Molecular evolution of breast cancer

Heterogeneous Evolution of Breast Cancer Cells-An Endogenous Molecular-Cellular Network Study

Breast cancer heterogeneity presents a significant challenge in clinical therapy, such as over-treatment and drug resistance. These challenges are largely due to its obscure normal epithelial origins, evolutionary stability, and transitions on the cancer subtypes. This study aims to elucidate the cellular emergence and maintenance of heterogeneous breast cancer via quantitative bio-process modeling, with potential benefit to therapeutic strategies for the disease. An endogenous molecular-cellular hypothesis posits that both pathological and physiological states are phenotypes evolved from and shaped by interactions among a number of conserved modules and cellular factors within a biological network. We hereby developed a model of core endogenous network for breast cancer in accordance with the theory, quantifying its intrinsic dynamic properties with dynamic modeling. The model spontaneously generates cell states that align with molecular classifications at both the molecular and modular level, replicating four widely recognized molecular subtypes of the cancer and validating against data extracted from the TCGA database. Further analysis shows that topologically, a singular progression gateway from normal breast cells to cancerous states is identified as the Luminal A-type breast cancer. Activated positive feedback loops are found to stabilize cellular states, while negative feedback loops facilitate state transitions. Overall, more routes are revealed on the cellular transition between stable states, and a traceable count explains the origin of breast cancer heterogeneity. Ultimately, the research intended to strength the search for therapeutic targets.

Luminal breast epithelial cells from wildtype and BRCA mutation carriers harbor copy number alterations commonly associated with breast cancer

Cancer-associated mutations have been documented in normal tissues, but the prevalence and nature of somatic copy number alterations and their role in tumor initiation and evolution is not well understood. Here, using single cell DNA sequencing, we describe the landscape of CNAs in >42,000 breast epithelial cells from women with normal or high risk of developing breast cancer. Accumulation of individual cells with one or two of a specific subset of CNAs (e.g. 1q gain and 16q, 22q, 7q, and 10q loss) is detectable in almost all breast tissues and, in those from BRCA1 or BRCA2 mutations carriers, occurs prior to loss of heterozygosity (LOH) of the wildtype alleles. These CNAs, which are among the most common associated with ductal carcinoma in situ (DCIS) and malignant breast tumors, are enriched almost exclusively in luminal cells not basal myoepithelial cells. Allele-specific analysis of the enriched CNAs reveals that each allele was independently altered, demonstrating convergent evolution of these CNAs in an individual breast. Tissues from BRCA1 or BRCA2 mutation carriers contain a small percentage of cells with extreme aneuploidy, featuring loss of TP53 , LOH of BRCA1 or BRCA2 , and multiple breast cancer-associated CNAs in addition to one or more of the common CNAs in 1q, 10q or 16q. Notably, cells with intermediate levels of CNAs are not detected, arguing against a stepwise gradual accumulation of CNAs. Overall, our findings demonstrate that chromosomal alterations in normal breast epithelium partially mirror those of established cancer genomes and are chromosome- and cell lineage-specific.

Progression from ductal carcinoma in situ to invasive breast cancer: molecular features and clinical significance

Ductal carcinoma in situ (DCIS) represents pre-invasive breast carcinoma. In untreated cases, 25-60% DCIS progress to invasive ductal carcinoma (IDC). The challenge lies in distinguishing between non-progressive and progressive DCIS, often resulting in over- or under-treatment in many cases. With increasing screen-detected DCIS in these years, the nature of DCIS has aroused worldwide attention. A deeper understanding of the biological nature of DCIS and the molecular journey of the DCIS-IDC transition is crucial for more effective clinical management. Here, we reviewed the key signaling pathways in breast cancer that may contribute to DCIS initiation and progression. We also explored the molecular features of DCIS and IDC, shedding light on the progression of DCIS through both inherent changes within tumor cells and alterations in the tumor microenvironment. In addition, valuable research tools utilized in studying DCIS including preclinical models and newer advanced technologies such as single-cell sequencing, spatial transcriptomics and artificial intelligence, have been systematically summarized. Further, we thoroughly discussed the clinical advancements in DCIS and IDC, including prognostic biomarkers and clinical managements, with the aim of facilitating more personalized treatment strategies in the future. Research on DCIS has already yielded significant insights into breast carcinogenesis and will continue to pave the way for practical clinical applications.

Breast cancer screening in women taking hormone replacement therapy needs updating

Breast cancer screening by mammography is widely used. The diagnostic accuracy is limited, with a positive predictive value of 16%. Therefore, a stepwise investigation, with repeat mammography and confirmation by pathology, is usually proposed. Although this stepwise investigation intends to avoid overtreatment, the many false positives result in unnecessary fear and diagnostic surgery in many women. The false negatives are not known since these women have not been investigated. Given the estimated low risk of missing breast cancer and the slow growth, repeating a screening mammography every two years is sufficient. The false positive screening results, increase with breast density, and breast density increases when hormone replacement therapy (HRT) is given. It, therefore, is suggested to use clinical judgment and stop HRT for 3 to 6 months before repeating the mammography instead of starting immediately a stepwise investigation in all women.

Immune infiltration, aggressive pathology, and poor survival outcomes in RECQL helicase deficient breast cancers

RECQL is essential for genomic stability. Here, we evaluated RECQL in 449 pure ductal carcinomas in situ (DCIS), 152 DCIS components of mixed DCIS/invasive breast cancer (IBC) tumors, 157 IBC components of mixed DCIS/IBC and 50 normal epithelial terminal ductal lobular units (TDLUs). In 726 IBCs, CD8+, FOXP3+, IL17+, PDL1+, PD1+ T-cell infiltration (TILs) were investigated in RECQL deficient and proficient cancers. Tumor mutation burden (TMB) was evaluated in five RECQL germ-line mutation carriers with IBC by genome sequencing. Compared with normal epithelial cells, a striking reduction in nuclear RECQL in DCIS was evident with aggressive pathology and poor survival. In RECQL deficient IBCs, CD8+, FOXP3+, IL17+ or PDL1+ TILs were linked with aggressive pathology and shorter survival. In germline RECQL mutation carriers, increased TMB was observed in 4/5 tumors. We conclude that RECQL loss is an early event in breast cancer and promote immune cell infiltration.

Invasive Breast Cancer: miR-24-2 Targets Genes Associated with Survival and Sensitizes MDA-MB-231 Cells to Berberine

MicroRNA aberrations including that of miR-24-2 have been reported in various cancers. However, the target genes for miR-24-2 are yet to be identified and validated in invasive breast cancer and the triple-negative breast cancer (TNBC). Using in silico approaches and gene expression analyses, we identified and validated the target genes of miR-24-2 in invasive breast cancer, majority of which were TNBC. We studied the translational potential of these target genes using berberine in a TNBC cell line. Differentially expressed genes targeted by miR-24-2 were identified and analyzed for their survival effects using the The Cancer Genome Atlas-Breast Invasive Carcinoma (-BRCA) samples. Furthermore, we carried out protein-protein interaction, Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, gene expression, and Kaplan-Meier survival analyses using common targets of miR-24-2 in invasive breast cancer/TNBC. We identified 11 biomarker candidate genes as crucial targets of miR-24-2. The survival of breast cancer patients was significantly associated with the low expressions of nine genes, including RACGAP1, KIAA1199, TIMM17A, LYRM7, IL1R1, SLC1A3, DTX4, L1CAM, and SAP30-like (SAP30L), and high expressions of two genes, SOD2 and HLA-DQB2. These in silico findings were validated by overexpressing miR-24-2 and assessing the expression pattern of these target genes in the TNBC MDA-MB-231 cells. miR-24-2 overexpression inhibited (by 20%; p < 0.001) cell proliferation and sensitized the anticancer effect of berberine. In all, this study reports on the novel target genes of miR-24-2 in invasive breast cancer/TNBC, and that miR-24-2 sensitizes MDA-MB-231 cells to berberine. These data lend evidence for the translational potentials of miR-24-2 for invasive breast cancer diagnostic and therapeutic innovation.

Clinicopathologic and genomic features of lobular like invasive mammary carcinoma: is it a distinct entity?

This study describes "lobular-like invasive mammary carcinomas" (LLIMCas), a group of low- to intermediate-grade invasive mammary carcinomas with discohesive, diffusely infiltrative cells showing retained circumferential membranous immunoreactivity for both E-cadherin and p120. We analyzed the clinical-pathologic features of 166 LLIMCas compared to 104 classical invasive lobular carcinomas (ILCs) and 100 grade 1 and 2 invasive ductal carcinomas (IDCs). Tumor size and pT stage of LLIMCas were intermediate between IDCs and ILCs, and yet often underestimated on imaging and showed frequent positive margins on the first resection. Despite histomorphologic similarities to classical ILC, the discohesion in LLIMCa was independent of E-cadherin/p120 immunophenotypic alteration. An exploratory, hypothesis-generating analysis of the genomic features of 14 randomly selected LLIMCas and classical ILCs (7 from each category) was performed utilizing an FDA-authorized targeted capture sequencing assay (MSK-IMPACT). None of the seven LLIMCas harbored CDH1 loss-of-function mutations, and none of the CDH1 alterations detected in two of the LLIMCas was pathogenic. In contrast, all seven ILCs harbored CDH1 loss-of-function mutations coupled with the loss of heterozygosity of the CDH1 wild-type allele. Four of the six evaluable LLIMCas were positive for CDH1 promoter methylation, which may partially explain the single-cell infiltrative morphology seen in LLIMCa. Further studies are warranted to better define the molecular basis of the discohesive cellular morphology in LLIMCa. Until more data becomes available, identifying LLIMCas and distinguishing them from typical IDCs and ILCs would be justified. In patients with LLIMCas, preoperative MRI should be entertained to guide surgical management.

Glycosylation in breast cancer progression and mammary development: Molecular connections and malignant transformations

INTRODUCTION

The cellular behavior in normal mammary gland development and the progression of breast cancer is like the relationship between an object and its mirror image: they may appear similar, but their essence is completely different. Breast cancer can be considered as temporal and spatial aberrations of normal development in mammary gland. Glycans have been shown to regulate key pathophysiological steps during mammary development and breast cancer progression, and the glycoproteins that play a key role in both processes can affect the normal differentiation and development of mammary cells, and even cause malignant transformation or accelerate tumorigenesis due to differences in their type and level of glycosylation.

KEY FINDINGS

In this review, we summarize the roles of glycan alterations in essential cellular behaviors during breast cancer progression and mammary development, and also highlight the importance of key glycan-binding proteins such as epidermal growth factor receptor, transforming growth factor β receptors and other proteins, which are pivotal in the modulation of cellular signaling in mammary gland. Our review takes an overall view of the molecular interplay, signal transduction and cellular behaviors in mammary gland development and breast cancer progression from a glycobiological perspective.

SIGNIFICANCE

This review will give a better understanding of the similarities and differences in glycosylation between mammary gland development and breast cancer progression, laying the foundation for elucidating the key molecular mechanisms of glycobiology underlying the malignant transformation of mammary cells.

Ductal Carcinoma in Situ: A Detailed Review of Current Practices

Ductal carcinoma in situ is a challenge for breast surgeons, beginning with its difficult radiological detection and continuing with its contentious multimodal treatment and management. It is becoming more common as a result of widespread screening mammography and usually manifests as a cluster of calcifications. Patients are usually asymptomatic or present with a small, palpable lump. It is, however, a premalignant lesion that has the potential to progress to invasive carcinoma and is treated similarly with multimodal therapy. Treatment options currently include total or simple mastectomy with sentinel lymph node biopsy or lumpectomy with radiation. Tamoxifen and human epidermal growth factor receptor two suppression therapy are examples of adjuvant therapy. A review of consensus guidelines and literature was performed, in which we included the available online literature on the concerned topic from 2000-2022. This article is not a complete review of all the available literature; rather, it is a comprehensive review of the topic and its current management guidelines.

T-type Ca2+ channels and their relationship with pre-neoplastic and neoplastic lesions in the human breast

The expression of T-type voltage-dependent Ca2+ channels (Cav3) has been previously observed in breast cancer, but their expression and subcellular localization were not evaluated in pre-neoplastic lesions. Therefore, this work aimed to evaluate protein expression and subcellular localization of T-type channel isoforms in human breast tissue samples. Protein expressions of CaV3.1, CaV3.2, and CaV3.3 were evaluated by immunohistochemistry in breast without alteration, in proliferative non-neoplastic lesions, and in neoplastic ductal epithelial lesions of the human breast. CaV3.1, CaV3.2, and CaV3.3 nuclear expressions were decreased in advanced stages of neoplastic transformation, whereas CaV3.1 and CaV3.2 cytoplasmic expression increased. Also, the decrease in nuclear expression was correlated with an increase in cytoplasmic expression for CaV3.1 isoform. The change in CaV3 protein expression and subcellular localization are consistent with the neoplastic transformation stages of mammary epithelial cells, evident in early neoplastic lesions, such as ductal carcinomas in situ. These results suggest a possible involvement of CaV3 in the carcinogenic processes and could be considered as a potential pharmacological target in new therapies for breast cancer treatment.

Invasive lobular carcinoma with extracellular mucin (ILCEM): clinicopathologic and molecular characterization of a rare entity

Invasive lobular carcinoma with extracellular mucin (ILCEM) is a rare histologic subtype of breast cancer. Little is known about the pathologic or genomic signatures that distinguish ILCEM from classic invasive lobular carcinoma (ILC) or mucinous carcinoma. We studied 17 breast cancers with lobular morphology and extracellular mucin. Thirteen tumors with sufficient tissue for DNA extraction were analyzed by a next generation sequencing (NGS) assay that interrogates 447 genes for mutations and copy number variations (CNVs). Median patient age was 66 yrs (range: 31-77 yrs). Sixteen patients presented with masses, 7 of which were >2 cm. Seven patients had lymph node metastases. The cases of ILCEM were moderately (n = 13) or poorly differentiated (n = 4), frequently exhibiting variant morphology that has not been previously described or emphasized, including grade 3 nuclei (n = 11), diffuse signet ring cells (n = 10), solid growth (n = 4), tumor necrosis (n = 3) or apocrine features (n = 2). All tumors showed absent or reduced membranous E-cadherin expression. Concurrent lobular carcinoma in situ (LCIS) was seen in 11/17 cases, 1 of which was a striking example of signet ring cell LCIS with extracellular mucin. Receptor profiles were ER+/HER2- (n = 15) and ER+/HER2+ (n = 2). With a median follow-up of 83.5 months (range: 3-171 months) in 12 patients with available information, 8 patients had recurrences resulting in 4 cancer-related deaths. The most common CNVs were 16q loss (n = 11) and 1q gain (n = 9). CDH1 gene-level alterations were detected in all but one case, including frameshift (n = 7), nonsense (n = 2), and donor splice site (n = 1) mutations and indels (n = 2). Recurrent mutations were also seen in PIK3CA (n = 3), POLQ (n = 3), TP53 (n = 3), ERBB3 (n = 3), ERBB2 (n = 2), and RUNX1 (n = 2). Genes with recurrent amplifications included GATA3 (n = 4), FOXA1 (n = 3), CCND1 (n = 2). Our data highlights ILCEM as a distinct variant of ILC that often presents with higher-grade and variant morphologic features and is associated with an aggressive clinical course. NGS data support an overall lobular-type molecular profile and reveal potentially targetable alterations in a subset of cases with recurrence.

Genetic instability-related lncRNAs predict prognosis and influence the immune microenvironment in breast cancer

Genome instability is a hallmark of cancer, and the function of lncRNAs in regulating genomic stability has been gradually characterized. However, the prognostic value of lncRNAs related to genetic instability has not been found in breast cancer. Here we constructed a genetic instability-related lncRNA model including U62317.4, SEMA3B-AS1, MAPT-AS1, AC115837.2, LINC01269, AL645608.7, and GACAT2. This model can evaluate the risk and predict the survival outcomes of patients. Further analysis showed that the differentially expressed genes between the high- and low-risk groups were enriched in immunity and cornified envelope formation pathways. In addition, M2 macrophages infiltrated more obviously in the high-risk group. In summary, lncRNAs related to genetic instability may influence the development of breast cancer through immune infiltration and keratinization. This study provides a wider insight into breast cancer development and treatment.

L-type voltage-dependent Ca2+ channels expression involved in pre-neoplastic transformation of breast cancer

Background

Intracellular Ca2+ levels can modulate several cellular functions, including proliferation and other processes found altered in neoplastic cells. Helping to maintain Ca2+ homeostasis, L-type voltage-dependent Ca2+ channels had its expression identified in neoplasias, including breast cancer. Invasive breast carcinoma of no special type, the most common classification of breast cancer, has ductal hyperplasia and ductal carcinoma in situ as its possible non-obligate precursors. This channel’s role in breast cancer development from these precursors has not been investigated. Evaluate protein expression and subcellular localization of CaV1.1, CaV1.2, and CaV1.3 in mammary epithelium without alteration and neoplastic and non-neoplastic ductal proliferative lesions through immunohistochemistry was the aim of this investigation.

Methods

In the present study, CaV1.1, CaV1.2, and CaV1.3 protein expression was evaluated by immunohistochemistry in breast without alteration and in proliferative non-neoplastic and neoplastic ductal epithelial lesions of the human breast.

Results

It was observed that CaV1.3 presented a reduction in nuclear expression at neoplastic lesions, in addition to an increase in cytoplasmic CaV1.1 expression. The analyses of membrane immunostaining showed that CaV1.2 and CaV1.3 had an increase of expression as the lesions progressed in the stages leading to invasive carcinomas.

Conclusions

Changes in protein expression and subcellular localization of these channels during the progression stages indicate that they may be involved in neoplastic transformation.

Changes in the Serum Concentrations of Essential Trace Metals in Patients with Benign and Malignant Breast Cancers

Essential trace metals (ETMs) may play important roles in the pathophysiology of benign and malignant breast cancers. Our study aimed to find associations between ETMs and benign and malignant breast cancers. We recruited 146 patients with benign (n = 73) and malignant (n = 73) breast tumors and 95 healthy controls (HCs) from Peking University Third Hospital, Beijing, China. The serum concentrations of seven ETMs (Zn, Mn, Cu, Fe, Co, Ni, and Mo) were evaluated using inductively coupled plasma mass spectrometry (ICP-MS). The serum concentrations of Zn were significantly lower in the malignant group than in the HC group, whereas the concentrations of Cu (p < 0.001) were significantly higher in the malignant group. The concentrations of Fe were significantly lower in both malignant and benign groups than in the HC group (p < 0.05). We observed that the Fe/Cu ratio was lower and the Cu/Ni ratio was higher in the malignant group than in the HCs, as well as in the benign group than in the HCs. The serum concentration of Fe (OR = 0.454; 95% CI, 0.263, 0.784; p = 0.005) was negatively associated with breast tumors after adjusting for potential confounders, including age, BMI, and smoking, drinking and menopause statuses; that of Cu (OR = 2.274; 95% CI, 1.282, 4.031; p = 0.005) was positively associated. Changes in the concentrations of ETMs (Zn, Cu, Fe, and Ni) may be involved in the development of malignant breast cancer. The findings provide foundations for further exploration of ETMs in the prevention and treatment of breast tumors.

Molecular signatures of in situ to invasive progression for basal-like breast cancers: An integrated mouse model and human DCIS study

Ductal carcinoma in situ (DCIS) of the breast is a non-obligate precursor of Invasive Ductal Carcinoma (IDC) and thus the identification of features that may predict DCIS progression would be of potential clinical value. Experimental mouse models can be used to address this challenge by studying DCIS-to-IDC biology. Here we utilize single cell RNA sequencing (scRNAseq) on the C3Tag genetically engineered mouse model that forms DCIS-like precursor lesions and for which many lesions progress into end-stage basal-like molecular subtype IDC. We also perform bulk RNAseq analysis on 10 human synchronous DCIS-IDC pairs comprised of estrogen receptor (ER) positive and ER-negative subsets and utilize 2 additional public human DCIS data sets for comparison to our mouse model. By identifying malignant cells using inferred DNA copy number changes from the murine C3Tag scRNAseq data, we show the existence of cancer cells within the C3Tag pre-DCIS, DCIS, and IDC-like tumor specimens. These cancer cells were further classified into proliferative, hypoxic, and inflammatory subpopulations, which change in frequency in DCIS versus IDC. The C3Tag tumor progression model was also associated with increase in Cancer-Associated Fibroblasts and decrease in activated T cells in IDC. Importantly, we translate the C3Tag murine genomic findings into human DCIS where we find common features only with human basal-like DCIS, suggesting there are intrinsic subtype unique DCIS features. This study identifies several tumor and microenvironmental features associated with DCIS progression and may also provide genomic signatures that can identify progression-prone DCIS within the context of human basal-like breast cancers.

Subtype-Specific Tumour Immune Microenvironment in Risk of Recurrence of Ductal Carcinoma In Situ: Prognostic Value of HER2

Increasing evidence suggests that the significance of the tumour immune microenvironment (TIME) for disease prognostication in invasive breast carcinoma is subtype-specific but equivalent studies in ductal carcinoma in situ (DCIS) are limited. The purpose of this paper is to review the existing data on immune cell composition in DCIS in relation to the clinicopathological features and molecular subtype of the lesion. We discuss the value of infiltration by various types of immune cells and the PD-1/PD-L1 axis as potential markers of the risk of recurrence. Analysis of the literature available in PubMed and Medline databases overwhelmingly supports an association between densities of infiltrating immune cells, traits of immune exhaustion, the foci of microinvasion, and overexpression of HER2. Moreover, in several studies, the density of immune infiltration was found to be predictive of local recurrence as either in situ or invasive cancer in HER2-positive or ER-negative DCIS. In light of the recently reported first randomized DCIS trial, relating recurrence risk with overexpression of HER2, we also include a closing paragraph compiling the latest mechanistic data on a functional link between HER2 and the density/composition of TIME in relation to its potential value in the prognostication of the risk of recurrence.

Factors Indicating Surgical Excision in Classical Type of Lobular Neoplasia of the Breast

PURPOSE

Classical type of lobular neoplasia (LN) encompassing both atypical lobular hyperplasia and classical lobular carcinoma in situ of the breast is a lesion with uncertain malignant potential and has been the topic of several studies with conflicting outcome results. The aim of our study was to clarify outcome-relevant factors and treatment options of classical LN.

METHODS

We performed a pathological re-evaluation of the preoperative biopsy specimens and a retrospective clinical and radiological data analysis of 160 patients with LN from the Breast Center Zurich. Open surgery was performed in 65 patients, vacuum-assisted biopsy (VAB) in 79 patients, and surveillance after breast core needle biopsy (CNB) in 16 patients.

RESULTS

The upgrade rate into ductal carcinoma in situ/invasive cancer was the highest in case of imaging/histology discordance (40%). If the number of foci in the biopsy specimen was ≥3, the upgrade rate in the consecutive surgical specimens was increased (p = 0.01). The association of classical LN with histological microcalcification correlated with shortened disease-free survival (p < 0.01), whereas other factors showed no impact on follow-up.

CONCLUSIONS

Surveillance or subsequent VAB after CNB of LN is sufficient in most cases. Careful consideration of individual radiological and histological factors is required to identify patients with a high risk of upgrade into malignancy. In those cases, surgical excision is indicated.

CIP2A as a Key Regulator for AKT Phosphorylation Has Partial Impact Determining Clinical Outcome in Breast Cancer

Together with its reported ability to modulate AKT phosphorylation (p-AKT) status in several tumor types, the oncoprotein CIP2A has been described to induce breast cancer progression and drug resistance. However, the clinical and therapeutic relevance of the CIP2A/AKT interplay in breast cancer remains to be fully clarified. Here, we found high p-AKT levels in 80 out of 220 cases (36.4%), which were associated with negative estrogen receptor expression (p = 0.049) and CIP2A overexpression (p < 0.001). Interestingly, p-AKT determined substantially shorter overall (p = 0.002) and progression-free survival (p = 0.003), and multivariate analyses showed its CIP2A-independent prognostic value. Moreover, its clinical relevance was further confirmed in the triple negative and HER2-positive subgroups after stratifying our series by molecular subtype. Functionally, we confirmed in vitro the role of CIP2A as a regulator of p-AKT levels in breast cancer cell lines, and the importance of the CIP2A/AKT axis was also validated in vivo. Finally, p-AKT also showed a higher predictive value of response to doxorubicin than CIP2A in ex vivo analyses. In conclusion, our findings suggest that CIP2A overexpression is a key contributing event to AKT phosphorylation and highlights the CIP2A/AKT axis as a promising therapeutic target in breast cancer. However, our observations highlight the existence of alternative mechanisms that regulate AKT signaling in a subgroup of breast tumors without altered CIP2A expression that determines its independent value as a marker of poor outcome in this disease.

Chemokines in Triple-Negative Breast Cancer Heterogeneity: New Challenges for Clinical Implications

Tumor heterogeneity is a hallmark of cancer and one of the primary causes of resistance to therapies. Triple-negative breast cancer (TNBC), which accounts for 15% to 20% of all breast cancers and is the most aggressive subtype, is very diverse, connected to metastatic potential and response to therapy. It is a very diverse disease at the molecular, pathologic, and clinical levels. TNBC is substantially more likely to recur and has a worse overall survival rate following diagnosis than other breast cancer subtypes. Chemokines, low molecular weight proteins that stimulate chemotaxis, have been shown to control the cues responsible for TNBC heterogeneity. In this review, we have focused on tumor heterogeneity and the role of chemokines in modulating tumor heterogeneity, since this is the most critical issue in treating TNBC. Additionally, we examined numerous cues mediated by chemokine networks that contribute to the heterogeneity of TNBC. Recent developments in our knowledge of the chemokine networks that regulate TNBC heterogeneity may pave the door for developing difficult-to-treat TNBC treatment options.

Quantification of long-term doxorubicin response dynamics in breast cancer cell lines to direct treatment schedules

While acquired chemoresistance is recognized as a key challenge to treating many types of cancer, the dynamics with which drug sensitivity changes after exposure are poorly characterized. Most chemotherapeutic regimens call for repeated dosing at regular intervals, and if drug sensitivity changes on a similar time scale then the treatment interval could be optimized to improve treatment performance. Theoretical work suggests that such optimal schedules exist, but experimental confirmation has been obstructed by the difficulty of deconvolving the simultaneous processes of death, adaptation, and regrowth taking place in cancer cell populations. Here we present a method of optimizing drug schedules in vitro through iterative application of experimentally calibrated models, and demonstrate its ability to characterize dynamic changes in sensitivity to the chemotherapeutic doxorubicin in three breast cancer cell lines subjected to treatment schedules varying in concentration, interval between pulse treatments, and number of sequential pulse treatments. Cell populations are monitored longitudinally through automated imaging for 600–800 hours, and this data is used to calibrate a family of cancer growth models, each consisting of a system of ordinary differential equations, derived from the bi-exponential model which characterizes resistant and sensitive subpopulations. We identify a model incorporating both a period of growth arrest in surviving cells and a delay in the death of chemosensitive cells which outperforms the original bi-exponential growth model in Akaike Information Criterion based model selection, and use the calibrated model to quantify the performance of each drug schedule. We find that the inter-treatment interval is a key variable in determining the performance of sequential dosing schedules and identify an optimal retreatment time for each cell line which extends regrowth time by 40%-239%, demonstrating that the time scale of changes in chemosensitivity following doxorubicin exposure allows optimization of drug scheduling by varying this inter-treatment interval.

Acquired chemoresistance is a common cause of treatment failure in cancer. The scheduling of a multi-dose course of chemotherapeutic treatment may influence the dynamics of acquired chemoresistance, and drug schedule optimization may increase the duration of effectiveness of a particular chemotherapeutic agent for a particular patient. Here we present a method for experimentally optimizing an in vitro drug schedule through iterative rounds of experimentation and computational analysis, and demonstrate the method’s ability to improve the performance of doxorubicin treatment in three breast carcinoma cell lines. Specifically, we find that the interval between drug exposures can be optimized while holding drug concentration and number of treatments constant, suggesting that this may be a key variable to explore in future drug schedule optimization efforts. We further use this method’s model calibration and selection process to extract information about the underlying biology of the doxorubicin response, and find that the incorporation of delays on both cell death and regrowth are necessary for accurate parameterization of cell growth data.

Viscoelasticity, Like Forces, Plays a Role in Mechanotransduction

Viscoelasticity and its alteration in time and space has turned out to act as a key element in fundamental biological processes in living systems, such as morphogenesis and motility. Based on experimental and theoretical findings it can be proposed that viscoelasticity of cells, spheroids and tissues seems to be a collective characteristic that demands macromolecular, intracellular component and intercellular interactions. A major challenge is to couple the alterations in the macroscopic structural or material characteristics of cells, spheroids and tissues, such as cell and tissue phase transitions, to the microscopic interferences of their elements. Therefore, the biophysical technologies need to be improved, advanced and connected to classical biological assays. In this review, the viscoelastic nature of cytoskeletal, extracellular and cellular networks is presented and discussed. Viscoelasticity is conceptualized as a major contributor to cell migration and invasion and it is discussed whether it can serve as a biomarker for the cells' migratory capacity in several biological contexts. It can be hypothesized that the statistical mechanics of intra- and extracellular networks may be applied in the future as a powerful tool to explore quantitatively the biomechanical foundation of viscoelasticity over a broad range of time and length scales. Finally, the importance of the cellular viscoelasticity is illustrated in identifying and characterizing multiple disorders, such as cancer, tissue injuries, acute or chronic inflammations or fibrotic diseases.

Automatic breast carcinoma detection in histopathological micrographs based on Single Shot Multibox Detector

Background

A diagnosis with histological classification by pathologists is very important for appropriate treatments to improve the prognosis of patients with breast cancer. However, the number of pathologists is limited, and assisting the pathological diagnosis by artificial intelligence becomes very important. Here, we presented an automatic breast lesions detection model using microscopic histopathological images based on a Single Shot Multibox Detector (SSD) for the first time and evaluated its significance in assisting the diagnosis.

Methods

We built the data set and trained the SSD model with 1361 microscopic images and evaluated using 315 images. Pathologists and medical students diagnosed the images with or without the assistance of the model to investigate the significance of our model in assisting the diagnosis.

Results

The model achieved 88.3% and 90.5% diagnostic accuracies in 3-class (benign, non-invasive carcinoma, or invasive carcinoma) or 2-class (benign or malignant) classification tasks, respectively, and the mean intersection over union was 0.59. Medical students achieved a remarkably higher diagnostic accuracy score (average 84.7%) with the assistance of the model compared to those without assistance (average 67.4%). Some people diagnosed images in a short time using the assistance of the model (shorten by average 6.4 min) while others required a longer time (extended by 7.2 min).

Conclusion

We presented the automatic breast lesions detection method at high speed using histopathological micrographs. The present system may conveniently support the histological diagnosis by pathologists in laboratories.

Intraductal Injections into the Mouse Mammary Gland

The mammary intraductal xenografting technique has been established to inject cells or other substances directly into the mammary ducts of female mice. Using this refined xenografting method provides the possibility of mimicking the normal microenvironment of preinvasive breast lesions including, ductal carcinoma in situ (DCIS), to study of the progression of DCIS to invasive breast cancer in a more relevant manner than with other mammary xenografting methods. Xenografting into the mammary fat pad delivers cells directly into the stroma and bypasses the occurrence of invasive transition, during which cells invade through the basement membrane. Either breast cancer cell lines or patient-derived breast cancer cells can be injected into the mammary duct using this protocol to model breast cancer progression. This protocol will cover the procedures required to perform this technique.

The distribution of reproductive risk factors disclosed the heterogeneity of receptor-defined breast cancer subtypes among Tanzanian women

Background

Recent epidemiological studies suggest that reproductive factors are associated with breast cancer (BC) molecular subtypes. However, these associations have not been thoroughly studied in the African populations. The present study aimed to investigate the prevalence of BC molecular subtypes and assess their association with reproductive factors in Tanzanian BC patients.

Methods

This hospital-based case-only cross-sectional study consisted of 263 histologically confirmed BC patients in Tanzania. Clinico-pathological data, socio-demographic characteristics, anthropometric measurements, and reproductive risk factors were examined using the Chi-square test and one-way ANOVA. The association among reproductive factors and BC molecular subtypes was analyzed using multinomial logistic regression. The heterogeneity of the associations was assessed using the Wald test.

Results

We found evident subtype heterogeneity for reproductive factors. We observed that post-menopausal status was more prevalent in luminal-A subtype, while compared to luminal-A subtype, luminal-B and HER-2 enriched subtypes were less likely to be found in post-menopausal women (OR: 0.21, 95%CI 0.10–0.41, p = 0.001; OR: 0.39, 95%CI 0.17–0.89, p = 0.026, respectively). Also, the luminal-B subtype was more likely to be diagnosed in patients aged ≤ 40 years than the luminal-A subtype (OR: 2.80, 95%CI 1.46–5.32, p = 0.002). Women who had their first full-term pregnancy at < 30 years were more likely to be of luminal-B (OR: 2.71, 95%CI 1.18–4.17, p = 0.018), and triple-negative (OR: 2.28, 95%CI 1.02–4.07, p = 0.044) subtypes relative to luminal-A subtype. Furthermore, we observed that breastfeeding might have reduced odds of developing luminal-A, luminal-B and triple-negative subtypes. Women who never breastfed were more likely to be diagnosed with luminal-B and triple-negative subtypes when compared to luminal-A subtype (OR: 0.46, 95%CI 0.22–0.95, p = 0.035; OR: 0.41, 95%CI 0.20–0.85, p = 0.017, respectively).

.

Conclusion

Our results are the first data reporting reproductive factors heterogeneity among BC molecular subtypes in Tanzania. Our findings suggest that breast-feeding may reduce the likelihood of developing luminal-A, luminal-B, and triple-negative subtypes. Meanwhile, the first full-term pregnancy after 30 years of age could increase the chance of developing luminal-A subtype, a highly prevalent subtype in Tanzania. More interventions to promote modifiable risk factors across multiple levels may most successfully reduce BC incidence in Africa.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-021-01536-6.

Viscoelasticity Acts as a Marker for Tumor Extracellular Matrix Characteristics

Biological materials such as extracellular matrix scaffolds, cancer cells, and tissues are often assumed to respond elastically for simplicity; the viscoelastic response is quite commonly ignored. Extracellular matrix mechanics including the viscoelasticity has turned out to be a key feature of cellular behavior and the entire shape and function of healthy and diseased tissues, such as cancer. The interference of cells with their local microenvironment and the interaction among different cell types relies both on the mechanical phenotype of each involved element. However, there is still not yet clearly understood how viscoelasticity alters the functional phenotype of the tumor extracellular matrix environment. Especially the biophysical technologies are still under ongoing improvement and further development. In addition, the effect of matrix mechanics in the progression of cancer is the subject of discussion. Hence, the topic of this review is especially attractive to collect the existing endeavors to characterize the viscoelastic features of tumor extracellular matrices and to briefly highlight the present frontiers in cancer progression and escape of cancers from therapy. Finally, this review article illustrates the importance of the tumor extracellular matrix mechano-phenotype, including the phenomenon viscoelasticity in identifying, characterizing, and treating specific cancer types.

Inhibin β-A (INHBA) induces epithelial-mesenchymal transition and accelerates the motility of breast cancer cells by activating the TGF-β signaling pathway

Accumulating evidence indicates that INHBA (Inhibin β-A, a member of the TGF-β superfamily) functions as an oncogene in cancer progression. However, little is known as to how INHBA regulates the progression and aggressiveness of breast cancer (BC). This study explored the function and underlying mechanism of INHBA in epithelial-mesenchymal transition (EMT) of BC cells. INHBA expression in BC cell lines was measured using RT-qPCR and Western blot. The would-healing and transwell migration assays were used to investigate the effect of INHBA overexpression or silencing on BC cell motility. Moreover, the expression levels of EMT-related genes were quantified after overexpressing or silencing of INHBA. Based on published dataset, INHBA was significantly upregulated in BC tissues compared to the adjacent normal tissues. A higher level of INHBA expression was also correlated with a poor survival in BC patients. In addition, in vitro study showed that INHBA played an indispensable role in promoting BC cell proliferation and invasion. Mechanistically, INHBA induced epithelial-mesenchymal transition (EMT) and accelerated the motility of BC cells by activating TGF-β-regulated genes. In conclusion, INHBA plays a functional role in supporting EMT phenotype of BC cells, and it may serve as a diagnostic biomarker and a potential therapeutic target for BC treatment.

Colorimetric histology using plasmonically active microscope slides

The human eye can distinguish as many as 10,000 different colours but is far less sensitive to variations in intensity¹, meaning that colour is highly desirable when interpreting images. However, most biological samples are essentially transparent, and nearly invisible when viewed using a standard optical microscope². It is therefore highly desirable to be able to produce coloured images without needing to add any stains or dyes, which can alter the sample properties. Here we demonstrate that colorimetric histology images can be generated using full-sized plasmonically active microscope slides. These slides translate subtle changes in the dielectric constant into striking colour contrast when samples are placed upon them. We demonstrate the biomedical potential of this technique, which we term histoplasmonics, by distinguishing neoplastic cells from normal breast epithelium during the earliest stages of tumorigenesis in the mouse MMTV-PyMT mammary tumour model. We then apply this method to human diagnostic tissue and validate its utility in distinguishing normal epithelium, usual ductal hyperplasia, and early-stage breast cancer (ductal carcinoma in situ). The colorimetric output of the image pixels is compared to conventional histopathology. The results we report here support the hypothesis that histoplasmonics can be used as a novel alternative or adjunct to general staining. The widespread availability of this technique and its incorporation into standard laboratory workflows may prove transformative for applications extending well beyond tissue diagnostics. This work also highlights opportunities for improvements to digital pathology that have yet to be explored.

Differences in tumour heterogeneity based on dynamic contrast-enhanced MRI between tumour and peritumoural stroma for predicting Ki-67 status of invasive ductal carcinoma

AIM

To evaluate and compare the heterogeneity of intratumour and peritumour areas in the prediction of Ki-67 of invasive ductal carcinoma (IDC) and the predictive accuracy of different contrast frames based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

MATERIALS AND METHODS

This study included 88 patients with histologically confirmed IDC with 57 patients with high Ki-67 status and 31 patients with low Ki-67 status. All patients underwent DCE-MRI before surgery. A grey-level co-occurrence matrix (GLCM) was performed on slice-matched images from six frames by drawing the region of the interest (ROI) on the inner and outer regions of the tumours. The correlations between texture characteristics and Ki-67 status of lesions were analysed, using the Mann-Whitney test and receiver operating characteristic curve analysis.

RESULTS

In the high-Ki-67 group, the entropy was significantly higher than that of the low-Ki-67 group (p<0.001). The entropy obtained, based on the tumour boundary as a band-like area inside and outside at the first post-contrast series, revealed the highest receiver operating characteristic (AUC = 0.765). In the multivariate analysis, a higher entropy value (>4.305; p<0.001) remained independently associated with a high-Ki-67 status after adjustment for menopausal status, tumour size, histologic grade, oestrogen receptor (ER) status, and progesterone receptor (PR) status. The other parameters did not show significant differences between the high- and low-Ki-67 groups.

CONCLUSION

Heterogeneity analysis based on DCE-MRI could discriminate between high- and low-Ki-67 status. Texture characteristics from the band-like region inside and outside the tumour boundary could predict the Ki-67 status and showed higher accuracy.

Complete Removal of the Lesion as a Guidance in the Management of Patients with Breast Ductal Carcinoma In Situ

Simple Summary

A diagnosis of ductal carcinoma in situ, made on biopsy, is often followed by surgery or radiotherapy because of the risk of an upgrading disease upon subsequent surgical specimens, finding invasive carcinoma. In order to select which patients can be spared overtreatments and alternatively followed with active surveillance, we retrospectively reviewed 2173 vacuum assisted breast biopsies. Our goal was to demonstrate if complete removal of the lesion by biopsy, documented by mammograms, can be a valid criterion to select the patients that can be spared further treatments. The results of our study demonstrate a significant lower upgrading rate of disease when the lesion is completely removed. Thus, performing a mammogram to document the absence of residual lesion following vacuum-assisted breast biopsy (VABB) allows us to reduce overtreatments and to select which patients can be followed with an active surveillance, sparing unjustified public health costs.

Abstract

Background: Considering highly selected patients with ductal carcinoma in situ (DCIS), active surveillance is a valid alternative to surgery. Our study aimed to show the reliability of post-biopsy complete lesion removal, documented by mammogram, as additional criterion to select these patients. Methods: A total of 2173 vacuum-assisted breast biopsies (VABBs) documented as DCIS were reviewed. Surgery was performed in all cases. We retrospectively collected the reports of post-VABB complete lesion removal and the histological results of the biopsy and surgery. We calculated the rate of upgrade of DCIS identified on VABB upon excision for patients with post-biopsy complete lesion removal and for those showing residual lesion. Results: We observed 2173 cases of DCIS: 408 classified as low-grade, 1262 as intermediate-grade, and 503 as high-grade. The overall upgrading rate to invasive carcinoma was 15.2% (330/2173). The upgrade rate was 8.2% in patients showing mammographically documented complete removal of the lesion and 19% in patients without complete removal. Conclusion: The absence of mammographically documented residual lesion following VABB was found to be associated with a lower upgrading rate of DCIS to invasive carcinoma on surgical excision and should be considered when deciding the proper management DCIS diagnosis.

Concordance of the 21-gene assay between core needle biopsy and resection specimens in early breast cancer patients

BACKGROUND

Adjuvant therapy decisions may be partly based on the results of a multigene quantitative reverse transcription-polymerase chain reaction (RT-PCR)-based assay: the 21-gene recurrence score (RS) test of resection specimens. When necessary, core needle biopsy (CNB) may be considered as a surrogate. Here, we evaluated the concordance in gene expression according to results from RT-PCR-based RS testing between paired CNBs and resection specimens.

METHODS

CNBs and resection specimens from 50 breast cancer (BC) patients were tested to calculate RSs. First, we examined the concordance of the ER, PR and HER-2 status of tissue samples indicated by immunohistochemical (IHC) and RT-PCR analyses. Then, we compared the IHC findings of ER, PR, HER-2 and Ki-67 staining across paired samples. Ultimately, the RS and single-gene results for ER, PR, HER-2 and Ki-67 were explored between paired samples.

RESULTS

The concordance between IHC and RT-PCR was 100%, 80.0% and 100% for ER, PR and HER-2, respectively, in both resection specimens and CNBs. The concordance for IHC ER, PR, HER-2 and Ki-67 status was 100%, 94.0%, 52.0% and 82.0%, respectively, between paired samples. RS results from paired samples showed a strong correlation. The overall concordance in RS group classification between samples was 74%, 72% and 78% based on traditional cutoffs, TAILORx cutoffs and ASCO guidelines, respectively. ER, PR, HER-2 and Ki-67 were modestly- to- strongly correlated between paired samples according to the RT-PCR results.

CONCLUSION

A modest- to- strong correlation of ER, PR, HER-2 and Ki-67 gene expression and RS between CNBs and resection specimens was observed in the present study. The 21-gene RS test could be reliably performed on CNBs. ER, PR and HER-2 status showed remarkable concordance between the IHC and RT-PCR analyses. The concordance between paired samples was high for the IHC ER, PR and Ki-67 results and low for HER-2.

Invasive lobular carcinoma of the breast: the increasing importance of this special subtype

Invasive lobular carcinoma (ILC) is the most common of the breast cancer special types, accounting for up to 15% of all breast cancer cases. ILCs are noted for their lack of E-cadherin function, which underpins their characteristic discohesive growth pattern, with cells arranged in single file and dispersed throughout the stroma. Typically, tumours are luminal in molecular subtype, being oestrogen and progesterone receptor positive, and HER2 negative. Since last reviewing the lobular literature (McCart Reed et al., Breast Cancer Res 17:12, 2015), there has been a considerable increase in research output focused on this tumour type, including studies into the pathology and management of disease, a high-resolution definition of the genomic landscape of tumours as well as the evolution of several potential therapeutic avenues. There abounds a huge amount of new data, which we will review herein.

Derivation of a nuclear heterogeneity image index to grade DCIS

Abnormalities in cell nuclear morphology are a hallmark of cancer. Histological assessment of cell nuclear morphology is frequently used by pathologists to grade ductal carcinoma in situ (DCIS). Objective methods that allow standardization and reproducibility of cell nuclear morphology assessment have potential to improve the criteria needed to predict DCIS progression and recurrence. Aggressive cancers are highly heterogeneous. We asked whether cell nuclear morphology heterogeneity could be incorporated into a metric to classify DCIS. We developed a nuclear heterogeneity image index to objectively, and quantitatively grade DCIS. A whole-tissue cell nuclear morphological analysis, that classified tumors by the worst ten percent in a duct-by-duct manner, identified nuclear size ranges associated with each DCIS grade. Digital image analysis further revealed increasing heterogeneity within ducts or between ducts in tissues of worsening DCIS grade. The findings illustrate how digital image analysis comprises a supplemental tool for pathologists to objectively classify DCIS and in the future, may provide a method to predict patient outcome through analysis of nuclear heterogeneity.

The comparison of miRNAs that respond to anti-breast cancer drugs and usnic acid for the treatment of breast cancer

This study was designed to compare usnic acid with anti-breast cancer drug molecules (A-BCDM) routinely used in the treatment of breast cancer. The miRNA information of 17 anti-breast cancer drug used in breast cancer treatment was obtained from the Small Molecule-miRNA Network-Based Inferance (SMIR-NBI) tool. We had been determined common and different expressed miRNAs between 17 A-BCDM & usnic acid and were classified according to the common miRNAs to reveal molecular similarity. As a result of the bioinformatic analyzes, 20 common miRNAs were determined between 17 A-BCDM and usnic acid. The common miRNAs were analyzed with bioinformatic tolls for determining pathways and targets. The most common miRNAs for 6 of 17 A-BCDM and usnic acid were determined as miR-374a-5p and miR-26a-5p. We compared the anti-proliferative effect of usnic acid and one of the 17 A-BCDM that tamoxifen on MDA-MB-231 triple negative breast cancer cell with real-time cell analysis system. The real time PCR assay was carried out with miR-26a-5p for evaluate to expression level of MDA-MB-231 breast cancer cell and MCF-12A non-cancerous epithelial breast cell. As a result of study, usnic acid as novel candidate drug molecule showed high similarity ratio with 5-Fluorouracil, Sulindac Sulfide, Curcumin and Cisplatin A-BCDM used in treatment of breast cancer. miR-26a-5p as common response miRNA of usnic acid and tamoxifen was showed a decreased level of expression by validated qRT-PCR assay. The obtained from study, in addition to 17 A-BCDM, usnic acid has also the potential to be used as a candidate molecule in the treatment of breast cancer. Moreover, miR-26a-5p might be used as a biomarker in the treatment of breast cancer but further analysis is required.

Ubiquitin-specific protease 7 downregulation suppresses breast cancer in vitro

Because breast cancer is complicated at the pathological, histological, clinical, and molecular levels, identification of new genetic targets against carcinogenic pathways is required to generate clinically relevant treatment options. In the current study, ubiquitin-specific protease 7 (USP7), which regulates various cellular pathways including Mdm2, p53, and NF–κB, was selected as a potential gene editing strategy for breast cancer in vitro. Anticancer activity of USP7 gene suppression has been evaluated through cell proliferation, gene expression, cell cycle, sphere dissemination, and cell migration analysis. Here, siRNA and shRNA strategies and an allosteric small-molecule inhibitor of USP7 were used to define potential anticancer activity against MCF7 and T47D human breast cancer cell lines. Both blockage of deubiquitination by p5091 and knockdown of USP7 reduced cell proliferation, cell migration, colony formation, and sphere dissemination for both MCF7 and T47D breast cancer cell lines. Restriction of USP7 activity strongly enhanced apoptotic gene expression and reduced metastatic ability of breast cancer cell lines. This study describes one potential molecular target for the suppression of breast cancer proliferation and metastasis. Identification of USP7 as a promising gene editing candidate might open up the possibility of new molecular drug research in targeting the ubiquitination pathway in cancer.

Tumor size estimation of the breast cancer molecular subtypes using imaging techniques

Background and aim

In medical practice the classification of breast cancer is most commonly based on the molecular subtypes, in order to predict the disease prognosis, avoid over-treatment, and provide individualized cancer management. Tumor size is a major determiner of treatment planning, acting on the decision-making process, whether to perform breast surgery or administer neoadjuvant chemotherapy. Imaging methods play a key role in determining the tumor size in breast cancers at the time of the diagnosis.

We aimed to compare the radiologically determined tumor sizes with the corresponding pathologically determined tumor sizes of breast cancer at the time of the diagnosis, in correlation with the molecular subtypes.

Methods

Ninety-one patients with primary invasive breast cancer were evaluated. The main molecular subtypes were luminal A, luminal B, HER-2 positive, and triple-negative. The Bland-Altman plot was used for presenting the limits of agreement between the radiologically and the pathologically determined tumor sizes by the molecular subtypes.

Results

A significantly proportional underestimation was found for the luminal A subtype, especially for large tumors. The p-values for the magnetic resonance imaging, mammography, and ultrasonography were 0.020, 0.030, and <0.001, respectively. No statistically significant differences were observed among the radiologic modalities in determining the tumor size in the remaining molecular subtypes (p>0.05).

Conclusion

The radiologically determined tumor size was significantly smaller than the pathologically determined tumor size in the luminal A subtype of breast cancers when measured with all three imaging modalities. The differences were more prominent with ultrasonography and mammography. The underestimation rate increases as the tumor gets larger.

Potential of Using Cell-Free DNA and miRNA in Breast Milk to Screen Early Breast Cancer

Objective

An ideal sample source is critical for more reliable and sensitive early detection of nucleic acid changes associated with breast cancer. Breast milk (BM) is a good noninvasive origin for genetic testing of early breast cancer, but cells in BM are easily disintegrated. So we investigate here whether cell-free nucleic acid (cfNA) exists in BM in a more stable form and whether the quality of BM cfNA is good enough for genetic testing.

Methods

A self-designed qRT-PCR method was used to measure the existence and abundance of cfDNA. Quality of cfDNA and cfRNA were detected by capillary electrophoresis. Whole genome bisulfite sequencing and miRNA sequencing were used to explore the sources of cfDNA and cell-free miRNA in BM. The copy number analysis and z-test based on whole genome sequencing data were used to determine the integrity of genetic information in BM cfNA.

Results

We found that cell-free DNA and miRNA exist in the studied breast milk samples in a stable form that can tolerate incubation of BM at room temperature for at least 7 days. These cell-free nucleic acids come mainly from breast-derived cells and contain genetic information as good integrity as in BM cells. We further listed some candidate miRNAs as potential biomarkers for research of early breast cancer screening by analysis of previous reports and our data.

Conclusions

Our results suggest that cfDNA and cell-free miRNA in BM might be new noninvasive sample sources for finding early alterations of nucleic acid associated with the initiation and progression of breast cancer.

Genomic profiling of pleomorphic and florid lobular carcinoma in situ reveals highly recurrent ERBB2 and ERRB3 alterations

Pleomorphic LCIS (P-LCIS) and florid LCIS (F-LCIS) are morphologic variants distinguished from classic LCIS by marked nuclear pleomorphism and/or an expansile growth pattern with or without necrosis. Given the rarity of these LCIS variants, little data exist regarding their molecular pathogenesis, natural history, and optimal management. The purpose of this study was to genomically profile LCIS variants to gain further insight into their biology. Nineteen cases of pure LCIS variants (17 P-LCIS, 2 F-LCIS) diagnosed on core needle biopsy at our institution from 2006 to 2017 were included, five of which were upgraded to invasive cancer at excision. Macrodissected lesions were analyzed by a hybrid-capture next generation sequencing assay that surveyed exonic sequences of 447 genes for mutations and copy number variations (CNVs) and 191 regions across 60 genes for structural rearrangements. LCIS variants were all confirmed as E-cadherin negative by immunohistochemistry. Receptor profiles among the 17 P-LCIS cases included HR+/HER2- (nine cases), HR+/HER2+ (three cases), HR-/HER2+ (two cases), and HR-/HER2- (three cases). The two F-LCIS cases were HR+/HER2- and HR+/HER2+. All LCIS variants had genetic alterations consistent with a lobular phenotype including 1q gain (16 cases), 16q loss (18 cases), and CDH1 mutations (18 cases). Highly recurrent ERBB2 alterations were noted including mutations (13 cases) and amplifications (six cases). Other significant alterations included mutations in PIK3CA (six cases), RUNX1 (four cases), ERBB3 (four cases), and CBFB (three cases), as well as amplification of CCND1 (five cases). A TP53 mutation was identified in one case of HR-/HER2+ P-LCIS with signet ring cell features that lacked 1q gain and 16q loss. P-LCIS and F-LCIS contain genetic alterations characteristic of lobular neoplasia; however, these LCIS variants are distinguished from classical LCIS reported in the literature by their highly recurrent ERBB2 alterations.

Morphologic and Genomic Heterogeneity in the Evolution and Progression of Breast Cancer

: Breast cancer is a remarkably complex and diverse disease. Subtyping based on morphology, genomics, biomarkers and/or clinical parameters seeks to stratify optimal approaches for management, but it is clear that every breast cancer is fundamentally unique. Intra-tumour heterogeneity adds further complexity and impacts a patient's response to neoadjuvant or adjuvant therapy. Here, we review some established and more recent evidence related to the complex nature of breast cancer evolution. We describe morphologic and genomic diversity as it arises spontaneously during the early stages of tumour evolution, and also in the context of treatment where the changing subclonal architecture of a tumour is driven by the inherent adaptability of tumour cells to evolve and resist the selective pressures of therapy.

Sphingosine Kinase 1 in Breast Cancer-A New Molecular Marker and a Therapy Target

It is now well-established that sphingosine kinase 1 (SK1) plays a significant role in breast cancer development, progression, and spread, whereas SK1 knockdown can reverse these processes. In breast cancer cells and tumors, SK1 was shown to interact with various pathways involved in cell survival and chemoresistance, such as nuclear factor-kappa B (NFκB), Notch, Ras/MAPK, PKC, and PI3K. SK1 is upregulated by estrogen signaling, which, in turn, confers cancer cells with resistance to tamoxifen. Sphingosine-1-phosphate (S1P) produced by SK1 has been linked to tumor invasion and metastasis. Both SK1 and S1P are closely linked to inflammation and adipokine signaling in breast cancer. In human tumors, high SK1 expression has been linked with poorer survival and prognosis. SK1 is upregulated in triple negative tumors and basal-like subtypes. It is often associated with high phosphorylation levels of ERK1/2, SFK, LYN, AKT, and NFκB. Higher tumor SK1 mRNA levels were correlated with poor response to chemotherapy. This review summarizes the up-to-date evidence and discusses the therapeutic potential for the SK1 inhibition in breast cancer, with emphasis on the mechanisms of chemoresistance and combination with other therapies such as gefitinib or docetaxel. We have outlined four key areas for future development, including tumor microenvironment, combination therapies, and nanomedicine. We conclude that SK1 may have a potential as a target for precision medicine, its high expression being a negative prognostic marker in ER-negative breast cancer, as well as a target for chemosensitization therapy.

Pitfalls and controversies in pathology impacting breast cancer management

Introduction: Breast cancer is a heterogeneous disease, at morphological, molecular, and clinical levels and this has significant implications for the diagnosis and management of the disease. The introduction of breast screening, and the use of small tissue sampling for diagnosis, the recognition of new morphological and molecular subtypes, and the increasing use of neoadjuvant therapies have created challenges in pathological diagnosis and classification.Areas covered: Areas of potential difficulty include columnar cell lesions, particularly flat epithelial atypia, atypical ductal hyperplasia, lobular neoplasia and its variants, and a range of papillary lesions. Fibroepithelial, sclerosing, mucinous, and apocrine lesions are also considered. Established and newer prognostic and predictive markers, such as immune infiltrates, PD-1 and PD-L1 and gene expression assays are evaluated. The unique challenges of pathology assessment post-neoadjuvant systemic therapy are also explored.Expert opinion: Controversies in clinical management arise due to incomplete and sometimes conflicting data on clinicopathological associations, prognosis, and outcome. The review will address some of these challenges.

Know Thy Model: Charting Molecular Homology in Stromal Reprogramming Between Canine and Human Mammary Tumors

Spontaneous canine simple mammary tumors (CMTs) are often viewed as models of human breast cancer. Cancer-associated stroma (CAS) is central for initiation and progression of human cancer, and is likely to play a key role in canine tumors as well. Until recently, however, canine CAS in general, and in CMT in particular, lacked detailed characterization and it remained unclear how canine and human CAS compare. This void in knowledge regarding canine CAS and the resulting lack of unbiased cross-species analysis of molecular homologies and differences undermined the validity of the canine model for human disease. To assess stromal reprogramming in canine breast tumors, we have recently established a protocol to specifically isolate and analyze CAS and matched normal stroma from archival, formalin-fixed paraffin embedded (FFPE) clinical tumor samples using laser-capture microdissection followed by next-generation RNA-sequencing. Using this approach, we have analyzed stromal reprogramming in both malignant canine mammary carcinomas (mCAs) as well as benign canine mammary adenomas in a series of studies. Our results demonstrate strong stromal reprogramming in CMTs and identify high-grade molecular homology between human and canine CAS. Here, I aim to give a short background on the value of comparative oncology in general, and spontaneous CMT in particular. This will be followed by a concise review of the current knowledge of stromal reprogramming in both malignant canine mCA and benign adenoma. Finally, I will conclude with insights on highly conserved aspects of stromal reprogramming between CMT and human breast cancer that accentuate the relevance of CAS in CMT as a model for the human disease.

Epidermal growth factor receptor (EGFR) gene alteration and protein overexpression in Malaysian triple-negative breast cancer (TNBC) cohort

Background

Epidermal growth factor receptor (EGFR) is a member of the ErbB family of tyrosine kinase receptor proteins that plays important roles in tumour cell survival and proliferation. EGFR has been reported to be overexpressed in up to 78% of triple-negative breast cancer (TNBC) cases suggesting it as a potential therapeutic target. The clinical trials of anti-EGFR agents in breast cancer showed low response rates. However, a subgroup of patients demonstrated response to EGFR inhibitors highlighting the necessity to stratify patients, who might benefit from effective combination therapy that could include anti EGFR-agents. Population variability in EGFR expression warrants systematic evaluation in specific populations.

Purpose

To study EGFR alterations and expressions in a multi ethnic Malaysian TNBC patient cohort to determine the possibility of using anti-EGFR combinatorial therapy for this population.

Patients and methods

In this study, we evaluated 58 cases of Malaysian TNBC patient samples for EGFR gene copy number alteration and EGFR protein overexpression using fluorescence in-situ hybridization (FISH) and immunohistochemistry (IHC) methods, respectively.

Results

EGFR protein overexpression was observed in about 30% while 15.5% displayed high EGFR copy number including 5.17% gene amplification and over 10% high polysomy. There is a positive correlation between EGFR protein overexpression and gene copy number and over expression of EGFR is observed in ten out of the 48 low copy number cases (20.9%) without gene amplification.

Conclusion

This study provides the first glimpse of EGFR alterations and expressions in a multi ethnic Malaysian TNBC patient cohort emphasising the need for the nationwide large scale EGFR expression evaluation in Malaysia.

Ductal Carcinoma in Situ: Current Concepts in Biology, Imaging, and Treatment

Ductal carcinoma in situ (DCIS) of the breast is a group of heterogeneous epithelial proliferations confined to the milk ducts that nearly always present in asymptomatic women on breast cancer screening. A stage 0, preinvasive breast cancer, increased detection of DCIS was initially hailed as a means to prevent invasive breast cancer through surgical treatment with adjuvant radiation and/or endocrine therapies. However, controversy in the medical community has emerged in the past two decades that a fraction of DCIS represents overdiagnosis, leading to unnecessary treatments and resulting morbidity. The imaging hallmarks of DCIS include linearly or segmentally distributed calcifications on mammography or nonmass enhancement on breast MRI. Imaging features have been shown to reflect the biological heterogeneity of DCIS lesions, with recent studies indicating MRI may identify a greater fraction of higher-grade lesions than mammography does. There is strong interest in the surgical, imaging, and oncology communities to better align DCIS management with biology, which has resulted in trials of active surveillance and therapy that is less aggressive. However, risk stratification of DCIS remains imperfect, which has limited the development of precision therapy approaches matched to DCIS aggressiveness. Accordingly, there are opportunities for breast imaging radiologists to assist the oncology community by leveraging advanced imaging techniques to identify appropriate patients for the less aggressive DCIS treatments.

Glycosylation and its implications in breast cancer

Introduction: For decades, the role of glycans and glycoproteins in the progression of breast cancer and other cancers have been evaluated. Through extensive studies focused on elucidating the biological functions of glycosylation, researchers have been able to implicate alterations in these functions to tumor formation and metastasis. Areas covered: In this review, we summarize how changes in glycosylation are associated with tumorigenesis, with emphasis on breast cancers. An overview of the changes in N-linked and O-linked glycans associated with breast cancer tumors and biofluids are described. Recent advances in glycomics are emphasized in the context of continuing to decipher the glycosylation changes associated with breast cancer progression. Expert opinion: While changes in glycosylation have been studied in breast cancer for many years, the clinical relevance of these studies has been limited. This reflects the inherent biological and clinical heterogeneity of breast cancers. Glycomics analysis lags behind the advances in genomics and proteomics, but new approaches are emerging. A summary of known glycosylation changes associated with breast cancer is necessary to implement new findings in the context of clinical outcomes and therapeutic strategies. A better understanding of the dynamics of tumor and immune glycosylation is critical to improving emerging immunotherapeutic treatments.

Ampelopsin E Reduces the Invasiveness of the Triple Negative Breast Cancer Cell Line, MDA-MB-231

Breast cancer is the most common and the second leading cause of cancer-related deaths in women. It has two distinctive hallmarks: rapid abnormal growth and the ability to invade and metastasize. During metastasis, cancer cells are thought to form actin-rich protrusions, called invadopodia, which degrade the extracellular matrix. Current breast cancer treatments, particularly chemotherapy, comes with adverse effects like immunosuppression, resistance development and secondary tumour formation. Hence, naturally-occurring molecules claimed to be less toxic are being studied as new drug candidates. Ampelopsin E, a natural oligostilbene extracted from Dryobalanops species, has exhibited various pharmacological properties, including anticancer and anti-inflammatory activities. However, there is yet no scientific evidence of the effects of ampelopsin E towards metastasis. Scratch assay, transwell migration and invasion assays, invadopodia and gelatin degradation assays, and ELISA were used to determine the effects of ampelopsin E towards the invasiveness of MDA-MB-231 cells. Strikingly in this study, ampelopsin E was able to halt migration, transmigration and invasion in MDA-MB-231 cells by reducing formation of invadopodia and its degradation capability through significant reduction (p < 0.05) in expression levels of PDGF, MMP2, MMP9 and MMP14. In conclusion, ampelopsin E reduced the invasiveness of MDA-MB-231 cells and was proven to be a potential alternative in treating TNBC.

Risk stratification of ER-positive breast cancer patients: A multi-institutional validation and outcome study of the Rochester Modified Magee algorithm (RoMMa) and prediction of an Oncotype DX® recurrence score <26

The skyrocketing cost of health-care demands that we question when to use multigene assay testing in the planning of treatment for breast cancer patients. A previously published algorithmic model gave recommendations for which cases to send out for Oncotype DX^® (ODX) testing. This study is a multi-institutional validation of that algorithmic model in 620 additional estrogen receptor positive breast cancer cases, with outcome data on 310 cases, named in this study as the Rochester Modified Magee algorithm (RoMMa). RoMMa correctly predicted 85% (140/164) and 100% (17/17) of cases to have a low- or high-risk ODX recurrence score, respectively, consistent with the original publication. Applying our own risk stratification criteria, in patients who received appropriate hormonal therapy, only one of the 45 (2.0%) patients classified as low risk by our original algorithm have been associated with a breast cancer recurrence over 5-10 years of follow-up. Eight of 116 (7.0%) patients classified as low risk by ODX have been associated with a breast cancer recurrence with up to 11 years of follow-up. In addition, 524 of 537 (98%) cases from our total population (n = 903) with an average modified Magee score ≤18 had an ODX recurrence score <26. Patients with an average modified Magee score ≤18 or >30 may not need to be sent out for ODX testing. By avoiding these cases sending out for ODX testing, the potential cost savings to the health-care system in 2018 are estimated to have been over $100,000,000.

Identification of a gene signature for different stages of breast cancer development that could be used for early diagnosis and specific therapy

Breast cancer (BC) is a heterogeneous disease where the survival rate of patients decreases with progression of the disease. BC usually has a linear progression, classified into normal/benign, atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS), and invasive ductal carcinoma (IDC). This study aimed to identify gene signature for each of these subgroups. We performed human transcriptome array analysis on 5 patient samples from each Normal, ADH, IDC and DCIS and 2 replicates of MCF10A cell line representative of each subgroup. We identified SFRP1 and snoRNAs (especially SNORD115 and SNORD114) as the initial regulators of cancer progression, accompanied by significant changes in extracellular matrix organization. Tumor progression to the IDC stage showed upregulation of tumor promoting genes responsible for increased invasion, inflammation, survival in stress environment and metastasis. The gene signatures identified in this study could represent potential biomarkers for each subgroup of breast cancer progression, which could assist in early diagnosis of breast cancer progression as well as treatment interventions. Moreover, these gene signatures could serve in discovery of specific targeted therapies for each subgroup.