A Single-Cell Atlas of the Tumor and Immune Ecosystem of Human Breast Cancer.

Breast cancer is a heterogeneous disease. Tumor cells and associated healthy cells form ecosystems that determine disease progression and response to therapy. To characterize features of breast cancer ecosystems and their associations with clinical data, we analyzed 144 human breast tumor and 50 non-tumor tissue samples using mass cytometry. The expression of 73 proteins in 26 million cells was evaluated using tumor and immune cell-centric antibody panels. Tumors displayed individuality in tumor cell composition, including phenotypic abnormalities and phenotype dominance. Relationship analyses between tumor and immune cells revealed characteristics of ecosystems related to immunosuppression and poor prognosis. High frequencies of PD-L1+ tumor-associated macrophages and exhausted T cells were found in high-grade ER+ and ER- tumors. This large-scale, single-cell atlas deepens our understanding of breast tumor ecosystems and suggests that ecosystem-based patient classification will facilitate identification of individuals for precision medicine approaches targeting the tumor and its immunoenvironment.

Impact of molecular subtypes on the prediction of distant recurrence in estrogen receptor (ER) positive, human epidermal growth factor receptor 2 (HER2) negative breast cancer upon five years of endocrine therapy.

BACKGROUND: Current evidence suggests that patients with Luminal A early breast cancer can skip chemotherapy or extended endocrine therapy, but immunohistochemistry-based biomarker analysis for St Gallen subtyping may not be reproducible. We asked whether RT-qPCR can be used instead to address this clinical question. METHODS: RNA was extracted from tumor material derived from ER+/HER2- patients receiving adjuvant endocrine treatment for low-risk cancers and was semi-quantified by RT-qPCR with the MammaTyper®. St Gallen subtypes were based on the mRNA expression of ERBB2/HER2, ESR1/ER, PGR/PR and MKI67/Ki67 after dichotomizing at predefined cut-offs. Differences in distant disease-free survival (DDFS) were assessed by Kaplan Meier analysis and Cox regression. RESULTS: With a median follow up of 7.8 years, there were ten events in the group of 195 Luminal A-like tumors (5.1%) and 18 events in the remaining 127 tumors (14.1%), consisting mostly of Luminal B-like cases (N = 119). Luminal A-like had significantly better DDFS over the entire follow-up period (HR 0.35, 95% CIs 0.16-0.76, p = 0.0078) with a trend towards reduced probability of recurrences also in the late phase (> 5 years) (HR 0.20, p = 0.052). The survival advantage spanning the entire follow-up period persisted in the pN0 or pN0-N1 subgroups or after correcting for clinicopathological parameters. MKI67 alone significantly predicted for worse DDFS (HR 2.62, 95% CIs 1.24-5.56, p = 0.0088). CONCLUSIONS: St Gallen Luminal A-like tumors identified by RT-qPCR display markedly low rates of distant recurrence at ten years follow-up. Patients with such tumors could be spared chemotherapy due to the obviously unfavourable benefit/toxicity ratio.

AKT1 (E17K) mutation profiling in breast cancer: prevalence, concurrent oncogenic alterations, and blood-based detection.

BACKGROUND: The single hotspot mutation AKT1 [G49A:E17K] has been described in several cancers, with the highest incidence observed in breast cancer. However, its precise role in disease etiology remains unknown. METHODS: We analyzed more than 600 breast cancer tumor samples and circulating tumor DNA for AKT1 (E17K) and alterations in other cancer-associated genes using Beads, Emulsions, Amplification, and Magnetics digital polymerase chain reaction technology and targeted exome sequencing. RESULTS: Overall AKT1 (E17K) mutation prevalence was 6.3 % and not correlated with age or menopausal stage. AKT1 (E17K) mutation frequency tended to be lower in patients with grade 3 disease (1.9 %) compared with those with grade 1 (11.1 %) or grade 2 (6 %) disease. In two cohorts of patients with advanced metastatic disease, 98.0 % (n = 50) and 97.1 % (n = 35) concordance was obtained between tissue and blood samples for the AKT1 (E17K) mutation, and mutation capture rates of 66.7 % (2/3) and 85.7 % (6/7) in blood versus tissue samples were observed. Although AKT1-mutant tumor specimens were often found to harbor concurrent alterations in other driver genes, a subset of specimens harboring AKT1 (E17K) as the only known driver alteration was also identified. Initial follow-up survival data suggest that AKT1 (E17K) could be associated with increased mortality. These findings warrant additional long-term follow-up. CONCLUSIONS: The data suggest that AKT1 (E17K) is the most likely disease driver in certain breast cancer patients. Blood-based mutation detection is achievable in advanced-stage disease. These findings underpin the need for a further enhanced-precision medicine paradigm in the treatment of breast cancer.

Promoter hypermethylation of the tumor-suppressor genes ITIH5, DKK3, and RASSF1A as novel biomarkers for blood-based breast cancer screening.

INTRODUCTION: For early detection of breast cancer, the development of robust blood-based biomarkers that accurately reflect the host tumor is mandatory. We investigated DNA methylation in circulating free DNA (cfDNA) from blood of breast cancer patients and matched controls to establish a biomarker panel potentially useful for early detection of breast cancer. METHODS: We examined promoter methylation of seven putative tumor-suppressor genes (SFRP1, SFRP2, SFRP5, ITIH5, WIF1, DKK3, and RASSF1A) in cfDNA extracted from serum. Clinical performance was first determined in a test set (n = 261 sera). In an independent validation set (n = 343 sera), we validated the most promising genes for further use in early breast cancer detection. Sera from 59 benign breast disease and 58 colon cancer patients were included for additional specificity testing. RESULTS: Based on the test set, we determined ITIH5 and DKK3 promoter methylation as candidate biomarkers with the best sensitivity and specificity. In both the test and validation set combined, ITIH5 and DKK3 methylation achieved 41% sensitivity with a specificity of 93% and 100% in healthy and benign disease controls, respectively. Combination of these genes with RASSF1A methylation increased the sensitivity to 67% with a specificity of 69% and 82% in healthy controls and benign disease controls, respectively. CONCLUSIONS: Tumor-specific methylation of the three-gene panel (ITIH5, DKK3, and RASSF1A) might be a valuable biomarker for the early detection of breast cancer.

Cancer-associated fibroblast classification in single-cell and spatial proteomics data.

Cancer-associated fibroblasts (CAFs) are a diverse cell population within the tumour microenvironment, where they have critical effects on tumour evolution and patient prognosis. To define CAF phenotypes, we analyse a single-cell RNA sequencing (scRNA-seq) dataset of over 16,000 stromal cells from tumours of 14 breast cancer patients, based on which we define and functionally annotate nine CAF phenotypes and one class of pericytes. We validate this classification system in four additional cancer types and use highly multiplexed imaging mass cytometry on matched breast cancer samples to confirm our defined CAF phenotypes at the protein level and to analyse their spatial distribution within tumours. This general CAF classification scheme will allow comparison of CAF phenotypes across studies, facilitate analysis of their functional roles, and potentially guide development of new treatment strategies in the future.

A comprehensive single-cell map of T cell exhaustion-associated immune environments in human breast cancer.

Immune checkpoint therapy in breast cancer remains restricted to triple negative patients, and long-term clinical benefit is rare. The primary aim of immune checkpoint blockade is to prevent or reverse exhausted T cell states, but T cell exhaustion in breast tumors is not well understood. Here, we use single-cell transcriptomics combined with imaging mass cytometry to systematically study immune environments of human breast tumors that either do or do not contain exhausted T cells, with a focus on luminal subtypes. We find that the presence of a PD-1high exhaustion-like T cell phenotype is associated with an inflammatory immune environment with a characteristic cytotoxic profile, increased myeloid cell activation, evidence for elevated immunomodulatory, chemotactic, and cytokine signaling, and accumulation of natural killer T cells. Tumors harboring exhausted-like T cells show increased expression of MHC-I on tumor cells and of CXCL13 on T cells, as well as altered spatial organization with more immature rather than mature tertiary lymphoid structures. Our data reveal fundamental differences between immune environments with and without exhausted T cells within luminal breast cancer, and show that expression of PD-1 and CXCL13 on T cells, and MHC-I - but not PD-L1 - on tumor cells are strong distinguishing features between these environments.

Compared DNA and RNA quality of breast cancer biobanking samples after long-term storage protocols in - 80 °C and liquid nitrogen.

Molecular investigations are crucial for further developments in precision medicine. RNA sequencing, alone or in combination with further omic-analyses, resulted in new therapeutic strategies. In this context, biobanks represent infrastructures to store tissue samples and body fluids in combination with clinical data to promote research for new predictive and prognostic biomarkers as well as therapeutic candidate molecules. Until today, the optimal storage conditions are a matter of debate especially with view to the storage temperature. In this unique approach we compared parallel samples from the same tumour, one half stored at - 80 °C and one half in the vapor phase of liquid nitrogen, with almost identical pre-analytical conditions. We demonstrated that RNA isolated from breast cancer samples revealed significantly higher RINe-values after 10 years of storage in the vapor phase of liquid nitrogen compared to storage at - 80 °C. In contrast, no significant difference was found regarding the DIN-values after DNA isolation. Morphological changes of the nucleus and cytoplasm, especially in the samples stored at - 80 °C, gave insights to degenerative effects, most possibly due to the storage protocol and its respective peculiarities. In addition, our results indicate that exact point-to point documentation beginning at the sample preparation is mandatory.

Chromothripsis in Human Breast Cancer.

Chromothripsis is a form of genome instability by which a presumably single catastrophic event generates extensive genomic rearrangements of one or a few chromosomes. Widely assumed to be an early event in tumor development, this phenomenon plays a prominent role in tumor onset. In this study, an analysis of chromothripsis in 252 human breast cancers from two patient cohorts (149 metastatic breast cancers, 63 untreated primary tumors, 29 local relapses, and 11 longitudinal pairs) using whole-genome and whole-exome sequencing reveals that chromothripsis affects a substantial proportion of human breast cancers, with a prevalence over 60% in a cohort of metastatic cases and 25% in a cohort comprising predominantly luminal breast cancers. In the vast majority of cases, multiple chromosomes per tumor were affected, with most chromothriptic events on chromosomes 11 and 17 including, among other significantly altered drivers, CCND1, ERBB2, CDK12, and BRCA1. Importantly, chromothripsis generated recurrent fusions that drove tumor development. Chromothripsis-related rearrangements were linked with univocal mutational signatures, with clusters of point mutations due to kataegis in close proximity to the genomic breakpoints and with the activation of specific signaling pathways. Analyzing the temporal order of events in tumors with and without chromothripsis as well as longitudinal analysis of chromothriptic patterns in tumor pairs offered important insights into the role of chromothriptic chromosomes in tumor evolution. SIGNIFICANCE: These findings identify chromothripsis as a major driving event in human breast cancer.

Correction: SNiPER: a novel hypermethylation biomarker panel for liquid biopsy based early breast cancer detection.

[This corrects the article DOI: 10.18632/oncotarget.27303.].

SNiPER: a novel hypermethylation biomarker panel for liquid biopsy based early breast cancer detection.

INTRODUCTION: Mammography is the gold standard for early breast cancer detection, but shows important limitations. Blood-based approaches on basis of cell-free DNA (cfDNA) provide minimally invasive screening tools to characterize epigenetic alterations of tumor suppressor genes and could serve as a liquid biopsy, complementing mammography. METHODS: Potential biomarkers were identified from The Cancer Genome Atlas (TCGA), using HumanMethylation450-BeadChip data. Promoter methylation status was evaluated quantitatively by pyrosequencing in a serum test cohort (n = 103), a serum validation cohort (n = 368) and a plasma cohort (n = 125). RESULTS: SPAG6, NKX2-6 and PER1 were identified as novel biomarker candidates. ITIH5 was included on basis of our previous work. In the serum test cohort, a panel of SPAG6 and ITIH5 showed 63% sensitivity for DCIS and 51% sensitivity for early invasive tumor (pT1, pN0) detection at 80% specificity. The serum validation cohort revealed 50% sensitivity for DCIS detection on basis of NKX2-6 and ITIH5. Furthermore, an inverse correlation between methylation frequency and cfDNA concentration was uncovered. Therefore, markers were tested in a plasma cohort, achieving a 64% sensitivity for breast cancer detection using SPAG6, PER1 and ITIH5. CONCLUSIONS: Although liquid biopsy remains challenging, a combination of SPAG6, NKX2-6, ITIH5 and PER1 (SNiPER) provides a promising tool for blood-based breast cancer detection.

Superficial radiation therapy in peyronie's disease: An effective and well-tolerated therapy.

PURPOSE: This study aimed to assess the safety, efficacy, and patient satisfaction of superficial radiation therapy in the treatment of Peyronie's disease (PD) in a retrospective analysis. METHODS AND MATERIALS: We performed a retrospective analysis of 83 patients who underwent radiation therapy between 1999 and 2008 with 8 fractions of 4 Gy over a period of 6 months. With a mean follow-up time of 52 months, patients responded to a comprehensive questionnaire that covered patient characteristics, disease duration before radiation therapy, course of disease, treatment response, side effects, and patient satisfaction. RESULTS: After a mean follow-up time of 52 months, 78% of the treated patients reported that PD progression had stopped. Furthermore 47% of patients had a symptom regression. Only 7% of patients reported PD progression. The penile curvature was improved in 49% of patients, and plaque induration could be reduced in 42% of patients. Moreover, 71% of patients reported substantial pain relief, as measured by a visual analogue scale (1 = not satisfied; 10 = very satisfied). Treatment satisfaction was rated with a median of 8 in a visual analogue scale out of 10. Side effects included transient erythema in 38.6% of patients and 9.6% reported of transient or chronic dryness. No severe side effects were observed. CONCLUSIONS: Radiation therapy for PD in the disease's early stages proved to be a safe and well-tolerated method with good results in pain relief, especially in patients aged <62 years. No serious adverse events or malign transformations are expected using doses up to 32 Gy.

The Treatment of Primary Breast Cancer in Older Women With Adjuvant Therapy: A Retrospective Analysis of Data From Over 3000 Patients From the PATH Biobank, With Two-Year Follow-up.

BACKGROUND: Breast cancer is the most common cancer in women in Germany. Mortality from breast cancer has declined over the past 15 years, but less so in women aged 70 or older than in younger women. The discrepancy might be explained by age-related differences in treatment. METHODS: Data from the Patients' Tumor Bank of Hope (PATH) database of women who underwent adjuvant treatment for the treatment of an invasive primary tumor without distant metastases (year of diagnosis, 2006-2011) were retrospectively analyzed. The clinical and tumor-biological findings and treatment data over two years of follow-up were compared across three age groups (under age 50, ages 50 to 69, and ages 70 and up). Chi-square tests were carried out to reveal significant differences, and post-hoc multiple comparisons were performed with and without Bonferroni correction. Treatment data were adjusted for staging and grading and tested for age-dependence with logistic regression. RESULTS: Follow-up data were available for 3257 (65% ) of 4981 women, of whom 61% were in the middle age group and 22% in the oldest. Compared to women aged 50 to 69, those aged 70 and up less commonly received breast-conserving treatment (68.8% vs. 86.4% ), chemotherapy (27.5% vs. 44.1% ), radiotherapy (81.8% vs. 92.4% ), and trastuzumab (52.9% vs. 79.3% ; p<0.001 for all differences). All differences remained significant after stastistical adjustment. CONCLUSION: The cause of these age-related differences is unclear. It cannot be determined from these data whether concomitant disease, the older patients' individual decisions, or other factors were responsible for their not receiving treatment as often as the younger patients did.

Reprogramming of the ERRα and ERα target gene landscape triggers tamoxifen resistance in breast cancer.

Endocrine treatment regimens for breast cancer that target the estrogen receptor-α (ERα) are effective, but acquired resistance remains a limiting drawback. One mechanism of acquired resistance that has been hypothesized is functional substitution of the orphan receptor estrogen-related receptor-α (ERRα) for ERα. To examine this hypothesis, we analyzed ERRα and ERα in recurrent tamoxifen-resistant breast tumors and conducted a genome-wide target gene profiling analysis of MCF-7 breast cancer cell populations that were sensitive or resistant to tamoxifen treatment. This analysis uncovered a global redirection in the target genes controlled by ERα, ERRα, and their coactivator AIB1, defining a novel set of target genes in tamoxifen-resistant cells. Beyond differences in the ERα and ERRα target gene repertoires, both factors were engaged in similar pathobiologic processes relevant to acquired resistance. Functional analyses confirmed a requirement for ERRα in tamoxifen- and fulvestrant-resistant MCF-7 cells, with pharmacologic inhibition of ERRα sufficient to partly restore sensitivity to antiestrogens. In clinical specimens (n = 1041), increased expression of ERRα was associated with enhanced proliferation and aggressive disease parameters, including increased levels of p53 in ERα-positive cases. In addition, increased ERRα expression was linked to reduced overall survival in independent tamoxifen-treated patient cohorts. Taken together, our results suggest that ERα and ERRα cooperate to promote endocrine resistance, and they provide a rationale for the exploration of ERRα as a candidate drug target to treat endocrine-resistant breast cancer.

AGR3 in breast cancer: prognostic impact and suitable serum-based biomarker for early cancer detection.

Blood-based early detection of breast cancer has recently gained novel momentum, as liquid biopsy diagnostics is a fast emerging field. In this study, we aimed to identify secreted proteins which are up-regulated both in tumour tissue and serum samples of breast cancer patients compared to normal tissue and sera. Based on two independent tissue cohorts (n = 75 and n = 229) and one serum cohort (n = 80) of human breast cancer and healthy serum samples, we characterised AGR3 as a novel potential biomarker both for breast cancer prognosis and early breast cancer detection from blood. AGR3 expression in breast tumours is significantly associated with oestrogen receptor α (P<0.001) and lower tumour grade (P<0.01). Interestingly, AGR3 protein expression correlates with unfavourable outcome in low (G1) and intermediate (G2) grade breast tumours (multivariate hazard ratio: 2.186, 95% CI: 1.008-4.740, P<0.05) indicating an independent prognostic impact. In sera analysed by ELISA technique, AGR3 protein concentration was significantly (P<0.001) elevated in samples from breast cancer patients (n = 40, mainly low stage tumours) compared to healthy controls (n = 40). To develop a suitable biomarker panel for early breast cancer detection, we measured AGR2 protein in human serum samples in parallel. The combined AGR3/AGR2 biomarker panel achieved a sensitivity of 64.5% and a specificity of 89.5% as shown by receiver operating characteristic (ROC) curve statistics. Thus our data clearly show the potential usability of AGR3 and AGR2 as biomarkers for blood-based early detection of human breast cancer.

Comparison of MammaPrint and TargetPrint results with clinical parameters in German patients with early stage breast cancer.

The 70-gene expression profile MammaPrint is a powerful prognostic indicator for disease outcome in breast cancer patients with improved prediction of recurrence risk compared to currently used guidelines. The microarray-based test TargetPrint further provides reliable, quantitative assessment of mRNA expression levels of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2). This study was performed as a validation of MammaPrint and TargetPrint in an unselected German breast cancer population and was designed to determine the degree of concordance with currently applied clinical parameters. One hundred and forty cases of breast cancer stage I and II were classified as being low or high risk for distant metastasis using MammaPrint. Results were compared to current clinical risk classifications and adjuvant treatment management. Immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH)/chromogenic in situ hybridization (CISH) assessments of ER, PR and HER2 were further compared with gene expression read-outs using TargetPrint. Thirty-two percent of patients (19/59) with a poor prognosis-signature identified via MammaPrint did not receive adjuvant systemic treatment apart from endocrine therapy and were potentially undertreated; whereas 42% (35/77) of patients with a good prognosis-signature received chemotherapy and were potentially overtreated. Comparison of microarray receptor results with IHC and FISH/CISH were concordant in 97% for ER; 86% for PR; and 94% for HER2. In this German study population, MammaPrint would have resulted in altered treatment advice for adjuvant systemic therapy in 40% of patients. Furthermore, TargetPrint presented high concordance for ER, PR and Her2 with IHC and FISH/CISH analysis.