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Hyperpolarized 13C-MRI is an emerging tool for probing tissue metabolism by measuring 13C-label exchange between intravenously injected hyperpolarized [1–13C]pyruvate and endogenous tissue lactate. Here, we demonstrate that hyperpolarized 13C-MRI can be used to detect early response to neoadjuvant therapy in breast cancer. Seven patients underwent multiparametric 1H-MRI and hyperpolarized 13C-MRI before and 7–11 days after commencing treatment. An increase in the lactate-to-pyruvate ratio of approximately 20% identified three patients who, following 5–6 cycles of treatment, showed pathological complete response. This ratio correlated with gene expression of the pyruvate transporter MCT1 and lactate dehydrogenase A (LDHA), the enzyme catalyzing label exchange between pyruvate and lactate. Analysis of approximately 2,000 breast tumors showed that overexpression of LDHA and the hypoxia marker CAIX was associated with reduced relapse-free and overall survival. Hyperpolarized 13C-MRI represents a promising method for monitoring very early treatment response in breast cancer and has demonstrated prognostic potential.Significance:Hyperpolarized carbon-13 MRI allows response assessment in patients with breast cancer after 7–11 days of neoadjuvant chemotherapy and outperformed state-of-the-art and research quantitative proton MRI techniques.

INTRODUCTION: Increasingly we are dealing with more and more impalpable breast lesions thanks to screening programmes, chemotherapy and in situ disease. There are various techniques already employed for assisting in surgery for impalpable lesions such as radioactive and magnetic markers. All of these have limitations and are only useful in surgery. Ultrasound can be used in clinic and theatre to locate tumours and sonographically visible markers. In our experience in the Cambridge breast unit we have found it is more satisfactory to use guidewires that are intraoperatively or preoperatively placed using ultrasound guidance. This allows for direct approach to the lesion at the same time limiting the dissection and volume of resection. The guidewire allows tactile feedback and helps with precision and accuracy of the excision as reflected in the specimen weights. In this study we look at the outcomes of intraoperatively and preoperatively placed guidewires using ultrasound for impalpable breast lesions between 2015 -2018 in the Cambridge Breast Unit. The primary outcomes are re-excision rate and average specimen weights. METHODS: Patients undergoing breast conservation surgery for impalpable lesions from 01/01/2015 to 30/07/2018 were included. Data was collected retrospectively from our electronic records system EPIC and analysed. RESULTS The results were divided into intraoperative localisations and preoperative localisations. A total of 441 lesions in 415 patients were included in this study. Preoperative localisationIntraoperative localisationNumber of patients193222Number of lesions210231*Re-excision rate per patient %19.2%14.0%Specimen weight per patient (grams)39.4g24.2g*Fishers exact 0.24 (NS) CONCLUSION: Impalpable lesions can be successfully localised using ultrasound guidance and a guidewire both intraoperatively and preoperatively with good outcomes. Intraoperative localisation has lower re-excision rates and specimen weights in our study as well as many other benefits for the patient and surgeon. We have looked into how easily and quickly we can train ultrasound naïve trainees in this technique and have achieved good results. Citation Format: Primeera Wignarajah, Vasiliki Papalouka, Parto Forouhi. The use of intraoperative ultrasound and guidewire placement to obtain low re-excision rates and increased accuracy of excision in impalpable breast lesions at the Cambridge Breast Unit [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-20-21.

This Editorial Comment discusses the following AJR article: Human Epidermal Growth Factor Receptor Type 2-Positive Breast Cancer: Association of MRI and Clinicopathologic Features With Tumor-Infilt...

Background: Nonpalpable breast lesions require localization, the gold standard for which is preoperative ultrasound-guided wire localization (PUGWL). Our unit also employs intraoperative ultrasound-guided wire localization (IUGWL). Here we evaluate PUGWL and IUGWL outcomes between 2014 and 2018. Primary outcomes were reoperation rates, complication rates and average specimen weights. Trainee feedback and cost analysis assessed IUGWL viability. Methods: Prospectively recorded data were collected. 511 patients were included (241 PUGWL and 270 IUGWL). Results: Reoperation rates: PUGWL 17.7% versus IUGWL 13.9% (p = 0.28) . Complication rates: PUGWL 5.8% versus IUGWL 6.6% (p = 0.72) . Average specimen weight: PUGWL 34.2 g versus IUGWL 24.3 g (p < 0.0001) . Trainees needed 15 supervised cases to be IUGWL competent. Performing IUGWL saves £289 per localization. Conclusion: IUGWL outcomes are comparable to those of PUGWL. IUGWL is cost-effective, patient-friendly and easy to learn and replicate. IUGWL merits wider dissemination and further planned research.

Hyperpolarized 13C-MRI is an emerging tool for probing tissue metabolism by measuring 13C-label exchange between intravenously injected hyperpolarized [1–13C]pyruvate and endogenous tissue lactate. Here, we demonstrate that hyperpolarized 13C-MRI can be used to detect early response to neoadjuvant therapy in breast cancer. Seven patients underwent multiparametric 1H-MRI and hyperpolarized 13C-MRI before and 7–11 days after commencing treatment. An increase in the lactate-to-pyruvate ratio of approximately 20% identified three patients who, following 5–6 cycles of treatment, showed pathological complete response. This ratio correlated with gene expression of the pyruvate transporter MCT1 and lactate dehydrogenase A (LDHA), the enzyme catalyzing label exchange between pyruvate and lactate. Analysis of approximately 2,000 breast tumors showed that overexpression of LDHA and the hypoxia marker CAIX was associated with reduced relapse-free and overall survival. Hyperpolarized 13C-MRI represents a promising method for monitoring very early treatment response in breast cancer and has demonstrated prognostic potential. Significance: Hyperpolarized carbon-13 MRI allows response assessment in patients with breast cancer after 7–11 days of neoadjuvant chemotherapy and outperformed state-of-the-art and research quantitative proton MRI techniques.

Introduction Women with mammographically dense breasts have an increased risk of breast cancer. Dense breasts can limit detection of small breast lesions due to overlapping fibroglandular tissue. BRAID is a randomised, multi-centre UK study assessing the impact of supplementary imaging, including abbreviated breast MRI (ABB-MRI), in detection of breast cancer in women aged 50-70 years with dense breasts. ABB-MRI is a shorter protocol breast MRI, allowing much faster acquisition times. The aim of this study is to review the feasibility of introducing ABB-MRI into the NHS setting as a part of a research trial. Protocol ABB-MRI is performed on a 1.5 tesla MRI scanner. Sequences obtained include a 2 mm axial T2 weighted sequence, a dual echo (Dixon water/fat separation) 3D DCE acquisition consisting of one pre- and two post-contrast images with generation of post-contrast subtracted images and post-processed MIP images. Scheduling ABB-MRIs are performed on a dedicated breast MRI list. Participants arrive 30 minutes prior to appointment time with pre-filled safety questionnaire. ABB-MRIs are scheduled for a 20-minute appointment slot, allowing 10 women to be scanned in a 3-hour session. Specific roles are allocated to staff members. Improving Efficiency of ABB-MRI in the UK Challenges encountered are similar to those encountered with FDP: IV cannulation, BMI and claustrophobia. Dedicated MR sessions with standard contrast doses and prefilled safety questionnaires help improve efficiency of sessions and allow examination times under 15 minutes.

Muscle Lim Protein (MLP) is a protein with multiple functional roles in striated muscle physiology and pathophysiology. Herein, we demonstrate that MLP directly binds to slow, fast, and cardiac myosin-binding protein C (MyBP-C) during myogenesis, as shown by yeast two-hybrid and a range of protein-protein interaction assays. The minimal interacting domains involve MLP inter-LIM and MyBP-C [C4]. The interaction is sensitive to cytosolic Ca2+ concentrations changes and to MyBP-C phosphorylation by PKA or CaMKII. Confocal microscopy of differentiating myoblasts showed MLP and MyBP-C colocalization during myoblast differentiation. Suppression of the complex formation with recombinant MyBP-C [C4] peptide overexpression, inhibited myoblast differentiation by 65%. Suppression of both MLP and MyBP-C expression in myoblasts by siRNA revealed negative synergistic effects on differentiation. The MLP/MyBP-C complex modulates the actin activated myosin II ATPase activity in vitro, which could interfere with sarcomerogenesis and myofilaments assembly during differentiation. Our data demonstrate a critical role of the MLP/MyBP-C complex during early myoblast differentiation. Its absence in muscles with mutations or aberrant expression of MLP or MyBP-C could be directly implicated in the development of cardiac and skeletal myopathies.

Breast magnetic resonance imaging (MRI) is the technique of choice in detection, local staging, and monitoring of breast cancer; however, breast MRI results in the detection of more indeterminate/suspicious lesions that need to be histopathologically proven to guide patient management than any other breast imaging method. If such abnormalities are not detectable in any of the conventional imaging tools (mammography (MMG) or ultrasound) then an MRI-guided biopsy needs to be performed to obtain a diagnosis. Breast MRI-guided biopsy is a time-consuming and complex procedure that requires specific equipment and experienced, well-trained staff. This review article explores and illustrates the indications, the currently available technologies, and the technique of breast MRI-guided biopsy, and explains the importance of careful imaging review and selection of cases. We correlate the radiological-pathological findings and highlight the impact on patient management in a multidisciplinary setting.

The muscle LIM protein (MLP) and cofilin 2 (CFL2) are important regulators of striated myocyte function. Mutations in the corresponding genes have been directly associated with severe human cardiac and skeletal myopathies, and aberrant expression patterns have often been observed in affected muscles. Herein, we have investigated whether MLP and CFL2 are involved in common molecular mechanisms, which would promote our understanding of disease pathogenesis. We have shown for the first time, using a range of biochemical and immunohistochemical methods, that MLP binds directly to CFL2 in human cardiac and skeletal muscles. The interaction involves the inter-LIM domain, amino acids 94 to 105, of MLP and the amino-terminal domain, amino acids 1 to 105, of CFL2, which includes part of the actin depolymerization domain. The MLP/CFL2 complex is stronger in moderately acidic (pH 6.8) environments and upon CFL2 phosphorylation, while it is independent of Ca(2+) levels. This interaction has direct implications in actin cytoskeleton dynamics in regulating CFL2-dependent F-actin depolymerization, with maximal depolymerization enhancement at an MLP/CFL2 molecular ratio of 2:1. Deregulation of this interaction by intracellular pH variations, CFL2 phosphorylation, MLP or CFL2 gene mutations, or expression changes, as observed in a range of cardiac and skeletal myopathies, could impair F-actin depolymerization, leading to sarcomere dysfunction and disease.

Aims To investigate whether genetic variants of the histidine-rich calcium (HRC)-binding protein are associated with idiopathic dilated cardiomyopathy (DCM) and its progression. Methods and results We screened 123 idiopathic DCM patients and 96 healthy individuals by single-strand conformation polymorphism analysis and direct sequencing for genetic variants in HRC. Six polymorphisms were detected: Leu35Leu (A/G), Ser43Asn (G/A), Ser96Ala (T/G), Glu202_Glu203insGlu (−/GAG), Asp261del (GAT/−), and an in-frame insertion of 51 amino acids at His321. The analysis of their frequencies did not reveal any significant correlation with DCM development. However, the Ser96Ala polymorphism exhibited a statistically significant correlation with the occurrence of life-threatening ventricular arrhythmias. During a follow-up of 4.02 ± 2.4 years, the risk for ventricular arrhythmias was higher (HR, 9.620; 95% CI, 2.183–42.394; P = 0.003) in the Ala/Ala patients, compared with Ser/Ser homozygous patients. On multivariable Cox regression analysis, the Ser96Ala polymorphism was the only significant genetic arrythmogenesis predictor in DCM patients (HR, 4.191; 95% CI, 0.838–20.967; P = 0.018). Conclusion The Ser96Ala genetic variant of HRC is associated with life-threatening ventricular arrhythmias in idiopathic DCM and may serve as an independent predictor of susceptibility to arrhythmogenesis in the setting of DCM.

Intracellular calcium is a major coordinator of numerous aspects of cellular physiology, including muscle contractility and cell survival. In cardiac muscle, aberrant Ca(2+) cycling has been implicated in a range of pathological conditions including cardiomyopathies and heart failure. The sarco(endo)plasmic reticulum Ca(2+) transport adenosine triphosphatase (SERCA2a) and its regulator phospholamban (PLN) have a central role in modulating Ca(2+) homeostasis and, therefore, cardiac function. Herein, we discuss the mechanisms through which SERCA2a and PLN control cardiomyocyte function in health and disease. Emphasis is placed on our newly identified PLN-binding partner HS-1-associated protein X-1 (HAX-1), which has an anti-apoptotic function and presents with numerous similarities to Bcl-2. Recent evidence indicates that proteins of the Bcl-2 family can influence ER Ca(2+) content, a critical determinant of cellular sensitivity to apoptosis. The discovery of the PLN/HAX-1 interaction therefore unveils an important new link between Ca(2+) homeostasis and cell survival, with significant therapeutic potential.

This study assessed the long-term effect of vagotomy on the structure and passive mechanical characteristics of the thoracic aorta under a wide range of stresses in vitro. Eight healthy Landrace pigs underwent bilateral vagotomy distal to the origin of the recurrent laryngeal nerve, and 10 pigs were sham-operated. Three months post-surgery, the aorta was excised and specimens from the ascending aorta, arch, and descending thoracic aorta were subjected to histomorphometrical evaluation and uniaxial tensile-testing until failure. Elastic modulus-stress data were plotted and submitted to regression analysis. Structural remodeling after vagotomy was characterized as vascular growth in the ascending aorta and arch, and as thinning in the descending thoracic aorta. In the aortic segments of vagotomized animals, the area density of elastin and collagen was increased, but smooth muscle density was decreased. Similar differences in regression parameters and failure strength between groups were found in all aortic segments, indicating that the vessel wall was stiffer and stronger in vagotomized animals. In the clinical setting, disease states or drugs blocking the regulatory role of the vagi nerves on the aortic wall may have undesirable consequences on the mechanical performance of the thoracic aorta, and therefore on hemodynamic homeostasis.

Muscle lim protein (MLP) has emerged as a critical regulator of striated muscle physiology and pathophysiology. Mutations in cysteine and glycine-rich protein 3 (CSRP3), the gene encoding MLP, have been directly associated with human cardiomyopathies, whereas aberrant expression patterns are reported in human cardiac and skeletal muscle diseases. Increasing evidence suggests that MLP has an important role in both myogenic differentiation and myocyte cytoarchitecture, although the full spectrum of its intracellular roles has not been delineated. We report the discovery of an alternative splice variant of MLP, designated as MLP-b, showing distinct expression in neuromuscular disease and direct roles in actin dynamics and muscle differentiation. This novel isoform originates by alternative splicing of exons 3 and 4. At the protein level, it contains the N-terminus first half LIM domain of MLP and a unique sequence of 22 amino acids. Physiologically, it is expressed during early differentiation, whereas its overexpression reduces C2C12 differentiation and myotube formation. This may be mediated through its inhibition of MLP/cofilin-2-mediated F-actin dynamics. In differentiated striated muscles, MLP-b localizes to the sarcomeres and binds directly to Z-disc components, including ?-actinin, T-cap and MLP. The findings of the present study unveil a novel player in muscle physiology and pathophysiology that is implicated in myogenesis as a negative regulator of myotube formation, as well as in differentiated striated muscles as a contributor to sarcomeric integrity.

Cardiac contractility is regulated through the activity of various key Ca2+-handling proteins. The sarco(endo)plasmic reticulum (SR) Ca2+transport ATPase (SERCA2a) and its inhibitor phospholamban (PLN) control the uptake of Ca2+by SR membranes during relaxation. Recently, the antiapoptotic HS-1–associated protein X-1 (HAX-1) was identified as a binding partner of PLN, and this interaction was postulated to regulate cell apoptosis. In the current study, we determined that HAX-1 can also bind to SERCA2. Deletion mapping analysis demonstrated that amino acid residues 575–594 of SERCA2's nucleotide binding domain are required for its interaction with the C-terminal domain of HAX-1, containing amino acids 203-245. In transiently cotransfected human embryonic kidney 293 cells, recombinant SERCA2 was specifically targeted to the ER, whereas HAX-1 selectively concentrated at mitochondria. On triple transfections with PLN, however, HAX-1 massively translocated to the ER membranes, where it codistributed with PLN and SERCA2. Overexpression of SERCA2 abrogated the protective effects of HAX-1 on cell survival, after hypoxia/reoxygenation or thapsigargin treatment. Importantly, HAX-1 overexpression was associated with down-regulation of SERCA2 expression levels, resulting in significant reduction of apparent ER Ca2+levels. These findings suggest that HAX-1 may promote cell survival through modulation of SERCA2 protein levels and thus ER Ca2+stores.