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INTRODUCTION: Fine-needle aspiration cytology (FNAC) specimens are widely utilized for the diagnosis and molecular testing of various cancers. We performed a comparative proteomic analysis of three different sample types, including breast FNAC, core needle biopsy (CNB), and surgical resection tissues. Our goal was to evaluate the suitability of FNAC for in-depth proteomic analysis and for identifying potential therapeutic biomarkers in breast cancer. METHODS: High-throughput proteomic analysis was conducted on matched FNAC, CNB, and surgical resection tissue samples obtained from breast cancer patients. The protein identification, including currently established or promising therapeutic targets, was compared among the three different sample types. Gene Ontology (GO) enrichment analysis was also performed on all matched samples. RESULTS: Compared to tissue samples, FNAC testing revealed a comparable number of proteins (7,179 in FNAC; 7,196 in CNB; and 7,190 in resection samples). Around 85% of proteins were mutually identified in all sample types. FNAC, along with CNB, showed a positive correlation between the number of enrolled tumor cells and identified proteins. In the GO analysis, the FNAC samples demonstrated a higher number of genes for each pathway and GO terms than tissue samples. CCND1, CDK6, HER2, and IGF1R were found in higher quantities in the FNAC compared to tissue samples, while TUBB2A was only detected in the former. CONCLUSION: FNAC is suitable for high-throughput proteomic analysis, in addition to an emerging source that could be used to identify and quantify novel cancer biomarkers.
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To address the inherent brittleness of conventional transparent conductive oxides, researchers have focused on enhancing their flexibility. This is achieved by incorporating organic films to construct organic-inorganic hybrid layer-by-layer nanostructures, where the interlayer thickness and interface play pivotal roles in determining the properties. These factors are contingent on the type of material, processing conditions, and specific application requirements, making it essential to select the appropriate conditions. In this study, ZnO-zincone nanolaminate thin films were fabricated using atomic layer deposition and molecular layer deposition in various structural configurations. Transmission electron microscopy, X-ray diffraction, and scanning electron microscopy were used to conduct a thorough analysis of the thin-film growth and structural transformations resulting from the deposition conditions. Furthermore, the influence of structural differences at the interfaces on the mechanical properties of the films was investigated by employing both tensile and compression-bending fatigue tests. This comprehensive examination reveals noteworthy variations in the mechanical responses of the films. Thin films characterized by internal porosity and an intermixed amorphous structure demonstrated enhanced compressive toughness, whereas rigid organic layers improved flexibility. These findings offer valuable insights into the development of flexible, transparent multilayer films.
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The N-degron pathway determines the half-life of proteins by selectively destabilizing the proteins bearing N-degrons. N-terminal glutamine amidohydrolase 1 (NTAQ1) plays an essential role in the arginine N-degron (Arg/N-degron) pathway as an initializing enzyme via the deamidation of the N-terminal (Nt) glutamine (Gln). However, the Nt-serine-bound conformation of hNTAQ1 according to the previously identified crystal structure suggests the possibility of other factors influencing the recognition of Nt residues by hNTAQ1. Hence, in the current study, we aimed to further elucidate the substrate recognition of hNTAQ1; specifically, we explored 12 different substrate-binding conformations of hNTAQ1 depending on the subsequent residue of Nt-Gln. Results revealed that hNTAQ1 primarily interacts with the protein Nt backbone, instead of the side chain, for substrate recognition. Here, we report that the Nt backbone of proteins appears to be a key component of hNTAQ1 function and is the main determinant of substrate recognition. Moreover, not all second residues from Nt-Gln, but rather distinctive and charged residues, appeared to aid in detecting substrate recognition. These new findings define the substrate-recognition process of hNTAQ1 and emphasize the importance of the subsequent Gln residue in the Nt-Gln degradation system. Our extensive structural and biochemical analyses provide insights into the substrate specificity of the N-degron pathway and shed light on the mechanism underlying hNTAQ1 substrate recognition. An improved understanding of the protein degradation machinery could aid in developing therapies to promote overall health through enhanced protein regulation, such as targeted protein therapies.
Assuntos
Arginina , Humanos , Especificidade por Substrato , Arginina/química , Arginina/metabolismo , Modelos Moleculares , Glutamina/metabolismo , Glutamina/química , Amidoidrolases/química , Amidoidrolases/metabolismo , Amidoidrolases/genética , Conformação Proteica , Proteólise , DegronsRESUMO
The accurate diagnosis of papillary urothelial carcinoma (PUC) is frequently challenging due to benign mimickers. Other than morphology-based diagnostic criteria, reliable biomarkers for differentiating benign and malignant papillary urothelial neoplasms remain elusive, so we sought to discover new markers to address this challenge. We first performed tandem mass spectrometry-based quantitative proteomics using diverse papillary urothelial lesions, including PUC, urothelial papilloma (UP), inverted urothelial papilloma, and cystitis cystica. We prioritized potential diagnostic biomarkers using machine learning, and subsequently validated through immunohistochemistry (IHC) in two independent cohorts. Metabolism, transport, cell cycle, development, and immune response functions were differentially enriched between malignant and benign papillary neoplasms. RhoB and NT5DC2 were shortlisted as optimal candidate markers for PUC diagnosis. In our pilot study using IHC, NT5DC2 was subsequently selected as its expression consistently differed in PUC (p = 0.007). Further validation of NT5DC2 using 49 low-grade (LG) urothelial lesions, including 15 LG-PUCs and 17 UPs, which are the most common mimickers, concordantly revealed lower IHC expression levels in LG-PUC (p = 0.0298). Independent external validation with eight LG-PUCs and eight UPs confirmed the significant downregulation of NT5DC2 in LG-PUC (p = 0.0104). We suggest that NT5DC2 is a potential IHC biomarker for differentiating LG-PUC from its benign mimickers, especially UP.
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A 2 mm resection margin is considered adequate for ductal carcinoma in situ (DCIS). We assessed the effectiveness of a tailored radiation dose for margins < 2 mm and the appropriate margin width for high-risk DCIS. We retrospectively evaluated 137 patients who received adjuvant radiotherapy after breast-conserving surgery for DCIS between 2013 and 2019. The patients were divided into three- positive, close (< 2 mm), and negative (≥ 2 mm) margin groups. Radiation dose to the tumor bed in equivalent dose in 2 Gy fractions were a median of 66.25 Gy, 61.81 Gy, and 59.75 Gy for positive, close, and negative margin groups, respectively. During a median follow-up of 58 months, the crude rates of local recurrence were 15.0%, 6.7%, and 4.6% in the positive, close, and negative margin groups, respectively. The positive margin group had a significantly lower 5-year local recurrence-free survival (LRFS) rate compared to the close and negative margin groups in propensity-weighted log-rank analysis (84.82%, 93.27%, and 93.20%, respectively; p = 0.008). The difference in 5-year LRFS between patients with the high- and non-high-grade tumors decreased as the margin width increased (80.4% vs. 100.0% for margin ≥ 2 mm, p < 0.001; 92.3% vs. 100.0% for margin ≥ 6 mm, p = 0.123). With the radiation dose tailored for margin widths, positive margins were associated with poorer local control than negative margins, whereas close margins were not. Widely clear margins (≥ 2 mm) were related to favorable local control for high-grade DCIS.