Biomolecular prognostic factors in breast cancer

Ligand conjugated lipid-based nanocarriers for cancer theranostics

Cancer is one of the major health-related issues affecting the population worldwide and subsequently accounts for the second-largest death. Genetic and epigenetic modifications in oncogenes or tumor suppressor genes affect the regulatory systems that lead to the initiation and progression of cancer. Conventional methods, including chemotherapy/radiotherapy/appropriate combinational therapy and surgery, are being widely used for theranostics of cancer patients. Surgery is useful in treating localized tumors, but it is ineffective in treating metastatic tumors, which spread to other organs and result in a high recurrence rate and death. Also, the therapeutic application of free drugs is related to substantial issues such as poor absorption, solubility, bioavailability, high degradation rate, short shelf-life, and low therapeutic index. Therefore, these issues can be sorted out using nano lipid-based carriers (NLBCs) as promising drug delivery carriers. Still, at most, they fail to achieve site targeted drug delivery and detection. This can be achieved by selecting a specific ligand/antibody for its cognate receptor molecule expressed on the surface of cancer cell. In this review, we have mainly discussed the various types of ligands used to decorate NLBCs. A list of the ligands used to design nanocarriers to target malignant cells has been extensively undertaken. The approved ligand decorated lipid-based nanomedicines with their clinical status has been explained in tabulated form to provide a wider scope to the readers regarding ligand coupled NLBCs. This article is protected by copyright. All rights reserved.

Ligand decorated biodegradable nanomedicine in the treatment of cancer

Cancer is one of the major global health problems, responsible for the second-highest number of deaths. The genetic and epigenetic changes in the oncogenes or tumor suppressor genes alter the regulatory pathways leading to its onset and progression. Conventional methods are used in appropriate combinations for the treatment. Surgery effectively treats localized tumors; however, it fails to treat metastatic tumors, leading to a spread in other organs, causing a high recurrence rate and death. Among the different strategies, the nanocarriers-based approach is highly sought for, but its nonspecific delivery can cause a profound side effect on healthy cells. Targeted nanomedicine has the advantage of targeting cancer cells specifically by interacting with the receptors overexpressed on their surface, overcoming its non-specificity to target healthy cells. Nanocarriers prepared from biodegradable and biocompatible materials are decorated with different ligands by encapsulating therapeutic or diagnostic agents or both to target cancer cells overexpressing the receptors. Scientists are now utilizing a theranostic approach to simultaneously evaluate nanocarrier bio-distribution and its effect on the treatment regime. Herein, we have summarized the recent 5-year efforts in the development of the ligands decorated biodegradable nanocarriers, as a targeted nanomedicine approach, which has been highly promising in the treatment of cancer.

Matricellular proteins in drug delivery: Therapeutic targets, active agents, and therapeutic localization

Extracellular matrix is composed of a complex array of molecules that together provide structural and functional support to cells. These properties are mainly mediated by the activity of collagenous and elastic fibers, proteoglycans, and proteins such as fibronectin and laminin. ECM composition is tissue-specific and could include matricellular proteins whose primary role is to modulate cell-matrix interactions. In adults, matricellular proteins are primarily expressed during injury, inflammation and disease. Particularly, they are closely associated with the progression and prognosis of cardiovascular and fibrotic diseases, and cancer. This review aims to provide an overview of the potential use of matricellular proteins in drug delivery including the generation of therapeutic agents based on the properties and structures of these proteins as well as their utility as biomarkers for specific diseases.

p53 expression in pleomorphic adenoma of salivary glands: A systematic review and meta-analysis

OBJECTIVE

There are conflicting data regarding immunohistochemical expression of p53 in pleomorphic adenoma. This systematic review and meta-analysis aimed to examine whether p53 expression has a role in the pathogenesis of pleomorphic adenoma.

DESIGN

A comprehensive literature search for relevant studies published from 2000 up to end of 2014 was performed using PubMed, EMBASE and the Cochrane Library Databases. Only articles in which p53 detected by immunohistochemical staining were included. The meta-analysis was done using Comprehensive Meta-Analysis software.

RESULTS

Eighteen eligible studies were included in this meta-analysis. Heterogeneity measures showed a statistically significant Cochrane Q value (P-value<0.001). The random effects model showed an effect size of 0.254 with a 95% CI (0.139-0.417). The overall p53 positivity is 25.4%.

CONCLUSION

Mutant p53 has to be detected by more precise techniques to emphasize on its role in development of pleomorphic adenoma of salivary gland.

Genetic Instability and Disease Prognostication

Genetic instability is a striking feature of human cancers, with an impact on the genesis, progression and prognosis. The clinical importance of genomic instability and aneuploidy is underscored by its association with poor patient outcome in multiple cancer types, including breast and colon cancer. Interestingly, there is growing evidence that prognostic gene expression signatures simply reflect the degree of genomic instability. Additionally, also the proteome is affected by aneuploidy and has therefore become a powerful tool to screen for new targets for therapy, diagnosis and prognostication. In this context, the chapter presents the impact of genomic instability on disease prognostication occurring in human cancers.

Immunohistochemical study of apoptotic marker p53 as a prognostic factor in breast cancer

Histological study of breast cancer specimens obtained from 294 female residents in the Republic of Sakha (Yakutia) of different age and ethnic groups and immunohistochemical analysis of protein expression of mutant suppressor gene p53 in tumor cells were performed. A positive correlation was found between expression of mutant gene p53 protein and the degree of malignancy of breast tumors. The indicator should be considered when assessing malignancy potential and risk of breast cancer, because it is important for optimization and individualization of the treatment.

The expression and clinical significance of HERC4 in breast cancer

Background

Increasing evidence suggest that ubiquitin-proteasome system (UPS) plays a key role in tumorigenesis. HERC4 is a recently identified ubiqutin ligase. However, the expression status and biological functions of HERC4 in cancers are not clearly.

Methods

We evaluated the HERC4 expression in breast cancer cell lines and breast tumor tissues by quantitative real-time PCR and western blot analysis. To investigate the clinicopathological significance of HERC4, immunohistochemistry analysis for HERC4 was performed on a tissue microarray including 13 benign fibroadenoma, 15 intraductal carcinoma, 120 histologically confirmed invasive ductal carcinoma. Receiver operating characteristic (ROC) analysis was applied to determine the optimal cut-off score for positive expression of HERC4, when HERC4 positive expression percentage was above 60%, tumor was defined as “positive”.

Results

HERC4 was up-regulated in breast cancer cell lines and breast tumor tissues compared to non-tumorigenic cell line and adjacent normal breast tissues. According to ROC analysis, HERC4 positive expression was detected in 1/16 (6.3%) of normal breast tissue, in 3/13 (23.1%) of fibroadenoma, in 6/15 (40%) of intraductal carcinoma and 66/120 (55%) of invasive ductal carcinoma. Positive expression of HERC4 was positively correlated with pT status, pN status, clinical stage and histological grade of patients with invasive ductal carcinoma (p < 0.05).

Conclusions

Our findings suggest that HERC4 was a significant diagnostic marker for invasive ductal carcinoma of the breast.

RUNX3 is a prognostic marker and potential therapeutic target in human breast cancer

PURPOSE

To evaluate the role of RUNX3 in breast cancer pathogenesis, we examined the RUNX3 expression in breast cancer tissues and analyzed the correlation between RUNX3 expression and clinicopathologic variables and patients survival.

METHODS

We evaluated the RUNX3 expression by immunohistochemistry using a tissue microarray containing 256 specimens of breast cancer patients. We also studied the role of RUNX3 in cell migration and invasion by performing cell migration and invasion assay. Differential expression of metastasis-related genes after RUNX3 restoration was analyzed using the Human Tumor Metastasis PCR Array.

RESULTS

The RUNX3 expression was significantly correlated with breast cancer histology grade (P = 0.000), and low RUNX3 expression strongly correlated with worse 5-year overall and disease-specific survival rates (P = 0.000 and P = 0.001, respectively). Furthermore, we found that RUNX3 restoration suppressed breast cancer metastasis by controlling cell migration and invasion capacity. Finally, gene expression profiles of RUNX3-549 and Ctrl-549 cells showed matrix metalloproteinase-2 (MMP-2) was the most significant gene among the 84 metastasis-related genes influenced by RUNX3 reintroduction.

CONCLUSIONS

Reduced RUNX3 expression is significantly correlated with breast cancer progression and predicts worse survival. RUNX3 regulates breast cancer cell migration and invasion through the MMP-2 pathway.

Clinical relevance of cyclooxygenase-2 and matrix metalloproteinases (MMP-2 and MT1-MMP) in human breast cancer tissue

Breast cancer (BC) is the most common neoplasm among women in most developed countries, including Egypt. Elevated levels of certain proteins in human BC are associated with unfavorable prognosis and progressive stages of the disease. The aim of our study was to evaluate the protein expression profile and prognostic significance of cyclooxygenase-2 (COX-2), matrix metalloproteinase-2 (MMP-2), MMP-9 and membrane type 1-MMP (MT1-MMP) and their interaction in operable BC patients. The protein expression of COX-2, MMP-2 and MT1-MMP were evaluated by western blot technique, whereas enzymatic activity of MMP-2 and MMP-9 was determined by zymography in 47 breast cancer patients as well as normal adjacent tissues. Also, the correlation between these proteins and age, tumor size, LN stage, TNM stage, estrogen receptor, progesterone receptor, disease-free survival, and overall survival (OS) has been investigated. As compared to adjacent normal tissues, COX-2, MMP-2 and MT1-MMP were over-expressed in 43, 64, and 60 % of tumor tissues, respectively. In the same pattern, the activity of MMP-2 (62 %) and MMP-9 (45 %) was elevated in BC tissues. Multivariate analysis showed a positive correlation between the protein expression of COX-2, MMP-2, and MT1-MMP and the activity of MMP-2 and MMP-9 in BC patients. However, the enzymatic activity showed no correlation with clinicopathological features. This study confirms the preclinical evidence that COX-2 increased the expression of MT1-MMP, which in turn activates MMP-2. The lack of correlation with clinicopathological features, OS or disease-free survival ascertains the complexity of tumor progression and metastasis with many pro- and counter regulatory factors.

Avaliação imunoistoquímica dos receptores de estrogênio e progesterona no câncer de mama, pré e pós-quimioterapia neoadjuvante

OBJETIVO: Avaliar a imunoexpressão dos receptores de estrogênio e progesterona em biópsias e peças cirúrgicas de pacientes com câncer de mama pré e pós-quimioterapia neoadjuvante e correlacionar suas alterações com o padrão de resposta à quimioterapia e diagnóstico de menopausa. MÉTODOS: Selecionaram-se 47 pacientes com diagnóstico histopatológico de carcinoma primário de mama localmente avançado. Para cada paciente existiam dois blocos: o espécime da biópsia e o da ressecção cirúrgica. A partir destes blocos foi avaliada a expressão dos receptores hormonais por imunoistoquímica com a técnica da streptoavidina-biotina-imunoperoxidase e anticorpos primários anti-RE e anti-RP. A análise estatística utilizou o teste paramétrico t de Student e o não-paramétrico exato de Fisher, com nível de significância de 5%. RESULTADOS: Das 47 pacientes, 30 apresentavam imunoexpressão positiva dos receptores hormonais. Observou-se redução significativa tanto nos níveis de receptor de estrogênio e progesterona quanto em sua imunoexpressão. Em 53,3% observaram-se mudanças nos níveis expressos de receptor de estrogênio, 56,6% em receptor de progesterona, 26,6% na imunoexpressão do receptor de estrogênio e 33,3% na imunoexpressão do receptor de progesterona. Não foi encontrada significância estatística ao correlacionar-se a influência da resposta à quimioterapia e do diagnóstico de menopausa nas pacientes com a variação na expressão dos receptores hormonais. CONCLUSÃO: A quimioterapia neoadjuvante alterou significativamente a imunoexpressão dos receptores hormonais nas pacientes da amostra, reduzindo sua positividade nas células tumorais.

Analysis of matrix metalloproteinase-1 gene polymorphisms and expression in benign and malignant breast tumors

A guanine insertion polymorphism in matrix metalloproteinase-1 promoter (MMP-1 2G) is linked to early onset and aggressiveness in cancer. We determined the role of MMP-1 2G on MMP-1 expression and breast cancer severity in patients with breast diseases. We observed no significant difference in genotype distribution among different disease groups. However, MMP-1 expression was significantly higher in atypical ductal hyperplasia than in benign breast disease and in invasive breast cancer compared to in situ breast cancer. MMP-1 2G insertion polymorphism in the invasive group also correlated significantly with the expression of MMP-1 and breast cancer prognostic markers HER2 and P53.

ATP synthase ecto-α-subunit: a novel therapeutic target for breast cancer

Background

Treatment failure for breast cancer is frequently due to lymph node metastasis and invasion to neighboring organs. The aim of the present study was to investigate invasion- and metastasis-related genes in breast cancer cells in vitro and in vivo. Identification of new targets will facilitate the developmental pace of new techniques in screening and early diagnosis. Improved abilities to predict progression and metastasis, therapeutic response and toxicity will help to increase survival of breast cancer patients.

Methods

Differential protein expression in two breast cancer cell lines, one with high and the other with low metastatic potential, was analyzed using two-dimensional liquid phase chromatographic fractionation (Proteome Lab PF 2D system) followed by matrix-assisted laser desorption/time-of-flight mass spectrometry (MALDI-TOF/MS).

Results

Up regulation of α-subunit of ATP synthase was identified in high metastatic cells compared with low metastatic cells. Immunohistochemical analysis of 168 human breast cancer specimens on tissue microarrays revealed a high frequency of ATP synthase α-subunit expression in breast cancer (94.6%) compared to normal (21.2%) and atypical hyperplasia (23%) breast tissues. Levels of ATP synthase expression levels strongly correlated with large tumor size, poor tumor differentiation and advanced tumor stages (P < 0.05). ATP synthase α-subunit over-expression was detected on the surface of a highly invasive breast cancer cell line. An antibody against the ATP synthase α-subunit inhibited proliferation, migration and invasion in these breast cancer cells but not that of a non-tumor derived breast cell line.

Conclusions

Over-expression of ATP synthase α-subunit may be involved in the progression and metastasis of breast cancer, perhaps representing a potential biomarker for diagnosis, prognosis and a therapeutic target for breast cancer. This finding of this study will help us to better understand the molecular mechanism of tumor metastasis and to improve the screening, diagnosis, as well as prognosis and/or prediction of responses to therapy for breast cancer.

Rhein inhibits angiogenesis and the viability of hormone-dependent and -independent cancer cells under normoxic or hypoxic conditions in vitro

Hypoxia is a hallmark of solid tumors, including breast cancer, and the extent of tumor hypoxia is associated with treatment resistance and poor prognosis. Considering the limited treatment of hypoxic tumor cells and hence a poor prognosis of breast cancer, the investigation of natural products as potential chemopreventive anti-angiogenic agents is of paramount interest. Rhein (4,5-dihydroxyanthraquinone-2-carboxylic acid), the primary anthraquinone in the roots of Cassia alata L., is a naturally occurring quinone which exhibits a variety of biologic activities including anti-cancer activity. However, the effect of rhein on endothelial or cancer cells under hypoxic conditions has never been delineated. Therefore, the aim of this study was to investigate whether rhein inhibits angiogenesis and the viability of hormone-dependent (MCF-7) or -independent (MDA-MB-435s) breast cancer cells in vitro under normoxic or hypoxic conditions. Rhein inhibited vascular endothelial growth factor (VEGF(165))-stimulated human umbilical vein endothelial cell (HUVEC) tube formation, proliferation and migration under normoxic and hypoxic conditions. In addition, rhein inhibited in vitro angiogenesis by suppressing the activation of phosphatidylinositol 3-kinase (PI3K), phosphorylated-AKT (p-AKT) and phosphorylated extracellular signal-regulated kinase (p-ERK) but showed no inhibitory effects on total AKT or ERK. Rhein dose-dependently inhibited the viability of MCF-7 and MDA-MB-435s breast cancer cells under normoxic or hypoxic conditions, and inhibited cell cycle in both cell lines. Furthermore, Western blotting demonstrated that rhein inhibited heat shock protein 90alpha (Hsp90α) activity to induce degradation of Hsp90 client proteins including nuclear factor-kappa B (NF-κB), COX-2, and HER-2. Rhein also inhibited the expression of hypoxia-inducible factor-1 alpha (HIF-1α), vascular endothelial growth factor (VEGF(165)), epidermal growth factor (EGF), and the phosphorylation of inhibitor of NF-κB (I-κB) under normoxic or hypoxic conditions. Taken together, these data indicate that rhein is a promising anti-angiogenic compound for breast cancer cell viability and growth. Therefore, further studies including in vivo and pre-clinical need to be performed.

Analysis of breast cancer related gene expression using natural splines and the Cox proportional hazard model to identify prognostic associations

Many studies correlating gene expression data to clinical parameters assume a linear increase or decrease of the clinical parameter under investigation with the expression of a gene. We have studied genes encoding important breast cancer-related proteins using a model for survival-type data that is based on natural splines and the Cox proportional hazard model, thereby removing the linearity assumption. Expression data of 16 genes were studied in relation to metastasis-free probability in a cohort of 295 consecutive breast cancer patients treated at The Netherlands Cancer Institute. The independent predictive power for disease outcome of the 16 individual genes was tested in a multivariable model with known clinical and pathological risk factors. There is a linear relationship between increasing expression and a higher or lower hazard for distant metastasis for ESR1, ERBB4, VEGF, CCNE2, EZH2, and UPA; for ERBB2, ERBB3, CCND1, CCNE1, EED, CXCR4, CCR7, SDF1, and PAI1 there is no clear increase or decrease; and for EGFR there seems to be a non-linear relation. Multivariable analysis showed that the 70-gene prognosis profile outperforms all the other variables in the model (hazard-rate 5.4, 95% CI 2.5-11.7; P = 0.000018). EGFR-expression seems to have a non-linear relation with disease outcome, indicating that lower but also higher expression of EGFR are associated with worse outcome compared to intermediate expression levels; the other genes show no or a linear relation.

Automated quantitative assessment of HER-2/neu immunohistochemical expression in breast cancer

The expression of the HER-2/neu (HER2) gene, a member of the epidermal growth factor receptor family, has been shown to be a valuable prognostic indicator for breast cancer. However, interobserver variability has been reported in the evaluation of HER2 with immunohistochemistry. It has been suggested that automated computer-based evaluation can provide a consistent and objective evaluation of HER2 expression. In this manuscript, we present an automated method for the quantitative assessment of HER2 using digital microscopy. The method processes microscopy images from tissue slides with a multistage algorithm, including steps of color pixel classification, nuclei segmentation, and cell membrane modeling, and extracts quantitative, continuous measures of cell membrane staining intensity and completeness. A minimum cluster distance classifier merges the features to classify the slides into HER2 categories. An evaluation based on agreement analysis with pathologist-derived HER2 scores, showed good agreement with the provided truth. Agreement varied within the different classes with highest agreement (up to 90%) for positive (3+) slides, and lowest agreement (72%-78%) for equivocal (2+) slides which contained ambiguous scoring. The developed automated method has the potential to be used as a computer aid for the immunohistochemical evaluation of HER2 expression with the objective of increasing observer reproducibility.

The detection of circulating tumor cells of breast cancer patients by using multimarker (Survivin, hTERT and hMAM) quantitative real-time PCR

OBJECTIVES

To develop a specific, reliable assay for detecting circulating tumor cells (CTC) in peripheral blood of breast cancer patients.

DESIGN AND METHODS

94 breast cancer patients, 35 patients with benign breast tumor, 40 healthy individuals, and 25 patients with other solid tumors were evaluated by quantitative real-time reverse transcription-PCR (qRT-PCR) for detecting Survivin, hTERT, and hMAM mRNA in peripheral blood (PB) of breast cancer patients. In addition, analyses were carried out for their correlation with patients' clinicopathologic features.

RESULTS

The sensitivity of Survivin, hTERT, and hMAM mRNA in the PB of breast cancer patients was 36.2%, 59.6% and 33.0%, respectively. Survivin and hTERT were detected in the PB patients with solid tumors other than breast cancer, but hMAM mRNA was only detected in breast cancer patients. The sensitivity of three combined markers in the parallel test was 70.2%.Compared to that of single marker detection, the three combined markers' percentage was significantly higher. However, the specificity of three combined markers of serial test was 100%. The expression of the three mRNAs significantly correlated with TNM stage, and lymph node metastasis.

CONCLUSIONS

Survivin, hTERT and hMAM mRNA assays are powerful methods for detection of CTC of breast cancer patients. With combination of the three markers for detection of CTC of breast cancer, the parallel test increases the sensitivity. This analysis can offer a simple, noninvasive, and promising adjuvant tool for the early detection of micrometastatic tumor cells in breast cancer patients.

Quantitative real-time RT-PCR detection for survivin, CK20 and CEA in peripheral blood of colorectal cancer patients

OBJECTIVE

To establish a sensitive method for the early detection of circulating tumor cells (CTCs) in peripheral blood (PB) of colorectal cancer (CRC) patients.

METHODS

PB samples were collected from 156 CRC patients, 40 benign colorectal disease patients, 40 healthy individuals and 45 patients with other solid tumors. The combination of negative and positive immunomagnetic bead method was used to enrich cancer cells. Then, cytokeratin-20 (CK20), survivin and carcinoembryonic antigen (CEA) mRNA were detected by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). In addition, analyses were carried out for their correlation with patients' clinicopathologic features.

RESULTS

The positive rates of survivin, CK20 and CEA mRNA in the PB of CRC patients were 57.7, 47.4 and 39.1%, respectively, and the sensitivity increased from 39.1% of CEA mRNA alone to 60.9% of the combined panel. The expression of the three mRNAs in CRC patients was significantly higher than that in benign control and healthy volunteers, and the expression of survivin and CK20 was not significantly higher than that of patients with other solid tumors. However, the expression of CEA mRNA was significantly higher than that of patients with other solid tumors. The expression of survivin, CK20 and CEA mRNA was significantly correlated with Dukes stages and lymph node metastasis.

CONCLUSIONS

The combined use of negative and positive immunomagnetic beads followed by amplification of survivin, CK20 and CEA mRNA by means of qRT-PCR is a non-invasive and sensitive assay for the detection of circulating CRC cells. The combined panel improved the sensitivity of detection in CRC patients.

A highly sensitive and specific system for large-scale gene expression profiling

Background

Rapid progress in the field of gene expression-based molecular network integration has generated strong demand on enhancing the sensitivity and data accuracy of experimental systems. To meet the need, a high-throughput gene profiling system of high specificity and sensitivity has been developed.

Results

By using specially designed primers, the new system amplifies sequences in neighboring exons separated by big introns so that mRNA sequences may be effectively discriminated from other highly related sequences including their genes, unprocessed transcripts, pseudogenes and pseudogene transcripts. Probes used for microarray detection consist of sequences in the two neighboring exons amplified by the primers. In conjunction with a newly developed high-throughput multiplex amplification system and highly simplified experimental procedures, the system can be used to analyze >1,000 mRNA species in a single assay. It may also be used for gene expression profiling of very few (n = 100) or single cells. Highly reproducible results were obtained from duplicate samples with the same number of cells, and from those with a small number (100) and a large number (10,000) of cells. The specificity of the system was demonstrated by comparing results from a breast cancer cell line, MCF-7, and an ovarian cancer cell line, NCI/ADR-RES, and by using genomic DNA as starting material.

Conclusion

Our approach may greatly facilitate the analysis of combinatorial expression of known genes in many important applications, especially when the amount of RNA is limited.

Pathobiological features of breast tumours in the State of Kuwait: a comprehensive analysis

Background

Breast cancer accounts for 30.3% of all cancer types in Kuwaiti women. Death occurs in approximately 43% of these patients. Our goal was to conduct a comprehensive analysis of the pathobiological characteristics of the tumours in an attempt to determine any particular trend that could be present.

Methods

One hundred and sixty-six cases were included in this study. All the pathology reports and paraffin blocks pertaining to these cases were collected. Four micrometer sections were taken from each block, and immunostaining against Her-2, ER, and PgR was performed. Both the proportion and intensity of immunostaining were scored according to the Allred's method, and typing of the tumour was done according the WHO criteria regarding tumour classification. Grading of invasive carcinomas was done according to the modified Bloom-Richardson-Elston's method, and tumour stage was determined according to the criteria set by the American Joint Committee on Cancer.

Results

The mean age of the patients below 55 years was 40, as compared to 68 for those above 55 (p < 0.0001). More than half of the cases were in the right breast, and were surgically treated by total mastectomy with axillary clearance. The majority of the tumours had irregular (stellate) margins, was invasive, and had a surrounding breast tissue of adenosis or fibrocystic type. Their mitotic index was 10–20 or >20 with a marked to moderate nuclear pleomorphism. They were mostly grade II or III, sized 2–5 or > 5 cm, had absent or scanty tumour lymphocytes, and were stage II or III. The in situ tumours were mainly ductal carcinoma (DCIS) of which comedo and cribriform were the major histological subtypes. The major histological subtypes of the invasive tumours were ductal-not otherwise specified, lobular, and tubular/cribriform. In this study, we also found a significant (p < 0.05) association between over expression of Her-2, lack of expression of ER and some of the characteristics mentioned above.

Conclusion

Breast cancer in Kuwait seems to be more aggressive than what is currently seen in Europe, North America, Australia, and parts of Asia. Further investigations regarding the features observed in this study need to be performed.

Serum organochlorines and breast cancer: a case-control study among African-American women

This population-based case-control study of African-American women (355 breast cancer case patients, 327 controls) examined the association between breast cancer and circulating levels of PCBs and dichlorodiphenyldichloroethene (DDE), a metabolite of DDT. Case patients were diagnosed with invasive breast carcinoma and interviewed between June 1995 and July 1998, and control subjects were identified by random digit dialing methods. Serum levels of DDE and total PCBs were adjusted for total lipid content. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable unconditional logistic regression methods. Effect modification by tumor receptor status and cancer treatment was investigated. Breast cancer risk was not associated with increasing quintiles of lipid-adjusted PCBs or DDE (highest versus lowest quintile adjusted for age, body mass index (BMI) and breastfeeding for DDE: OR = 1.02, 95% CI = (0.61, 1.72), p-trend = 0.74; for PCBs: OR = 1.01, 95% CI = (0.63, 1.63), p-trend = 0.56). Risk did not differ by strata of BMI, breastfeeding, parity, menopausal status or tumor receptor status. This study, the largest study of African-American women to date, does not support a role of DDE and total PCBs in breast cancer risk at the levels measured.

Reduced mRNA and protein expression of BCL-2 versus decreased mRNA and increased protein expression of BAX in breast cancer brain metastases: a real-time PCR and immunohistochemical evaluation

OBJECTIVES

Brain metastases are an increasingly common complication in breast cancer patients. Apoptosis regulating genes are promising candidates for further treatment options. We examined the mRNA and protein expression of p53, BCL-2 and BAX in breast cancer brain metastases versus primary tumors.

METHODS

In a two-step approach p53, BCL-2 and BAX mRNA expression in ductal invasive breast cancer brain metastases was examined by: (1) reverse transcription-polymerase chain reaction (RT-PCR) mRNA expression screening (band appearance in relation to an internal standard) and (2) quantitative real-time RT-PCR (CT-values in relation to an internal standard). Protein expression using immunohistochemistry. Results were compared with primary tumors.

RESULTS

We found significantly lower BCL-2 mRNA and protein expression in breast cancer brain metastases versus primary tumors. P53 mRNA and protein expression was also lower in metastases. However, this difference was only significant on mRNA but not on the protein level. BAX expression evaluation revealed was contradictory results: mRNA expression was significantly lower whereas protein expression was significantly higher in metastatic lesions.

DISCUSSION

The mRNA and protein expression of p53 and BCL-2 seems to be reduced in breast cancer brain metastases. BAX mRNA and protein may be regulated differentially in metastatic lesions.

Detection of Survivin-expressing circulating cancer cells in the peripheral blood of breast cancer patients by a RT-PCR ELISA

Survivin mRNA expression was detected in 69.2%-93.8% of primary breast carcinomas, but is rarely expressed in normal breast tissues and hematopoietic cells. The objective of this study was to investigate the significance that the detection of Survinin-expressing circulating breast cancer cells in the peripheral blood has on clinical outcomes. The detection method was based on a RT-PCR ELISA technique developed in our laboratory. Sixty-seven breast cancer patients in various stages and 135 normal healthy women were investigated. Survivin-expressing circulating cancer cells were detected in the peripheral blood samples from 34 (50.7%) out of 67 breast cancer patients, but not in the healthy women that were used as controls. The presence of Survivin-expressing circulating breast cancer cells was found to be significantly associated with various clinicopathological parameters such as vessel infiltration, histological grade, tumor size, nodal status, ER/PgR status, Her-2 status and clinical stages of the disease (P < 0.01). During a follow-up period of 36 months, 9 out of 11 (81.8%) breast cancer patients that had a positive Survivin-expressing at the time of the initial assay test suffered a relapse of the disease, whereas recurrence was only found in 2 out of 6 (33.3%) breast cancer patients that had a negative Survivin-expression. Thus, the detection of circulating cancer cells expressing Survivin mRNA could provide valuable information for the prediction of metastasis and recurrence of breast cancer.

Evaluation of the prognostic and predictive value of p53 and Bcl-2 in breast cancer patients participating in a randomized study with dose-dense sequential adjuvant chemotherapy

PURPOSE

To assess the prognostic and predictive significance of p53 and Bcl-2 protein expression in high risk patients with breast cancer treated with dose-dense sequential chemotherapy.

PATIENTS AND METHODS

From June 1997 until November 2000, 595 patients were randomized to three cycles of epirubicin (E) 110 mg/m2 followed by three cycles of paclitaxel (P) 250 mg/m2 followed by three cycles of 'intensified' CMF (cyclophosphamide 840 mg/m2, methotrexate 47 mg/m2 and fluorouracil 840 mg/m2) or to four cycles of E, followed by four cycles of CMF. p53 and Bcl-2 expression was investigated by immunohistochemistry in 392 and 397 patients respectively.

RESULTS

Positive expression of p53 was detected in 104 (26.5%) patients and was significantly associated with negative hormonal status, worse histologic grade, higher incidence of disease relapse and higher rate of death. p53 positive expression was a significant negative predictor of overall survival (OS) (P = 0.002) and disease-free survival (DFS) (P = 0.001). Negative expression of Bcl-2 was detected in 203 (51%) patients and was significantly associated with negative hormonal status. Multivariate analysis revealed that, positive p53 expression, higher number of positive nodes and worse tumor grade were related to significantly poorer OS and DFS.

CONCLUSIONS

For both treatments, p53 positive expression was a significant negative prognostic factor for OS and DFS while Bcl-2 was not. No predictive ability of p53 status or Bcl-2 status for paclitaxel treatment was evident.

Human kallikrein 10, a predictive marker for breast cancer

Our laboratory is involved in identifying genes that can be used as early diagnostic or prognostic markers in breast cancer. We previously identified a gene (NES1) that is expressed in normal but not in transformed mammary epithelial cells (MECs). NES1 is located on chromosome 19q13.4 within the kallikrein locus and thus was designated as human kallikrein 10 (hK10), although we have been unable to detect any protease activity. Importantly, hK10 expression is decreased in a majority of breast cancer cell lines. Transfection of hK10 into hK10-negative breast cancer cells reduces the tumorigenicity. Using methylation-specific PCR and subsequent sequencing, we demonstrate a strong correlation between hypermethylation of hK10 and loss of mRNA expression. Further analysis showed that essentially 100% of normal breast specimens had hK10 expression, whereas 46% of ductal carcinoma in situ (DCIS) and the majority of infiltrating ductal carcinoma (IDC) samples lacked the hK10 mRNA. Importantly, hK10-negative DCIS diagnosed at the time of biopsy were subsequently diagnosed as IDC at the time of definitive surgery. It has been shown that hK10 protein expression is regulated by steroids. In addition to breast cancers, hK10 is downregulated in cervical cancer, prostate cancer and acute lymphocytic leukemia, whereas it is upregulated in ovarian cancers. These results point to the paradoxical role of hK10 in human cancers and underscore the importance of further studies of this kallikrein.

Diagnostic accuracy of canine scent detection in early- and late-stage lung and breast cancers

BACKGROUND

Lung and breast cancers are leading causes of cancer death worldwide. Prior exploratory work has shown that patterns of biochemical markers have been found in the exhaled breath of patients with lung and breast cancers that are distinguishable from those of controls. However, chemical analysis of exhaled breath has not shown suitability for individual clinical diagnosis.

METHODS

The authors used a food reward-based method of training 5 ordinary household dogs to distinguish, by scent alone, exhaled breath samples of 55 lung and 31 breast cancer patients from those of 83 healthy controls. A correct indication of cancer samples by the dogs was sitting/lying in front of the sample. A correct response to control samples was to ignore the sample. The authors first trained the dogs in a 3-phase sequential process with gradually increasing levels of challenge. Once trained, the dogs' ability to distinguish cancer patients from controls was then tested using breath samples from subjects not previously encountered by the dogs. The researchers blinded both dog handlers and experimental observers to the identity of breath samples. The diagnostic accuracy data reported were obtained solely from the dogs' sniffing, in double-blinded conditions, of these breath samples obtained from subjects not previously encountered by the dogs during the training period.

RESULTS

Among lung cancer patients and controls, overall sensitivity of canine scent detection compared to biopsy-confirmed conventional diagnosis was 0.99 (95% confidence interval [CI], 0.99, 1.00) and overall specificity 0.99 (95% CI, 0.96, 1.00). Among breast cancer patients and controls, sensitivity was 0.88 (95% CI, 0.75, 1.00) and specificity 0.98 (95% CI, 0.90, 0.99). Sensitivity and specificity were remarkably similar across all 4 stages of both diseases.

CONCLUSION

Training was efficient and cancer identification was accurate; in a matter of weeks, ordinary household dogs with only basic behavioral "puppy training" were trained to accurately distinguish breath samples of lung and breast cancer patients from those of controls. This pilot work using canine scent detection demonstrates the validity of using a biological system to examine exhaled breath in the diagnostic identification of lung and breast cancers. Future work should closely examine the chemistry of exhaled breath to identify which chemical compounds can most accurately identify the presence of cancer.

The impact of expression profiling on prognostic and predictive testing in breast cancer

Expression profiling has been extensively applied to the study of breast cancer and undoubtedly is changing the way breast cancer is perceived. Over the past few years, several groups have described prognostic "signatures" (gene lists) that are purported to be more accurate prognostic factors than well established clinical and pathological features. In addition, cDNA and oligonucleotide microarrays have also been used to devise predictive "signatures" in the setting of neoadjuvant chemotherapy setting. However, it seems that the enthusiasm with this new technology has led most of us to turn a blind eye to some serious methodological problems which are evident in landmark papers on breast cancer expression profiling. These issues include small and biased cohorts of patients, inappropriate statistical analysis and lack of thorough validation of the technology. In this review, we critically revisit the most relevant cDNA microarray studies on breast cancer prognosis and prediction published to date. Although the results are promising, further optimisation and standardisation of the technique and properly designed clinical trials are required before microarrays can reliably be used as tools for clinical decision making.

The human kallikrein 10 promoter contains a functional retinoid response element

Human kallikrein 10 (hK10) protein is expressed in normal breast but is significantly downregulated in a majority of invasive breast cancers. Thus, understanding how hK10 expression is regulated is of substantial significance. In this study, we analyzed the promoter region of hK10 using a website software (TRANSFAC 3.0), which predicted three possible retinoic acid response elements (RAREs), RARE1 at -1041 (TGACCTCGTGATCC), RARE2 at -859 (TGACCTCCTATGA) and RARE3 at -765 (TGACCTCCTGTGA), each with a half-site of a canonical sequence (TGACCT; reverse complement AGGTCA). Using electrophoretic mobility shift assays and nucleotide competition analysis, as well as chromatin immunoprecipitation of the native hK10 promoter, we demonstrated specific binding of RXR only to RARE1. The functional importance of RARE in the hK10 promoter was demonstrated by retinoid induction of hk10 promoter-reporters; furthermore, mutation of RARE1 but not of RARE2 or RARE3 abolished the induction of the reporter. Finally, we demonstrated the induction of hK10 mRNA and protein expression upon retinoid treatment of cells. In view of the correlation of the downregulation of hK10 mRNA and protein with breast cancer progression, these findings suggest a potential approach to restore hK10 expression in cancer patients.

Flow cytometry: a new approach for the molecular profiling of breast cancer

The established method in prognosis of breast cancer includes detection of molecular markers, such as the estrogen receptor (ER), progesterone receptor (PR), and HER-2/neu. These markers are routinely checked via immunohistochemistry (IHC). HER-2/neu is also detected by fluorescent in situ hybridization (FISH). Flow cytometric analysis has not yet been used for detection of such markers. Flow cytometry was performed on four established breast cancer cell lines: MCF7, T47D, BT474, MDA-MB-231, and on one normal breast epithelial cell line: MCF10A. Flow cytometric analysis was used for the detection of ER, PR, HER-2/neu, epidermal growth factor receptor (EGFR), and E-cadherin. Currently, EGFR and E-cadherin are not standard predictive factors in determining survival of breast cancer patients, but both may be beneficial to prognosis. Cells undergoing flow cytometric analysis lost marker expression with increasing passage number. The highest expression was found at cells passaged 0-1 times. MCF7, T47D, and BT474 all had similar marker expression patterns. E-cadherin demonstrated a strongly positive pattern with marker expression of 85-92% among the three cell lines. ER, PR, and HER-2/neu demonstrated a weakly positive expression pattern when compared with E-cadherin. Marker expression ranged from 15 to 61%. These three cell lines were almost negative for expression of EGFR where expression ranged from 0 to 6%. MDA-MB-231 had almost no expression of all 5 markers, with positive values ranging from 0 to 5%. MCF10A had weak positive to almost negative expression values of ER, PR, HER-2/neu, and E-cadherin, which ranged from 3 to 13%. EGFR, both surface and cytoplasmic markers, again were not expressed in MCF10A cells with an expression value of <1%. We found that ER, PR, and HER-2/neu marker expressions in 5 out of 5 cell lines were consistent with established expression patterns. EGFR and E-cadherin expression in 4 out of 5 cell lines were also consistent with established expression patterns. We have shown that flow cytometry provides quantitative data on expression patterns of important prognostic markers in breast cancer.

Breast carcinomas fulfill the Warburg hypothesis and provide metabolic markers of cancer prognosis

The aim of this study was to investigate selected proteomic markers of the metabolic phenotype of breast carcinomas as prognostic markers of cancer progression. For this purpose, a series of 101 breast carcinomas and 13 uninvolved breast samples were examined for quantitative differences in protein expression of mitochondrial and glycolytic markers. The beta-subunit of the mitochondrial H(+)-ATP synthase (beta-F1-ATPase) and heat shock protein 60 (Hsp60), and the glycolytic glyceraldehyde-3-phosphate dehydrogenase, pyruvate kinase and lactate dehydrogenase were identified by immunological techniques. Correlations of the expression level of the protein markers and of the ratios derived from them were established with the clinicopathological information of the tumors and the follow-up data of the patients. The metabolic proteome of breast cancer specimens revealed a pronounced shift towards an enhanced glycolytic phenotype concurrent with a profound alteration on the mitochondrial beta-F1-ATPase/Hsp60 ratio when compared with normal samples. Discriminant analysis using markers of the metabolic signature as predictor variables revealed a classification sensitivity of approximately 97%. Kaplan-Meier survival analysis showed that several of the proteomic variables significantly correlated with overall and disease-free survival of the patients. The expression level of beta-F1-ATPase per se allowed the identification of a subgroup of breast cancer patients with significantly worse prognosis. Multivariate Cox regression analysis indicated that tumor expression of beta-F1-ATPase is a significant marker independent from clinical variables to assess the prognosis of the patients. We conclude that the alteration of the mitochondrial and glycolytic proteomes is a hallmark feature of breast cancer further providing relevant markers to aid in the prognosis of breast cancer patients.

Molecular Markers and Prostate Cancer Prognosis

Prostate cancer is the most common malignancy among American men and is the second-leading cause of cancer-related mortality. Although radical prostatectomy and radiation therapy offer hope for cure for the majority of men with localized tumors, we continue to lack the tools to definitively determine which cancers need to be treated, which cancers will recur after treatment, and which cancers will behave aggressively when they have metastasized. Recent breakthroughs in molecular biology have led to the identification of a number of potential biomarkers for prostate cancer, many of which have been suggested to have prognostic significance. Eventually, combinations of these markers will hopefully enable us to more rationally facilitate counseling and direct management for men with prostate cancer.

A combination of HER-2 status and the St. Gallen classification provides useful information on prognosis in lymph node-negative breast carcinoma

BACKGROUND

Adjuvant chemotherapy for patients with lymph node-negative breast carcinoma is being recommended currently based on the St. Gallen classification. The prognostic importance of HER-2 status in patients with lymph node-negative breast carcinoma has been investigated extensively, with contradictory results. The authors investigated the clinical relevance of HER-2 overexpression when combined with the St. Gallen classification in lymph node-negative breast carcinoma.

METHODS

The medical records of patients with breast carcinoma negative for lymph node involvement who underwent surgery between January 1995 and December 2000 at the Seoul National University College of Medicine (Seoul, Korea) were reviewed retrospectively. Risk groups based on the St. Gallen classification were categorized as average or minimal risk. The prognostic values of HER-2 in combination with the St. Gallen classification were analyzed with respect to disease-free survival (DFS) rates.

RESULTS

A total of 906 patients were eligible for analysis. The overall 7-year DFS rate was 87.5%. The 7-year DFS rates for patients with HER-2-positive and HER-2-negative tumors were, respectively, 77.9% and 91.2% (P = 0.002). The 7-year DFS rates for patients with average and minimal risk group were 85.0% and 97.9%, respectively. The authors found that HER-2 overexpression significantly predicted the risk of disease recurrence (odds ratio = 3.03 [95% confidence interval, 1.63-5.63]). Furthermore, when HER-2 status was combined with the St. Gallen classification, the DFS rate of the HER-2-positive average risk group was 73.3% compared with 88.4% for the HER-2-negative average risk group (P = 0.007).

CONCLUSIONS

The combination of HER-2 overexpression and the St. Gallen classification was more useful than either alone to predict the risk of disease recurrence in patients with lymph node-negative breast carcinoma.

Use of three-dimensional basement membrane cultures to model oncogene-induced changes in mammary epithelial morphogenesis

The development of breast carcinomas involves a complex set of phenotypic alterations in breast epithelial cells and the surrounding microenvironment. While traditional transformation assays provide models for investigating certain aspects of the cellular processes associated with tumor initiation and progression, they do not model alterations in tissue architecture that are critically involved in tumor development. In this review, we provide examples of how three-dimensional (3D) cell culture models can be utilized to dissect the pathways involved in the development of mammary epithelial structures and to elucidate the mechanisms responsible for oncogene-induced phenotypic alterations in epithelial behavior and architecture. Many normal mammary epithelial cell lines undergo a stereotypic morphogenetic process when grown in the presence of exogenous matrix proteins. This 3D morphogenesis culminates in the formation of well-organized, polarized spheroids, and/or tubules that are highly reminiscent of normal glandular architecture. In contrast, transformed cell lines isolated from mammary tumors exhibit significant deviations from normal epithelial behavior in 3D culture. We describe the use of 3D models as a method for both reconstructing and deconstructing the cell biological and biochemical events involved in mammary neoplasia.