The prognostic significance of BMI1 expression in invasive breast cancer is dependent on its molecular subtypes

Purpose: BMI-1, which is a major component of the polycomb groupcomplex 1 is an essential epigenetic repressor of multiple regulatory genes and has been identified as a cancer stem cell (CSC) marker in several cancers. However, its role in breast cancer (BC) remains to be defined. In this study, we have evaluated the prognostic significance of BMI-1 among the different molecular subtypes and assessed its association with other breast CSC markers (BCSC).Material and Method: BMI-1 copy number and mRNA was assessed in large and well-characterised cohorts of early-stage BC patients [METABRIC (n=1980) and the Bc-GenExMiner (n=9616) databases]. BMI-1 protein expression was assessed using tissue microarray and immunohistochemistry in a cohort of 870 invasive BC patients with long- term outcome data and the expression of a panel of BCSC markers was monitored.Result: BMI-1 expression, prognostic significance and its association with BCSC markers were differed between molecular classes. In the luminal oestrogen receptor positive (ER+) BC, BMI-1 showed significantly higher expression compared to ER- tumours. BMI-1 showed positive correlation with favourable prognostic features and it was negatively associated with the expression of key BCSC markers (ALDH1A1, CD24, CD44, CD133, SOX10 and SOX9). High expression of BMI-1 was associated with longer breast cancer specific survival (BCSS) independent of other prognostic variables. In the basal triple negative BC subtype, BMI-1 expression showed positive association with CD133 and SOX10 and it was significantly associated with shorter BCSS.Conclusion: High variables and outcome in BC. However, this association is dependent on the molecular subtypes. Further functional assessment to detect its underlying mechanistic roles in BC subtypes is warranted

The prognostic significance of ALDH1A1 expression in early invasive breast cancer

Aims: Aldehyde dehydrogenase family 1 member A1 (ALDH1A1)is reportedly a key ALDH isozyme linked to the cancer stem cells (CSC) of many solid tumours, where it is involved in self-renewal, differentiation and self-protection. In this study, the prognostic significance of ALDH1A1 expression in early invasive breast cancer (BC) and its role as a BC stem cell (BCSC) were evaluated.Methods: ALDH1A1 expression was assessed, using immunohistochemistry and tissue microarrays, in a large well- characterised BC cohort. ALDH1A1 mRNA expression was also assessed at the transcriptomic levels, utilising data from the Molecular Taxonomy of Breast Cancer International Consortium. The associations of ALDH1A1 with clinicopathological parameters, other stem cell markers and patient outcomes were determined.Results: ALDH1A1 was expressed in 71% of BC cases, at both the protein and mRNA levels. High ALDH1A1 expression was associated with poor prognostic features, including high grade, poor Nottingham Prognostic Index (NPI), lymph node metastasis and highly proliferative ER+ (luminal B) and triple negative (TNBC) subtypes. ALDH1A1 expression was positively correlated with the expression of CD44, CD24, TWIST, SOX9, EPCAM and CD133. The high immunoexpression of ALDH1A1 was significantly associated with poor BC-specific survival [less than] 0.001), and specifically in the luminal B and TNBC subtypes (P=0.042 and P=0.003, respectively). The immunoexpression of ALDH1A1 was an independent predictor of poor prognosis (P=0.015).Conclusions: ALDH1A1, as assessed using IHC, seems to act as a BCSC marker associated not only with other BCSC markers but also with poor prognostic characteristics and poor outcomes, particularly in the luminal B and TNBC subtypes

Cten promotes Epithelial–Mesenchymal Transition (EMT) in colorectal cancer through stabilisation of Src

Cten is an oncogene promoting EMT in many signaling pathways, namely through Snail. We investigated whether Cten function could be mediated through Src. Cten levels were modulated by forced expression in HCT116 and gene knockdown in SW620 CRC (colorectal cancer) cell lines. In all cell lines, Cten was a positive regulator of Src expression. The functional importance of Src was tested by simultaneous Cten overexpression and Src knockdown. This resulted in abrogation of Cten motility-inducing activity and reduction of colony formation ability together with failure to induce Cten targets. In SW620ΔCten reduced Src expression increased following restoration of Cten, also leading to increased cell motility and colony formation, which were lost if Src was concomitantly knocked down. By qRT-PCR we showed modulation of Cten had no effect on Src mRNA. However, a CHX pulse chase assay demonstrated stabilization of Src protein by Cten. Finally, expression of Cten and Src was tested in a series of 84 primary CRCs and there was a significant correlation between them (P = 0.001). We conclude that Src is a novel and functionally important target of the Cten signaling pathway and that Cten protein causes post-transcriptional stabilization of Src in promoting EMT and possibly metastasis in CRC

The clinical significance of cyclin B1 (CCNB1) in invasive breast cancer with emphasis on its contribution to lymphovascular invasion development

BackgroundLymphovascular invasion (LVI) is regulated through complex molecular mechanisms. Cyclin B1 (CCNB1) was previously determined as being associated with LVI using large cohorts of breast cancer (BC) and artificial neural network (ANN) technique. In this study, we aimed to assess the association between CCNB1 and LVI, other clinicopathological and other LVI-related biomarkers at the molecular (RNA transcriptomic) and proteomic levels in BC.MethodsTwo transcriptomic BC cohorts (n = 2834) were used to assess the association between the expression of CCNB1 at the mRNA level and clinicopathological characteristics and patient outcome. Tissue microarrays (TMAs) from a well-characterised BC cohort (n = 2480) with long-term outcome were also used to assess the clinical significance of CCNB1 protein expression using immunohistochemistry.ResultsHigh CCNB1 mRNA expression was associated with aggressive tumour behaviour, including LVI, larger size, higher tumour grade, high lymph nodal stage, hormonal receptor negativity, HER2 positivity and poor clinical outcome (all p < 0.0001). Similarly, high CCNB1 protein expression was associated with higher tumour grade, hormonal receptor negativity and HER2 positivity (all p < 0.0001). Additionally, there was a significant association between CCNB1- and LVI-related biomarkers including N-cadherin, P-cadherin and TWIST2 at the transcriptomic and proteomic level. Multivariate analysis revealed that CCNB1 was an independent predictor of shorter BC-specific survival (HR = 1.3; 95% CI 1.2–1.5; p = 0.010).ConclusionCCNB1 is a key gene associated with LVI in BC and has prognostic value. More functional studies are warranted to unravel the mechanistic role of CCNB1 in the development of LVI

The clinical and biological significance of HER2 over-expression in breast ductal carcinoma in situ: a large study from a single institution

© 2019, Cancer Research UK. Background: Previous studies have reported up to 50% of ductal carcinoma in situ (DCIS), is HER2 positive, but the frequency of HER2-positive invasive breast cancer (IBC) is lower. The aim of this study is to characterise HER2 status in DCIS and assess its prognostic value. Methods: HER2 status was evaluated in a large series of DCIS (n = 868), including pure DCIS and DCIS associated with IBC, prepared as tissue microarrays (TMAs). HER2 status was assessed using immunohistochemistry (IHC) and chromogenic in situ hybridisation (CISH). Results: In pure DCIS, HER2 protein was over-expressed in 9% of DCIS (3+), whereas 15% were HER2 equivocal (2+). Using CISH, the final HER2 status was positive in 20%. In mixed DCIS, HER2 amplification of the DCIS component was detected in 15% with amplification in the invasive component of only 12%. HER2-positive DCIS was associated with features of aggressiveness (p < 0.0001) and more frequent local recurrence (p = 0.03). On multivariate analysis, combined HER2+/Ki67+ profile was an independent predictor of local recurrence (p = 0.006). Conclusions: The frequency of HER2 positivity in DCIS is comparable to IBC- and HER2-positive DCIS is associated with features of poor prognosis. The majority of HER2 over-expression in DCIS is driven by gene amplification

Surgical management of ductal carcinoma in situ of the breast: A large retrospective study from a single institution

Background: Management of breast ductal carcinoma in situ (DCIS) has various approaches with distinct institutional specific practice. Here, we review DCIS management in a single institution with emphasise on re-operation rates and outcome. Methods: DCIS cases diagnosed at the Nottingham Breast Institute between 1987 and 2017 were identified (n=1,249). Clinicopathological data was collected. Cases were histologically reviewed, and different factors associated with primary operation selection, re-excision, presence of residual tumour in the re-excision specimens, use of radiotherapy and ipsilateral recurrences were analysed. Results: 34% of DCIS patients were initially treated by mastectomy and were more frequently symptomatic, of high nuclear tumour grade, size >40mm, and associated with comedo necrosis and Paget’s disease of the nipple. Further surgery was due to involved or narrow surgical margins. Residual tumour tissue was detected in 53% of the re-excision specimens. Re-excision rates of patients treated with breast conserving surgery (BCS) were reduced from approximately 70% to 23% and the final mastectomy rates decreased from 60% to 20%. Changes in surgical practice with acceptance of smaller excision margins and more frequent use of local radiotherapy have led to a significant decrease not only in the re-excision rate but also in the final mastectomy rate together with non-significant reduction in 5- and 10-year local recurrence rates. Conclusion: Although BCS is increasingly the preferred primary surgical option for DCIS management, a proportion of low-risk DCIS patients continue to undergo re-excision surgery or completion mastectomy. Despite acceptance of smaller margins, recurrence rate is decreasing

CDC20 expression in oestrogen receptor positive breast cancer predicts poor prognosis and lack of response to endocrine therapy

PurposeEndocrine therapy is the standard treatment for oestrogen receptor positive (ER+) breast cancer. Despite its efficacy, around half of patients will develop resistance to this treatment and eventually relapse. Identification of effective and reliable biomarkers to predict the efficacy of endocrine therapy is of crucial importance in the management of ER+ breast cancer. Emerging evidence has revealed that the cell division regulator CDC20 exhibits an oncogenic function and plays important roles in tumourigenesis and progression of solid tumours. In this study, we investigated the prognostic and predictive role of CDC20 in early ER+ breast cancer patients.MethodsThe biological and clinical impact of CDC20 expression was assessed in large clinical annotated cohort of ER+ breast cancer with long-term follow-up at the mRNA level, using METABRIC and KM-Plotter datasets, and the protein level using immunohistochemistry on patients presenting at Nottingham. CDC20 expression was correlated with clinico-pathological parameters, molecular subtypes, clinical outcome and efficacy of endocrine therapy.ResultsHigh CDC20 mRNA expression was associated with poor clinico-pathological parameters including large tumour size and high tumour grade (P

SlideGraph+ : whole slide image level graphs to predict HER2 status in breast cancer

Human epidermal growth factor receptor 2 (HER2) is an important prognostic and predictive factor which is overexpressed in 15–20% of breast cancer (BCa). The determination of its status is a key clinical decision making step for selection of treatment regimen and prognostication. HER2 status is evaluated using transcriptomics or immunohistochemistry (IHC) through in-situ hybridisation (ISH) which incurs additional costs and tissue burden and is prone to analytical variabilities in terms of manual observational biases in scoring. In this study, we propose a novel graph neural network (GNN) based model (SlideGraph) to predict HER2 status directly from whole-slide images of routine Haematoxylin and Eosin (H&E) stained slides. The network was trained and tested on slides from The Cancer Genome Atlas (TCGA) in addition to two independent test datasets. We demonstrate that the proposed model outperforms the state-of-the-art methods with area under the ROC curve (AUC) values 0.75 on TCGA and 0.80 on independent test sets. Our experiments show that the proposed approach can be utilised for case triaging as well as pre-ordering diagnostic tests in a diagnostic setting. It can also be used for other weakly supervised prediction problems in computational pathology. The SlideGraph code repository is available at https://github.com/wenqi006/SlideGraph along with an IPython notebook showing an end-to-end use case at https://github.com/TissueImageAnalytics/tiatoolbox/blob/develop/examples/full-pipelines/slide-graph.ipynb

Ki67 assessment in invasive luminal breast cancer: A comparative study between different scoring methods

Background: Ki67 reflects the proliferation activity in breast cancer (BC). However, an optimal method for its assessment in clinical settings has yet to be robustly defined. In this study, we compared several methods to score Ki67 to identify a reliable and reproducible method for routine practice.Methods: Sections from luminal BC cohort (n=1662) were immunohistochemically stained with Ki67 and were assessed for the percentage, pattern, and intensity of expression. Ki67 positivity was evaluated using three methods: (i) quantification of Ki67 positive cells among 1000 invasive tumour cells within hotspot, (ii) average estimation of Ki67 within a defined hotspot, and (iii) average estimation of Ki67 positivity within the whole section. Time required for scoring, inter-observer agreement and association with outcome were determined.Results: The mean percentage of Ki67 expression per 1000 cells method was 16%, while the mean value of Ki67 scores using the average estimation within hotspot and whole slide were 14% and 12%, respectively. Quantification of Ki67 positive cells within 1000 cells had the highest degree of consistency between observers, and the highest hazard ratio predicting patient outcome when compared to using different common Ki67 cut-offs, which was independent on the other two methods. Granular pattern of Ki67 expression was associated with poorer outcome as compared to the other patterns.Conclusion: Assessment of Ki67 expression using quantification positive cells among 1000 tumour cells is an optimal method to achieve high reliability and reproducibility. Comment on the predominant Ki67 expression pattern would add prognostic and predictive value in luminal BC

Kinesin family member-18A (KIF18A) is a predictive biomarker of poor benefit from endocrine therapy in early ER+ breast cancer

PURPOSE: Identification of effective and reliable biomarkers that could be used to predict the efficacy of endocrine therapy is of crucial importance to the management of oestrogen receptor positive (ER+) breast cancer (BC). KIF18A, a key regulator of cell cycle, is overexpressed in many human cancers, including BC. In this study, we investigated the role of KIF18A as a biomarker to predict the benefit from endocrine treatment in early ER + BC patients.METHODS: KIF18A expression was assessed at the genomic level using the METABRIC dataset to explore its prognostic and predictive value in ER + BC patients (n = 1506). Predictive significance of KIF18A mRNA was validated using KM-Plot datasets (n = 2061). KIF18A protein expression was assessed using immunohistochemistry in a large annotated series of early-stage ER + BC (n = 1592) with long-term follow-up.RESULTS: High mRNA and protein expression of KIF18A were associated with short recurrence-free survival (RFS), distant-metastasis free survival (DMFS) and BC specific survival (all P  less than 0.05) in ER + BC in patients who received no adjuvant treatment or adjuvant endocrine therapy. In multivariate analysis, high KIF18A expression was an independent prognostic biomarker for poor RFS (P = 0.027) and DMFS (P = 0.028) in patients treated with adjuvant endocrine therapy.Conclusion: KIF18A appears to be a candidate biomarker of a subgroup of ER + BC characterised by poor clinical outcome. High KIF18A expression has prognostic significance to predict poor benefit from endocrine treatment for patients with ER + BC. Therefore, measurement of KIF18A on ER + BC patients prior to treatment could guide clinician decision on benefit from endocrine therapy