To examine global changes in breast heterogeneity across different states, we determined the single‐cell transcriptomes of > 340,000 cells encompassing normal breast, preneoplastic BRCA1+/– tissue, ...the major breast cancer subtypes, and pairs of tumors and involved lymph nodes. Elucidation of the normal breast microenvironment revealed striking changes in the stroma of post‐menopausal women. Single‐cell profiling of 34 treatment‐naive primary tumors, including estrogen receptor (ER)+, HER2+, and triple‐negative breast cancers, revealed comparable diversity among cancer cells and a discrete subset of cycling cells. The transcriptomes of preneoplastic BRCA1+/– tissue versus tumors highlighted global changes in the immune microenvironment. Within the tumor immune landscape, proliferative CD8+ T cells characterized triple‐negative and HER2+ cancers but not ER+ tumors, while all subtypes comprised cycling tumor‐associated macrophages, thus invoking potentially different immunotherapy targets. Copy number analysis of paired ER+ tumors and lymph nodes indicated seeding by genetically distinct clones or mass migration of primary tumor cells into axillary lymph nodes. This large‐scale integration of patient samples provides a high‐resolution map of cell diversity in normal and cancerous human breast.
Synopsis
To examine global changes in breast heterogeneity across different states, this gene expression resource integrates large‐scale patient samples from diverse tissue states and breast cancer subtypes, offering a refined high‐resolution map of cell diversity in the normal and cancerous human mammary gland.
Single‐cell transcriptome analyses profile > 340,000 cells encompassing normal breast, preneoplastic BRCA1+/– tissue, the major breast cancer subtypes, and metastatic lymph nodes.
Pre‐ to post‐menopause transition is associated with marked stromal changes, with decreased PDGFRb and matrix‐associated genes in fibroblasts.
Progression from preneoplasia to tumors correlates with increased immune infiltration in BRCA1 mutation carriers.
Tumor epithelial compartments show comparable diversity in different breast cancer subtypes.
Cycling CD8+ T‐cells are reduced in estrogen receptor (ER)+ tumors, suggesting different immunoregulatory patterns.
Both clonal selection and mass migration contribute to lymph node metastases in patients with ER+ cancer.
A large‐scale gene expression resource integrates diverse tissue samples and reveals unexpected heterogeneity of breast cancer subtypes.
Individuals who have mutations in the breast-cancer-susceptibility gene BRCA1 (hereafter referred to as BRCA1-mutation carriers) frequently undergo prophylactic mastectomy to minimize their risk of ...breast cancer. The identification of an effective prevention therapy therefore remains a 'holy grail' for the field. Precancerous BRCA1(mut/+) tissue harbors an aberrant population of luminal progenitor cells, and deregulated progesterone signaling has been implicated in BRCA1-associated oncogenesis. Coupled with the findings that tumor necrosis factor superfamily member 11 (TNFSF11; also known as RANKL) is a key paracrine effector of progesterone signaling and that RANKL and its receptor TNFRSF11A (also known as RANK) contribute to mammary tumorigenesis, we investigated a role for this pathway in the pre-neoplastic phase of BRCA1-mutation carriers. We identified two subsets of luminal progenitors (RANK(+) and RANK(-)) in histologically normal tissue of BRCA1-mutation carriers and showed that RANK(+) cells are highly proliferative, have grossly aberrant DNA repair and bear a molecular signature similar to that of basal-like breast cancer. These data suggest that RANK(+) and not RANK(-) progenitors are a key target population in these women. Inhibition of RANKL signaling by treatment with denosumab in three-dimensional breast organoids derived from pre-neoplastic BRCA1(mut/+) tissue attenuated progesterone-induced proliferation. Notably, proliferation was markedly reduced in breast biopsies from BRCA1-mutation carriers who were treated with denosumab. Furthermore, inhibition of RANKL in a Brca1-deficient mouse model substantially curtailed mammary tumorigenesis. Taken together, these findings identify a targetable pathway in a putative cell-of-origin population in BRCA1-mutation carriers and implicate RANKL blockade as a promising strategy in the prevention of breast cancer.
Background
Magseed technology is a recently introduced localisation technique for impalpable breast lesions with possible advantages over traditional techniques. These include improved theatre ...logistics, flexibility in incision placement and improved patient experience. This multicentre study evaluates the experience of introducing Magseed technology into routine surgical practice.
Methods
A prospective multicentre study of Magseed localised procedures was performed. Insertion data were recorded by the radiologist including lesion characteristics and Magseed insertion accuracy. The surgical team recorded time from insertion to operation, operating time and surgical satisfaction. Pathology results were reviewed for specimen weight and margins.
Results
Between February 2019 and June 2020, 100 patients were enrolled. Magseed localised procedures included 18 excisional biopsies, 23 wide local excisions (WLE), 50 WLE with axillary surgery and four cases of Magseed localised breast WLE with Magseed localised axillary surgery. There were three therapeutic mammoplasties and two cases of Magseed localised targeted axillary node dissection alone. A total of 90% of Magseeds were radiologically placed within 5 mm of the target lesion/node. Time between incision and specimen removal was 17 min (range 6–40 min). All breast and axillary Magseeds were successfully identified and retrieved during surgery. The target lesion was identified in the specimen in all cases. A total of 10% of cases required further surgery for pathologically positive margins. Overall, surgeons reported that Magseed localisation was “easy” or “very easy” in 77% of cases.
Conclusion
Magseed is a reliable, safe and accurate surgical technique that provides logistical advantages and flexibility of surgical approach. The method was well‐accepted by all users.
Magseed localisation of non‐palpable breast lesion.
Magseed localisation of non‐palpable breast lesion.
Several studies over the past two decades have presented varying degrees of evidence that an increased motive to serve the public good is prevalent in the public sector workforce. A widely accepted ...and measurable construct for public service motivation could have ramifications for public personnel managers in a number of key areas. This paper reviews the current literature on public service motivation (PSM) theory and examines how this desire to make a difference might e harnessed as a motivational force for human resource managers. The prevalence of PSM in the nonprofit sector is also explored as a means of broadening the current public-private dichotomy.
iPrevent estimates breast cancer (BC) risk and provides tailored risk management information.
The objective of this study was to assess the usability and acceptability of the iPrevent prototype.
...Clinicians were eligible for participation in the study if they worked in primary care, breast surgery, or genetics clinics. Female patients aged 18-70 years with no personal cancer history were eligible. Clinicians were first familiarized with iPrevent using hypothetical paper-based cases and then actor scenarios; subsequently, they used iPrevent with their patients. Clinicians and patients completed the System Usability Scale (SUS) and an Acceptability questionnaire 2 weeks after using iPrevent; patients also completed measures of BC worry, anxiety, risk perception, and knowledge pre- and 2 weeks post-iPrevent. Data were summarized using descriptive statistics.
The SUS and Acceptability questionnaires were completed by 19 of 20 clinicians and 37 of 43 patients. Usability was above average (SUS score >68) for 68% (13/19) clinicians and 76% (28/37) patients. The amount of information provided by iPrevent was reported as "about right" by 89% (17/19) clinicians and 89% (33/37) patients and 95% (18/19) and 97% (36/37), respectively, would recommend iPrevent to others, although 53% (10/19) clinicians and 27% (10/37) patients found it too long. Exploratory analyses suggested that iPrevent could improve risk perception, decrease frequency of BC worry, and enhance BC prevention knowledge without changing state anxiety.
The iPrevent prototype demonstrated good usability and acceptability. Because concerns about length could be an implementation barrier, data entry has been abbreviated in the publicly available version of iPrevent.
Summary
Measuring changes in protein or organelle abundance in the cell is an essential, but challenging aspect of cell biology. Frequently‐used methods for determining organelle abundance typically ...rely on detection of a very few marker proteins, so are unsatisfactory. In silico estimates of protein abundances from publicly available protein spectra can provide useful standard abundance values but contain only data from tissue proteomes, and are not coupled to organelle localization data. A new protein abundance score, the normalized protein abundance scale (NPAS), expands on the number of scored proteins and the scoring accuracy of lower‐abundance proteins in Arabidopsis. NPAS was combined with subcellular protein localization data, facilitating quantitative estimations of organelle abundance during routine experimental procedures. A suite of targeted proteomics markers for subcellular compartment markers was developed, enabling independent verification of in silico estimates for relative organelle abundance. Estimation of relative organelle abundance was found to be reproducible and consistent over a range of tissues and growth conditions. In silico abundance estimations and localization data have been combined into an online tool, multiple marker abundance profiling, available in the SUBA4 toolbox (http://suba.live).
Significance Statement
Accurately determining the subcellular composition of complex samples is difficult, especially as organelle proteomes change in response to their environment. Here we improve the speed and accuracy of subcellular analyses by developing methods which bridge the gap between the analytical benefits of mass spectrometry and its wider availability within the Arabidopsis research community, and present a template for development in other species.
There is a growing interest in delivering more personalised, risk-based breast cancer screening protocols. This requires population-level validation of practical models that can stratify women into ...breast cancer risk groups. Few studies have evaluated the Gail model (NCI Breast Cancer Risk Assessment Tool) in a population screening setting; we validated this tool in a large, screened population.
We used data from 40,158 women aged 50-69 years (via the lifepool cohort) participating in Australia's BreastScreen programme. We investigated the association between Gail scores and future invasive breast cancer, comparing observed and expected outcomes by Gail score ranked groups. We also used machine learning to rank Gail model input variables by importance and then assessed the incremental benefit in risk prediction obtained by adding variables in order of diminishing importance.
Over a median of 4.3 years, the Gail model predicted 612 invasive breast cancers compared with 564 observed cancers (expected/observed (E/O) = 1.09, 95% confidence interval (CI) 1.00-1.18). There was good agreement across decile groups of Gail scores (χ
= 7.1, p = 0.6) although there was some overestimation of cancer risk in the top decile of our study group (E/O = 1.65, 95% CI 1.33-2.07). Women in the highest quintile (Q5) of Gail scores had a 2.28-fold increased risk of breast cancer (95% CI 1.73-3.02, p < 0.0001) compared with the lowest quintile (Q1). Compared with the median quintile, women in Q5 had a 34% increased risk (95% CI 1.06-1.70, p = 0.014) and those in Q1 had a 41% reduced risk (95% CI 0.44-0.79, p < 0.0001). Similar patterns were observed separately for women aged 50-59 and 60-69 years. The model's overall discrimination was modest (area under the curve (AUC) 0.59, 95% CI 0.56-0.61). A reduced Gail model excluding information on ethnicity and hyperplasia was comparable to the full Gail model in terms of correctly stratifying women into risk groups.
This study confirms that the Gail model (or a reduced model excluding information on hyperplasia and ethnicity) can effectively stratify a screened population aged 50-69 years according to the risk of future invasive breast cancer. This information has the potential to enable more personalised, risk-based screening strategies that aim to improve the balance of the benefits and harms of screening.
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