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Objectives: To suggest an optimal energy level of virtual monochromatic images (VMIs) in dual-energy CT (DECT) arthrography of the wrist., Methods: This retrospective study included 53 patients with wrist CT arthrography. Conventional polychromatic images and VMIs at 4 energy levels (40-70 keV at 10 keV intervals) were obtained. Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured, and qualitative analysis of image quality and diagnostic confidence was performed. For each patient, an energy level with the best image quality was chosen by consensus. Comparisons of quantitative and qualitative parameters between VMI sets were performed., Results: The image noise of bone and muscle were increased with decreasing energy level (P < .001). The noise of contrast was highest on 60 keV VMI. SNR and CNR (between contrast and muscle) were increased with decreasing energy level and were markedly increased between 60 and 50 keV (P < .001). The 60 keV VMI demonstrated the highest image quality and diagnostic confidence, chosen as the best diagnostic image (n = 31/53). Given that the attenuation of the contrast material was low on the conventional image, the optimal energy level of the best VMI tended to be low., Conclusions: Wrist DECT arthrography with VMIs at 60 keV or less could improve image quality and diagnostic performance by increasing SNR and CNR in cases with low contrast attenuation., Advances in Knowledge: Wrist DECT arthrography with VMIs at variable keV could be utilized to enhance SNR and CNR, thereby achieving diagnostic images of high quality., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Purpose: This study aims to delineate the three-dimensional (3D) SPACE MRI findings of the transverse ligament (TL) in whiplash-associated disorder (WAD) patients, and to compare them with those from a nontraumatic group., Methods: A retrospective analysis was performed on cervical spine MRI scans obtained from 46 patients with WAD and 62 nontraumatic individuals. Clinical features, including the WAD grade and stage, were recorded. The TL's morphological grade and the symmetricity of the lateral atlantodental interval was assessed using axial 3D T2-SPACE images. The morphological grading was evaluated using a four-point scale: 0 = homogeneously low signal intensity with normal thickness, 1 = high signal intensity with normal thickness, 2 = reduced thickness, 3 = full-thickness rupture or indistinguishable from surrounding structures. Additionally, the number of cervical levels exhibiting degeneration was documented., Results: When comparing the WAD and nontraumatic groups, a significant difference was observed in the proportion of high-grade TL changes (grade 2 or 3) and the number of degenerated cervical levels. Logistic regression analysis revealed that high-grade TL changes and a lower number of degenerative levels independently predicted the presence of WAD. Within the WAD group, the subset of patients with high-grade TL changes demonstrated a significantly higher mean age than the low-grade group (grade 0 or 1)., Conclusion: High-grade morphological changes in the TL can be detected in patients with WAD through the use of 3D SPACE sequences. Clinical relevance statement 3D SPACE MRI could serve as an instrumental tool in the assessment of TL among patients with WAD. Integrating MRI findings with patient history and symptomology could facilitate the identification of potential ligament damage, and may help treatment and follow-up planning., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study aimed to evaluate the distribution and severity of cartilage damage using magnetic resonance imaging in patients with scaphoid nonunion without advanced wrist arthritis. We retrospectively analysed MRI of patients who underwent osteosynthesis for scaphoid nonunion. Cartilage damage was assessed in eight wrist regions using a modified Whole-Organ Magnetic Resonance Imaging Score. The frequencies of regions affected by any cartilage damage (Score ≥2.5) depicted on MRI were analysed. The study included 32 patients (31 men and one woman), with a mean age of 32 years (SD 11). The distal radioscaphoid (29/32), scaphotrapeziotrapezoid (STT) (22/32), proximal radioscaphoid (14/32) and scaphocapitate (11/32) joints were most commonly affected by degenerative cartilage damage. The STT and proximal radioscaphoid joint were especially likely to be involved in early-stage scaphoid nonunion advanced collapse. We recommend that surgeons should investigate the cartilage status of these joints during decision-making for scaphoid nonunion surgery. Level of evidence: III., Competing Interests: Declaration of conflicting interestsThe authors declare no potential conflicts of interest with respect to the research, authorship, or publication of this article.

Objectives: To demonstrate the magnetic resonance imaging (MRI) findings of interconnections between flexor hallucis longus (FHL) and flexor digitorum longus (FDL) around the Master knot of Henry (MKH)., Methods: Fifty-two MRI scans of adult patients were retrospectively analyzed. The types and subtypes of interconnections between the FHL and FDL were evaluated using the classification suggested by Beger et al based on the direction and number of the tendon slips and contributions to the lesser toes. The layering organization formed by the FDL, quadratus plantae, and tendon slip from the FHL was evaluated. The distance between bony landmarks and the branching site of tendon slips and the cross-sectional area (CSA) of the tendon slips were measured. Descriptive statistics were reported., Results: MRI scans revealed that type 1 interconnection was the most common (81%), followed by type 5 (10%) and types 2 and 4 (4% each). All tendon slips from the FHL contributed to the second toe, and 51% of the tendon slips contributed to the second and third toes. For the layering organization, the two-layered type was the most common (59%), followed by the three-layered (35%) and single-layered (6%) types. The mean distance between the branching site and bony landmarks was longer in the FDL to FHL cases than that in the FHL to FDL cases. The mean CSA of the tendon slips from the FHL to FDL was larger than that of the FDL to FHL., Conclusions: MRI could provide detailed information about the anatomical variations around the MKH., Clinical Relevance Statement: In lower extremity reconstruction surgery, the flexor hallucis longus and flexor digitorum longus tendons serve as donor tendons. A preoperative MRI scan could provide information on anatomical variations around the Master knot of Henry, which can help predict postoperative functional outcomes., Key Points: • Normal anatomical variations around the Master knot of Henry were not extensively studied in the radiology literature before. • MRI identified the various types, sizes, and locations of interconnections between the flexor digitorum longus tendon and the flexor hallucis longus tendon. • MRI is a useful noninvasive tool for evaluating the interconnections between the flexor digitorum longus tendon and the flexor hallucis longus tendon., (© 2023. The Author(s), under exclusive licence to European Society of Radiology.)

Background: Heterogeneous nuclear ribonucleoprotein K (HNRNPK) regulates pre-mRNA processing and long non-coding RNA localization in the nucleus. It was previously shown that shuttling of HNRNPK to the cytoplasm promotes cell proliferation and cancer metastasis. However, the mechanism of HNRNPK cytoplasmic localization, its cytoplasmic RNA ligands, and impact on post-transcriptional gene regulation remain uncharacterized., Results: Here we show that the intermediate filament protein Keratin 19 (K19) directly interacts with HNRNPK and sequesters it in the cytoplasm. Correspondingly, in K19 knockout breast cancer cells, HNRNPK does not localize in the cytoplasm, resulting in reduced cell proliferation. We comprehensively mapped HNRNPK binding sites on mRNAs and showed that, in the cytoplasm, K19-mediated HNRNPK-retention increases the abundance of target mRNAs bound to the 3' untranslated region (3'UTR) at the expected cytidine-rich (C-rich) sequence elements. Furthermore, these mRNAs protected by HNRNPK in the cytoplasm are typically involved in cancer progression and include the p53 signaling pathway that is dysregulated upon HNRNPK knockdown (HNRNPK KD) or K19 knockout (KRT19 KO)., Conclusions: This study identifies how a cytoskeletal protein can directly regulate gene expression by controlling the subcellular localization of RNA-binding proteins to support pathways involved in cancer progression., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Purpose: To evaluate the MRI findings of the craniocervical junction ligaments and compare the 2D TSE sequence and 3D SPACE sequence on cervical spine MRI., Methods: Eighty cervical spine MRIs were retrospectively analyzed, including 2D TSE and 3D SPACE sequences. The visibility and morphology of the transverse ligament (TL) and alar ligament (AL) were evaluated by two readers using a five-point grading scale for visibility (1 = not visible, 2 = barely visible, 3 = adequately visible, 4 = good visibility, 5 = excellent visibility) and a four-point grading scale for morphology (0 = homogeneous low SI with normal thickness, 1 = high SI with normal thickness, 2 = reduced thickness, 3 = full-thickness rupture or indistinguishable from surrounding structures). The grades of the two sequences were compared. Reader agreements were measured using the percentage of exact agreement., Result: The visibility grade of TL was significantly higher in 3D, indicating better visualization. The morphology grade of TL was significantly lower in the 3D, indicating more normal-appearing ligament. The exact agreements of visibility and morphology grade of TL tended to be higher in 3D. On the other hand, there was no significant difference in visibility grade of AL between the two sequences. The morphological grade of AL was significantly higher in 3D. The agreement of the morphological grade of AL tended to be lower in 3D., Conclusion: The utilization of 3D sequences significantly improves the visibility of TL and could potentially reduce false-positive diagnoses of ligament injury., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Digital holographic microscopy is an imaging technique particularly well suited to the study of living cells in culture, as no labeling is required and computed phase maps produce high contrast, quantitative pixel information. A full experiment involves instrument calibration, cell culture quality checks, selection and setup of imaging chambers, a sampling plan, image acquisition, phase and amplitude map reconstruction, and parameter map post-processing to extract information about cell morphology and/or motility. Each step is described below, focusing on results from imaging four human cell lines. Several post-processing approaches are detailed, with an aim of tracking individual cells and dynamics of cell populations., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Objective: To evaluate the usefulness of the longitudinal extent (LE) of high ulnar nerve signal intensity (SI) for the diagnosis of ulnar neuropathy at the elbow (UNE)., Materials and Methods: This retrospective study included 68 patients who underwent elbow MRI. Twenty-seven and 41 patients were enrolled in the UNE and control groups, respectively. Qualitative and quantitative analyses of the SI and size of the ulnar nerve at the cubital tunnel, proximal, and distal to the cubital tunnel were performed. Cross-sectional area (CSA) and nerve-to-muscle contrast ratio (NMCR) were measured at each level. The LE of the hyperintense ulnar nerve was evaluated using axial and coronal images. The presence of space-occupying lesions (SOLs), subluxation, and muscle denervation were recorded. Univariate and multivariate analyses were performed to identify independent predictive factors., Results: Ulnar nerve hyperintensity at and distal to the cubital tunnel, presence of compression, SOL, muscle denervation, LE of hyperintense ulnar nerve, NMCR, and CSA at and distal to the cubital tunnel significantly differed between the two groups. Multivariate logistic regression analysis showed that the LE of the hyperintense ulnar nerve and CSA at the cubital tunnel were independent predictive factors for UNE (p < 0.05)., Conclusion: LE of the hyperintense ulnar nerve could be a useful predictive factor for UNE., (© 2022. ISS.)

A cytoskeletal protein keratin 19 (K19) is highly expressed in breast cancer but its effects on breast cancer cell mechanics are unclear. In MCF7 cells where K19 expression is ablated, we found that K19 is required to maintain rounded epithelial-like shape and tight cell-cell adhesion. A loss of K19 also lowered cell surface E-cadherin levels. Inhibiting internalization restored cell-cell adhesion of  KRT19  knockout cells, suggesting that E-cadherin internalization contributed to defective adhesion. Ultimately, while K19 inhibited cell migration and invasion, it was required for cells to form colonies in suspension. Our results suggest that K19 stabilizes E-cadherin complexes at the cell membrane to maintain cell-cell adhesion which inhibits cell invasiveness but provides growth and survival advantages for circulating tumor cells.

Cyclin D3 regulates the G1/S transition and is frequently overexpressed in several cancer types including breast cancer, where it promotes tumor progression. Here we show that a cytoskeletal protein keratin 19 (K19) physically interacts with a serine/threonine kinase GSK3β and prevents GSK3β-dependent degradation of cyclin D3. The absence of K19 allowed active GSK3β to accumulate in the nucleus and degrade cyclin D3. Specifically, the head (H) domain of K19 was required to sustain inhibitory phosphorylation of GSK3β Ser9, prevent nuclear accumulation of GSK3β, and maintain cyclin D3 levels and cell proliferation. K19 was found to interact with GSK3β and K19-GSK3β interaction was mapped out to require Ser10 and Ser35 residues on the H domain of K19. Unlike wildtype K19, S10A and S35A mutants failed to maintain total and nuclear cyclin D3 levels and induce cell proliferation. Finally, we show that the K19-GSK3β-cyclin D3 pathway affected sensitivity of cells toward inhibitors to cyclin-dependent kinase 4 and 6 (CDK4/6). Overall, these findings establish a role for K19 in the regulation of GSK3β-cyclin D3 pathway and demonstrate a potential strategy for overcoming resistance to CDK4/6 inhibitors.

Objectives: To demonstrate the magnetic resonance imaging (MRI) features of amputation neuromas in lower extremity amputees and investigate independent predictive MRI features for symptomatic neuromas., Methods: This retrospective study included 45 amputation neuromas in 44 lower extremity amputees. Two radiologists assessed the imaging features, including shape, size, type (end-bulb or spindle), signal intensity (SI), heterogeneity, margins, enlarged fascicles, dark outer rim, tail sign, target sign, enhancement, perilesional fibrosis, and muscle denervation. The neuromas were categorized into symptomatic (n = 24) or asymptomatic (n = 21). Symptomatic neuromas were determined based on neuropathic pain characteristics, the presence of Tinel's sign or tenderness, and response to local anesthetic injection. Univariate and multivariate analyses were performed to identify independent predictive MRI features., Results: Of 45 neuromas, 80% (36/45) were end-bulb neuromas and 20% (9/45) were spindle-type neuromas. Eighty percent of the neuromas (36/45) were heterogeneous on T2-weighted images (WIs). Enlarged fascicles were present in 42% (19/45) and dark outer rims in 27% (12/45) of the neuromas. Among the 23 neuromas with enhanced images, 78% (18/23) showed enhancement. Heterogeneity on T2-WIs and enhancement ratios were significantly different between the asymptomatic and symptomatic neuroma groups (p < 0.05). The multivariate analyses indicated that heterogeneity on T2-WIs was an independent factor associated with symptomatic neuromas (p < 0.001)., Conclusions: Heterogeneity on T2-WIs could be a predictive indicator for symptomatic neuromas in lower extremity amputees., Key Points: • Amputation neuromas are classified as either end-bulb or spindle-type. They can show enlarged fascicles, dark outer rims, and enhancement. • Heterogeneity on T2-weighted images could be a predictive indicator for symptomatic neuromas. • Predicting the symptomatic neuroma on MRI would help in effective management of stump pain., (© 2021. European Society of Radiology.)

Purpose: To compare the image quality of brain computed tomography (CT) images reconstructed with deep learning-based image reconstruction (DLIR) and adaptive statistical iterative reconstruction-Veo (ASIR-V)., Methods: Sixty-two patients underwent routine noncontrast brain CT scans and datasets were reconstructed with 30% ASIR-V and DLIR with three selectable reconstruction strength levels (low, medium, high). Objective parameters including CT attenuation, noise, noise reduction rate, artifact index of the posterior cranial fossa, and contrast-to-noise ratio (CNR) were measured at the levels of the centrum semiovale and basal ganglia. Subjective parameters including gray matter-white matter differentiation, sharpness, and overall diagnostic quality were also assessed and compared with the interobserver agreement., Results: There was a gradual reduction in the image noise and artifact index of the posterior cranial fossa as the strength levels of DLIR increased (all P < 0.001) compared with that of ASIR-V. CNR in both the centrum semiovale and basal ganglia levels also improved from the low to high strength levels of DLIR compared with that of ASIR-V (all P < 0.001). DLIR images with medium and high strength levels demonstrated the best subjective image quality scores among the reconstruction datasets. There was moderate to good interobserver agreement for the subjective image quality assessments with ASIR-V and DLIR., Conclusion: On routine brain CT scans, optimized protocols with DLIR allowed significant reduction of noise and artifacts with improved subjective image quality compared with ASIR-V.

Dermoid cysts are lined by keratinizing squamous epithelium and consist of skin appendages such as hair follicles, apocrine glands, and sebaceous glands. They are usually diagnosed during infancy or early childhood, commonly reported in the head and neck region. A dermoid cyst on the back is extremely rare, with only three cases in the pediatric and adult populations. We report a rare case of a dermoid cyst in the subcutaneous layer of the back in an adult. A 75-year-old man presented with a soft, painless mass on his left upper back. Computed tomography revealed a low-density mass nearly identical to the subcutaneous fat in the subcutaneous layer with nodular soft-tissue density components. It was a heterogeneously hyperechoic mass without internal vascularity on ultrasonography. On magnetic resonance imaging, the lesion showed nearly identical signal intensity (SI) to subcutaneous fat on T1 and T2-weighted images. The soft tissue component was intermediately hyperintense on T1- and T2- weighted images with enhancement. This lesion was pre-operatively suspected as a lipoma variant or a well-differentiated liposarcoma/atypical lipomatous tumor because of the fat density or SI and enhancing portion. We demonstrated and reviewed the multimodality imaging features of dermoid cysts at an unusual location and suggested imaging features that could help readers differentiate dermoid cysts from lipomatous tumors. When a mass shows fat density or SI with or without enhancing soft tissue components at the trunk or extremity, dermoid cysts as well as lipomatous tumors could be considered in the differential diagnosis., (© 2021 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

The 8th edition of the American Joint Committee on Cancer (AJCC) TNM staging system subdivides prostatic pT3 tumors into pT3a, which includes cases with extraprostatic extension (EPE) and pT3b, which is defined by the presence of seminal vesicle invasion (SVI) with or without EPE. Yet, it is not established whether combined SVI and EPE impart a worse prognosis compared to SVI alone. We studied a cohort of 69 prostatectomy patients with SVI with or without EPE. Patient age at the time of radical prostatectomy was documented and Gleason score and presence or absence of EPE and/or SVI were determined. Biochemical recurrence (BCR) was defined as a PSA rise >0.2 ng/mL. The frequency of BCR was 33.9% in cases with combined EPE and SVI versus 12.5% in cases with SVI alone (relative risk = 2.71). An additional cohort of 88 patients also showed a higher frequency of lymph node metastasis of 29% in patients with combined SVI and EPE at the time of radical prostatectomy versus a 10% frequency of lymph node metastasis in patients with SVI alone (relative risk = 2.9). Based on our data, we propose further subdividing pT3 prostate cancers into three groups: EPE alone (pT3a), SVI alone (pT3b), and combined EPE and SVI (pT3c). This classification system would more accurately identify patients with pT3 prostate cancer who are more likely to experience worse outcomes and provide clinicians with additional information to aid in follow-up and postoperative treatment decisions., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Cancer cells gain motility through events that accompany modulation of cell shape and include altered expression of keratins. However, the role of keratins in change of cancer cell architecture is not well understood. Therefore, we ablated the expression of keratin 19 (K19) in breast cancer cells of the MDA-MB-231 cell line and found that cells lacking K19 become more elongated in culture, with morphological reversion toward the parental phenotype upon transduction of KRT19. Also, the number of actin stress fibers and focal adhesions were significantly reduced in KRT19 knockout (KO) cells. The altered morphology of KRT19 KO cells was then characterized quantitatively using digital holographic microscopy (DHM), which not only confirmed the phenotypic change of KRT19 KO cells but also identified that the K19-dependent morphological change is dependent on the substrate type. A new quantitative method of single cell analysis from DHM, via average phase difference maps, facilitated evaluation of K19-substrate interactive effects on cell morphology. When plated on collagen substrate, KRT19 KO cells were less elongated and resembled parental cells. Assessing single cell motility further showed that while KRT19 KO cells moved faster than parental cells on a rigid surface, this increase in motility became abrogated when cells were plated on collagen. Overall, our study suggests that K19 inhibits cell motility by regulating cell shape in a substrate-dependent manner. Thus, this study provides a potential basis for the altered expression of keratins associated with change in cell shape and motility of cancer cells. © 2020 International Society for Advancement of Cytometry., (© 2020 International Society for Advancement of Cytometry.)

Introduction: Periostitis in systemic vasculitis is very rare with only a few previously reported cases. The reported cases were seen in polyarteritis nodosa or Takayasu arteritis. We report the first case of periostitis associated with IgA vasculitis with demonstration of computed tomography (CT), magnetic resonance imaging (MRI) features, and serial changes of radiographs., Patient Concerns: A 74-year-old man visited an orthopedic outpatient clinic for pain in both lower legs and left ankle pain. He underwent a total ankle arthroplasty of the left ankle 3 years ago. His medical history disclosed IgA vasculitis/nephropathy caused by cephalosporin antibiotic class 5 months earlier. Plain radiography, MRI of the right lower leg, CT scan of the left ankle showed single lamellar to spiculated periosteal reactions at both tibia, fibula and left calcaneus. There was no evidence of bone or soft tissue mass lesions or cortical destruction., Diagnosis: We concluded that this was a case of periosteal reactions associated with IgA vasculitis for the following reasons: (1) periosteal biopsy was negative for tumor. (2) there was no pulmonary lesion on chest radiography and CT, no history of trauma, inflammatory arthritis, metabolic disease, or genetic disease that could cause periostitis at multiple bones, (3) the initial MRI showed predominant signal changes around the tibial and fibular shafts, possibly explaining subsequent periosteal reactions, and (4) symptoms subsided with conservative treatment and follow-up radiographs showed remodeling of periosteal reactions., Interventions: The patient took conservative management., Outcomes: His calf pain improved, and a radiograph 7 months later showed remodeling to the solid or single lamellar periosteal reaction along the both tibia and left fibula., Conclusion: Awareness of this uncommon manifestation would help differential diagnosis of periostitis and could help decrease the patient's anxiety. It should also be noted that periosteal reactions by benign entities could cause aggressive-looking periosteal reactions in post-operative regions.

Motility is a key property of a cell, required for several physiological processes, including embryonic development, axon guidance, tissue regeneration, gastrulation, immune response, and cancer metastasis. Therefore, the ability to examine cell motility, especially at a single cell level, is important for understanding various biological processes. Several different assays are currently available to examine cell motility. However, studying cell motility at a single cell level can be costly and/or challenging. Here, we describe a method of tracking random cell motility on different substrates such as glass, tissue-culture polystyrene, and type I collagen hydrogels, which can be modified to generate different collagen network microstructures. In this study we tracked MDA-MB-231 breast cancer cells using The CytoSMART TM System (Lonza Group, Basel, Switzerland) for live cell imaging and assessed the average cell migration speed using ImageJ and wrMTrck plugin. Our cost-effective and easy-to-use method allows studying cell motility at a single cell level on different substrates with varying degrees of stiffness and varied compositions. This procedure can be successfully performed in a highly accessible manner with a simple setup.

OBJECTIVE. The objective of our study was to evaluate the relationship between stiff shoulder in patients with a full-thickness rotator cuff tear and MRI findings, especially joint capsule abnormality. MATERIALS AND METHODS. This study included 106 patients with small to large (≤ 5 cm) full-thickness rotator cuff tears. Joint capsule edema and thickness in the axillary recess, obliteration of the subcoracoid fat triangle, fatty degeneration of the torn rotator cuff muscle, and degree of retraction were assessed by two radiologists. The size and location of tears were determined by MRI findings and operative report. Associations between MRI findings and preoperative passive range of motion (ROM) were assessed by simple and multiple linear regression analyses and proportional odds logistic regression analysis. RESULTS. There was a significant, negative linear correlation between limited ROM at forward elevation and thickness of the joint capsule in the glenoid portion of the axillary recess ( p = 0.018), external rotation and joint capsule edema in the humeral portion of the axillary recess ( p = 0.011), and internal rotation and joint capsule edema in the glenoid portion of the axillary recess ( p = 0.007). Male sex ( p = 0.041) and posterosuperior rotator cuff tear ( p = 0.030) were independent predictors of shoulder ROM on external rotation. Degree of fatty degeneration ( p = 0.003) was another independent predictor of shoulder ROM on internal rotation. CONCLUSION. MRI findings-especially joint capsule edema and thickness at the axillary recess-can be useful in predicting shoulder stiffness in patients with rotator cuff tear.

Significance: We introduce an application of machine learning trained on optical phase features of epithelial and mesenchymal cells to grade cancer cells' morphologies, relevant to evaluation of cancer phenotype in screening assays and clinical biopsies., Aim: Our objective was to determine quantitative epithelial and mesenchymal qualities of breast cancer cells through an unbiased, generalizable, and linear score covering the range of observed morphologies., Approach: Digital holographic microscopy was used to generate phase height maps of noncancerous epithelial (Gie-No3B11) and fibroblast (human gingival) cell lines, as well as MDA-MB-231 and MCF-7 breast cancer cell lines. Several machine learning algorithms were evaluated as binary classifiers of the noncancerous cells that graded the cancer cells by transfer learning., Results: Epithelial and mesenchymal cells were classified with 96% to 100% accuracy. Breast cancer cells had scores in between the noncancer scores, indicating both epithelial and mesenchymal morphological qualities. The MCF-7 cells skewed toward epithelial scores, while MDA-MB-231 cells skewed toward mesenchymal scores. Linear support vector machines (SVMs) produced the most distinct score distributions for each cell line., Conclusions: The proposed epithelial-mesenchymal score, derived from linear SVM learning, is a sensitive and quantitative approach for detecting epithelial and mesenchymal characteristics of unknown cells based on well-characterized cell lines. We establish a framework for rapid and accurate morphological evaluation of single cells and subtle phenotypic shifts in imaged cell populations.

Keratin 19 (K19) belongs to the keratin family of proteins, which maintains structural integrity of epithelia. In cancer, K19 is highly expressed in several types where it serves as a diagnostic marker. Despite the positive correlation between higher expression of K19 in tumor and worse patient survival, the role of K19 in breast cancer remains unclear. Therefore, we ablated K19 expression in MCF7 breast cancer cells and found that K19 was required for cell proliferation. Transcriptome analyses of KRT19 knockout cells identified defects in cell cycle progression and levels of target genes of E2F1, a key transcriptional factor for the transition into S phase. Furthermore, proper levels of cyclin dependent kinases (CDKs) and cyclins, including D-type cyclins critical for E2F1 activation, were dependent on K19 expression, and K19-cyclin D co-expression was observed in human breast cancer tissues. Importantly, K19 interacts with cyclin D3, and a loss of K19 resulted in decreased protein stability of cyclin D3 and sensitivity of cells towards CDK inhibitor-induced cell death. Overall, these findings reveal a novel function of K19 in the regulation of cell cycle program and suggest that K19 may be used to predict the efficacy of CDK inhibitors for treatments of breast cancer.

Many issues, such as, DO accumulation, N 2 fixation obstacle, and carbon dioxide diffusion, hamper the application of microalgae-alginate immobilization in wastewater treatment. The objective of this study was to evaluate the effect of the microalgae Nannochloropsis oculata immobilized with the bacterium Bacillus polymyxa in alginate on ammonium and phosphate removal from synthetic wastewater. Results show that the co-immobilized Bacillus-Nannochloropsis can exploit ammonium and phosphate from wastewater more effectively than the immobilized Nannochloropsis , and immobilized Bacillus alone. A significantly higher ammonium and phosphate removal efficiency was found in co-immobilized Bacillus-Nannochloropsis (59.85%, 90.44%) than of that in immobilized Nannochloropsis (49.56%, 77.36%), and Bacillus immobilized (31.46%, 29.66%) alone. Additionally, the most effective co-immobilization mixture ratio for wastewater treatment was found to contain equal suspension (10 8 cell/ml) volume of the Nannochloropsis and Bacillus . Nannochloris and Bacillus can coexist harmoniously with the symbiotic and synergistic relationship, and the Nannochloropsis oculata - Bacillus polymyxa combination can be useful as a potential method to develop novel wastewater treatment.

Robust and reproducible profiling of cell lines is essential for phenotypic screening assays. The goals of this study were to determine robust and reproducible optical phase signatures of cell lines for classification with machine learning and to correlate optical phase parameters to motile behavior. Digital holographic microscopy (DHM) reconstructed phase maps of cells from two pairs of cancer and non-cancer cell lines. Seventeen image parameters were extracted from each cell's phase map, used for linear support vector machine learning, and correlated to scratch wound closure and Boyden chamber chemotaxis. The classification accuracy was between 90% and 100% for the six pairwise cell line comparisons. Several phase parameters correlated with wound closure rate and chemotaxis across the four cell lines. The level of cell confluence in culture affected phase parameters in all cell lines tested. Results indicate that optical phase features of cell lines are a robust set of quantitative data of potential utility for phenotypic screening and prediction of motile behavior. © 2019 International Society for Advancement of Cytometry., (© 2019 International Society for Advancement of Cytometry.)

Intermediate filament (IF) proteins make up the largest family of cytoskeletal proteins in metazoans, and are traditionally known for their roles in fostering structural integrity in cells and tissues. Remarkably, individual IF genes are tightly regulated in a fashion that reflects the type of tissue, its developmental and differentiation stages, and biological context. In cancer, IF proteins serve as diagnostic markers, as tumor cells partially retain their original signature expression of IF proteins. However, there are also characteristic alterations in IF gene expression and protein regulation. The use of high throughput analytics suggests that tumor-associated alterations in IF gene expression have prognostic value. Parallel research is also showing that IF proteins directly and significantly impact several key cellular properties, including proliferation, death, migration, and invasiveness, with a demonstrated impact on the development, progression, and characteristics of various tumors. In this review, we draw from recent studies focused on three IF proteins most associated with cancer (keratins, vimentin, and nestin) to highlight how several "hallmarks of cancer" described by Hanahan and Weinberg are impacted by IF proteins. The evidence already in hand establishes that IF proteins function beyond their classical roles as markers and serve as effectors of tumorigenesis.

Objective: The purpose of this study was to evaluate the image quality of virtual monoenergetic images obtained from dual-layer-detector spectral CT of patients with metallic orthopedic implants of the distal radius., Materials and Methods: A retrospective analysis was performed between April 2016 and January 2017. Forty-three consecutively registered patients (33 women, 10 men; mean age, 50.7 ± 15.4 years) with metallic implants for distal radius fractures underwent dual-layer-detector spectral CT. Sixteen virtual monoenergetic image sets ranging from 50 to 200 keV were generated from the single slice with the most pronounced low-attenuation artifact from implants. Image quality was quantitatively assessed on the basis of the attenuation of the artifacts and reference tissue, background image noise, and artifact index. Qualitative assessment included degree of artifact, diagnostic image quality of the periimplant bones, and delineation of fracture lines. The Friedman rank sum test and kappa analysis were used for statistical analysis., Results: There were statistically significant differences in quantitative and qualitative parameters at different monoenergy levels (all p < 0.001). Artifact index was the lowest at 120 keV. Low-attenuation artifacts in the periimplant regions were least pronounced at 110 keV, and the diagnostic image quality of periimplant bone was best at 130 keV. Fracture lines were well delineated in all cases at 80-110 keV (p < 0.001)., Conclusion: The optimal energy setting for incurring the fewest metallic artifacts and obtaining the best diagnostic image quality from distal radius implants during dual-layer-detector spectral CT is the range of 110-130 keV.

Background: Sacral insufficiency fractures (SIFs) are a common cause of lower back pain in the elderly. However, because clinical symptoms are frequently vague and nonspecific and can mimic lumbar spine pathologies, initial imaging in SIF patients is frequently targeted at the lumbar spine rather than the sacrum, resulting in delayed diagnosis. The purpose of this study is to show the proportions of modalities used in diagnosing SIF in practice and to compare the clinical and imaging features of SIF diagnosed by lumbar spine MRI (L-spine MRI) with those diagnosed by non-lumbar imaging modalities (bone scan, pelvic bone CT, pelvis MRI)., Methods: Forty-two patients with SIF were enrolled in this study. SIFs diagnosed by L-spine were assigned to group 1 and SIFs diagnosed by non-lumbar imaging modalities (bone scan, pelvic bone CT, pelvis MRI) were assigned to group 2. The clinical and imaging features of SIFs were assessed and compared between two groups., Results: SIF were more commonly diagnosed by L-spine MRI (group 1: n = 27, 64.3%) than non-lumbar imaging modalities (group 2: n = 15, 35.7%), which was comprised of pelvic bone CT (n = 6, 14.3%), bone scan (n = 5, 11.9%), and pelvis MRI (n = 4, 9.5%). Lower back pain, radiating pain and comorbid other causes of pain were more frequently identified in group 1. Fracture involving bilateral sacral ala with horizontal component was the most common shape and S2 being the most commonly involved horizontal component, without significant difference between two groups., Conclusion: SIFs are more commonly diagnosed by L-spine MRI than non-lumbar imaging modalities, because of symptoms that mimic lumbar spine pathology and variable comorbid causes of pain. To know that L-spine MRI commonly reveal SIF and to be familiar with SIF features on L-spine MRI would help increase sensitivity in detecting this commonly underrecognized entity and achieve earlier and more appropriate management.

Angiolipoma is a benign soft tissue tumor with two subtypes: non-infiltrating and infiltrating. Although histologically benign, infiltrating angiolipoma can invade surrounding structures. The foot is a very rare location for angiolipoma, with only four cases reported in the English literature, including one infiltrating type. Here, we report a very rare case of infiltrating angiolipoma of the foot with magnetic resonance imaging (MRI) and ultrasonography (US) findings. A 7-year-old boy presented with a slowly growing foot mass. MRI showed an unencapsulated mass involving the third web space extending to the foot dorsum and sole. The mass was isointense to subcutaneous fat and was mixed with internal T1 low-signal-intensity enhancing areas. On US, we observed a heterogeneously hypoechoic mass with internal vascularity. Imaging and clinical features of angiolipoma and the radiologic differential diagnoses of a fat-containing mass in the pediatric foot are reviewed here. When there is an ill-defined foot mass with a fat component and variable enhancing portions in a child, infiltrating angiolipoma should be included in the differential diagnosis along with other fat-containing tumors.

Objective: To present magnetic resonance imaging (MRI) evidence of the regression or progression of chondroid tumors and to investigate whether MRI can be used to predict the evolution of chondroid tumors., Materials and Methods: Twenty-one patients with enchondromas or atypical cartilaginous tumors who had undergone extremity MRI at least twice with a minimum 12-month interval between the MRIs were enrolled in this study. The diagnosis was based on the radiography and MRI findings. We classified the tumors into the following three groups according to changes between the MRIs: no change (NC), progression (P), and regression (R). We assessed the initial MRI features, including anatomical location, size, endosteal scalloping, peritumoral edema, fat entrapment, and direction of progression or regression. Nineteen of the 21 patients had contrast-enhanced images, and we analyzed the presence of atypical lobular enhancement against typical peripheral or septal enhancement., Results: The R group comprised 11 cases (52%), the P group comprised five cases (24%), and the NC group comprised five cases (24%). None of the MRI features showed statistically significant differences among the groups. Atypical lobular enhancement was observed in the R (6 of 10, 60%) and NC (2 of 5, 40%) groups but not in the P group (0 of 4, 0%), although these differences were not statistically significant., Conclusions: Chondroid tumors can either regress or progress in the MRI follow-up. Atypical lobular enhancement was seen only in stable or regressing tumors.

The noninvasive, fast acquisition of quantitative phase maps using digital holographic microscopy (DHM) allows tracking of rapid cellular motility on transparent substrates. On two-dimensional surfaces in vitro, MDA-MB-231 cancer cells assume several morphologies related to the mode of migration and substrate stiffness, relevant to mechanisms of cancer invasiveness in vivo. The quantitative phase information from DHM may accurately classify adhesive cancer cell subpopulations with clinical relevance. To test this, cells from the invasive breast cancer MDA-MB-231 cell line were cultured on glass, tissue-culture treated polystyrene, and collagen hydrogels, and imaged with DHM followed by epifluorescence microscopy after staining F-actin and nuclei. Trends in cell phase parameters were tracked on the different substrates, during cell division, and during matrix adhesion, relating them to F-actin features. Support vector machine learning algorithms were trained and tested using parameters from holographic phase reconstructions and cell geometric features from conventional phase images, and used to distinguish between elongated and rounded cell morphologies. DHM was able to distinguish between elongated and rounded morphologies of MDA-MB-231 cells with 94% accuracy, compared to 83% accuracy using cell geometric features from conventional brightfield microscopy. This finding indicates the potential of DHM to detect and monitor cancer cell morphologies relevant to cell cycle phase status, substrate adhesion, and motility. © 2017 International Society for Advancement of Cytometry., (© 2017 International Society for Advancement of Cytometry.)

Objective: The purpose of this study was to differentiate malignant compression fractures from acute osteoporotic compression fractures of the spine by use of a Dixon MRI sequence to quantify fat fraction (FF)., Materials and Methods: Forty-four vertebral compression fractures were assessed with turbo spin-echo T1-weighted and six-echo Dixon sequences for FF quantification at 3-T MRI. The fractures were divided into malignant compression fractures (n = 24) and acute osteoporotic compression fractures (n = 20). Two radiologists independently measured quantitative parameters from ROIs in the fractures, including the T1 signal intensity of the fracture, the FF of the fracture, and the FF ratio (fracture FF divided by normal marrow FF). The mean values of the parameters were compared between the two groups, interobserver reliability between two radiologists was assessed, ROC curves were analyzed, and logistic regression analysis was performed., Results: The fracture FF and FF ratio of malignant compression fractures were significantly lower than those of acute osteoporotic compression fractures (fracture FF, 2.73% vs 14.36% [p < 0.001]; FF ratio, 0.05 vs 0.22 [p < 0.001]). There was no difference in T1 signal intensity of the fracture. The ROC AUC of fracture FF was 0.98 and of FF ratio was 0.95. In logistic regression analysis, fracture FF remained a significant variable that could be used to independently differentiate malignant from acute osteoporotic compression fractures (odds ratio, 0.33; p < 0.005)., Conclusion: FF and FF ratio obtained from FF maps obtained with a six-echo Dixon MRI sequence may be useful for differentiating acute osteoporotic compression fractures from malignant compression fractures.

Optical time-stretch imaging enables the continuous capture of non-repetitive events in real time at a line-scan rate of tens of MHz-a distinct advantage for the ultrafast dynamics monitoring and high-throughput screening that are widely needed in biological microscopy. However, its potential is limited by the technical challenge of achieving significant pulse stretching (that is, high temporal dispersion) and low optical loss, which are the critical factors influencing imaging quality, in the visible spectrum demanded in many of these applications. We present a new pulse-stretching technique, termed free-space angular-chirp-enhanced delay (FACED), with three distinguishing features absent in the prevailing dispersive-fiber-based implementations: (1) it generates substantial, reconfigurable temporal dispersion in free space (>1 ns nm -1 ) with low intrinsic loss (<6 dB) at visible wavelengths; (2) its wavelength-invariant pulse-stretching operation introduces a new paradigm in time-stretch imaging, which can now be implemented both with and without spectral encoding; and (3) pulse stretching in FACED inherently provides an ultrafast all-optical laser-beam scanning mechanism at a line-scan rate of tens of MHz. Using FACED, we demonstrate not only ultrafast laser-scanning time-stretch imaging with superior bright-field image quality compared with previous work but also, for the first time, MHz fluorescence and colorized time-stretch microscopy. Our results show that this technique could enable a wider scope of applications in high-speed and high-throughput biological microscopy that were once out of reach., Competing Interests: The authors declare no conflict of interest.

Our purpose was to evaluate the feasibility of using ultrasonographic criteria of thyroid capsular continuity and tumor contour to differentiate macroscopic extra-thyroidal extension (ETE) from microscopic ETE, as well as non-ETE from ETE. On ultrasonography, we evaluated thyroid capsular continuity (C0 = continuous, C1 = discontinuous, C2 = invisible), and thyroid tumor contour (P0 = in normal parenchyma, P1 = abutting, P2 = bulging), which were grouped into type 1-9 classifications. Either C1-2 or P1-2 was more prevalent in ETE than non-ETE. C1 and P2 tended to be associated with macroscopic ETE, whereas C0 and P1 were significantly associated with microscopic ETE. Types 6, 8 and 9 were more likely to have ETE than non-ETE; type 6 (C1 P2) and type 9 (C2 P2) were significantly associated with macroscopic ETE, whereas type 8 (C2 P1) was associated more with microscopic ETE. Macroscopic and microscopic ETE, as well as non-ETE and ETE, can be differentiated using these pre-operative ultrasonographic criteria., (Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Tachykinins (TKs) are a family of neurotransmitters that function as signaling molecules for such processes as maintaining homeostasis, regulating stress response, and modulating pain. TKs require the expression of at least one of three receptor subtypes: Neurokinin Receptor-1 (NKR-1), Neurokinin Receptor-2 (NKR-2), or Neurokinin Receptor-3 (NKR-3). We have isolated and cloned a portion of a gene coding for a tachykinin-like receptor from the nemertean Paranemertes sp. This 488-bp portion contains a short 101-bp segment that shares 85% similarity to the mouse substance-K receptor in Mus musculus and 83% similarity to the moth neuropeptide receptor A24 in Bombyx mori. Translated homology analysis aligning the coding sequence with the initial cytoplasmic carboxyl terminus of numerous G-protein coupled neuropeptide receptors also revealed 73% similarity to B. mori neuropeptide receptor A24. Our finding is the first report of a sequence amplified from Paranemertes sp. that may code for a small portion of a G-protein-coupled neuropeptide receptor with significant similarity to the TKR family, particularly the NKR-3 receptor isoform. This novel finding may open new avenues into exploring the role of tachykinin and its receptor in nemertean neurophysiology.

Purpose: To evaluate the value of precontrast phase (PP) of quadriphasic CT for differentiation of small arterial enhancing hepatocellular carcinoma (HCC) from non-tumorous arterioportal (AP) shunt in patients with chronic liver disease., Methods: Forty-eight patients with 28 HCCs and 28 AP shunts were enrolled. All lesions (5-20 mm) showed arterial hyperenhancement with isoattenuation on portal venous phase or delayed phase without typical features of AP shunt. We evaluated and analyzed the attenuation of the lesions with qualitative and quantitative methods in each phase. The size, location, shape, margin, and coexistent HCC were evaluated. Diagnostic performances were also compared with triphasic CT and quadriphasic CT including PP in prediction of AP shunts from HCCs., Results: The round or oval shape and visually low attenuation on PP were independent predictors for differentiating HCCs from AP shunts in multivariate analysis. Our study also revealed significantly increased diagnostic performances for both observers when PP was added to the triphasic CT., Conclusions: PP can be helpful in differentiation of small arterial enhancing HCCs from AP shunts. Careful evaluation of PP may lower need for follow-up CT or MRI, and can possibly achieve earlier diagnosis of small HCCs.

Expression of the intermediate filament protein keratin 17 (K17) is robustly upregulated in inflammatory skin diseases and in many tumors originating in stratified and pseudostratified epithelia. We report that autoimmune regulator (Aire), a transcriptional regulator, is inducibly expressed in human and mouse tumor keratinocytes in a K17-dependent manner and is required for timely onset of Gli2-induced skin tumorigenesis in mice. The induction of Aire mRNA in keratinocytes depends on a functional interaction between K17 and the heterogeneous nuclear ribonucleoprotein hnRNP K. Further, K17 colocalizes with Aire protein in the nucleus of tumor-prone keratinocytes, and each factor is bound to a specific promoter region featuring an NF-κB consensus sequence in a relevant subset of K17- and Aire-dependent proinflammatory genes. These findings provide radically new insight into keratin intermediate filament and Aire function, along with a molecular basis for the K17-dependent amplification of inflammatory and immune responses in diseased epithelia.

Objective: To retrospectively evaluate the conventional and functional (diffusion- or perfusion-weighted) magnetic resonance (MR) imaging features of ovarian fibroma, fibrothecoma, and thecoma., Materials and Methods: Histologically proven ovarian fibromas (n = 19), fibrothecomas (n = 7), and thecomas (n = 2) were reviewed (26 patients). The morphologic and signal intensity (SI) characteristics on conventional MR imaging (n = 28, all cases) were analyzed. The b 1000 signal intensity on diffusion-weighted image (DWI) (n = 22) and the time-to-signal intensity curve on perfusion-weighted image (PWI) (n = 7) were also analyzed. The presence and shape of the ipsilateral ovarian tissue surrounding the lesions were evaluated on T2-weighted image., Results: Twenty-two cases (79%) were predominantly solid tumor. Majority of the detected lesions exhibited the characteristic homogeneous low SI on T1- (24/28, 86%) and T2- (19/28, 68%) weighted image. Conversely, a number of lesions exhibited high SI (9/28, 32%) on T2-weighted image. Most lesions presented with a detectable ipsilateral ovary on T2-weighted image (24/28, 86%). Tumors larger than 6 cm more likely showed atypical morphology (mixed solid and cystic, cystic), atypical SI (high on T1- and T2-weighted image), and large amount ascites. Larger tumor group (>6 cm) was more likely diagnosed as fibrothecoma or thecoma than fibroma by pathology. On DWI, 16 lesions showed low b 1000 signal intensity (16/22, 73%). On PWI, all lesions showed curve type 1 or 2 (7/7, 100%), which tends to characterize benign lesions. All (16/16, 100%) pre-menopausal women had a detectable ipsilateral ovary, and six (60%) out of 10 post-menopausal women had a detectable ipsilateral ovary (p < 0.05)., Conclusions: Combining conventional morphologic and signal intensity characteristics with the findings from DWI or PWI might help differentiate ovarian fibroma, fibrothecoma, and thecoma from ovarian malignancy, although further prospective larger scale study using DWI and PWI is needed.

High levels of the intermediate filament keratin 17 (K17) correlate with a poor prognosis for several types of epithelial tumors. However, the causal relationship and underlying mechanisms remain undefined. A recent study suggested that K17 promotes skin tumorigenesis by fostering a specific type of inflammation. We report here that K17 interacts with the RNA-binding protein hnRNP K, which has also been implicated in cancer. K17 is required for the cytoplasmic localization of hnRNP K and for its role in regulating the expression of multiple pro-inflammatory mRNAs. Among these are the CXCR3 ligands CXCL9, CXCL10, and CXCL11, which together form a signaling axis with an established role in tumorigenesis. The K17-hnRNP K partnership is regulated by the ser/thr kinase RSK and required for CXCR3-dependent tumor cell growth and invasion. These findings functionally integrate K17, hnRNP K, and gene expression along with RSK and CXCR3 signaling in a keratinocyte-autonomous axis and provide a potential basis for their implication in tumorigenesis., (© 2015 Chung et al.)

Background: The small intestinal epithelium has an impressive ability to adapt to changes resulting from loss of length or alteration in dietary load. We sought to determine the potential influence of dietary protein absorption on growth and development. We hypothesized that a complex protein diet would improve growth over that of an elemental diet., Methods: Using the nematode Caenorhabditis elegans, a transparent worm with a rudimentary intestinal tube lined by enterocytes that function remarkably similar to humans, we measured daily growth, intestinal peptide, and amino acid transporter expression and intestinal proteolysis to compare the effects of a complex protein diet to a diet containing only amino acids., Results: Nematodes raised on a complex protein diet grew to adulthood faster than those raised solely on amino acids, which did not require an overall change in intestinal peptide or amino acid transporter expression. Despite no overall change in transporter expression, a shift in location of peptide transporter expression was noted between diets that corresponded to decreased rate of intestinal proteolysis seen in the complex protein-fed group., Conclusions: A complex protein diet stimulates in an altered pattern of intestinal peptide transporter expression and intestinal proteolytic activity that results in improved growth compared with a diet of elemental amino acids. This improved growth appears to be the result of increased efficiency of a smaller number of enterocytes. These data might be useful in targeting intestinal rehabilitation therapies for short bowel syndrome and other risk factors for intestinal failure., (© 2013 American Society for Parenteral and Enteral Nutrition.)

Epidermal growth factor receptor (EGFR) controls a wide range of cellular processes, and aberrant EGFR signaling as a result of receptor overexpression and/or mutation occurs in many types of cancer. Tumor cells in non-small cell lung cancer (NSCLC) patients that harbor EGFR kinase domain mutations exhibit oncogene addiction to mutant EGFR, which confers high sensitivity to tyrosine kinase inhibitors (TKIs). As patients invariably develop resistance to TKIs, it is important to delineate the cell biological basis of mutant EGFR-induced cellular transformation since components of these pathways can serve as alternate therapeutic targets to preempt or overcome resistance. NSCLC-associated EGFR mutants are constitutively-active and induce ligand-independent transformation in nonmalignant cell lines. Emerging data suggest that a number of factors are critical for the mutant EGFR-dependent tumorigenicity, and bypassing the effects of TKIs on these pathways promotes drug resistance. For example, activation of downstream pathways such as Akt, Erk, STAT3 and Src is critical for mutant EGFR-mediated biological processes. It is now well-established that the potency and spatiotemporal features of cellular signaling by receptor tyrosine kinases such as EGFR, as well as the specific pathways activated, is determined by the nature of endocytic traffic pathways through which the active receptors traverse. Recent evidence indicates that NSCLC-associated mutant EGFRs exhibit altered endocytic trafficking and they exhibit reduced Cbl ubiquitin ligase-mediated lysosomal downregulation. More recent work has shown that mutant EGFRs undergo ligand-independent traffic into the endocytic recycling compartment, a behavior that plays a key role in Src pathway activation and oncogenesis. These studies are beginning to delineate the close nexus between signaling and endocytic traffic of EGFR mutants as a key driver of oncogenic processes. Therefore, in this review, we will discuss the links between mutant EGFR signaling and endocytic properties, and introduce potential mechanisms by which altered endocytic properties of mutant EGFRs may alter signaling and vice versa as well as their implications for NSCLC therapy.

Differentiated thyroid carcinoma is uncommon in children and constitutes 0.5% to 3% of all pediatric malignancies. Few studies have reported imaging findings of childhood papillary thyroid carcinomas. We report 3 cases of papillary thyroid carcinomas in children. Among the 3 patients, the youngest was a 7-year-old girl. In the current report, we describe 2 cases of classic papillary thyroid carcinoma and 1 case of pediatric diffuse sclerosing variant of papillary thyroid carcinoma. The ultrasonographic features and diagnostic procedures in these pediatric patients are similar to those in adults.

Intermediate filaments (IFs) are assembled from a diverse group of evolutionarily conserved proteins and are specified in a tissue-dependent, cell type-dependent, and context-dependent fashion in the body. IFs are involved in multiple cellular processes that are crucial for the maintenance of cell and tissue integrity and the response and adaptation to various stresses, as conveyed by the broad array of crippling clinical disorders caused by inherited mutations in IF coding sequences. Accordingly, the expression, assembly, and organization of IFs are tightly regulated. Migration is a fitting example of a cell-based phenomenon in which IFs participate as both effectors and regulators. With a particular focus on vimentin and keratin, we here review how the contributions of IFs to the cell's mechanical properties, to cytoarchitecture and adhesion, and to regulatory pathways collectively exert a significant impact on cell migration., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

There is as yet no high-resolution data regarding the structure and organization of keratin intermediate filaments, which are obligate heteropolymers providing vital mechanical support in epithelia. We report the crystal structure of interacting 2B regions from the central coiled-coil domains of keratins 5 and 14 (K5 and K14), expressed in progenitor keratinocytes of epidermis. The interface of the K5-K14 coiled-coil heterodimer has asymmetric salt bridges, hydrogen bonds and hydrophobic contacts, and its surface exhibits a notable charge polarization. A trans-dimer homotypic disulfide bond involving Cys367 in K14's stutter region occurs in the crystal and in skin keratinocytes, where it is concentrated in a keratin filament cage enveloping the nucleus. We show that K14-Cys367 impacts nuclear shape in cultured keratinocytes and that mouse epidermal keratinocytes lacking K14 show aberrations in nuclear structure, highlighting a new function for keratin filaments.

Inkjet-printed Ag metallization is a promising method of forming front-side contacts on Si solar cells due to its non-contact printing nature and fine grid resolution. However, conventional Ag inks are unable to punch through the SiN(x) anti-reflection coating (ARC) layer on emitter Si surfaces. In this study, a novel formulation of Ag ink is examined for the formation of fire-through contacts on a SiN(x)-coated Si substrate using the single-step printing of Ag ink, followed by rapid thermal annealing at 800 degrees C. In order to formulate Ag inks with fire-through contact formation capabilities, a liquid etching agent was first formulated by dissolving metal nitrates in an organic solvent and then mixing the resulting solution with a commercial Ag nanoparticle ink at various volume ratios. During the firing process, the dissolved metal nitrates decomposed into metal oxides and acted in a similar manner to the glass frit contained in Ag pastes for screen-printed Ag metallization. The newly formulated ink with a 1 wt% loading ratio of metal oxides to Ag formed finely distributed Ag crystallites on the Si substrate after firing at 800 degrees C for 1 min.

Keratins are cytoplasmic intermediate filament proteins providing crucial structural support in epithelial cells. Keratin expression has diagnostic and even prognostic value in disease settings, and recent studies have uncovered modulatory roles for select keratin proteins in signaling pathways regulating cell growth and cell death. Elevated keratin expression in select cancers is correlated with higher expression of EGF receptor (EGFR), whose overexpression and/or mutation give rise to cancer. To explore the role of keratins in oncogenic signaling pathways, we examined the regulation of epithelial growth-associated keratin 17 (K17) in response to EGFR activation. K17 is specifically up-regulated in detergent-soluble fraction upon EGFR activation, and immunofluorescence analysis revealed alterations in K17-containing filaments. Interestingly, we identified AnxA2 as a novel interacting partner of K17, and this interaction is antagonized by EGFR activation. K17 and AnxA2 proteins show reciprocal regulation. Modulating expression of AnxA2 altered K17 stability, and AnxA2 overexpression delays EGFR-mediated change in K17 detergent solubility. Down-regulation of K17 expression, in turn, results in decreased AnxA2 phosphorylation at Tyr-23. These findings uncover a novel interaction involving K17 and AnxA2 and identify AnxA2 as a potential regulator of keratin filaments.

ESCRT pathway proteins play a key role in sorting ubiquitinated membrane receptors towards lysosomes providing an important mechanism for attenuating cell surface receptor signaling. However, recent studies point to a positive role of ESCRT proteins in signal transduction in multiple species studied under physiological and pathological conditions. ESCRT components such as Tsg101 and Hrs are overexpressed in human cancers and Tsg101 depletion is detrimental for cell proliferation, survival and transformed phenotype of tumor cells. However, the mechanisms underlying the positive contributions of ESCRT pathway to surface receptor signaling have remained unclear. In a recent study, we showed that Tsg101 and Vps4 are essential for translocation of active Src from endosomes to focal adhesion and invadopodia, thereby revealing a role of ESCRT pathway in promoting Src-mediated migration and invasion. We discuss the implications of these and other recent studies which together suggest a role for the ESCRT pathway in recycling of endocytic cargo proteins, aside from its role in lysosomal targeting, potentially explaining the positive roles of ESCRT proteins in signal transduction.

Non-malignant mammary epithelial cells (MECs) undergo acinar morphogenesis in three-dimensional Matrigel culture, a trait that is lost upon oncogenic transformation. Rho GTPases are thought to play important roles in regulating epithelial cell-cell junctions, but their contributions to acinar morphogenesis remain unclear. Here we report that the activity of Rho GTPases is down-regulated in non-malignant MECs in three-dimensional culture with particular suppression of Rac1 and Cdc42. Inducible expression of a constitutively active form of Vav2, a Rho GTPase guanine nucleotide exchange factor activated by receptor tyrosine kinases, in three-dimensional MEC culture activated Rac1 and Cdc42; Vav2 induction from early stages of culture impaired acinar morphogenesis, and induction in preformed acini disrupted the pre-established acinar architecture and led to cellular outgrowths. Knockdown studies demonstrated that Rac1 and Cdc42 mediate the constitutively active Vav2 phenotype, whereas in contrast, RhoA knockdown intensified the Vav2-induced disruption of acini, leading to more aggressive cell outgrowth and branching morphogenesis. These results indicate that RhoA plays an antagonistic role to Rac1/Cdc42 in the control of mammary epithelial acinar morphogenesis.

Background: Epidermal growth factor receptor (EGFR) controls a wide range of cellular processes, and altered EGFR signaling contributes to human cancer. EGFR kinase domain mutants found in non-small cell lung cancer (NSCLC) are constitutively active, a trait critical for cell transformation through activation of downstream pathways. Endocytic trafficking of EGFR is a major regulatory mechanism as ligand-induced lysosomal degradation results in termination of signaling. While numerous studies have examined mutant EGFR signaling, the endocytic traffic of mutant EGFR within the NSCLC milieu remains less clear., Results: This study shows that mutant EGFRs in NSCLC cell lines are constitutively endocytosed as shown by their colocalization with the early/recycling endosomal marker transferrin and the late endosomal/lysosomal marker LAMP1. Notably, mutant EGFRs, but not the wild-type EGFR, show a perinuclear accumulation and colocalization with recycling endosomal markers such as Rab11 and EHD1 upon treatment of cells with endocytic recycling inhibitor monensin, suggesting that mutant EGFRs preferentially traffic through the endocytic recycling compartments. Importantly, monensin treatment enhanced the mutant EGFR association and colocalization with Src, indicating that aberrant transit through the endocytic recycling compartment promotes mutant EGFR-Src association., Conclusion: The findings presented in this study show that mutant EGFRs undergo aberrant traffic into the endocytic recycling compartment which allows mutant EGFRs to engage in a preferential interaction with Src, a critical partner for EGFR-mediated oncogenesis.

Non-small cell lung cancer (NSCLC)-associated epidermal growth factor receptor (EGFR) mutants are constitutively active and induce ligand-independent transformation in non-malignant cell lines. We investigated the possibility that the ability of mutant EGFRs to transform cells reflects a constitutive cooperativity with Src using a system in which the overexpression of mutant, but not wild-type, EGFR induced anchorage-independent cell growth. Src was constitutively activated and showed enhanced interaction with mutant EGFRs, suggesting that constitutive EGFR-Src cooperativity may contribute to mutant EGFR-mediated oncogenesis. Indeed, the mutant EGFR-mediated cell transformation was inhibited by Src- as well as EGFR-directed inhibitors. Importantly, a tyrosine to phenylalanine mutation of the major Src phosphorylation site on EGFR, Y845, reduced the constitutive phosphorylation of NSCLC-EGFR mutants, as well as that of STAT3, Akt, Erk and Src, and reduced the mutant EGFR-Src association as well as proliferation, migration and anchorage-independent growth. Reduced anchorage-independent growth and migration were also observed when dominant-negative-Src was expressed in mutant EGFR-expressing cells. Overall, our findings show that mutant EGFR-Src interaction and cooperativity play critical roles in constitutive engagement of the downstream signaling pathways that allow NSCLC-associated EGFR mutants to mediate oncogenesis, and support the rationale to target Src-dependent signaling pathways in mutant EGFR-mediated malignancies.