Malignant Human Breast Tissues Research Articles

Spatially Segregated Macrophage Populations Predict Distinct Outcomes in Colon Cancer.

Tumor-associated macrophages are transcriptionally heterogeneous, but the spatial distribution and cell interactions that shape macrophage tissue roles remain poorly characterized. Here, we spatially resolve five distinct human macrophage populations in normal and malignant human breast and colon tissue and reveal their cellular associations. This spatial map reveals that distinct macrophage populations reside in spatially segregated micro-environmental niches with conserved cellular compositions that are repeated across healthy and diseased tissue. We show that IL4I1+ macrophages phagocytose dying cells in areas with high cell turnover and predict good outcome in colon cancer. In contrast, SPP1+ macrophages are enriched in hypoxic and necrotic tumor regions and portend worse outcome in colon cancer. A subset of FOLR2+ macrophages is embedded in plasma cell niches. NLRP3+ macrophages co-localize with neutrophils and activate an inflammasome in tumors. Our findings indicate that a limited number of unique human macrophage niches function as fundamental building blocks in tissue. Significance: This work broadens our understanding of the distinct roles different macrophage populations may exert on cancer growth and reveals potential predictive markers and macrophage population-specific therapy targets.

H&E-like histology of unstained fresh and formalin fixed breast tissue with Photo Acoustic Remote Sensing (PARS) microscopy.

e12590 Background: Approximately 30% of breast cancer patients undergoing breast-conserving surgery (BCS) require re-excision(s) to obtain clear margins, causing delays in adjuvant treatment, poor aesthetic results, and increased infection rates, costs, and patient anxiety. Frozen section pathology assessment (FSA) reduces re-excision rates from 27% to 6%, but FSA extends operative times and has a false negative rate of 17%. Photo-Acoustic Remote Sensing (PARS) is a new laser-based light microscope that permits non-contact cellular resolution imaging of unstained tissues. Methods: We used an ultraviolet reflection-mode PARS microscope to study i) formalin-fixed, paraffin embedded (FFPE) breast tissue blocks, ii) unstained thin sections of FFPE invasive ductal carcinoma and ductal carcinoma in situ, iii) formalin fixed bulk surgical specimens of benign and malignant human breast tissue, and iv) benign and malignant fresh rodent mammary tissue without fixation, processing, or staining. Fresh tissues were imaged after a range of warm ischemic times and across a range of cold ischemic times in neutral phosphate buffered saline at 4°C. For each condition, an ultraviolet laser was used to excite DNA and other cellular components in these samples, and signals were captured using a continuous-wave detection laser. The PARS signal was false-colored to closely replicate traditional hematoxylin and eosin staining. Results: In all fixed tissues, PARS virtual histology images were of diagnostic quality, permitted margin assessment, and analogous to transmission light microscopy of standard hematoxylin and eosin-stained FFPE slides, achieved without tissue sectioning or tissue staining. Furthermore, PARS microscopy also provided cellular level virtual histology images in fresh breast tissue with warm and cold ischemic times ranging from twenty minutes to two hours; these images have no available clinical comparators as non-contact cellular level imaging of unprocessed fresh tissue has not previously been reported. In aggregate, we demonstrate the feasibility of PARS to provide diagnostic and margin assessment images across a range of tissues including formalin fixed and freshly resected, unstained, unprocessed breast tissue. Conclusions: PARS is a new microscope technology addressing the practical needs of intraoperative margin assessment during BCS: i) no requirement for tissue staining, ii) rapid acquisition of hematoxylin and eosin-like images without the requirement for tissue freezing, embedding, or sectioning, iii) diagnostic quality cellular resolution, and iv) assessment of resected bulk tissue margins. In principle, this technology may also permit label-free non-contact intraoperative margin assessment of the surgical cavity. These data support the clinical development and evaluation of PARS microscopic intraoperative assessment of BCS margins.

Automated full-field polarization-sensitive optical coherence tomography diagnostic systems for breast cancer.

Intraoperative delineation of breast cancer is a major challenge. An effective breast tissue screening technique may reduce the risk of re-excision during surgery by specifically identifying positive margins. In this study, a high-resolution automated full-field polarization-sensitive optical coherence tomography (FF-PS-OCT) system was developed to classify healthy and malignant human breast tissue from quantitative phase retardation information of the tissues in ex vivo. Twelve breast tissue samples [four healthy, eight malignant (cancerous)] were imaged with the FF-PS-OCT system and the different phase features were extracted from the acquired OCT images (106), based on the differences in the optical signatures of the healthy and malignant tissues. A linear support vector model classifier was trained using 75 images, with a sensitivity of 92.10% and specificity of 89.18% was achieved. Thirty-one images were used to test the model, with a sensitivity of 90.90% and specificity of 85.0% achieved.

SAXS-CT: a nanostructure resolving microscopy for macroscopic biologic specimens

SAXS-CT is an emerging powerful imaging technique which bridges the gap between information retrieved from high-resolution local techniques and information from low-resolution, large field-of-view imaging, to determine the nanostructure characteristics of well-ordered tissues, e.g., mineralized collagen in bone. However, in the case of soft tissues, features such as poor nanostructural organization and high susceptibility to radiation-induced damage limit the use of SAXS-CT. Here, by combining the freeze-drying the specimen, preceded by formalin fixation, with the nanostructure survey we identified and monitored alterations on the hierarchical arrangement of triglycerides and collagen fibrils three-dimensionally in breast tumor specimens without requiring sample staining. A high density of aligned collagen was observed precisely on the invasion front of the breast carcinoma, showing the direction of cancer spread, whereas substantial content of triglycerides was identified, where the healthy tissue was located. Finally, the approach developed here provides a path to high-resolution nanostructural probing with a large field-of-view, which was demonstrated through the visualization of characteristic nanostructural arrangement and quantification of content and degree of organization of collagen fibrils in normal, benign and malignant human breast tissue.

A targeted mass spectrometry immunoassay to quantify osteopontin in fresh-frozen breast tumors and adjacent normal breast tissues

Osteopontin (OPN) is a multifunctional protein that can activate cell-signaling pathways and lead to cancer development and metastasis. Elevated OPN expression was reported in different cancer types, including breast tumors. Here, we present a new immuno-mass spectrometry method for OPN quantification in fresh-frozen malignant and adjacent normal human breast tissues. For quantification we used two proteotypic peptides: OPN-peptide-1 and OPN-peptide-2. Peptide concentrations were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in multiple reaction monitoring (MRM) mode with stable isotope standards (SIS) and immuno-affinity enrichment for isolation of OPN peptides. Based on the OPN-peptide-1, the average OPN concentration in normal breast tissue was 19.42 μg/g, while the corresponding level in breast tumors was 603.9 μg/g. Based on OPN-peptide-2, the average concentration in normal breast tissue was 19.30 μg/g and in breast tumors 535.0 μg/g. In ER/PR/HER2(−) patients the OPN levels in breast tumors were significantly higher than in corresponding normal breast tissue samples, whereas in the single ER/PR/HER2(+) patient the OPN concentration in tumor samples was lower than in normal breast tissue sample. In conclusion, the current method is considered promising for the quantification of OPN in research and in clinical settings and should be further studied in breast cancer patients. SignificanceA new immuno-mass spectrometry method was successfully developed and applied to determine OPN concentrations in malignant tumor and normal breast tissues from six patients, and the method is promising for OPN quantification in both research and clinical settings.

Analysis of PKC-ζ protein levels in normal and malignant breast tissue subtypes.

It is estimated that breast cancer will be the second leading cause of cancer-associated mortality in women in 2018. Previous research has demonstrated that the atypical protein kinase C-ζ (PKC-ζ) is a component of numerous dysregulated pathways in breast cancer, including cellular proliferation, survival, and cell cycle upregulation. The present study investigated the PKC-ζ protein in breast tissue to evaluate its potential as a biomarker for breast cancer invasion, and demonstrated that an overexpression of PKC-ζ protein can be indicative of carcinogenesis. The present study analyzed the expression of PKC-ζ in individuals with no tumor complications and malignant female human breast tissue samples (lobular carcinoma in situ, invasive lobular carcinoma, ductal carcinoma in situ and invasive ductal carcinoma) with the use of western blot analysis, immunohistochemistry and statistical analysis (83 samples). The present study also evaluated the invasive behavior of MDA-MB-231 breast cancer cells following the knockdown of PKC-ζ with a Transwell invasion assay and an immunofluorescent probe for filamentous actin (F-actin) organization. The data demonstrated that PKC-ζ expression was identified to be higher in invading tissues when compared with non-invading tissues. The results also suggest that PKC-ζ is more abundant in ductal tissues when compared with lobular tissues. In addition, the protein studies also suggest that PKC-ζ is a component for invasive behavior through the Ras-related C3 botulinum toxin substrate 1 (Rac1) and Ras homolog gene family member A (RhoA) pathway, and PKC-ζ is required for the F-actin reorganization in invasive cells. Therefore, PKC-ζ should be considered to be a biomarker in the development of breast cancer as well as an indicator of invading tumor cells.

Using Filter Factors for Regularization in Ultrasound Tomography.

The motivation for ultrasound tomography is the location and identification of malignant human breast tissues for the purpose of detecting breast cancer. Although mammography is widely used for breast cancer detection, it has a high false positive rate and does not always accurately separate malignant tissue from benign tissue. Ultrasound tomography is used to compensate for these shortcomings. The computational model for ultrasound tomography is based upon solving an inverse scattering problem by finding the approximate total field and unknown scattering function using an iterative method. The principal computational problem involved is the solution of an ill-conditioned linear system, $Xy\approx b$, arising from an ill-posed problem written as an integral equation. In this paper, we explore the DSVD and the DGSVD regularization methods to solve the inverse scattering problem. The DGSVD algorithm gives better results than the DSVD algorithm when we introduce noise in either one or both sides of the linear system $Xy\approx b$.

Time–frequency based photoacoustic spectral response technique for differentiating human breast masses

Breast cancer is the most prevalent form of cancer among women. Non-invasive and early stage diagnosis of breast cancer would be pragmatic to reduce unnecessary biopsy and mortality rate. We propose Wigner–Ville distribution (WVD) based photoacoustic spectral response (WVD-PASR), a tissue elasticity dependent technique for human breast cancer diagnosis. Since tissue elasticity acts as a finger print of many diseases including cancer, the proposed technique would differentiate normal from malignant breast masses. In addition, WVD is an advanced signal processing tool for time–frequency analysis which provides frequency domain parameters along with time information. This feature of WVD would elicit critical information about frequency component of the PA time domain signal. Since frequency content of PA signal is related to tissue elasticity, WVD-PASR would differentiate human breast masses. Applying the proposed technique on normal and malignant human breast tissues reveals that frequency analysis of malignant tissues contain two dominant peaks as compared to one dominant peak for a normal tissue. Besides having two dominant frequencies, the energy density of malignant breast is significantly more than that of normal tissue. Hence the proposed tool, in addition to detection of malignant breast tumours, could also provide tissue elasticity and other mechano-biological properties.

Prolactin/androgen-inducible carboxypeptidase-D increases with nitrotyrosine and Ki67 for breast cancer progression in vivo, and upregulates progression markers VEGF-C and Runx2 in vitro.

Carboxypeptidase-D (CPD) cleaves C-terminal arginine (Arg) to produce nitric oxide (NO). Upregulation of CPD and NO by 17β-estradiol, prolactin (PRL), and androgen increases survival of human breast cancer (BCa) cells in vitro. To demonstrate similar events in vivo, CPD, nitrotyrosine (NT, hallmark of NO action), androgen receptor (AR), prolactin receptor (PRLR), and phospho-Stat5a (for activated PRLR) levels were evaluated in benign and malignant human breast tissues, and correlated with cell proliferation (Ki67) and BCa progression (Cullin-3) biomarkers. Paraffin-embedded breast tissues were analyzed by immunohistochemistry (IHC). BCa progression markers in human MCF-7 and T47D BCa cell lines treated with NO donor SIN-1 or PRL, ±CPD inhibitors were analyzed by RT-qPCR and immunoblotting. IHC showed progressive increases in CPD, NT, Ki67, and Cullin-3 from low levels in benign tissues to high levels in ductal carcinoma in situ, low-grade, high-grade, and triple-negative BCa. CPD and NT staining were closely associated, implicating CPD in NO production. Phospho-Stat5a increased significantly from benign to high-grade BCa and was mostly nuclear. AR and PRLR were abundant in benign breast and BCa, including triple-negative tumors. SIN-1 and PRL increased VEGF-C and Runx2, but not Cullin-3, in BCa cell lines. PRL induction of VEGF-C and Runx2 was inhibited partly by CPD inhibitors, implicating NO, produced by PRL-regulated CPD, in BCa progression. The CPD-Arg-NO pathway contributes to BCa progression in vitro and in vivo. PRL/androgen activation of the pathway support combined AR and PRLR blockade as an additional therapy for BCa.

Abstract 3934: Analysis of PKC-ζ protein and mRNA levels in normal and malignant breast tissue

Abstract It is estimated that in 2015 breast cancer will be the second leading cause of cancer death in women. For this purpose, biochemical markers for breast cancer have been investigated, to assist in early detection and more accurate diagnoses. In breast cancer tissue, the atypical isozyme of protein kinase C zeta, PKC-ζ, has been a topic in research; It has been shown that an overexpression of this protein may be indicative of developing carcinogenesis and contributes to proliferation through the NF kappa B pathway, which is a stress-regulated switch for cell survival. In this investigation, the expression of PKC-ζ was analyzed in normal and malignant female human breast tissue samples by Western blot, immunoprecipitation and PCR. In the preliminary results, the malignant breast tissue samples illustrated a significant expression of PKC ζ when compared to the expression of PKC-ζ in normal breast tissue samples. The same tissues were also processed for total RNA isolation which was followed by cDNA synthesis and Real Time PCR. The level of PKC-ζ mRNA was tested and no overexpression was observed in either malignant or normal breast tissue samples. While protein studies may suggest that PKC-ζ could be considered a biomarker for breast cancer, the same cannot be said about mRNA levels. The overexpression of PKC-ζ protein level and the normal PKC-ζ mRNA level are indicators of possible miRNA activity that may regulate translation in malignant tissues but not the normal. Citation Format: Christopher Apostolatos, Tracess Smalley, Mildred A. Duncan. Analysis of PKC-ζ protein and mRNA levels in normal and malignant breast tissue. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3934.

Stepwise conceptualization in pigeons.

We explored the relation between concept learning and the number of training exemplars, programmed in a stepwise fashion. Eight pigeons (Columba livia) were trained via differential food reinforcement to peck 1 of 2 simultaneously displayed color images: benign or malignant human breast tissue samples. In each session, only 1 exemplar from each category was trained. If the learning criterion was achieved in 1 session, then those 2 exemplars were discarded and 2 new exemplars were trained in the next session. For the consistent group the reinforced category (benign or malignant stimuli for different birds) was maintained throughout all 24 training pairs, but for the inconsistent group the reinforced category was pseudorandomly changed from pair to pair. Pigeons in the consistent group evidenced striking gains in accuracy during the 1st few trials of training on new pairs (exceeding 90% correct over Pairs 10-12), whereas pigeons in the inconsistent group evidenced reliably weaker gains in initial categorization accuracy (rising above only 70% correct after comparable training). Stepwise training involving as few as a dozen exemplars per category was thus sufficient to support robust concept learning in pigeons.

Quantitative micro-elastography: imaging of tissue elasticity using compression optical coherence elastography.

Probing the mechanical properties of tissue on the microscale could aid in the identification of diseased tissues that are inadequately detected using palpation or current clinical imaging modalities, with potential to guide medical procedures such as the excision of breast tumours. Compression optical coherence elastography (OCE) maps tissue strain with microscale spatial resolution and can delineate microstructural features within breast tissues. However, without a measure of the locally applied stress, strain provides only a qualitative indication of mechanical properties. To overcome this limitation, we present quantitative micro-elastography, which combines compression OCE with a compliant stress sensor to image tissue elasticity. The sensor consists of a layer of translucent silicone with well-characterized stress-strain behaviour. The measured strain in the sensor is used to estimate the two-dimensional stress distribution applied to the sample surface. Elasticity is determined by dividing the stress by the strain in the sample. We show that quantification of elasticity can improve the ability of compression OCE to distinguish between tissues, thereby extending the potential for inter-sample comparison and longitudinal studies of tissue elasticity. We validate the technique using tissue-mimicking phantoms and demonstrate the ability to map elasticity of freshly excised malignant and benign human breast tissues.

Investigation of Optical Coherence Microelastography as a Method to Visualize Cancers in Human Breast Tissue.

An accurate intraoperative identification of malignant tissue is a challenge in the surgical management of breast cancer. Imaging techniques that help address this challenge could contribute to more complete and accurate tumor excision, and thereby help reduce the current high reexcision rates without resorting to the removal of excess healthy tissue. Optical coherence microelastography (OCME) is a three-dimensional, high-resolution imaging technique that is sensitive to microscale variations of the mechanical properties of tissue. As the tumor modifies the mechanical properties of breast tissue, OCME has the potential to identify, on the microscale, involved regions of fresh, unstained tissue. OCME is based on the use of optical coherence tomography (OCT) to measure tissue deformation in response to applied mechanical compression. In this feasibility study on 58 ex vivo samples from patients undergoing mastectomy or wide local excision, we demonstrate the performance of OCME as a means to visualize tissue microarchitecture in benign and malignant human breast tissues. Through a comparison with corresponding histology and OCT images, OCME is shown to enable ready visualization of features such as ducts, lobules, microcysts, blood vessels, and arterioles and to identify invasive tumor through distinctive patterns in OCME images, often with enhanced contrast compared with OCT. These results lay the foundation for future intraoperative studies. Cancer Res; 75(16); 3236-45. ©2015 AACR.

Expression of Glypican-3 (GPC3) in Malignant and Non-malignant Human Breast Tissues

Specific reports have linked GPC3 with cancer. Its usefulness as a marker has been proved for hepatocarcinoma, melanoma and ovary carcinoma. However, there are no studies analyzing GPC3 usefulness as a biomarker in mammary tumors. The aim of this work was to analyze GPC3 expression in breast tissues and to determine whether it might be useful as a biomarker in breast cancer patients. Expression level of GPC3 mRNA in Brazilian and Argentine human breast tumor (n=121) and peritumoral tissue (n=77) samples was analyzed using qRT-PCR. GPC3 protein expression was analyzed from 69 breast cancer and 10 peritumoral samples using IHC. Statistical analyses were done to evaluate the clinical-pathological significance of GPC3 expression. We found that Brazilian and Argentine populations are statistically different regarding GPC3 mRNA expression. In Argentine patients a lower GPC3 mRNA expression was found in tumors as compared to peritumoral tissues. No association was found between GPC3 mRNA and protein expression and the clinical-pathological parameters. The Kaplan-Meier curves suggested that elevated levels of GPC3 mRNA are associated with relapse. Our results indicate differential expression of GPC3 in mammary tumors in comparasion to normal breast tissues. They also suggest the potential role of GPC3 as a biomarker and the importance of deepening the study.

Kinetic characterization of lactate dehydrogenase in normal and malignant human breast tissues.

BackgroundAerobic glycolysis rate is higher in breast cancer tissues than adjacent normal tissues which providethe ATP, lactate and anabolic precursors required for tumourgenesis and metastasis. Lactate dehydrogenase (LDH) is a critical enzyme during aerobic glycolysis as it is typically responsible for the production of lactate and regeneration of NAD+, which allows for the continued functioning of glycolysis even in the absence of oxygen. LDH has been found to be highly expressed in breast tumors. Enzyme kinetic characteristics is related to environmentinvolving the enzyme, and tumor microenvironment has distinct features relative to adjacent normal tissues, thus we hypothesized that LDH should have different kinetic characteristics in breast tumors compared to normal breast tissues.MethodsLDH was partially purifiedfrom human breast tumors and normal tissues, which were obtained directly from operating room. TheMichaelis-Menten constant (Km), maximum velocity (Vmax), activation energy (Ea) and enzyme efficiency in breast tumors and normal tissueswere determined.ResultsIt was found that tumor LDH affinity in forward reaction was the same as normal LDH but Vmax of cancerous LDH was higher relative to normal LDH. In reverse reaction, affinity of tumor LDH for lactate and NAD+ was lower than normal LDH, also enzyme efficiency for lactate and NAD+ was higher in normal samples. The Ea of reverse reaction was higher in cancerous tissues.ConclusionsIt was concluded that thelow LDH affinity for lactate and NAD+ is a valuable tool for preserving lactate by cancer cells. We also conclude that increasing of LDH affinity may be a valid molecular target to abolish lactate dependent tumor growth and kinetic characteristics of LDH could be a novel diagnostic parameter for human breast cancer.

Abstract 2944: Decline in arylsulfatase B (N-acetylgalactosamine-4-sulfatase) leads to increased expression of the transmembrane glycoprotein GPNMB

Abstract The enzyme arylsulfatase B (ARSB; N-acetylgalactosamine-4-sulfatase), which removes 4-sulfate groups from chondroitin-4-sulfate (C4S) and dermatan sulfate, is reduced in malignant human epithelial breast, colonic, and prostate cells and tissues. Lower ARSB immunohistochemical scores have been associated with shorter intervals to recurrence in paired cases of prostate cancer and with propensity for metastasis in malignant colonic cells. The transmembrane glycoprotein GPNMB has been shown to be increased in malignant melanoma, glioblastoma multiforme, and mammary carcinoma, and is a target of antibody therapy in triple-negative breast cancers. In the ARSB-deficient mouse, cDNA microarray of prostate tissue demonstrated 9.53-fold increase in expression of GPNMB, compared to age- and gender- matched C57BL/6J wild-type controls. Measurements by ELISA of GPNMB protein in the ARSB-null mouse liver and prostate tissues showed significant increases, compared to C57BL/6J wild-type controls. In the liver of female ARSB-deficient mice, the gpnmb increased to 47.1 ± 5.7 ng/mg protein from 8.5 ± 1.2 ng/mg protein in the control mouse liver (n=5 in each group), and similar six-fold increases occurred in the male ARSB-null mouse liver. Prostate gpnmb increased more that three-fold, and serum levels in female and male null mice were significantly greater. When ARSB was silenced by siRNA in the normal human prostate stromal cell line (WPMY-1), GPNMB increased from 3.6 ± 0.3 ng/mg protein to 18.3 ± 1.1 ng/mg protein, and in the normal human prostate epithelial cell line (WPE1-NB14) from 4.8 ± 0.4 to 24.7 ± 1.6 ng/mg protein. Similarly in the human hepatic cell line, HepG2, GPNMB increased greater than five-fold. Decline in ARSB leads to increased chondroitin-4-sulfation and reduced galectin-3 binding to C4S, enabling increased nuclear translocation of galectin-3. We have shown that the increase in nuclear galectin-3 following decline in ARSB impacts on transcriptional events mediated by AP-1 in human epithelial cells, including increases in HIF-1α and versican. However, in the prostate stromal and epithelial cell lines, AP-1 inhibitors, including a c-Jun mimetic peptide and an oligonucleotide inhibitor of c-Fos DNA-binding, did not reduce the increase in GPNMB expression that followed ARSB silencing. Although the mechanism for the decline in GPNMB expression is unknown at this time, the findings support a critical role for ARSB in vital cell processes and suggest that ARSB may be useful as a therapeutic target in malignancy. Citation Format: Sumit Bhattacharyya, Leo Feferman, Joanne Kramer Tobacman. Decline in arylsulfatase B (N-acetylgalactosamine-4-sulfatase) leads to increased expression of the transmembrane glycoprotein GPNMB. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2944. doi:10.1158/1538-7445.AM2014-2944

Overcoming limitations in diffusion-weighted MRI of breast by spatio-temporal encoding.

Evaluating the usefulness of diffusion-weighted spatio-temporal encoding (SPEN) methods to provide quantitative apparent diffusion coefficient (ADC)-based characterizations of healthy and malignant human breast tissues, in comparison with results obtained using techniques based on spin-echo echo planar imaging (SE-EPI). Twelve healthy volunteers and six breast cancer patients were scanned at 3T using scanner-supplied diffusion-weighted imaging EPI sequences, as well as two fully refocused SPEN variants programmed in-house. Suitable codes were written to process the data, including calculations of the actual b-values and retrieval of the ADC maps. Systematically better images were afforded by the SPEN scans, with negligible geometrical distortions and markedly weaker ghosting artifacts arising from either fat tissues or from strongly emitting areas such as cysts. SPEN-derived images provided improved characterizations of the fibroglandular tissues and of the lesions' contours. When translated into the calculation of the ADC maps, there were no significant differences between the mean ADCs derived from SPEN and SE-EPI: if reliable images were available, both techniques showed that ADCs decreased by nearly two-fold in the malignant lesion areas. SPEN-based sequences yielded diffusion-weighted breast images with minimal artifacts and distortions, enabling the calculation of improved ADC maps and the identification of decreased ADCs in malignant regions.

Dynamic properties of water in breast pathology depend on the histological compounds: distinguishing tissue malignancy by water diffusion coefficients.

BackgroundThe parameters that characterize the intricate water diffusion in tumors may also reveal their distinct pathology. Specifically, characterization of breast cancer could be aided by diffusion magnetic resonance.The present in vitro study aimed to discover connections between the NMR biexponential diffusion parameters [fast diffusion phase (DFDP ), slow diffusion phase (DSDP ), and spin population of fast diffusion phase (P1)] and the histological constituents of nonmalignant (control) and malignant human breast tissue. It also investigates whether the diffusion coefficients indicate tissue status.MethodsPost-surgical specimens of control (mastopathy and peritumoral tissues) and malignant human breast tissue were placed in an NMR spectrometer and diffusion sequences were applied. The resulting decay curves were analyzed by a biexponential model, and slow and fast diffusion parameters as well as percentage signal were identified. The same samples were also histologically examined and their percentage composition of several tissue constituents were measured: parenchyma (P), stroma (St), adipose tissue (AT), vessels (V) , pericellular edema (PCE), and perivascular edema (PVE). Correlations between the biexponential model parameters and tissue types were evaluated for different specimens. The effects of tissue composition on the biexponential model parameters, and the effects of histological and model parameters on cancer probability, were determined by non-linear regression.ResultsMeaningful relationships were found among the in vitro data. The dynamic parameters of water in breast tissue are stipulated by the histological constituents of the tissues (P, St, AT, PCE, and V). High coefficients of determination (R2) were obtained in the non-linear regression analysis: DFDP (R2 = 0.92), DSDP (R2 = 0.81), and P1(R2 = 0.93).In the cancer probability analysis, the informative value (R2) of the obtained equations of cancer probability in distinguishing tissue malignancy depended on the parameters input to the model. In order of increasing value, these equations were: cancer probability (P, St, AT, PCE, V) (R2 = 0.66), cancer probability (DFDP, DSDP)(R2 = 0.69), cancer probability (DFDP, DSDP, P1) (R2 = 0.85).ConclusionHistological tissue components are related to the diffusion biexponential model parameters. From these parameters, the relative probability of cancer in a given specimen can be determined with some certainty.

Inverse Regulation of EGFR/HER1 and HER2-4 in Normal and Malignant Human Breast Tissue

Cross-talk between the estrogen and the EGFR/HER signalling pathways has been suggested as a potential cause of resistance to endocrine therapy in breast cancer. Here, we determined HER1-4 receptor and neuregulin-1 (NRG1) ligand mRNA expression levels in breast cancers and corresponding normal breast tissue from patients previously characterized for plasma and tissue estrogen levels. In tumours from postmenopausal women harbouring normal HER2 gene copy numbers, we found HER2 and HER4, but HER3 levels in particular, to be elevated (2.48, 1.30 and 22.27 –fold respectively; P<0.01 for each) compared to normal tissue. Interestingly, HER3 as well as HER4 were higher among ER+ as compared to ER- tumours (P=0.004 and P=0.024, respectively). HER2 and HER3 expression levels correlated positively with ER mRNA (ESR1) expression levels (r=0.525, P=0.044; r=0.707, P=0.003, respectively). In contrast, EGFR/HER1 was downregulated in tumour compared to normal tissue (0.13-fold, P<0.001). In addition, EGFR/HER1 correlated negatively to intra-tumour (r=-0.633, P=0.001) as well as normal tissue (r=-0.556, P=0.006) and plasma estradiol levels (r=-0.625, P=0.002), suggesting an inverse regulation between estradiol and EGFR/HER1 levels. In ER+ tumours from postmenopausal women, NRG1 levels correlated positively with EGFR/HER1 (r=0.606, P=0.002) and negatively to ESR1 (r=-0.769, P=0.003) and E2 levels (r=-0.542, P=0.020). Our results indicate influence of estradiol on the expression of multiple components of the HER system in tumours not amplified for HER2, adding further support to the hypothesis that cross-talk between these systems may be of importance to breast cancer growth in vivo.

Raman spectra exploring breast tissues: Comparison of principal component analysis and support vector machine‐recursive feature elimination

Raman spectroscopy was explored to diagnose normal, benign, and malignant human breast tissues based on principal component analysis (PCA) and support vector machine-recursive feature elimination (SVM-RFE), and SVM-RFE results were compared with PCA. 1800 Raman spectra were acquired from fresh samples of human breast tissues (normal, fibroadenoma, adenosis, galactoma, and invasive ductal carcinoma) from 168 patients. After set up the SVM-RFE and PCA models, Mahalanobis distance, spectral residuals, sensitivity, specificity, and Matthews correlation coefficient (MCC) were used as the discriminating criteria for evaluating these two methods. The comparison shows that SVM-RFE based on the selection of characteristic peaks better reflects the nature of biopsy and it produces better discrimination, sensitivity, specificity, and MCC for normal (1, 1, 1), malignant (0.93, 0.97, 0.91), and benign (0.95, 0.97, 0.91) breast tissues. The Raman spectroscopy combined with SVM-RFE opens great future in the clinical applications of mammary disease diagnosis.