Sarah Schott

Circulating microRNAs in plasma as early detection markers for breast cancer

In recent years, circulating miRNAs have attracted a great deal of attention as promising novel markers for various diseases. Here, we investigated their potential to serve as minimally invasive, early detection markers for breast cancer in blood plasma. We profiled miRNAs extracted from the plasma of early stage breast cancer patients (taken at the time‐point of diagnosis) and healthy control individuals using TaqMan low‐density arrays (TLDA). Selected candidates identified in the initial screen were further validated in an extended study cohort of 207 individuals including 127 sporadic breast cancer cases and 80 healthy controls via RT‐qPCR. Four miRNAs (miR‐148b, miR‐376c, miR‐409‐3p and miR‐801) were shown to be significantly upregulated in the plasma of breast cancer patients. ROC curve analysis showed that the combination of only three miRNAs (miR‐148b, miR‐409‐3p and miR‐801) had an equal discriminatory power between breast cancer cases and healthy controls as all four miRNAs together (AUC = 0.69). In conclusion, the identified miRNAs might be of potential use in the development of a multimarker blood‐based test to complement and improve early detection of breast cancer. Such a multimarker blood test might for instance provide a prescreening tool, especially for younger women, to facilitate decisions about which individuals to recommend for further diagnostic tests.

Circulating miRNAs as Surrogate Markers for Circulating Tumor Cells and Prognostic Markers in Metastatic Breast Cancer

Purpose: The use of circulating tumor cells (CTC) as a prognostic marker in metastatic breast cancer (MBC) has been well established. However, their efficacy and accuracy are still under scrutiny mainly because of methods of their enrichment and identification. We hypothesized that circulating miRNAs can predict the CTC status of patients with MBC, and tested for the same. Furthermore, we aimed at establishing a panel of circulating miRNAs capable of differentiating MBC cases from healthy controls. Experimental Design: Circulating miRNAs from plasma of CTC-positive and CTC-negative patients with MBC, and healthy controls, were profiled by TaqMan Human MicroRNA arrays. Candidates from the initial screen were validated in an extended cohort of 269 individuals (61 CTC-positive, 72 CTC-negative, 60 CTC-low MBC cases, and 76 controls). Results: CTC-positive had significantly higher levels of miR-141, miR-200a, miR-200b, miR-200c, miR-203, miR-210, miR-375, and miR-801 than CTC-negative MBC and controls (P < 0.00001), whereas miR-768-3p was present in lower amounts in MBC cases (P < 0.05). miR-200b was singled out as the best marker for distinguishing CTC-positive from CTC-negative patients (AUC 0.88). We identified combinations of miRNAs for differentiating MBC cases from controls (AUC 0.95 for CTC-positive; AUC 0.78 for CTC-negative). Combinations of miRNAs and miR-200b alone were found to be promising prognostic marker for progression-free and overall survival. Conclusion: This is the first study to document the capacity of circulating miRNAs to indicate CTC status and their potential as prognostic markers in patients with MBC. Clin Cancer Res; 18(21); 5972–82. ©2012 AACR.

Plasma microRNA panel for minimally invasive detection of breast cancer.

Over the last few years, circulating microRNAs (miRNAs) have emerged as promising novel and minimally invasive markers for various diseases, including cancer. We already showed that certain miRNAs are deregulated in the plasma of breast cancer patients when compared to healthy women. Herein we have further explored their potential to serve as breast cancer early detection markers in blood plasma. Circulating miR-127-3p, miR-376a and miR-652, selected as candidates from a miRNA array-based screening, were found to be associated with breast cancer for the first time (n = 417). Further we validated our previously reported circulating miRNAs (miR-148b, miR-376c, miR-409-3p and miR-801) in an independent cohort (n = 210) as elevated in the plasma of breast cancer patients compared to healthy women. We described, for the first time in breast cancer, an over-representation of deregulated miRNAs (miR-127-3p, miR-376a, miR-376c and miR-409-3p) originating from the chromosome 14q32 region. The inclusion of patients with benign breast tumors enabled the observation that miR-148b, miR-652 and miR-801 levels are even elevated in the plasma of women with benign tumors when compared to healthy controls. Furthermore, an analysis of samples stratified by cancer stage demonstrated that miR-127-3p, miR-148b, miR-409-3p, miR-652 and miR-801 can detect also stage I or stage II breast cancer thus making them attractive candidates for early detection. Finally, ROC curve analysis showed that a panel of these seven circulating miRNAs has substantial diagnostic potential with an AUC of 0.81 for the detection of benign and malignant breast tumors, which further increased to 0.86 in younger women (up to 50 years of age).

Evaluation of Virtual Touch Tissue Imaging Quantification, a New Shear Wave Velocity Imaging Method, for Breast Lesion Assessment by Ultrasound

Objectives. To evaluate virtual touch tissue imaging quantification (VTIQ) as a new elastography method concerning its intra- and interexaminer reliability and its ability to differentiate benign from malignant breast lesions in comparison to and in combination with ultrasound (US) B-mode breast imaging reporting and data system (BI-RADS) assessment. Materials and Methods. US and VTIQ were performed by two examiners in 103 women with 104 lesions. Intra- and interexaminer reliability of VTIQ was assessed. The area under the receiver operating curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of BIRADS, VTIQ, and combined data were compared. Results. Fifty-four of 104 lesions were malignant. Intraexaminer reliability was consistent, and interexaminer agreement showed a strong positive correlation (r = 0.93). The mean VTIQ values in malignant lesions were significantly higher than those in benign (7.73 m/s ± 1.02 versus 4.46 m/s ± 1.87; P < 0.0001). The combination of US-BIRADS with the optimal cut-off for clinical decision making of 5.18 m/s yielded a sensitivity of 98%, specificity of 82%, PPV of 86%, and NPV of 98%. The combination of BIRADS and VTIQ led to improved test validity. Conclusion. VTIQ is highly reliable and reproducible. There is a significant difference regarding the mean maximum velocity of benign and malignant lesions. Adding VTIQ to BIRADS assessment improves the specificity.

Circulating miRNAs with prognostic value in metastatic breast cancer and for early detection of metastasis

Metastasis is the principal cause of high morbidity and mortality among breast cancer (BC) patients. Identification of markers that can be routinely monitored to predict onset of metastasis in BC patients and prognosis of metastatic breast cancer (MBC) patients would increase their median survival. In this study, plasma miRNAs of 40 MBC patients were profiled by TaqMan low density arrays and miRNAs with prognostic capacity were identified. The candidates were validated initially in the samples of 237 MBC patients and subsequently in 335 samples from an independent study cohort of BC patients. Sixteen miRNAs were established to be significantly associated with overall survival, and were termed as prognostic miRNA panel template (PROMPT). These included miR-141, miR-144, miR-193b, miR-200a, miR-200b, miR-200c, miR-203, miR-210, miR-215, miR-365, miR-375, miR-429, miR-486-5p, miR-801, miR-1260 and miR-1274a. Additionally, 11 of these miRNAs were also associated with progression-free survival. Their prognostic significance was further confirmed in samples from a second study cohort of BC patients. In addition, miR-200a, miR-200b, miR-200c, miR-210, miR-215 and miR-486-5p were found to be significantly associated with onset of metastasis up to 2 years prior to clinical diagnosis in BC patients. We have thus identified panels of miRNAs, which include metastasis promoting miR-200 family and miR-203, as well as oncogenic and tumor-suppressive miRNAs, that can serve as prognostic markers for MBC, and early detection markers of metastasis in BC.

Prevalence of BRCA1/2 germline mutations in 21 401 families with breast and ovarian cancer

Purpose To characterise the prevalence of pathogenic germline mutations in BRCA1 and BRCA2 in families with breast cancer (BC) and ovarian cancer (OC) history. Patients and methods Data from 21 401 families were gathered between 1996 and 2014 in a clinical setting in the German Consortium for Hereditary Breast and Ovarian Cancer, comprising full pedigrees with cancer status of all individual members at the time of first counselling, and BRCA1/2 mutation status of the index patient. Results The overall BRCA1/2 mutation prevalence was 24.0% (95% CI 23.4% to 24.6%). Highest mutation frequencies were observed in families with at least two OCs (41.9%, 95% CI 36.1% to 48.0%) and families with at least one breast and one OC (41.6%, 95% CI 40.3% to 43.0%), followed by male BC with at least one female BC or OC (35.8%; 95% CI 32.2% to 39.6%). In families with a single case of early BC (<36 years), mutations were found in 13.7% (95% CI 11.9% to 15.7%). Postmenopausal unilateral or bilateral BC did not increase the probability of mutation detection. Occurrence of premenopausal BC and OC in the same woman led to higher mutation frequencies compared with the occurrence of these two cancers in different individuals (49.0%; 95% CI 41.0% to 57.0% vs 31.5%; 95% CI 28.0% to 35.2%). Conclusions Our data provide guidance for healthcare professionals and decision-makers to identify individuals who should undergo genetic testing for hereditary breast and ovarian cancer. Moreover, it supports informed decision-making of counselees on the uptake of genetic testing.

Normal breast tissue stiffness measured by a new ultrasound technique: virtual touch tissue imaging quantification (VTIQ).

OBJECTIVE To evaluate normal breast tissue stiffness with virtual touch tissue imaging quantification (VTIQ) using prospectively collected data. MATERIALS AND METHODS B-mode ultrasound and VTIQ were performed in 132 breasts in 97 women. Mean values of VTIQ for parenchyma and fatty tissue were compared between those measured in healthy breasts and in the surrounding of histologically proven benign and malignant breast lesions. Moreover we reviewed VTIQ values according to breast density measured by the American College of Radiology (ACR) categories. In addition we analyzed re-test reliability of VTIQ. RESULTS In 132 breasts the mean VTIQ values in parenchyma were significantly higher than in fatty tissue (3.23 m/s ± 0.74 versus 2.5 m/s ± 0.61; p<0.0001). In healthy breasts as well as in the surrounding of a benign or malignant lesions the VTIQ values of parenchyma were similar (p=0.12). In fatty tissue, small differences between mean VTIQ values of 2.25 m/s ± 0.51, 2.52 m/s ± 0.48 and 2.65 m/s ± 0.71 (p=0.01) in the respective groups were observed. The comparison of mean VTIQ values of parenchyma and fatty tissue in more and less dense breasts (ACR 1+2 versus ACR 3+4 breasts) also yielded no statistically significant difference. The re-test reliability of VTIQ assessed with three independent measurements was moderate (interclass-correlation of 0.52 (p<0.0001)). CONCLUSION VTIQ is a reliable method for measuring the stiffness of breast tissue. We propose standard values for healthy parenchyma and fatty tissues independent of the surrounding tissue or the ACR category.

Change of aesthetic and functional outcome over time and their relationship to quality of life after breast conserving therapy.

PURPOSE We analyzed changes in aesthetic and functional outcome over time after breast conserving therapy. Our special interest resides in the question of whether these aspects gain or loose their influence on quality of life (QoL) with temporal progress. PATIENTS AND METHODS This prospective single centre cohort study included 138 patients, treated with breast conserving surgery and consecutive radiotherapy. Patients completed two questionnaires one week and one year after surgery: the BCTOS (Breast Cancer Treatment Outcome Scale) to measure Functional, Aesthetic, and Breast Sensitivity Status and the EORTC (European Organisation for Research and Treatment of Cancer) C30-BR23 to assess QoL. We applied correlation and multiple regression analysis as statistical methods. RESULTS Aesthetic and Functional Status did not change significantly over one year, whereas Breast Sensitivity Status and several QoL subscales showed significant improvement (p < 0.0001). Correlations between BCTOS scales and EORTC subscales remain similar over time. Functional and Aesthetic Status kept a strong impact on global health (Spearmans Rho = -0.28 to -0.45 depending on time of assessment). Increasing age and poorer Functional Status shortly after surgery are predictors of a decline in global health over one year (p < 0.001). CONCLUSION Functional and aesthetic outcome after breast conserving surgery maintain their impact on QoL over a one year follow-up period and are valuable predictors of QoL.

DNA methylation array analyses identified breast cancer‐associated HYAL2 methylation in peripheral blood

Breast cancer (BC) is the leading cause of cancer‐related mortality in women worldwide. Changes in DNA methylation in peripheral blood could be associated with malignancy at early stage. However, the BC‐associated DNA methylation signatures in peripheral blood were largely unknown. Here, we performed a genome‐wide methylation screening and identified a BC‐associated differentially methylated CpG site cg27091787 in the hyaluronoglucosaminidase 2 gene (HYAL2) (discovery round with 72 BC case and 24 controls: p = 2.61 × 10−9 adjusted for cell‐type proportions). The substantially decreased methylation of cg27091787 in BC cases was confirmed in two validation rounds (first validation round with 338 BC case and 507 controls: p < 0.0001; second validation round with 189 BC case and 189 controls: p < 0.0001). In addition to cg27091787, the decreased methylation of a 650‐bp CpG island shore of HYAL2 was also associated with increased risk of BC. Moreover, the expression and methylation of HYAL2 were inversely correlated with a p‐value of 0.006. To note, the BC‐associated decreased HYAL2 methylation was replicated in the T‐cell fraction (p = 0.034). The cg27091787 methylation level enabled a powerful discrimination of early‐stage BC cases (stages 0 and I) from healthy controls [area under curve (AUC) = 0.89], and was robust for the detection of BC in younger women as well (age < 50, AUC = 0.87). Our study reveals a strong association between decreased HYAL2 methylation in peripheral blood and BC, and provides a promising blood‐based marker for the detection of early BC.

Therapeutic effects of metformin in breast cancer: involvement of the immune system?

Breast cancer and associated diabetes mellitus have gained raising interest as an elevated risk of breast cancer prognosis resulting in increased mortality in diabetic patients. In this context, the long-acting insulin analog glargine and other antidiabetics have been discussed to promote tumorigenesis. In contrast, the biguanide class oral antidiabetic metformin has been shown capable of enhancing cell cycle arrest and inducing apoptosis as well as reducing growth factor signaling. Consequently, several studies are underway to evaluate a possible role of metformin in breast cancer treatment. Although mechanisms involved are not definitely clear yet, here, we discuss metformin’s anticancer effects including the potential impact of the immune system.