Current approaches and challenges in early detection of breast cancer recurrence

Differentiating Primary and Recurrent Lesions in Patients with a History of Breast Cancer: A Comprehensive Review

Breast cancer (BC) recurrence remains a concerning issue, requiring accurate identification and differentiation from primary lesions for optimal patient management. This comprehensive review aims to summarize and evaluate the current evidence on methods to distinguish primary breast tumors from recurrent lesions in patients with a history of BC. Also, we provide a comprehensive understanding of the different imaging techniques, including mammography, ultrasound, magnetic resonance imaging, and positron emission tomography, highlighting their diagnostic accuracy, limitations, and potential integration. In addition, the role of various biopsy modalities and molecular markers was explored. Furthermore, the potential role of liquid biopsy, circulating tumor cells, and circulating tumor DNA in differentiating between primary and recurrent BC was emphasized. Finally, it addresses emerging diagnostic modalities, such as radiomic analysis and artificial intelligence, which show promising potential in enhancing diagnostic accuracy. Through comprehensive analysis and review of the available literature, the current study provides an up-to-date understanding of the current state of knowledge, challenges, and future directions in accurately distinguishing between primary and recurrent breast lesions in patients with a history of BC.

Primary care provider-led cancer survivorship care in the first 5 years following initial cancer treatment: a scoping review of the barriers and solutions to implementation

PURPOSE

To synthesize the barriers to primary care provider (PCP)-led cancer survivorship care (≤ 5 years after initial cancer treatment) experienced by healthcare systems around the world, and to explore potential solutions that would succeed within a developed country.

METHODS

A scoping review of peer-reviewed articles and grey literature was conducted. Four electronic databases (Medline, Embase, Web of Science Core Collection, and Google Scholar) were searched for articles prior to April 2021.

RESULTS

Ninety-seven articles published across the globe (USA, Canada, Australia, European Union, and UK) met the review inclusion/exclusion criteria. The four most frequently discussed barriers to PCP-led survivorship care in healthcare systems were as follows: (1) insufficient communication between PCPs and cancer specialists, (2) limited PCP knowledge, (3) time restrictions for PCPs to provide comprehensive survivorship care, and (4) a lack of resources (e.g., survivorship care guidelines). Potential solutions to combat these barriers were as follows: (1) improving interdisciplinary communication, (2) bolstering PCP education, and (3) providing survivorship resources.

CONCLUSIONS

This scoping review identified and summarized key barriers and solutions to the provision of PCP-led cancer survivorship care. Importantly, the findings from this review provide insight and direction to guide optimization of cancer care practice within BC's healthcare system.

IMPLICATIONS FOR CANCER SURVIVORS

Optimizing the PCP-led survivorship care model will be a valuable contribution to the field of cancer survivorship care and will hopefully lead to more widespread use of this model, ultimately lessening the growing demand for cancer-specific care by cancer specialists.

Therapeutic Peptide RF16 Derived from CXCL8 Inhibits MDA-MB-231 Cell Invasion and Metastasis

Interleukin (IL)-8 plays a vital role in regulating inflammation and breast cancer formation by activating CXCR1/2. We previously designed an antagonist peptide, (RF16), to inhibits the activation of downstream signaling pathways by competing with IL-8 in binding to CXCR1/2, thereby inhibiting IL-8-induced chemoattractant monocyte binding. To evaluate the effect of the RF16 peptide on breast cancer progression, triple-negative MDA-MB-231 and ER-positive MCF-7 breast cancer cells were used to investigate whether RF16 can inhibit the IL-8-induced breast cancer metastasis. Using growth, proliferation, and invasiveness assays, the results revealed that RF16 reduced cell proliferation, migration, and invasiveness in MDA-MB-231 cells. The RF16 peptide also regulated the protein and mRNA expressions of epithelial-mesenchymal transition (EMT) markers in IL-8-stimulated MDA-MB-231 cells. It also inhibited downstream IL-8 signaling and the IL-8-induced inflammatory response via the mitogen-activated protein kinase (MAPK) and Phosphoinositide 3-kinase (PI3K) pathways. In the xenograft tumor mouse model, RF16 synergistically reinforces the antitumor efficacy of docetaxel by improving mouse survival and retarding tumor growth. Our results indicate that RF16 significantly inhibited IL-8-stimulated cell growth, migration, and invasion in MDA-MB-231 breast cancer cells by blocking the activation of p38 and AKT cascades. It indicated that the RF16 peptide may serve as a new supplementary drug for breast cancer.

Homogeneous Adaboost Ensemble Machine Learning Algorithms with Reduced Entropy on Balanced Data

Today's world faces a serious public health problem with cancer. One type of cancer that begins in the breast and spreads to other body areas is breast cancer (BC). Breast cancer is one of the most prevalent cancers that claim the lives of women. It is also becoming clearer that most cases of breast cancer are already advanced when they are brought to the doctor's attention by the patient. The patient may have the evident lesion removed, but the seeds have reached an advanced stage of development or the body's ability to resist them has weakened considerably, rendering them ineffective. Although it is still much more common in more developed nations, it is also quickly spreading to less developed countries. The motivation behind this study is to use an ensemble method for the prediction of BC, as an ensemble model aims to automatically manage the strengths and weaknesses of each of its separate models, resulting in the best decision being made overall. The main objective of this paper is to predict and classify breast cancer using Adaboost ensemble techniques. The weighted entropy is computed for the target column. Taking each attribute's weights results in the weighted entropy. Each class's likelihood is represented by the weights. The amount of information gained increases with a decrease in entropy. Both individual and homogeneous ensemble classifiers, created by mixing Adaboost with different single classifiers, have been used in this work. In order to deal with the class imbalance issue as well as noise, the synthetic minority over-sampling technique (SMOTE) was used as part of the data mining pre-processing. The suggested approach uses a decision tree (DT) and naive Bayes (NB), with Adaboost ensemble techniques. The experimental findings shown 97.95% accuracy for prediction using the Adaboost-random forest classifier.

Pharmacometabolomics reveals urinary diacetylspermine as a biomarker of doxorubicin effectiveness in triple negative breast cancer

Triple-negative breast cancer (TNBC) patients receive chemotherapy treatment, including doxorubicin, due to the lack of targeted therapies. Drug resistance is a major cause of treatment failure in TNBC and therefore, there is a need to identify biomarkers that determine effective drug response. A pharmacometabolomics study was performed using doxorubicin sensitive and resistant TNBC patient-derived xenograft (PDX) models to detect urinary metabolic biomarkers of treatment effectiveness. Evaluation of metabolite production was assessed by directly studying tumor levels in TNBC-PDX mice and human subjects. Metabolic flux leading to biomarker production was determined using stable isotope-labeled tracers in TNBC-PDX ex vivo tissue slices. Findings were validated in 12-h urine samples from control (n = 200), ER+/PR+ (n = 200), ER+/PR+/HER2+ (n = 36), HER2+ (n = 81) and TNBC (n = 200) subjects. Diacetylspermine was identified as a urine metabolite that robustly changed in response to effective doxorubicin treatment, which persisted after the final dose. Urine diacetylspermine was produced by the tumor and correlated with tumor volume. Ex vivo tumor slices revealed that doxorubicin directly increases diacetylspermine production by increasing tumor spermidine/spermine N¹-acetyltransferase 1 expression and activity, which was corroborated by elevated polyamine flux. In breast cancer patients, tumor diacetylspermine was elevated compared to matched non-cancerous tissue and increased in HER2+ and TNBC compared to ER+ subtypes. Urine diacetylspermine was associated with breast cancer tumor volume and poor tumor grade. This study describes a pharmacometabolomics strategy for identifying cancer metabolic biomarkers that indicate drug response. Our findings characterize urine diacetylspermine as a non-invasive biomarker of doxorubicin effectiveness in TNBC.

Mode of Detection of Second Events in Routine Surveillance of Early Stage Breast Cancer Patients

INTRODUCTION

NCCN and ASCO guidelines recommend breast cancer (BC) follow-up to include clinical breast examination (CBE) every 6 months and annual mammography (AM) for 5 years. Given limited data to support CBE, we evaluated the modes of detection (MOD) of BC-events in a contemporary practice.

METHODS

We conducted a retrospective review of registry patients with early stage BC (DCIS, Stage I or II) diagnosed between 2010 and 2015 with at least 5 years of follow-up. Second events were defined as malignant (contralateral primary, ipsilateral breast tumor recurrence (IBTR), chest wall recurrence, regional node recurrence or distant relapse) or benign. MOD was categorized as patient complaint, clinical examination or breast imaging.

RESULTS

Sixty-three of 351 BC patients experienced second events. 15 had BC malignant events, including 4 distant disease, 5 contralateral primary, and 3 IBTR. 7/8 of IBTR and contralateral primary BC were AM detected. Patient complaints identified 4/4 distant relapses. Clinical exam identified 2/2 chest wall recurrences in post-mastectomy patients.

CONCLUSIONS

Only 2.8% (10/351) of early stage BC patients experienced recurrence during 5 years of follow-up. AM was the predominate MOD of both IBTR and new contralateral primary following breast conserving therapy. Patient complaints prompted evaluation for distant disease. Provider CBE was MOD in only 2/351, 0.6% 95% CI (2.1%-0.1%) of patients as chest wall recurrences postmastectomy. Given modern enhancements to imaging and lower recurrence rates, this data encourages the reassessment of guidelines for every 6-month CBE and provides basis to study telehealth in survivorship care.

Enhanced Detection of Desmoplasia by Targeted Delivery of Iron Oxide Nanoparticles to the Tumour-Specific Extracellular Matrix

Diagnostic imaging of aggressive cancer with a high stroma content may benefit from the use of imaging contrast agents targeted with peptides that have high binding affinity to the extracellular matrix (ECM). In this study, we report the use of superparamagnetic iron-oxide nanoparticles (IO-NP) conjugated to a nonapeptide, CSGRRSSKC (CSG), which specifically binds to the laminin-nidogen-1 complex in tumours. We show that CSG-IO-NP accumulate in tumours, predominantly in the tumour ECM, following intravenous injection into a murine model of pancreatic neuroendocrine tumour (PNET). In contrast, a control untargeted IO-NP consistently show poor tumour uptake, and IO-NP conjugated to a pentapeptide, CREKA that bind fibrin clots in blood vessels show restricted uptake in the angiogenic vessels of the tumours. CSG-IO-NP show three-fold higher intratumoral accumulation compared to CREKA-IO-NP. Magnetic resonance imaging (MRI) T₂-weighted scans and T₂ relaxation times indicate significant uptake of CSG-IO-NP irrespective of tumour size, whereas the uptake of CREKA-IO-NP is only consistent in small tumours of less than 3 mm in diameter. Larger tumours with significantly reduced tumour blood vessels show a lack of CREKA-IO-NP uptake. Our data suggest CSG-IO-NP are particularly useful for detecting stroma in early and advanced solid tumours.

Diagnostics and Therapeutics in Targeting HER2 Breast Cancer: A Novel Approach

Breast cancer is one of the most commonly occurring cancers in women globally and is the primary cause of cancer mortality in females. BC is highly heterogeneous with various phenotypic expressions. The overexpression of HER2 is responsible for 15-30% of all invasive BC and is strongly associated with malignant behaviours, poor prognosis and decline in overall survival. Molecular imaging offers advantages over conventional imaging modalities, as it provides more sensitive and specific detection of tumours, as these techniques measure the biological and physiological processes at the cellular level to visualise the disease. Early detection and diagnosis of BC is crucial to improving clinical outcomes and prognosis. While HER2-specific antibodies and nanobodies may improve the sensitivity and specificity of molecular imaging, the radioisotope conjugation process may interfere with and may compromise their binding functionalities. Aptamers are single-stranded oligonucleotides capable of targeting biomarkers with remarkable binding specificity and affinity. Aptamers can be functionalised with radioisotopes without compromising target specificity. The attachment of different radioisotopes can determine the aptamer's functionality in the treatment of HER2(+) BC. Several HER2 aptamers and investigations of them have been described and evaluated in this paper. We also provide recommendations for future studies with HER2 aptamers to target HER2(+) BC.

Breast ultrasound in breast cancer surveillance; incremental cancers found at what cost?

Purpose

To determine the diagnostic parameters of breast ultrasound (US) in the setting of routine radiological surveillance after a diagnosis of breast cancer and evaluate costs of the inclusion of breast US as well as any survival benefit of US detected cases of recurrence in surveillance.

Methods

622 patients underwent breast cancer surgery and follow up at Austin Health from July 2009 to December 2015. Retrospective data analysis was performed to determine; diagnostic parameters, financial costs of US and survival outcomes of US detected cases of recurrence.

Results

Patients underwent 1–9 years of breast cancer surveillance, with a median of 4.24 years. 390 (62.7%) patients underwent additional breast US surveillance to mammography. 232 (38.3%) fit criteria for use of additional breast US. 199 abnormal imaging episodes occurred, leading to 16 screen detected-cases of locoregional recurrence. US alone generated 107 abnormal images and found 9 cancers. US had a sensitivity of 44.1%, specificity of 95.2% and positive predictive value of 11.7% in comparison to mammography; 20.6%, 97.4% and 9.9% respectively. US had a biopsy rate of 4.0% and lead to an incremental cancer detection rate of 0.38%. The cost of incremental cancer found was $31,463.72 AUD. Survival outcomes based on method of detection of recurrence were insignificant (p value = 0.71).

Conclusions

Breast US has a sensitivity of 44.1% and detected seven recurrences that were mammographically occult. Breast US has a similar PPV to mammography in surveillance. Breast US generated considerable biopsy rates and costs. Survival analysis was not able to detect any benefit of US detected cases of recurrence.

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Breast ultrasound in asymptomatic surveillance after breast cancer surgery was found to have a sensitivity of 44.1%.

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Breast ultrasound detected 7 recurrences in 390 patients who did not meet criteria for adjunct breast US and had normal mammography

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Breast ultrasound generated 26 additional biopsies per 1000 US compared to mammography in surveillance, creating considerablecosts.

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Cancer detection by breast US alone did not lead to statistically significant survival benefit over mammography.

Use of real-world data to study health services utilisation and comorbidities in long-term breast cancer survivors (the SURBCAN study): study protocol for a longitudinal population-based cohort study

INTRODUCTION

Breast cancer has become a chronic disease due to survival improvement and the need to monitor the side effects of treatment and the disease itself. The aim of the SURBCAN study is to describe comorbidity, healthcare services use and adherence to preventive recommendations in long-term breast cancer survivors and to compare them with those in women without this diagnosis in order to improve and adapt the care response to this group of survivors.

METHODS AND ANALYSIS

Population-based retrospective cohort study using real-world data from cancer registries and linked electronic medical records in five Spanish regions. Long-term breast cancer survivors diagnosed between 2000 and 2006 will be identified and matched by age and administrative health area with women without this diagnosis. Sociodemographic and clinical variables including comorbidities and variables on the use of health services between 2012 and 2016 will be obtained from databases in primary and hospital care. Health services use will be assessed through the annual number of visits to primary care professionals and to specialists and through annual imaging and laboratory tests. Factors associated with healthcare utilisation and comorbidities will be analysed using multilevel logistic regression models. Recruitment started in December 2018.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Parc de Salut Mar. The results of the study will be published in a peer-reviewed journal and will be presented at national and international scientific conferences and at patient associations.

TRIAL REGISTRATION NUMBER

This protocol is registered in Clinical Trials.gov (identifier: NCT03846999).

Efficacy of Affibody-Based Ultrasound Molecular Imaging of Vascular B7-H3 for Breast Cancer Detection

PURPOSE

Human B7-H3 (hB7-H3) is a promising molecular imaging target differentially expressed on the neovasculature of breast cancer and has been validated for preclinical ultrasound (US) imaging with anti-B7-H3-antibody-functionalized microbubbles (MB). However, smaller ligands such as affibodies (ABY) are more suitable for the design of clinical-grade targeted MB.

EXPERIMENTAL DESIGN

Binding of ABY_B7-H3 was confirmed with soluble and cell-surface B7-H3 by flow cytometry. MB were functionalized with ABY_B7-H3 or anti-B7-H3-antibody (Ab_B7-H3). Control and targeted MB were tested for binding to hB7-H3-expressing cells (MS1_hB7-H3) under shear stress conditions. US imaging was performed with MB_ABY-B7-H3 in an orthotopic mouse model of human MDA-MB-231 coimplanted with MS1_hB7-H3 or control MS1_WT cells and a transgenic mouse model of breast cancer development.

RESULTS

ABY_B7-H3 specifically binds to MS1_hB7-H3 and murine-B7-H3-expressing monocytes. MB_ABY-B7-H3 (8.5 ± 1.4 MB/cell) and MB_Ab-B7-H3 (9.8 ± 1.3 MB/cell) showed significantly higher (P < 0.0001) binding to the MS1_hB7-H3 cells compared with control MB_Non-targeted (0.5 ± 0.1 MB/cell) under shear stress conditions. In vivo, MB_ABY-B7-H3 produced significantly higher (P < 0.04) imaging signal in orthotopic tumors coengrafted with MS1_hB7-H3 (8.4 ± 3.3 a.u.) compared with tumors with MS1_WT cells (1.4 ± 1.0 a.u.). In the transgenic mouse tumors, MB_ABY-B7-H3 (9.6 ± 2.0 a.u.) produced higher (P < 0.0002) imaging signal compared with MB_Non-targeted (1.3 ± 0.3 a.u.), whereas MB_ABY-B7-H3 signal in normal mammary glands and tumors with B7-H3 blocking significantly reduced (P < 0.02) imaging signal.

CONCLUSIONS

MB_ABY-B7-H3 enhances B7-H3 molecular signal in breast tumors, improving cancer detection, while offering the advantages of a small size ligand and easier production for clinical imaging.

Prognostic Significance of TWIST1, CD24, CD44, and ALDH1 Transcript Quantification in EpCAM-Positive Circulating Tumor Cells from Early Stage Breast Cancer Patients

(1) Background: The aim of the study was to evaluate the prognostic significance of EMT-associated (TWIST1) and stem-cell (SC) transcript (CD24, CD44, ALDH1) quantification in EpCAM+ circulating tumor cells (CTCs) of early breast cancer patients. (2) Methods: 100 early stage breast cancer patients and 19 healthy donors were enrolled in the study. CD24, CD44, and ALDH1 transcripts of EpCAM⁺ cells were quantified using a novel highly sensitive and specific quadraplex RT-qPCR, while TWIST1 transcripts were quantified by single RT-qPCR. All patients were followed up for more than 5 years. (3) Results: A significant positive correlation between overexpression of TWIST1 and CD24^−/low/CD44^high profile was found. Kaplan–Meier analysis revealed that the ER/PR-negative (HR-) patients and those patients with more than 3 positive lymph nodes that overexpressed TWIST1 in EpCAM⁺ cells had a significant lower DFI (log rank test; p < 0.001, p < 0.001) and OS (log rank test; p = 0.006, p < 0.001). Univariate and multivariate analysis also revealed the prognostic value of TWIST1 overexpression and CD24^−/low/CD44^high and CD24^−/low/ALDH1^high profile for both DFI and OS. (4) Conclusions: Detection of TWIST1 overexpression and stem-cell (CD24, CD44, ALDH1) transcripts in EpCAM⁺ CTCs provides prognostic information in early stage breast cancer patients.

Predicting the risk of locoregional recurrence after early breast cancer: an external validation of the Dutch INFLUENCE-nomogram with clinical cancer registry data from Germany

Purpose

Follow-up after breast cancer treatment aims for an early detection of locoregional breast cancer recurrences (LRR) to improve the patients’ outcome. By estimating individual’s 5-year recurrence-risks, the Dutch INFLUENCE-nomogram can assist health professionals and patients in developing personalized risk-based follow-up pathways. The objective of this study is to validate the prediction tool on non-Dutch patients.

Material and methods

Data for this external validation derive from a large clinical cancer registry in southern Germany, covering a population of 1.1 million. Patients with curative resection of early-stage breast cancer, diagnosed between 2000 and 2012, were included in the analysis (n = 6520). For each of them, an individual LRR-risk was estimated by the INFLUENCE-nomogram. Its predictive ability was tested by comparing estimated and observed LRR-probabilities using the Hosmer–Lemeshow goodness-of-fit test and C-statistics.

Results

In the German validation-cohort, 2.8% of the patients developed an LRR within 5 years after primary surgery (n = 184). While the INFLUENCE-nomogram generally underestimates the actual LRR-risk of the German patients (p < 0.001), its discriminative ability is comparable to the one observed in the original Dutch modeling-cohort (C-statistic German validation-cohort: 0.73, CI 0.69–0.77 vs. C-statistic Dutch modeling-cohort: 0.71, CI 0.69–0.73). Similar results were obtained in most of the subgroup analyses stratified by age, type of surgery and intrinsic biological subtypes.

Conclusion

The outcomes of this external validation underline the generalizability of the INFLUENCE-nomogram beyond the Dutch population. The model performance could be enhanced in future by incorporating additional risk factors for LRR.

Overview of the genetic basis toward early detection of breast cancer

Cancer is a socioeconomical burden in any nation. Out of that, breast cancer is identified as the most common malignancy worldwide among women irrespective of age. As women are an important segment in a community, the weakening of their strength toward the development of a nation is a critical problem in each nation. In this review, it was aimed to discuss the characteristics of cancer genome, cancer genetics, and cancer epigenetics in general and then focus on discussing both genetic and nongenetic factors responsible for the predisposition of breast cancer in humans. More emphasis was placed on genes responsible for the early onset of the disease and which can be used as genetic tools in the identification of the disease at an early stage. Then the context of genetic involvement toward the breast cancer occurrence before age of 40 years was highlighted accordingly. In addition to genetic testing, the review paid adequate attention to mention novel liquid biopsy techniques and other clinical, laboratory, and radiologic assessments. These techniques can be used in early detection and recurrence as well as the surveillance of the patients after primary therapies.

Screening mammography for second breast cancers in women with history of early-stage breast cancer: factors and causes associated with non-detection

Background

The aim of our study was to identify the factors and causes associated with non-detection for second breast cancers on screening mammography in women with a personal history of early-stage breast cancer.

Methods

Between January 2000 and December 2008, 7976 women with early-stage breast cancer underwent breast surgery in our institution. The inclusion criteria of our study were patients who had: (a) subsequent in-breast recurrence, (b) surveillance mammography within 1 year before recurrence. Retrospective analysis of mammography was performed. Non-detection was defined as second breast cancers that were not visible on screening mammography. Imaging features, demographics, primary breast cancer (PBC) characteristics, and clinical features were evaluated to determine its association with non-detection. Univariate and multivariate logistic regression analyses were also performed to identify the factors related to non-detection.

Results

We identified 188 patients that met the criteria. Among them, 39% of patients showed non-detection (n = 74). Of the 74 patients with non-detection, 53 (72%) were classified as having no detectable mammographic abnormality (i.e., true negative) due to overlapping dense breast tissue (n = 32), obscured by postoperative scar (n = 12) or difficult anatomic location / poor positioning (n = 9). The remaining 21 patients were categorized as having subtle findings (n = 11) or missed cancer (n = 10). Non-detection for second breast cancers were significantly associated with mammographic breast density (p = 0.001, OR = 2.959) and detectability of PBC on mammography (p = 0.011, OR = 3.013).

Conclusion

Non-detection of second breast cancer in women with a personal history of early-stage breast cancer were associated with mammographic dense breast and lower detectability of PBC on mammography.

Loss of RBMS3 Confers Platinum Resistance in Epithelial Ovarian Cancer via Activation of miR-126-5p/β-catenin/CBP signaling

PURPOSE

The development of resistance to platinum-based chemotherapy remains the unsurmountable obstacle in cancer treatment and consequently leads to tumor relapse. This study aims to investigate the mechanism by which loss of RBMS3 induced chemoresistance in epithelial ovarian cancer (EOC).

EXPERIMENTAL DESIGN

FISH and IHC were used to determine deletion frequency and expression of RBMS3 in 15 clinical EOC tissues and 150 clinicopathologically characterized EOC specimens. The effects of RBMS3 deletion and CBP/β-catenin antagonist PRI-724 in chemoresistance were examined by clone formation and Annexin V assays in vitro, and by intraperitoneal tumor model in vivo. The mechanism by which RBMS3 loss sustained activation of miR-126-5p/β-catenin/CBP signaling and the effects of RBMS3 and miR-126-5p competitively regulating DKK3, AXIN1, BACH1, and NFAT5 was explored using CLIP-seq, RIP, electrophoretic mobility shift, and immunoblotting and immunofluorescence assays.

RESULTS

Loss of RBMS3 in EOC was correlated with the overall and relapse-free survival. Genetic ablation of RBMS3 significantly enhanced, whereas restoration of RBMS3 reduced, the chemoresistance ability of EOC cells both in vitro and in vivo. RBMS3 inhibited β-catenin/CBP signaling through directly associating with and stabilizing multiple negative regulators, including DKK3, AXIN1, BACH1, and NFAT5, via competitively preventing the miR-126-5p-mediated repression of these transcripts. Importantly, cotherapy of CBP/β-catenin antagonist PRI-724 induced sensitization of RBMS3-deleted EOC to platinum therapy.

CONCLUSIONS

Our results demonstrate that genetic ablation of RBMS3 contributes to chemoresistance and PRI-724 may serve as a potential tailored treatment for patients with RBMS3-deleted EOC.

Analysis of patient-detected breast cancer recurrence

BACKGROUND

After primary surgical resection, breast cancer survivors regularly undergo surveillance using multiple modalities to detect recurrences.

OBJECTIVE

The goal of this study was to determine how breast cancer recurrences were detected in our sample population of breast cancer survivors. We hypothesize that the majority of recurrences are patient-detected.

METHODS

This was a retrospective observational study evaluating patients with a detected breast cancer recurrence between 2010 and 2015. Patients were analyzed by initial detection modality (patient versus clinician versus imaging). Other variables of interest included insurance status, ambulation capability, living situation, age at diagnosis and recurrence, and time to recurrence. Statistical methods included chi-square tests, log-rank tests, and analysis of variance.

RESULTS

115 patients were identified with a recurrence (mean age 61 years). 88 (77%) recurrences were patient-detected, 14 (12%) were detected by imaging, and 13 (11%) were clinician-detected (chi-square goodness of fit test p < 0.001). Median time to recurrence was 4 years in the patient-detection group compared to 3 for the clinician group and 2 for imaging detection (log-rank test p = 0.01).

CONCLUSION

While the majority of recurrences were patient-detected, these were detected later and at a more advanced clinical stage. This could represent an opportunity to enhance outcomes by empowering patient detection strategies.

Investigation of adhesive interactions in the specific targeting of Triptorelin-conjugated PEG-coated magnetite nanoparticles to breast cancer cells

The understanding of adhesive interaction at the nanoscale between functionalized nanoparticles and biological cells is of great importance to develop effective theranostic nanocarriers for targeted cancer therapy. Here, we report a combination of experimental and computational approaches to evaluate the adhesion between Triptorelin (a Luteinizing Hormone-Releasing Hormone (LHRH) agonist)-conjugated poly-(ethylene glycol) (PEG)-coated magnetite nanoparticles (Triptorelin-MNPs) and breast cells. The adhesion forces between Triptorelin-MNPs and normal/cancerous breast cells are obtained using atomic force microscopy. The corresponding work of adhesion is then estimated using Johnson-Kendall-Roberts model. Our results demonstrate that Triptorelin-MNPs have a fourteen-fold greater work of adhesion to breast cancer cells than to normal breast cells. In addition, the work of adhesion between Triptorelin-MNPs and breast cancer cells is found to be three times more than that between unmodified MNPs and breast cancer cells. Hence, the experimental observation indicates that Triptorelin ligands facilitate the specific targeting of breast cancer cells. Furthermore, molecular dynamics simulations are performed to investigate the molecular origins of the adhesive interactions. The simulations reveal that the interactions between molecules (e.g. Triptorelin and PEG) and LHRH receptors are dominated by van der Waals energies, while the interactions of these molecules with cell membrane are dominated by electrostatic interactions. Moreover, both experimental and computational results reveal that PEG serves as an effective coating that enhances adhesive interactions to breast cancer cells that over-express LHRH receptors, while reduces the adhesion to normal breast cells. Our results highlight the potential to develop Triptorelin-MNPs into tumor-specific MRI contrast agents and drug carriers.

STATEMENT OF SIGNIFICANCE

Systematic investigation of adhesive interactions between functionalized nanoparticles and cancer cells is of great importance in developing effective theranostic nanocarriers for targeted cancer therapy. Herein, we use a combination of atomic force microscopy technique and molecular dynamics simulations approach to explore the adhesive interactions at the nanoscale between Triptorelin-conjugated polyethylene glycol (PEG)-coated magnetite nanoparticles and normal/cancerous breast cells. This study characterizes and quantifies the work of adhesion, as well as adhesion forces, at the nanocarrier/cell interfaces, unravels the molecular origins of adhesive interactions and highlights the effectiveness of PEG coatings and Triptorelin ligands in the specific targeting of breast cancer cells. Our findings expand the fundamental understanding of nanoparticle/cell adhesion and provide guidelines for the design of more rational nanocarriers.

Longitudinal autoantibody responses against tumor-associated antigens decrease in breast cancer patients according to treatment modality

BACKGROUND

Metastatic breast cancer (BCa) is most often diagnosed months after completion of treatment of the primary tumor when a patient reports physical symptoms. Besides a physical examination, no other alternative recurrence screening method is recommended for routine follow-up care. Detection of autoantibodies against tumor-associated antigens (TAAs) has demonstrated promise for distinguishing healthy women from patients diagnosed with primary BCa. However, it is unknown what changes occur to patient autoantibody levels during and after treatment.

METHODS

Three serial blood draws were collected from 200 BCa patients: before treatment, 6 and 12 months after surgery. Patients were categorized according to treatment regimen, including surgery, chemotherapy, radiation, trastuzumab and hormonal therapies. The longitudinal samples were assayed for autoantibody responses against 32 conformation-carrying TAAs using a Luminex multiplex bead assay.

RESULTS

The treatment modality groups that had the greatest decrease in autoantibody response levels were radiation + hormonal therapy; radiation + chemotherapy; and radiation + hormonal therapy + chemotherapy. For these three treatment groups, autoantibody responses against 9 TAAs (A1AT, ANGPTL4, CAPC, CST2, DKK1, GFRA1, GRN, LGALS3 and LRP10) were significantly reduced at 12 months after surgery compared to before treatment. One TAA, GRP78, had a significantly increased autoantibody response after 12 months.

CONCLUSIONS

Single treatment regimens alone did not significantly alter autoantibodies levels against the studied TAAs. Radiation treatment was the common denominator of the three most affected groups for significant changes in autoantibody response levels.

A Low-Cost, Low-Skill Model for Efficient Breast Cancer Screening in Low Resource Rural Settings of a Developing Country

Objective

To suggest a low-cost, easily-operable, non-invasive imaging modality for cancer detection in rural settings.

Method

A total of 212 cases with palpable breast masses aged 18 - 65 years were enrolled and underwent thorough clinical, mammographic, and ultrasonographic (USG) evaluation. Imaging findings were reported using the American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS®) criteria. The findings were confirmed histopathologically. Data were analyzed using the Chi-square test.

Results

The malignancy rate was 35.8% (n = 76). On mammography, lesions size, margins, shape, calcification, and distorted arch/skin thickening were significantly associated with malignancy. On USG, the number of nodules, shape, margins, echotexture, posterior wall echo, through transmission changes, distorted arch/skin thickening, microlobulation, duct extension, and height/width ratio were significantly associated with malignancy. Independently, mammography and USG had a sensitivity of 78.1% and 80.3%, respectively, and a specificity of 83.3% and 89.0%, respectively. Using a positive result of either study as the criteria, the sensitivity was 97.4% and the specificity was 80.1%.

Conclusion

The combined use of mammography and USG provides high sensitivity and specificity, thus showing that a combination of two can be used as a screening tool for use in low resource rural settings.

A tumor specific antibody to aid breast cancer screening in women with dense breast tissue

Screening for breast cancer has predominantly been done using mammography. Unfortunately, mammograms miss 50% cancers in women with dense breast tissue. Multi-modal screenings offer the best chance of enhancing breast cancer screening effectiveness. We evaluated the use of TAB004, an antibody that recognizes the tumor form of the glycoprotein MUC1 (tMUC1), to aid early detection of breast cancer. Our experimental approach was to follow tMUC1 from the tissue into circulation. We found that 95% of human breast cancer tissues across all subtypes stained positive for TAB004. In breast cancer cell lines, we showed that the amount of tMUC1 released from tumor cells is proportional to the cell's tMUC1 expression level. Finally, we showed that TAB004 can be used to assess circulating tMUC1 levels, which when monitored in the context of cancer immunoediting, can aid earlier diagnosis of breast cancer regardless of breast tissue density. In a blinded pilot study with banked serial samples, tMUC1 levels increased significantly up to 2 years before diagnosis. Inclusion of tMUC1 monitoring as part of a multi-modal screening strategy may lead to earlier stage diagnosis of women whose cancers are missed by mammography.

Engineering hepatitis B virus core particles for targeting HER2 receptors in vitro and in vivo

Hepatitis B Virus core (HBc) particles have been studied for their potential as drug delivery vehicles for cancer therapy. HBc particles are hollow nano-particles of 30–34 nm diameter and 7 nm thick envelopes, consisting of 180–240 units of 21 kDa core monomers. They have the capacity to assemble/dis-assemble in a controlled manner allowing encapsulation of various drugs and other biomolecules. Moreover, other functional motifs, i.e. receptors, receptor binding sequences, peptides and proteins can be expressed. This study focuses on the development of genetically modified HBc particles to specifically recognise and target human epidermal growth factor receptor-2 (HER2)-expressing cancer cells, in vitro and in vivo, for future cancer therapy. The non-specific binding capacity of wild type HBc particles was reduced by genetic deletion of the sequence encoding arginine-rich domains. A specific HER2-targeting was achieved by expressing the Z_HER2 affibodies on the HBc particles surface. In vitro studies showed specific uptake of Z_HER2-ΔHBc particles in HER2 expressing cancer cells. In vivo studies confirmed positive uptake of Z_HER2-ΔHBc particles in HER2-expressing tumours, compared to non-targeted ΔHBc particles in intraperitoneal tumour-bearing mice models. The present results highlight the potential of these nanocarriers in targeting HER2-positive metastatic abdominal cancer following intra-peritoneal administration.

Clinical surveillance compared with clinical and magnetic resonance imaging surveillance for brain metastasis: a feasibility survey

INTRODUCTION

After stereotactic radiosurgery (srs) for brain metastases, patients are routinely monitored with magnetic resonance imaging (mri). The high rate of new brain metastases after srs treatment alone might not be as concerning with modern mri and target localization treatment. Intensive surveillance might induce anxiety, lowering the patient's quality of life (qol). The present work is the feasibility component of a prospective study evaluating the role of surveillance mri on qol in patients with limited (1-3) brain metastases.

METHODS

Patients with limited brain metastases treated with srs alone, an Eastern Cooperative Oncology Group performance status of 2 or less, and documented stability in treated lesions, with no new lesions seen on mri at weeks 6-10 after srs, were eligible. All were asked about their interest in participating in the control (mri and clinical surveillance) or the experimental arm (symptom-directed mri and clinical surveillance). If 33% or more agreed to participate in the experimental arm, it would be considered feasible to conduct the prospective study.

RESULTS

From November 2014 to July 2015, 45% of patients (10 of 22) agreed to participate in the experimental arm. Subgroup analyses found that the decision to participate has no statistically significant association with time of presentation (p = 0.696), display of symptoms (p = 0.840), age (p = 0.135), or number of lesions (p = 0.171).

CONCLUSIONS

Results show that it is feasible to conduct the prospective cohort study. Because of the small sample size, we are limited in the conclusions able to be drawn in the subgroup analyses. However, the future study would allow for a better understanding of the attitudes of patients toward mri and its effect on qol.

c-Met PET Imaging Detects Early-Stage Locoregional Recurrence of Basal-Like Breast Cancer

Locoregional recurrence of breast cancer poses significant clinical problems because of frequent inoperability once the chest wall is involved. Early detection of recurrence by molecular imaging agents against therapeutically targetable receptors, such as c-Met, would be of potential benefit. The aim of this study was to assess (18)F-AH113804, a peptide-based molecular imaging agent with high affinity for human c-Met, for the detection of early-stage locoregional recurrence in a human basal-like breast cancer model, HCC1954.

METHODS

HCC1954 tumor-bearing xenograft models were established, and (18)F-AH113804 was administered. Distribution of radioactivity was determined via PET at 60 min after radiotracer injection. PET and CT images were acquired 10 d after tumor inoculation, to establish baseline distribution and uptake, and then on selected days after surgical tumor resection. CT images and caliper were used to determine the tumor volume. Radiotracer uptake was assessed by (18)F-AH113804 PET imaging. c-Met expression was assessed by immunofluorescence imaging of tumor samples and correlated with (18)F-AH113804 PET imaging results.

RESULTS

Baseline uptake of (18)F-AH113804, determined in tumor-bearing animals after 10 d, was approximately 2-fold higher in the tumor than in muscle tissue or the contralateral mammary fat pad. The tumor growth rate, determined from CT images, was comparable between the animals with recurrent tumors, with detection of tumors of low volume (<10 mm(3)) only possible by day 20 after tumor resection. (18)F-AH113804 PET detected local tumor recurrence as early as 6 d after surgery in the recurrent tumor-bearing animals and exhibited significantly higher (18)F-AH113804 uptake (in comparison to mammary fatty tissue), with a target-to-background (muscle) ratio of approximately 3:1 (P < 0.01). The c-Met expression of individual resected tumor samples, determined by immunofluorescence, correlated with the respective (18)F-AH113804 imaging signals (r = 0.82, P < 0.05).

CONCLUSION

(18)F-AH113804 PET provides a new diagnostic tool for the detection of c-Met-expressing primary tumor and has potential utility for the detection of locoregional recurrence from an early stage.

Nelfinavir targets multiple drug resistance mechanisms to increase the efficacy of doxorubicin in MCF-7/Dox breast cancer cells

Development of multidrug resistance (MDR) remains a significant problem in cancer chemotherapy and underscores the importance of using chemosensitizers. Well known MDR mechanisms include: (i) upregulation of drug-efflux; (ii) increased signaling via AKT; and (iii) decreased apoptosis. Therefore, chemosensitizers should target multiple resistance mechanisms. We investigated the efficacy of nelfinavir (NFV), a clinically approved anti-HIV drug, in increasing doxorubicin (DOX) toxicity in a MDR breast cancer cell line, MCF-7/Dox. As compared to parental MCF-7 cells, the MCF-7/Dox were 15-20 fold more resistant to DOX-induced cytotoxicity at 48 h post-exposure (DOX IC50 = 1.8 μM vs. 32.4 μM). Coexposures to NFV could significantly (p < 0.05) decrease DOX-IC50 in MCF-7/Dox cells. Multiple exposures to physiologic concentrations of NFV (2.25 μM or 6.75 μM) decreased DOX-IC50 by 21-fold and 50-fold, respectively. Interestingly, although single exposure to NFV transiently induced P-glycoprotein (P-gp) levels, multiple treatments with NFV inhibited both P-gp expression and efflux function, which increased intracellular DOX concentrations. Single exposure to NFV augmented the markers of cell-survival (AKT) and autophagy (LC3-II), whereas multiple exposures enabled suppression of both total AKT (t-AKT) and insulin like growth factor-1 (IGF-1)-induced phosphorylated AKT (p-AKT) levels. Multiple exposures to NFV also resulted in increased unfolded protein response (UPR) transducers, e.g. Grp78, p-PERK, p-eIF2α, and ATF-4; and endoplasmic reticulum (ER) stress induced death sensors, e.g. CHOP & TRIB-3. Multiple exposures to NFV also abrogated the mitogenic effects of IGF-1. In mice carrying MCF-7/Dox tumor xenografts, intraperitoneal (i.p.) injection of NFV (20 mg/kg/day) and DOX (2 mg/kg/twice/wk) decreased tumor growth more significantly (p < 0.01) than either agent alone. Immunohistochemical (IHC) analysis revealed decreased p-AKT and Ki-67 levels. Thus, NFV overcomes MDR in breast cancer cells and should be tested as an adjunct to chemotherapy.