Activation of epithelial-mesenchymal transition process during breast cancer progression - the impact of molecular subtype and stromal composition.

Breast cancer (BC) is a heterogeneous disease with different molecular subtypes, which can be defined by oestrogen (ER), progesterone (PR) and human epidermal growth factor (HER2) receptors' status as luminal, HER2+ and triple negative (TNBC). Molecular subtypes also differ in their epithelial-mesenchymal phenotype, which might be related to their aggressiveness, as activation of the epithelial-mesenchymal transition (EMT) is linked with increased ability of cancer cells to survive and metastasize. Nevertheless, the reverse process of mesenchymal-epithelial transition was shown to be required to sustain metastatic colonization.

Clinical and Biological Significance of Gene Alteration and Estrogen Receptors Isoforms Expression in Breast Cancer Patients.

The amplification of estrogen receptor alpha (ERα) encoded by the gene has been described as having a prognostic role in breast cancer patients. However, increased dosage of the gene (tested by real-time PCR) is also observed in ER-negative breast cancers, which might suggest the expression of alternative isoforms of ERα (other than classical ERα of 66 kDa). In the current work, we have investigated the gene dosage in 402 primary breast cancer patients as well as the expression of ERα isoforms-ERα66 and ERα36-on mRNA and protein levels.

Spectrum of Epithelial-Mesenchymal Transition Phenotypes in Circulating Tumour Cells from Early Breast Cancer Patients.

Circulating tumour cells (CTCs) can provide valuable prognostic information in a number of epithelial cancers. However, their detection is hampered due to their molecular heterogeneity, which can be induced by the epithelial-mesenchymal transition (EMT) process. Therefore, current knowledge about CTCs from clinical samples is often limited due to an inability to isolate wide spectrum of CTCs phenotypes.

Aggressive Phenotype of Cells Disseminated via Hematogenous and Lymphatic Route in Breast Cancer Patients.

Intratumoral heterogeneity of breast cancer remains a major challenge in successful treatment. Failure of cancer therapies can also be accredited to inability to systemically eradicate cancer stem cells (CSCs). Recent evidence points to the role of epithelial-mesenchymal transition (EMT) in expanding the pool of tumor cells with CSCs features.

CD99 correlates with low cyclin D1, high topoisomerase 2 status and triple negative molecular phenotype but is prognostically irrelevant in breast carcinoma.

CD99 is a protein initially described in the Ewing sarcoma family of tumors, but growing evidence has shown its expression in other tumors of mesenchymal, hematopoietic and even epithelial origin. Some articles report CD99 in metaplastic carcinoma of the breast, a subtype of breast carcinoma (BC) with pronounced epithelial to mesenchymal (EMT) phenotype. Our aim was to analyse the potential relationship between CD99 and selected EMT (vimentin, E-cadherin, Twist) and proliferation markers (Ki-67, c-myc, cyclin D1, topoisomerase 2), molecular subtypes of BC, as well as overall survival (OS) and progression-free survival (PFS).

Stromal expression of ALDH1 in human breast carcinomas indicates reduced tumor progression.

Interactions between cancer cells and microenvironment are emerging issue in tumor progression. Aldehyde dehydrogenase 1 (ALDH1) is a recognized cancer stem cell marker but little is known about its role in intratumoral stroma. Therefore, we focused on ALDH1 expression in tumor-associated stroma of breast carcinomas (BrCa).

Epithelial-mesenchymal transition markers in lymph node metastases and primary breast tumors - relation to dissemination and proliferation.

Epithelial-mesenchymal transition (EMT) was shown to enhance metastatic abilities of cancer cells, but it remains elusive in clinical samples. Moreover, EMT is rarely studied in lymph node metastases (LNM), thus limiting our understanding of its role outside of the primary tumors (PT). We collected a set of samples including triplets - PT, circulating tumor cells (CTCs)-enriched blood samples and LNM from 108 early breast cancer patients.

Mesenchymal phenotype of CTC-enriched blood fraction and lymph node metastasis formation potential.

Introduction: Circulating tumor cells (CTCs) that present mesenchymal phenotypes can escape standard methods of isolation, thus limiting possibilities for their characterization. Whereas mesenchymal CTCs are considered to be more malignant than epithelial CTCs, factors responsible for this aggressiveness have not been thoroughly defined. This study analyzed the molecular profile related to metastasis formation potential of CTC-enriched blood fractions obtained by marker unbiased isolation from breast cancer patients without (N-) and with lymph nodes metastases (N+).

Heterogeneity of mesenchymal markers expression-molecular profiles of cancer cells disseminated by lymphatic and hematogenous routes in breast cancer.

Breast cancers can metastasize via hematogenous and lymphatic routes, however in some patients only one type of metastases are detected, suggesting a certain proclivity in metastatic patterns. Since epithelial-mesenchymal transition (EMT) plays an important role in cancer dissemination it would be worthwhile to find if a specific profile of EMT gene expression exists that is related to either lymphatic or hematogenous dissemination. Our study aimed at evaluating gene expression profile of EMT-related markers in primary tumors (PT) and correlated them with the pattern of metastatic spread.

Prognostic significance of ESR1 amplification and ESR1 PvuII, CYP2C19*2, UGT2B15*2 polymorphisms in breast cancer patients.

Introduction: Amplification of the ESR1 gene, coding for estrogen receptor alpha, was shown to predict responsiveness to tamoxifen, however its prognostic impact in breast cancer patients has not been thoroughly investigated. Other factors that could contribute to responsiveness to tamoxifen treatment are polymorphisms in ESR1 gene and genes involved in tamoxifen metabolism. The aim of this study was to assess the prognostic role of ESR1 gene dosage in a consecutive group of breast cancer patients and to correlate this feature with clinico-pathological factors.

Are bilateral breast cancers different from breast cancers coexisting with ovarian cancer? An immunohistochemical analysis aimed at intrinsic tumor phenotype.

Rationale: Bilateral breast cancers (BBC) and breast cancers coexisting with ovarian cancer (BOCS) are associated with genetic predisposition more frequently than sporadic cases. We compared the phenotypes of these tumors to better understand their pathomechanisms and aid the guiding of their clinical management.

Materials And Methods: Tumor morphology and expression of ER, PgR, HER2, Ki67, CK5/6, E-cadherin, vimentin and EGFR were assessed in a tissue microarray containing cores from 174 BBC, 23 BOCS and 2 BBC + BOCS.

Expression of epithelial to mesenchymal transition-related markers in lymph node metastases as a surrogate for primary tumor metastatic potential in breast cancer.

Background: Breast cancers are phenotypically and genotypically heterogeneous tumors containing multiple cancer cell populations with various metastatic potential. Aggressive tumor cell subpopulations might more easily be captured in lymph nodes metastases (LNM) than in primary tumors (PT). We evaluated mRNA and protein levels of master EMT regulators: TWIST1, SNAIL and SLUG, protein levels of EMT-related markers: E-cadherin, vimentin, and expression of classical breast cancer receptors: HER2, ER and PgR in PT and corresponding LNM.

Prognostic significance of TOP2A gene dosage in HER-2-negative breast cancer.

Background: Previous studies showed the prognostic and predictive impact of human epidermal growth factor receptor 2 (HER-2) gene alterations analyzed separately and jointly with topoisomerase II α (TOP2A) gene alterations; however, the role of TOP2A gene abnormalities alone has not been thoroughly investigated. Additionally, TOP2A aberrations were typically studied in HER-2-positive (HER-2(+)) tumors because these genes are frequently coamplified. Therefore, the knowledge concerning the impact of TOP2A abnormalities in HER-2-negative (HER-2(-)) patients is scarce.

CD73 expression as a potential marker of good prognosis in breast carcinoma.

Ecto-5'-nucleotidase (CD73) is a membrane-bound enzyme, which catalyzes the conversion of adenosine monophosphate to adenosine. CD73 has been postulated to play an important role in carcinogenesis, as adenosine promotes tumor progression and CD73-expressing cancer cell lines are more aggressive. However, other studies have shown that activated adenosine receptors may also inhibit cell proliferation.

Prognostic value of TOP2A gene amplification and chromosome 17 polysomy in early breast cancer.

The aim of this study was to analyze the occurrence of TOP2A gene amplification and chromosome 17 polysomy in patients with early breast cancer and to correlate the status of these alterations with the prognostic significance expressed as patients' clinical features and survival. Such concurrent analyses of TOP2A gene status and chromosome 17 polysomy have not been performed before. Study group included 149 consecutive stage I-III patients administered standard multimodality treatment.

Pattern of care in locally advanced breast cancer: focus on local therapy.

Background And Methods: The optimal treatment of locally advanced breast cancer (LABC) remains undetermined. We analyzed factors influencing local therapy in LABC in a pooled material including three large clinical series.

Results: Of a total of 787 patients, local therapy was given in 604, surgery in 184, radiotherapy in 69, and a combination thereof in 351.

Clinical evaluation of developed PCR-based method with hydrolysis probes for TOP2A copy number evaluation in breast cancer samples.

Objectives: The objective of this study was to develop a new real time PCR-based method for quantitative detection of topoisomerase II alpha (TOP2A) aberrations and to evaluate its clinical utility in breast cancer.

Design And Methods: The method applied dually labelled hydrolysis probes and Pfaffl quantification method. The study group consisted of 83 consecutive breast cancer patients.

Gene copy numbers of HER family in breast cancer.

Aim: The aim of the study was to analyze the occurrence of abnormal gene copy numbers of all HER oncogenes and to correlate these alterations to other clinicopathological variables in a consecutive series of 225 breast cancer patients.

Methods: Gene copy number of HER oncogenes was analyzed with double differential polymerase chain reaction (ddPCR). Statistical analysis was performed with a set of nonparametric tests.

Postoperative adjuvant chemotherapy followed by adjuvant tamoxifen versus nil for patients with operable breast cancer: a randomised phase III trial of the European Organisation for Research and Treatment of Cancer Breast Group.

Background: The contribution of adjuvant tamoxifen in breast cancer patients after receiving adjuvant chemotherapy is not fully established. We investigated the impact of tamoxifen, given sequentially after completion of adjuvant chemotherapy in patients with operable breast cancer.

Patients And Methods: Between March 1991 and June 1999, 1863 women with stages I-IIIA operable breast cancer who had undergone surgery and completed six cycles of adjuvant combination chemotherapy with either CMF, CAF, CEF, FAC or FEC were randomised to receive either tamoxifen 20 mg daily for 3 years or no further treatment.

(CA)n microsatellite polymorphism of ERBB-1 in breast cancer.

The aim of this study was to determine polymorphism of repeated sequences (CA)(n) in the ERBB-1 gene. The study group included 197 breast cancer patients and 180 healthy women. DNA was isolated from fresh-frozen tumour tissue and from peripheral blood.

Health-related quality of life in survivors of locally advanced breast cancer: an international randomised controlled phase III trial.

Background: Dose-intensive chemotherapy has generated much interest in the treatment of patients with locally advanced breast cancer because it might offer a survival benefit. We aimed to compare the effects of such an approach with those of standard chemotherapy on health-related quality of life (HRQOL).

Methods: 224 patients with locally advanced breast cancer were randomly assigned to 75 mg/m(2) cyclophosphamide given orally on days 1-14, and 60 mg/m(2) epirubicin and 500 mg/m(2) fluorouracil both given intravenously on days 1 and 8, for six cycles every 28 days (6 months' treatment; standard treatment) and 224 patients to 830 mg/m(2) cyclophosphamide and 120 mg/m(2) epirubicin both given intravenously on day 1, and 5 microg/kg filgrastim per day given subcutaneously on days 2-13, for six cycles every 14 days (3 months' treatment; dose-intensive treatment).

Modified direct-double-differential PCR for gene dosage quantification of HER2.

HER2 amplification and/or overexpression in breast cancer are adverse prognostic factors and can predict the response to trastuzumab therapy. As assessment of HER2 status in breast cancer is of great importance for clinical decision-making, it is crucial to have reliable methods to quantify HER2. In the present project, we have developed a modification of the direct-double-differential PCR method (dddPCR) for gene dosage quantification of HER2 in breast cancer samples.

Gemcitabine, epirubicin, and paclitaxel versus fluorouracil, epirubicin, and cyclophosphamide as first-line chemotherapy in metastatic breast cancer: a Central European Cooperative Oncology Group International, multicenter, prospective, randomized phase III trial.

Background: The objectives of this phase III trial were to compare the time to progressive disease (TtPD), overall response rate (ORR), overall survival, and toxicity of gemcitabine, epirubicin, and paclitaxel (GET) versus fluorouracil (FU), epirubicin, and cyclophosphamide (FEC) as first-line therapy in patients with metastatic breast cancer (MBC).

Patients And Methods: Female patients aged 18 to 75 years with stage IV and measurable MBC were enrolled and randomly assigned to either gemcitabine (1,000 mg/m(2), days 1 and 4), epirubicin (90 mg/m(2), day 1), and paclitaxel (175 mg/m(2), day 1) or FU (500 mg/m(2), day 1), epirubicin (90 mg/m(2), day 1), and cyclophosphamide (500 mg/m(2), day 1). Both regimens were administered every 21 days for a maximum of eight cycles.

Radiotherapy for breast cancer in patients undergoing breast reconstruction or augmentation.

Due to increasing indications for postmastectomy radiotherapy and a growing demand for breast reconstruction or augmentation, increasing numbers of patients are currently being exposed to both these treatments. In view of the wide range of available techniques for breast reconstruction, either prosthetic or autologous, and their various sequencing in relation to radiotherapy, physicians can be faced with numerous clinical situations requiring comprehensive knowledge of the topic. This review discusses physical, radiobiological and clinical aspects of combining breast reconstruction and radiotherapy.

Health-related quality of life parameters as prognostic factors in a nonmetastatic breast cancer population: an international multicenter study.

Purpose: The purpose of this research was to evaluate whether baseline health-related quality of life (HRQOL) parameters are prognostic factors for survival in locally advanced breast cancer patients. Although the literature highlights the important role of HRQOL parameters in predicting survival in advanced metastatic disease, little evidence exists for earlier stages.

Patients And Methods: The overall sample consisted of 448 patients randomly assigned to receive cyclophosphamide, epirubicin, and fluorouracil versus epirubicin, cyclophosphamide, and granulocyte colony-stimulating factor.