and miR-760 were significantly down-regulated in MCF-7/Adr cells. The GO analysis results revealed that the predicted target genes of these 14 miRNAs primarily regulated protein binding, zinc ion binding, DNA binding, and transcription factor activity. The KEGG data demonstrated that these target genes are mainly involved in the MAPK signaling pathway, regulation of the actin cytoskeleton, cytokine-cytokine receptor interaction, and other signaling pathways. Compared to the breast cancer tissues from chemotherapy responders, 10 miRNAs were identified to be dysregulated in the chemoresistant breast cancer tissues. Three of these miRNAs were up-regulated (miR-141, miR-200c, and miR-31), and 7 were down-regulated (let-7e, miR-576-3p, miR-125b-1, miR-370, miR-145, miR-765, and miR-760).

CONCLUSION

In this study, we identified 10 dysregulated miRNAs in both breast cancer cells and chemoresistant tissues, which might be biomarkers for the prognosis of breast cancer chemoresistance. Our study contributes to a comprehensive understanding of prognostic biomarkers during clinical treatment, and we hypothesize that the miRNA signatures of drug-resistant carcinoma tissues could be useful for developing new strategies for targeted therapies in patients with chemoresistant breast cancer.

The activation of G protein-coupled receptor 30 (GPR30) inhibits proliferation of estrogen receptor-negative breast cancer cells in vitro and in vivo

There is an urgent clinical need for safe and effective treatment agents and therapy targets for estrogen receptor negative (ER−) breast cancer. G protein-coupled receptor 30 (GPR30), which mediates non-genomic signaling of estrogen to regulate cell growth, is highly expressed in ER− breast cancer cells. We here showed that activation of GPR30 by the receptor-specific agonist G-1 inhibited the growth of ER− breast cancer cells in vitro. Treatment of ER− breast cancer cells with G-1 resulted in G2/M-phase arrest, downregulation of G2-checkpoint regulator cyclin B, and induction of mitochondrial-related apoptosis. The G-1 treatment increased expression of p53 and its phosphorylation levels at Serine 15, promoted its nuclear translocation, and inhibited its ubiquitylation, which mediated the growth arrest effects on cell proliferation. Further, the G-1 induced sustained activation and nuclear translocation of ERK1/2, which was mediated by GPR30/epidermal growth factor receptor (EGFR) signals, also mediated its inhibition effects of G-1. With extensive use of siRNA-knockdown experiments and inhibitors, we found that upregulation of p21 by the cross-talk of GPR30/EGFR and p53 was also involved in G-1-induced cell growth arrest. In vivo experiments showed that G-1 treatment significantly suppressed the growth of SkBr3 xenograft tumors and increased the survival rate, associated with proliferation suppression and upregulation of p53, p21 while downregulation of cyclin B. The discovery of multiple signal pathways mediated the suppression effects of G-1 makes it a promising candidate drug and lays the foundation for future development of GPR30-based therapies for ER− breast cancer treatment.

Effect of aromatase inhibition on serum levels of sclerostin and dickkopf-1, bone turnover markers and bone mineral density in women with breast cancer

PURPOSE

While their negative impact on bone health is well established, the effects of aromatase inhibition (AI) on Wnt inhibitors and osteoprotegerin (OPG) are unknown. The aim of the study was to investigate the effects of AI on serum levels of sclerostin, DKK-1 and OPG, as well as their associations with PINP and CTX as markers of bone turnover and bone mineral density (BMD) assessed by DXA.

METHODS

We conducted a prospective longitudinal analysis of 70 postmenopausal women with hormone receptor-positive early breast cancer (BC) treated with anastrozole. All measurements were performed at baseline, 12 and 24 months of treatment. We measured the association of the investigated variables with circulating bone turnover markers, as well as with the BMD.

RESULTS

After 24 months of AI therapy, sclerostin and OPG concentrations increased from 29.5 pmol/l (SD = 15.1) and 6.8 pmol/l (SD = 2.2) at baseline to 43.2 pmol/l (SD = 20.6) (p < 0.001) and 7.4 pmol/l (SD = 2.2) (p = 0.028), respectively. DKK-1 levels decreased from 34.3 pmol/l (SD = 13.5) at baseline to 29.7 pmol/l (SD = 12.3) at the 24-month visit (p = 0.005). Sclerostin levels significantly correlated with PTH, OPG and BMD of the lumbar spine, while DKK-1 correlated with the BMD of the femoral neck and of the total hip.

CONCLUSIONS

The observed increase in sclerostin levels indicates a central role of osteocytes in bone turnover in women with BC.

Differential regulation of estrogen receptors α and β by 4-(E)-{(4-hydroxyphenylimino)-methylbenzene,1,2-diol}, a novel resveratrol analog

Breast cancer is the second leading cause of death among women in the United States. Estrogens have been implicated as major risk factors in the development of breast neoplasms. Recent epidemiologic studies have suggested a protective role of phytoestrogens in prevention of breast and other cancers. Resveratrol, a naturally occurring phytoestrogen found notably in red grapes, berries and peanuts, has been shown to possess potent anti-cancer properties. However, the poor efficacy of resveratrol has prevented its use in a clinical setting. In order to improve the efficacy of resveratrol, we have synthesized a small combinatorial library of azaresveratrol analogs and tested them for their ability to inhibit the growth of breast cancer cell lines. We have recently shown that one of the synthesized analogs, 4-(E)-{(4-hydroxyphenylimino)-methylbenzene,1,2-diol} (HPIMBD), has better anti-cancer properties than resveratrol. The objective of this study was to investigate the differential regulation of estrogen receptors (ERs) α and β as a potential mechanism of inhibition of breast cancer by HPIMBD. Estrogen receptors α and β have been shown to have opposing roles in cellular proliferation. Estrogen receptor α mediates the proliferative responses of estrogens while ERβ plays an anti-proliferative and pro-apoptotic role. We demonstrate that HPIMBD significantly induces the expression of ERβ and inhibits the expression of ERα. HPIMBD also inhibits the protein expression levels of oncogene c-Myc and cell cycle protein cyclin D1, genes downstream to ERα and important regulators of cell cycle, and cellular proliferation. HPIMBD significantly induces protein expression levels of tumor suppressors p53 and p21 in MCF-7 cells. Additionally, HPIMBD inhibits c-Myc in an ERβ-dependent fashion in MCF-10A and ERβ1-transfected MDA-MB-231 cells, suggesting regulation of ERs as an important upstream mechanism of this novel compound. Molecular docking studies confirm higher affinity for binding of HPIMBD in the ERβ cavity. Thus, HPIMBD, a novel azaresveratrol analog may inhibit the proliferation of breast cancer cells by differentially modulating the expressions of ERs α and β.

The pyrido[b]indole MDM2 inhibitor SP-141 exerts potent therapeutic effects in breast cancer models

A requirement for Mouse Double Minute 2 (MDM2) oncogene activation has been suggested to be associated with cancer progression and metastasis, including breast cancer. To date, most MDM2 inhibitors have been designed to block the MDM2-p53-binding interphase, and have low or no efficacy against advanced breast cancer with mutant or deficient p53. Here we use a high-throughput screening and computer-aided, structure-based rational drug design, and identify a lead compound, SP-141, which can directly bind to MDM2, inhibit MDM2 expression and induce its autoubiquitination and proteasomal degradation. SP-141 has strong in vitro and in vivo antibreast cancer activity, with no apparent host toxicity. While further investigation is needed, our data indicate that SP-141 is a novel targeted therapeutic agent that may especially benefit patients with advanced disease.

MicroRNA-185 inhibits proliferation by targeting c-Met in human breast cancer cells

MicroRNAs (miRNAs) are a group of small non-coding RNA molecules that have been shown to regulate the expression of genes involved in tumorigenesis. The relevance of miRNAs in the development, progression and prognosis of human breast cancer is not fully understood. miR-185 has been demonstrated to be involved in the pathogenesis of several types of cancers; however, its role in breast cancer has not yet been elucidated. In the present study, the expression of miR-185 was analyzed by quantitative polymerase chain reaction. In addition, an MTT assay and flow cytometry were used to determine the rates of cell proliferation and apoptosis. Protein expression was analyzed by western blotting and the target gene was confirmed using a luciferase reporter assay. The expression of miR-185 was found to be downregulated in the breast cancer tissues. The MTT assay revealed that overexpression of miR-185 inhibited the proliferation of MDF7 and SKBR3 cells. Furthermore, flow cytometric analysis demonstrated that increased expression levels of miR-185 promoted the apoptosis of breast cancer cells. In addition, c-Met expression was demonstrated to be significantly upregulated in breast cancer tissues and cells, and the c-Met gene was identified to be a target of miR-185. Therefore, the results demonstrated that miR-185 inhibited the proliferation of breast cancer cells by regulating the expression of c-Met, indicating its potential as a therapeutic target for breast cancer.

Breast cancer in young women: special considerations in multidisciplinary care

Breast cancer is one of the most prevalent cancers in females, and 5%-7% of breast cancer cases occur in women under 40 years of age. Breast cancer in the young has gained increased attention with an attempt to improve diagnosis and prognosis. Young patients tend to have different epidemiology, presenting with later stages and more aggressive phenotypes. Diagnostic imaging is also more difficult in this age group. Multidisciplinary care generally encompasses surgeons, medical oncologists, radiation oncologists, radiologists, and social workers. Other special considerations include reconstruction options, fertility, genetics, and psychosocial issues. These concerns enlarge the already diverse multidisciplinary team to incorporate new expertise, such as reproductive specialists and genetic counselors. This review encompasses an overview of the current multimodal treatment regimens and the unique challenges in treating this special population. Integration of diagnosis, treatment, and quality of life issues should be addressed and understood by each member in the interdisciplinary team in order to optimize outcomes.

Prognostic value of preoperative inflammatory markers in Chinese patients with breast cancer

Cancer-associated inflammation is a key determinant of disease progression and survival in most cancers. The aim of our study was to assess the predictive value of preoperative inflammatory markers, such as the neutrophil–lymphocyte ratio (NLR), platelet–lymphocyte ratio, red cell distribution width (RDW), and mean platelet volume, for survival in breast cancer patients. In total, 608 breast cancer patients operated on between January 2009 and December 2011 were included in this observational study. The association between preoperative inflammatory markers and survival outcomes was analyzed. Patients with high NLR (>2.57) or high RDW (>13.45%) showed a significantly lower overall survival rate than those with lower NLR (≤2.57) or lower RDW (≤13.45%). NLR and RDW, along with node stage and molecular subtypes, were independent prognostic factors. There was a significant survival difference according to NLR in the luminal A and triple-negative subtypes (93.3% versus 99.3%, P=0.001; 68.8% versus 95.1%, P=0.000, respectively). The triple-negative subtype was the only subtype in which higher RDW patients showed significantly poor prognosis (81.3% versus 95.5%, P=0.025). Pre-operation NLR and RDW is a convenient, easily measured prognostic indicator for patients with breast cancer, especially in patients with the triple-negative subtype.

Ubiquitin-conjugating enzyme Ubc13 controls breast cancer metastasis through a TAK1-p38 MAP kinase cascade

Metastatic spread is the leading cause of cancer mortality. Breast cancer (BCa) metastatic recurrence can happen years after removal of the primary tumor. Here we show that Ubc13, an E2 enzyme that catalyzes K63-linked protein polyubiquitination, is largely dispensable for primary mammary tumor growth but is required for metastatic spread and lung colonization by BCa cells. Loss of Ubc13 inhibited BCa growth and survival only at metastatic sites. Ubc13 was dispensable for transforming growth factor β (TGFβ)-induced SMAD activation but was required for activation of non-SMAD signaling via TGFβ-activating kinase 1 (TAK1) and p38, whose activity controls expression of numerous metastasis promoting genes. p38 activation restored metastatic activity to Ubc13-deficient cells, and its pharmacological inhibition attenuated BCa metastasis in mice, suggesting it is a therapeutic option for metastatic BCa.

Transferrin-bound proteins as potential biomarkers for advanced breast cancer patients

Background

Serum profiling using mass spectrometry-based proteomic techniques has great potential to detect biomarkers that might improve the management for advanced breast cancer patients. The albuminome has previously been investigated as a tool in biomarker discovery, however other high abundant blood proteins are also likely to sequester potentially interesting molecules.

Methods

Affinity resin purified and isolated Transferrin and associated bound proteins from normal control and breast cancer patient serum samples were analysed by label-free mass spectrometry during the discovery phase.

Results

21 significant proteins were identified with Fibrinogen and Fibronectin selected for further analysis in an independent sample set, with significant difference found when comparing the controls groups (normal healthy control, inflammatory bowel disease and benign breast disease) to stage IV breast cancer.

Conclusions

The area under the curve value for Fibrinogen compared favourably with cancer antigen 15-3, an established breast cancer tumour marker. A combination of all three biomarkers improved accuracy when comparing control/benign to stage IV breast cancer patient groups.

General significance

Mass spectrometry profiling of Transferrin-bound proteins has revealed serum proteins that can distinguish between serum from advanced breast cancer patients and healthy control subjects with high confidence.

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Transferrin was found to interact with many candidate biomarkers.

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21 significant proteins were identified bound to Transferrin.

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Many of these proteins are associated with the complement and coagulations systems.

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Fibrinogen and Fibronectin were found to have significant AUC values.

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High abundant proteins harbour potential diagnostic molecules.

Molecular breast cancer subtypes and therapies in a public hospital of northeastern Brazil

BACKGROUND

The frequencies of molecular breast cancer subtypes vary among different human populations. The Northeastern region of Brazil has a mixed population of African, Indigenous and European ancestry. This retrospective study investigated breast cancer subtypes and applied therapies in a public hospital of Northeastern Brazil.

METHODS

Data of 633 patients with invasive breast cancer from 2005 to 2011 were obtained from medical records. Status of hormone receptor (HR), HER2 and Ki67 expression index of 269 out of 633 patients were used to define subtypes of Luminal A and B, HER2 and triple negative (TN) breast cancer. Expression index of Ki67 ≥ 14% was applied to distinguish Luminal A from Luminal B subtypes.

RESULTS

Overall, 185 (68.77%) and 132 (49.07%) patients showed positive hormone receptor (HR+) and positive HER2 (HER2+) tumors. The mean age ranged from 53.33 to 58.25 years for patients with tumors of Luminal B and Luminal A subtypes, respectively (p = 0.0182). In general, 67.39% of patients with TN tumors aged over 50 and 19.57% aged between 31 and 40 years (p = 0.0046). The rate of small tumors (T1: ≤ 2.0 cm) varied from 22.73% to 52.46% for TN and Luminal A subtypes (p = 0.0088). The rate of high graded (G3) tumors was increased for HER2 and TN subtypes (35.29% and 34.28%) compared to Luminal A and Luminal B subtypes (3.92% and 12.62%), respectively (p < 0.0001). The five-year survival rate ranged from 92.86% to 75.00%, for Luminal A, HER2 and TN subtypes, respectively (HR: 0.260 to 1.015; 95% CI: 0.043 to 3.594; p = 0.2589). Patients with HER2 positive (HER2+) breast tumors did not receive immunotherapy and chemotherapy application varied from 54.84% to 86.49% for Luminal A and HER2 subtypes, respectively (p = 0.0131).

CONCLUSIONS

The results of this study revealed a high percentage of HER2+ breast tumors and an increased rate of patients with TN tumors aged over 50 years. This emphasizes the need for establishing immunotherapy as an additional therapeutic option to improve clinical outcomes for patients with HER2+ tumors and to investigate the risk factors of TN breast cancer.

The efficacy of mammography boot camp to improve the performance of radiologists

Objective

To evaluate the efficacy of a mammography boot camp (MBC) to improve radiologists' performance in interpreting mammograms in the National Cancer Screening Program (NCSP) in Korea.

Materials and Methods

Between January and July of 2013, 141 radiologists were invited to a 3-day educational program composed of lectures and group practice readings using 250 digital mammography cases. The radiologists' performance in interpreting mammograms were evaluated using a pre- and post-camp test set of 25 cases validated prior to the camp by experienced breast radiologists. Factors affecting the radiologists' performance, including age, type of attending institution, and type of test set cases, were analyzed.

Results

The average scores of the pre- and post-camp tests were 56.0 ± 12.2 and 78.3 ± 9.2, respectively (p < 0.001). The post-camp test scores were higher than the pre-camp test scores for all age groups and all types of attending institutions (p < 0.001). The rate of incorrect answers in the post-camp test decreased compared to the pre-camp test for all suspicious cases, but not for negative cases (p > 0.05).

Conclusion

The MBC improves radiologists' performance in interpreting mammograms irrespective of age and type of attending institution. Improved interpretation is observed for suspicious cases, but not for negative cases.

Metabolomics in cell culture--a strategy to study crucial metabolic pathways in cancer development and the response to treatment

Metabolomics is a comprehensive tool for monitoring processes within biological systems. Thus, metabolomics may be widely applied to the determination of diagnostic biomarkers for certain diseases or treatment outcomes. There is significant potential for metabolomics to be implemented in cancer research because cancer may modify metabolic pathways in the whole organism. However, not all biological questions can be answered solely by the examination of small molecule composition in biofluids; in particular, the study of cellular processes or preclinical drug testing requires ex vivo models. The major objective of this review was to summarise the current achievement in the field of metabolomics in cancer cell culture-focusing on the metabolic pathways regulated in different cancer cell lines-and progress that has been made in the area of drug screening and development by the implementation of metabolomics in cell lines.

Therapeutic options for the management of pancreatic cancer

Since its initial characterization, pancreatic ductal adenocarcinoma has remained one of the most devastating and difficult cancers to treat. Pancreatic cancer is the fourth leading cause of death in the United States, resulting in an estimated 38460 deaths annually. With few screening tools available to detect this disease at an early stage, 94% of patients will die within five years of diagnosis. Despite decades of research that have led to a better understanding of the molecular and cellular signaling pathways in pancreatic cancer cells, few effective therapies have been developed to target these pathways. Other treatment options have included more sophisticated pancreatic cancer surgeries and combination therapies. While outcomes have improved modestly for these patients, more effective treatments are desperately needed. One of the greatest challenges in the future of treating this malignancy will be to develop therapies that target the tumor microenvironment and surrounding pancreatic cancer stem cells in addition to pancreatic cancer cells. Recent advances in targeting pancreatic stellate cells and the stroma have encouraged researchers to shift their focus to the role of desmoplasia in pancreatic cancer pathobiology in the hopes of developing newer-generation therapies. By combining novel agents with current cytotoxic chemotherapies and radiation therapy and personalizing them to each patient based on specific biomarkers, the goal of prolonging a patient’s life could be achieved. Here we review the most effective therapies that have been used for the treatment of pancreatic cancer and discuss the future potential of therapeutic options.

Association between the tumor necrosis factor alpha gene -308G> A polymorphism and the risk of breast cancer: a meta-analysis

The multifunctional cytokine tumor necrosis factor alpha (TNF-α) plays an important role in cell proliferation, differentiation, apoptosis, lipid metabolism, and endothelial function. To date, many studies have evaluated the association between the TNF-α -308G> A polymorphism and breast cancer risk; however, the results remain ambiguous and inconclusive. To derive a more precise estimation of the association and assess its strength, we carried out a meta-analysis of 20 published case-control studies with 12,360 cases and 15,110 controls using crude odd ratios (ORs) with 95 % confidence intervals (CIs). Overall, no significant associations were found for all genetic models (allele model OR = 1.06, 95 % CI 0.90-1.24, P heterogeneity < 0.001; homozygous model OR = 1.25, 95 % CI 0.85-1.82, P heterogeneity < 0.001; recessive model OR = 1.26, 95 % CI 0.88-1.82, P heterogeneity = 0.001; dominant model OR = 1.00, 95 % CI 0.85-1.18, P heterogeneity < 0.001). Moreover, no significant associations were observed when stratified by ethnicity, control source, genotyping method, or Hardy-Weinberg equilibrium status. However, in the menopausal status subgroup, significantly decreased breast cancer risks were found among postmenopausal women (allele model OR = 0.90, 95 % CI 0.83-0.98; dominant model OR = 0.89, 95 % CI 0.81-0.98), while the TNF-α -308 AA genotype was a breast cancer risk factor in premenopausal women (homozygous model OR = 4.38, 95 % CI 1.44-13.36; recessive model OR = 4.43, 95 % CI 1.47-13.42). This meta-analysis indicated that the TNF-α -308G> A polymorphism is not associated with breast cancer risk in the overall population but that the A allele may be a protective factor for breast cancer in postmenopausal women, and the AA genotype may be a breast cancer risk factor in premenopausal women.

CD109 is a potential target for triple-negative breast cancer

The aim of this study is to explore the expression of CD109 in breast cancer stem cells and the relationship between CD109 protein and clinicopathological characteristics of breast cancer. CD44+/CD24- tumor cells (CSCs) were selected by flow cytometry. The protein expression of CD109 was analyzed by immunohistochemistry staining, and the relationship between CD109 and clinicopathological parameters of breast cancer was determined. CD109 positively regulated the proliferation of breast CSCs in vitro, and CD109 protein expression was significantly higher in triple-negative breast cancer (TNBC) compared to non-TNBC (63.78 vs. 3.71 %, P = 0.001). Moreover, CD109 protein expression was related to the histological grade of breast cancer (P = 0.015), whereas age (P = 0.731), tumor size (P = 0.995), clinical stage (P = 0.644), and lymph node metastasis (P = 0.924) were not. In the logistic regression model, histological grade (P = 0.001) and molecular type (P = 0.001) were significantly related to CD109 expression. The patients with high expression of CD109 protein had significantly poorer postoperative disease-specific survival than those with no or low expression of CD109 protein (P = 0.001). In the Cox regression, CD109 was an independent prognostic factor (P = 0.001). CD109 is highly expressed in TNBC and is a potential biomarker for the initiation, progression, and differentiation of breast cancer tumors.

Effect of anastrozole on hormone levels in postmenopausal women with early breast cancer

OBJECTIVES

The aim of this study was to investigate the influence of anastrozole on serum hormone levels in postmenopausal women with hormone receptor-positive breast cancer.

METHODS

We prospectively determined serum levels of estradiol, testosterone, dehydroepiandrosterone sulfate (DHEAS), sex hormone binding globulin (SHBG), follicle stimulating hormone (FSH) and luteinizing hormone (LH) at screening, as well as after 12 and 24 months of treatment and studied the associations with markers of bone turnover and bone mineral density (BMD).

RESULTS

Altogether, a full set of hormone levels was available for 70 patients. Anastrozole treatment led to decreases of 92.1% for estradiol and 11.1% for LH over the observation period (p < 0.001). Conversely, FSH, DHEAS and testosterone concentrations increased by 5.9%, 33.3% and 50%, respectively (p < 0.001). SHBG levels remained stable during the 24 months of treatment (p = 0.355). There were modest associations between FSH, SHBG, CrossLaps and N-terminal propeptide of human procollagen type I (p < 0.05). Moreover, SHBG correlated positively with the BMD of femoral neck, total hip, total hip T-score, lumbar spine and the lumbar spine T-score, whereas FSH and estradiol correlated with the lumbar spine T-score (p < 0.05).

CONCLUSIONS

During the 24 months of follow-up, treatment with anastrozole decreased the serum levels of estradiol and LH. Furthermore, we found notable increases of serum levels of FSH, DHEAS and testosterone in the first 12 months of treatment, stabilizing thereafter. Additionally, we were able to correlate hormone levels with markers of bone turnover and BMD for the first time in this regard.

Estrogen receptor-α36 is involved in pterostilbene-induced apoptosis and anti-proliferation in in vitro and in vivo breast cancer

Pterostilbene (trans-3,5-dimethoxy-4′-hudroxystilbene) is an antioxidant primarily found in blueberries. It also inhibits breast cancer regardless of conventional estrogen receptor (ER-α66) status by inducing both caspase-dependent and caspase-independent apoptosis. However, the pterostilbene-induced apoptosis rate in ER-α66-negative breast cancer cells is much higher than that in ER-α66-positive breast cancer cells. ER-α36, a variant of ER-α66, is widely expressed in ER-α66-negative breast cancer, and its high expression mediates the resistance of ER-α66-positive breast cancer patients to tamoxifen therapy. The aim of the present study is to determine the relationship between the antiproliferation activity of pterostilbene and ER-α36 expression in breast cancer cells. Methyl-thiazolyl-tetrazolium (MTT) assay, apoptosis analysis, and an orthotropic xenograft mouse model were used to examine the effects of pterostilbene on breast cancer cells. The expressions of ER-α36 and caspase 3, the activation of ERK and Akt were also studied through RT-PCR, western blot analysis, and immunohistochemical (IHC) staining. ER-α36 knockdown was found to desensitize ER-α66-negative breast cancer cells to pterostilbene treatment both in vitro and in vivo, and high ER-α36 expression promotes pterostilbene-induced apoptosis in breast cancer cells. Western blot analysis data indicate that MAPK/ERK and PI3K/Akt signaling in breast cancer cells with high ER-α36 expression are mediated by ER-α36, and are inhibited by pterostilbene. These results suggest that ER-α36 is a therapeutic target in ER-α36-positive breast cancer, and pterostilbene is an inhibitor that targets ER-α36 in the personalized therapy against ER-α36-positive breast cancer.

Utility of GATA3 immunohistochemistry for diagnosis of metastatic breast carcinoma in cytology specimens

BACKGROUND

GATA3 as a diagnostic marker of metastatic breast carcinoma in cytology specimens has not been fully established.

METHODS

Metastatic breast carcinoma was assessed for GATA3, mammaglobin, and GCDFP-15 immunohistochemistry on cell blocks. GATA3 was scored by intensity (0, negative; 1, weakly positive; 2, moderately positive; 3, strongly positive), and area (0-100%). Mammaglobin (MMG) and GCDFP-15 staining was scored qualitatively (positive vs. negative). Results were correlated with specimen type (fine-needle aspiration vs. body fluid), breast prognostic markers estrogen receptor (ER), progesterone receptor (PR), Her-2/Neu (Her2), and Ki67, and with each other. Statistical significance was determined by chi-squared test and ANOVA for numerical variables. Alpha was set as 0.05. A total of 40 CB specimens containing metastatic breast carcinoma were studied.

RESULTS

GATA3 was positive in 32 (80%) cases. All ER-positive cases (n = 25) were positive for GATA3. Conversely, all GATA3-negative cases (n = 8) were triple-negative breast cancers. On qualitative univariate analysis, GATA3 was statistically associated with ER (P = 0.0001), and PR (P = 0.0468). GATA3 intensity was statistically associated with ER (P ≤ 0.0001), PR (P = 0.0157), Her2 (P = 0.0256), and cancer category (P = 0.0127). GATA3 staining was statistically associated with ER (P ≤ 0.0001), PR (P = 0.0160), Her2 (P = 0.0451), and cancer category (P = 0.0002). MMG and GCDFP-15 were directly compared to GATA3 in 35 samples. The sensitivity was 86% for GATA3, 26% for MMG, and 14% for GCDFP-15.

CONCLUSION

GATA3 is a more sensitive diagnostic marker of metastatic breast carcinoma in CB samples than MMG and GCDFP-15.

Identification and validation of genes with expression patterns inverse to multiple metastasis suppressor genes in breast cancer cell lines

Metastasis suppressor genes (MSGs) have contributed to an understanding of regulatory pathways unique to the lethal metastatic process. When re-expressed in experimental models, MSGs block cancer spread to, and colonization of distant sites without affecting primary tumor formation. Genes have been identified with expression patterns inverse to a single MSG, and found to encode functional, druggable signaling pathways. We now hypothesize that common signaling pathways mediate the effects of multiple MSGs. By gene expression profiling of human MCF7 breast carcinoma cells expressing a scrambled siRNA, or siRNAs to each of 19 validated MSGs (NME1, BRMS1, CD82, CDH1, CDH2, CDH11, CASP8, MAP2K4, MAP2K6, MAP2K7, MAPK14, GSN, ARHGDIB, AKAP12, DRG1, CD44, PEBP1, RRM1, KISS1), we identified genes whose expression was significantly opposite to at least five MSGs. Five genes were selected for further analysis: PDE5A, UGT1A, IL11RA, DNM3 and OAS1. After stable downregulation of each candidate gene in the aggressive human breast cancer cell line MDA-MB-231T, in vitro motility was significantly inhibited. Two stable clones downregulating PDE5A (phosphodiesterase 5A), an enzyme involved in the regulation of cGMP-specific signaling, exhibited no difference in cell proliferation, but reduced motility by 47 and 66 % compared to the empty vector-expressing cells (p = 0.01 and p = 0.005). In an experimental metastasis assay, two shPDE5A-MDA-MB-231T clones produced 47-62 % fewer lung metastases than shRNA-scramble expressing cells (p = 0.045 and p = 0.009 respectively). This study demonstrates that previously unrecognized genes are inversely related to the expression of multiple MSGs, contribute to aspects of metastasis, and may stand as novel therapeutic targets.

Use of the comet assay technique for quick and reliable prediction of in vitro response to chemotherapeutics in breast and colon cancer

Background

Determination of response to chemotherapy is a major requirement of personalized medicine. Resistance, whether developed or native, critically affects a treatment’s success. Single Cell Gel lectrophoresis - also known as a comet assay - is used to detect DNA damage at the level of individual eukaryotic cells. We assessed the use of comet assays in determining response to chemotherapeutic drugs that are widely used in breast and colon cancer.

Results

We treated human breast and colon cancer cell lines with melphalan, cisplatin, mechlorethamine or doxorubicin, as monotherapies. Drug activities varied even in the same cancer types, further demonstrating the heterogeneity of different cancer types.

Conclusion

The comet assay technique can provide reliable and quick results with minimum requirements and is applicable to a wide variety of drugs.

How many etiological subtypes of breast cancer: two, three, four, or more?

Breast cancer is a heterogeneous disease, divisible into a variable number of clinical subtypes. A fundamental question is how many etiological classes underlie the clinical spectrum of breast cancer? An etiological subtype reflects a grouping with a common set of causes, whereas a clinical subtype represents a grouping with similar prognosis and/or prediction. Herein, we review the evidence for breast cancer etiological heterogeneity. We then evaluate the etiological evidence with mRNA profiling data. A bimodal age distribution at diagnosis with peak frequencies near ages 50 and 70 years is a fundamental characteristic of breast cancer for important tumor features, clinical characteristics, risk factor profiles, and molecular subtypes. The bimodal peak frequencies at diagnosis divide breast cancer overall into a "mixture" of two main components in varying proportions in different cancer populations. The first breast cancer tends to arise early in life with modal age-at-diagnosis near 50 years and generally behaves aggressively. The second breast cancer occurs later in life with modal age near 70 years and usually portends a more indolent clinical course. These epidemiological and molecular data are consistent with a two-component mixture model and compatible with a hierarchal view of breast cancers arising from two main cell types of origin. Notwithstanding the potential added value of more detailed categorizations for personalized breast cancer treatment, we suggest that the development of better criteria to identify the two proposed etiologic classes would advance breast cancer research and prevention.

MicroRNA-495 induces breast cancer cell migration by targeting JAM-A

MicroRNAs (miRNAs) are small, non-coding RNAs that function as post-transcriptional regulators of gene expression. The deregulated expression of miRNAs is associated with a variety of diseases, including breast cancer. In the present study, we found that miR-495 was markedly up-regulated in clinical breast cancer samples by quantitative real time-PCR (qRT-PCR). Junctional adhesion molecule A (JAM-A) was predicted to be a potential target of miR-495 by bioinformatics analysis and was subsequently verified by luciferase assay and Western blotting. JAM-A was found to be negatively correlated with the migration of breast cancer cells through loss-of-function and gain-of-function assays, and the inhibition of JAM-A by miR-495 promoted the migration of MCF-7 and MDA-MB-231 cells. Furthermore, overexpression of JAM-A could restore miR-495-induced breast cancer cell migration. Taken together, our findings suggest that miR-495 could facilitate breast cancer progression through the repression of JAM-A, making this miRNA a potential therapeutic target.

Overexpressed ubiquitin ligase Cullin7 in breast cancer promotes cell proliferation and invasion via down-regulating p53

Ubiquitin ligase Cullin7 has been identified as an oncogene in some malignant diseases such as choriocarcinoma and neuroblastoma. However, the role of Cullin7 in breast cancer carcinogenesis remains unclear. In this study, we compared Cullin7 protein levels in breast cancer tissues with normal breast tissues and identified significantly higher expression of Cullin7 protein in breast cancer specimens. By overexpressing Cullin7 in breast cancer cells HCC1937, we found that Cullin7 could promote cell growth and invasion in vitro. In contrast, the cell growth and invasion was inhibited by silencing Cullin7 in breast cancer cell BT474. Moreover, we demonstrated that Cullin7 promoted breast cancer cell proliferation and invasion via down-regulating p53 expression. Thus, our study provided evidence that Cullin7 functions as a novel oncogene in breast cancer and may be a potential therapeutic target for breast cancer management.

Psychosocial factors in adjuvant hormone therapy for breast cancer: an emerging context for adherence research

PURPOSE

For patients with hormone receptor positive breast cancer, survivorship entails prolonged self-management of adjuvant treatment in the form of daily hormone therapy. Although sustained daily adherence across the 5-year course of therapy is associated with improved recurrence-free survival outcomes, adherence is suboptimal and many women discontinue hormone therapy prematurely. Factors associated with breast cancer survivors' nonadherence and nonpersistence are not comprehensively understood. Furthermore, psychosocial variables have only received limited research attention, despite their documented relationships with adherence in other chronic illness populations.

METHODS

A systematic literature review identified 14 studies that analyzed relationships between psychosocial factors and breast cancer survivors' adherence and/or persistence with adjuvant hormone therapy.

RESULTS

Although identified relationships were complex and at times inconsistent, salient conclusions emerged. Interpersonal factors, in the form of positive social support and patient-centered interactions with medical providers, as well as intrapersonal factors, such as anxiety and beliefs about the relative benefits of medication use, were reliably associated with better adherence and persistence. Depression did not demonstrate the negative impact on adherence that has been observed in other medical populations. No relationships between quality of life and adherence were identified.

CONCLUSIONS

Adjuvant hormone therapy appears to be a unique context for medication adherence, which warrants further attention and more rigorous analysis in future research.

IMPLICATIONS FOR CANCER SURVIVORS

Individual patients' psychosocial characteristics and health care preferences should be considered when striving to optimize medication adherence.

Perceptions of and preferences for federally-funded family planning clinics

BACKGROUND

The Title X family planning program provides affordable access to a range of sexual and reproductive health services, with a priority for low-income people. The disproportionate burden of unintended pregnancy, breast and cervical cancer, and sexually transmitted diseases among minority groups, teens, and young adults in the US underscore the need for affordable access to such services. However, increased access to sexual and reproductive health services, resulting from the Affordable Care Act (ACA) create questions regarding the continued need for this program.

METHODS

A study was conducted to assess clients' perceptions of Title X-funded family planning clinics and their preferences for these clinics for a range of sexual and reproductive health services. An anonymous, self-administered, paper-and-pencil survey was administered to 696 clients who received services from one of eight Title X-funded family planning clinics in Northeast Ohio.

RESULTS

The majority of participants stated very positive perceptions of the Title X-funded clinics; that they "Always" go to the Title X-funded clinic for birth control, STD/HIV testing, and pregnancy testing; and that the Title X-funded clinic was their regular source of health care. Females were more likely than males to prefer the Title X clinic for birth control, physical exams, pregnancy testing, and health information and more teens under the age of 18 preferred to use the Title X clinic for STD/HIV testing, physical exams, pregnancy testing, and health information.

CONCLUSIONS

Findings indicate that these Title X-funded family planning clinics successfully reached populations in need of sexual and reproductive health services and suggest that these facilities can help play an important role in reducing disparities even after full implementation of the Affordable Care Act. However, more research is needed to fully quantify the need and value of Title X-funded family planning clinics and its relation to the changing health care environment in the US.

Tamoxifen co-administration during controlled ovarian hyperstimulation for in vitro fertilization in breast cancer patients increases the safety of fertility-preservation treatment strategies

OBJECTIVE

To evaluate the safety and efficacy of tamoxifen co-administration during conventional controlled ovarian hyperstimulation (COH) protocols for a fertility-preservation IVF cycle in breast cancer patients.

DESIGN

Two groups: retrospective descriptive cohort study and prospective study.

SETTING

Breast cancer oncology and fertility-preservation centers in a tertiary hospital.

PATIENT(S)

Two groups of breast cancer patients: premenopausal patients treated with adjuvant tamoxifen; and patients undergoing in vitro fertilization (IVF) for fertility preservation.

INTERVENTION(S)

Fertility-preservation cycles, tamoxifen co-administration during conventional IVF.

MAIN OUTCOME MEASURE(S)

Endocrine records, and IVF results.

RESULT(S)

Estradiol (E2) levels were chronically high (mean 2663 pmol/L, maximum: 10,000 pmol/L) in 38 of 46 breast cancer patients treated with adjuvant tamoxifen. Co-administration of tamoxifen (48 cycles) during conventional IVF or without tamoxifen (26 cycles), using either the long gonadotropin-releasing hormone-agonist or-antagonist protocols, resulted, respectively, in a mean of 12.65 and 10.2 oocytes retrieved, and 8.5 and 6.4 embryos cryopreserved. Average peak E2 levels were 6,924 pmol/L and 5,093 pmol/L, respectively, but long-term recurrence risk (up to 10 years) was not increased.

CONCLUSION(S)

In breast cancer patients, co-administration of tamoxifen during conventional COH for fertility preservation does not interfere with IVF results. The high serum E2 levels during COH should be considered safe, as it simulates the high prevalence of persistently high serum E2 levels in premenopausal breast cancer patients safely treated with adjuvant tamoxifen.

Gemcitabine resistance in breast cancer cells regulated by PI3K/AKT-mediated cellular proliferation exerts negative feedback via the MEK/MAPK and mTOR pathways

Chemoresistance is a major cause of cancer treatment failure and leads to a reduction in the survival rate of cancer patients. Phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) and mitogen-activated protein kinase (MAPK) pathways are aberrantly activated in many malignant tumors, including breast cancer, which may indicate an association with breast cancer chemoresistance. In this study, we generated a chemoresistant human breast cancer cell line, MDA-MB-231/gemcitabine (simplified hereafter as "231/Gem"), from MDA-MB-231 human breast cancer cells. Flow cytometry studies revealed that with the same treatment concentration of gemcitabine, 231/Gem cells displayed more robust resistance to gemcitabine, which was reflected by fewer apoptotic cells and enhanced percentage of S-phase cells. Through the use of inverted microscopy, Cell Counting Kit-8, and Transwell assays, we found that compared with parental 231 cells, 231/Gem cells displayed more morphologic projections, enhanced cell proliferative ability, and improved cell migration and invasion. Mechanistic studies revealed that the PI3K/AKT/mTOR and mitogen-activated protein kinase kinase (MEK)/MAPK signaling pathways were activated through elevated expression of phosphorylated (p)-extracellular signal-regulated kinase (ERK), p-AKT, mTOR, p-mTOR, p-P70S6K, and reduced expression of p-P38 and LC3-II (the marker of autophagy) in 231/Gem in comparison to control cells. However, there was no change in the expression of Cyclin D1 and p-adenosine monophosphate-activated protein kinase (AMPK). In culture, inhibitors of PI3K/AKT and mTOR, but not of MEK/MAPK, could reverse the enhanced proliferative ability of 231/Gem cells. Western blot analysis showed that treatment with a PI3K/AKT inhibitor decreased the expression levels of p-AKT, p-MEK, p-mTOR, and p-P70S6K; however, treatments with either MEK/MAPK or mTOR inhibitor significantly increased p-AKT expression. Thus, our data suggest that gemcitabine resistance in breast cancer cells is mainly mediated by activation of the PI3K/AKT signaling pathway. This occurs through elevated expression of p-AKT protein to promote cell proliferation and is negatively regulated by the MEK/MAPK and mTOR pathways.

HITS-CLIP reveals key regulators of nuclear receptor signaling in breast cancer

miRNAs regulate the expression of genes in both normal physiology and disease. While miRNAs have been demonstrated to play a pivotal role in aspects of cancer biology, these reports have generally focused on the regulation of single genes. Such single-gene approaches have significant limitations, relying on miRNA expression levels and heuristic predictions of mRNA-binding sites. This results in only circumstantial evidence of miRNA-target interaction and typically leads to large numbers of false positive predictions. Here, we used a genome-wide approach (high-throughput sequencing of RNA isolated by crosslinking immunoprecipitation, HITS-CLIP) to define direct miRNA-mRNA interactions in three breast cancer subtypes (estrogen receptor positive, Her2 amplified, and triple negative). Focusing on steroid receptor signaling, we identified two novel regulators of the ER pathway (miR-9-5p and miR-193a/b-3p), which together target multiple genes involved in ER signaling. Moreover, this approach enabled the definition of miR-9-5p as a global regulator of steroid receptor signaling in breast cancer. We show that miRNA targets and networks defined by HITS-CLIP under physiologic conditions are predictive of patient outcomes and provide global insight into miRNA regulation in breast cancer.

One-pot synthesis of cinnamylideneacetophenones and their in vitro cytotoxicity in breast cancer cells

A series of cinnamylideneacetophenones were synthesized via a modified Claisen-Schmidt condensation reaction and evaluated for cytotoxicity against breast cancer cells using the Alamar Blue™ assay. Derivatives 17 and 18 bearing a 2-nitro group on the B ring, exhibited sub-micromolar cytotoxicity in MCF-7 cells (IC50=71 and 1.9 nM), respectively. Derivative 17 also displayed sub-micromolar (IC50=780 nM) cytotoxicity in MDA-MB-468 cells. Additionally, 17 and 18 displayed significantly less cytotoxicity than the chemotherapeutic doxorubicin in non-tumorigenic MCF-10A cells. This study provides evidence supporting the continued development of nitro-substituted cinnamylideneacetophenones as small molecules to treat breast cancer.

Resveratrol inhibits estrogen-induced breast carcinogenesis through induction of NRF2-mediated protective pathways

The importance of estrogens in the etiology of breast cancer is widely recognized. Estrogen-induced oxidative stress has been implicated in this carcinogenic process. Resveratrol (Res), a natural antioxidant phytoestrogen has chemopreventive effects against a variety of illnesses including cancer. The objective of the present study was to characterize the mechanism(s) of Res-mediated protection against estrogen-induced breast carcinogenesis. Female August Copenhagen Irish rats were treated with 17β-estradiol (E2), Res and Res + E2 for 8 months. Cotreatment of rats with Res and E2 inhibited E2-mediated proliferative changes in mammary tissues and significantly increased tumor latency and reduced E2-induced breast tumor development. Resveratrol treatment alone or in combination with E2 significantly upregulated expression of nuclear factor erythroid 2-related factor 2 (NRF2) in mammary tissues. Expression of NRF2-regulated antioxidant genes NQO1, SOD3 and OGG1 that are involved in protection against oxidative DNA damage was increased in Res- and Res + E2-treated mammary tissues. Resveratrol also prevented E2-mediated inhibition of detoxification genes AOX1 and FMO1. Inhibition of E2-mediated alterations in NRF2 promoter methylation and expression of NRF2 targeting miR-93 after Res treatment indicated Res-mediated epigenetic regulation of NRF2 during E2-induced breast carcinogenesis. Resveratrol treatment also induced apoptosis and inhibited E2-mediated increase in DNA damage in mammary tissues. Increased apoptosis and decreased DNA damage, cell migration, colony and mammosphere formation in Res- and Res + E2-treated MCF-10A cells suggested a protective role of Res against E2-induced mammary carcinogenesis. Small-interfering RNA-mediated silencing of NRF2 inhibited Res-mediated preventive effects on the colony and mammosphere formation. Taken together, these results suggest that Res inhibits E2-induced breast carcinogenesis via induction of NRF2-mediated protective pathways.

The mTOR inhibitor rapamycin synergizes with a fatty acid synthase inhibitor to induce cytotoxicity in ER/HER2-positive breast cancer cells

Patients with ER/HER2-positive breast cancer have a poor prognosis and are less responsive to selective estrogen receptor modulators; this is presumably due to the crosstalk between ER and HER2. Fatty acid synthase (FASN) is essential for the survival and maintenance of the malignant phenotype of breast cancer cells. An intimate relationship exists between FASN, ER and HER2. We hypothesized that FASN may be the downstream effector underlying ER/HER2 crosstalk through the PI3K/AKT/mTOR pathway in ER/HER2-positive breast cancer. The present study implicated the PI3K/AKT/mTOR pathway in the regulation of FASN expression in ER/HER2-positive breast cancer cells and demonstrated that rapamycin, an mTOR inhibitor, inhibited FASN expression. Cerulenin, a FASN inhibitor, synergized with rapamycin to induce apoptosis and inhibit cell migration and tumorigenesis in ER/HER2-positive breast cancer cells. Our findings suggest that inhibiting the mTOR-FASN axis is a promising new strategy for treating ER/HER2-positive breast cancer.

Different miRNA expression profiles between human breast cancer tumors and serum

A bunch of microRNAs (miRNAs) have been demonstrated to be aberrantly expressed in cancer tumor tissue and serum. The miRNA signatures identified from the serum samples could serve as potential noninvasive diagnostic markers for breast cancer. The role of the miRNAs in cancerigenesis is unclear. In this study, we generated the expression profiles of miRNAs from the paired breast cancer tumors, normal, tissue, and serum samples from eight patients using small RNA-sequencing. Serum samples from eight healthy individuals were used as normal controls. We identified total 174 significantly differentially expressed miRNAs between tumors and the normal tissues, and 109 miRNAs between serum from patients and serum from healthy individuals. There are only 10 common miRNAs. This suggests that only a small portion of tumor miRNAs are released into serum selectively. Interestingly, the expression change pattern of 28 miRNAs is opposite between breast cancer tumors and serum. Functional analysis shows that the differentially expressed miRNAs and their target genes form a complex interaction network affecting many biological processes and involving in many types of cancer such as prostate cancer, basal cell carcinoma, acute myeloid leukemia, and more.

Increased circulating microRNA-155 as a potential biomarker for breast cancer screening: a meta-analysis

The objective of this meta-analysis was to determine the diagnostic accuracy of circulating microRNA-155 (miR-155) for breast cancer (BC). PubMed, Embase, EBSCO (ASP/BSP), Cochrane Library and China National Knowledge Infrastructure (CNKI) were searched up to 30 January 2014 for eligible studies. Quality Assessment of Diagnostic Accuracy Studies (QUADAS) was employed to assess the quality of the included studies. Meta-analysis were performed in Meta-Disc 1.4 and Stata 12.0. Three studies with total 184 BC patients and 75 control individuals were included in this meta-analysis. All of the included studies are of high quality (QUADAS scores 12 or 13). The summary estimates revealed that the pooled sensitivity is 79% (95% confidence interval (CI): 72%–84%) and the specificity is 85% (95% CI: 75%–92%), for the diagnosis of breast cancer. In addition, the area under the summary ROC curve (AUC) is 0.9217. The current evidence suggests that circulating miR-155 has the potential diagnostic value with a high sensitivity and specificity for BC. More prospective studies on the diagnostic value of circulating miR-155 for BC are needed in the future.

Chitosan-based thermoreversible hydrogel as an in vitro tumor microenvironment for testing breast cancer therapies

Breast cancer is a major health problem for women worldwide. Although in vitro culture of established breast cancer cell lines is the most widely used model for preclinical assessment, it poorly represents the behavior of breast cancers in vivo. Acceleration of the development of effective therapeutic strategies requires a cost-efficient in vitro model that can more accurately resemble the in vivo tumor microenvironment. Here, we report the use of a thermoreversible poly(ethylene glycol)-g-chitosan hydrogel (PCgel) as an in vitro breast cancer model. We hypothesized that PCgel could provide a tumor microenvironment that promotes cultured cancer cells to a more malignant phenotype with drug and immune resistance. Traditional tissue culture plates and Matrigel were applied as controls in our studies. In vitro cellular proliferation and morphology, the secretion of angiogenesis-related growth factors and cytokines, and drug and immune resistance were assessed. Our results show that PCgel cultures promoted tumor aggregate formation, increased secretion of various angiogenesis- and metastasis-related growth factors and cytokines, and increased tumor cell resistance to chemotherapeutic drugs and immunotherapeutic T cells. This PCgel platform may offer a valuable strategy to bridge the gap between standard in vitro and costly animal studies for a wide variety of experimental designs.