Distal symmetric polyneuropathy (DSPN) is the most common form of diabetic neuropathy and a major cause of morbidity in patients with diabetes. Despite extensive research, diagnostic advances have been incremental rather than transformative, and accurate diagnoses in clinical practice still rely on careful clinical assessments. This review focuses on diagnostic approaches for DSPN that can be applied in routine neurological practice. We summarize the evolving definition and diagnostic criteria of DSPN, including the graded classification proposed by the Toronto consensus panel. Core diagnostic elements such as detailed history-taking, bedside neurological examinations, and validated clinical scoring systems are reviewed. We also discuss the role and limitations of nerve conduction studies, skin biopsy, corneal confocal microscopy, and tests of small-fiber function. Laboratory evaluations for differential diagnoses and current American Diabetes Association screening recommendations are also discussed.

Purpose: We aimed to compare broad-spectrum antibiotic use between hospice and nonhospice patients with cancer at the end of life using nationwide data from Korea. Methods: In this retrospective cohort study, we analyzed the Korean National Health Insurance Service data of adult patients with cancer who died between 2018 and 2021. Hospice users were defined as patients who received inpatient, home-based, or consultation-based hospice care before death. We applied propensity score matching (1:2) to balance the baseline characteristics of the hospice and non-hospice groups. Broad-spectrum antibiotic use, including anti-pseudomonal penicillins, anti-pseudomonal cephalosporins, carbapenems, and glycopeptides, was assessed during the last 3 months of life using prescription proportions and days of therapy per 1,000 patient-days. Results: After matching, 38,102 hospice and 75,736 non-hospice users were analyzed. During the last 3 months of life, 74.6% of hospiceand 79.0% of non-hospice users received at least one broad-spectrum antibiotic (P＜0.001).The proportion of patients receiving broad-spectrum antibiotics was generally lower amonghospice users across all time intervals (P＜0.001), and the number of days of therapy wasalso lower, with the largest differences observed during the final week and last 3 days of life.Subgroup analyses showed the highest antibiotic exposure among patients with hematologic and pancreatobiliary cancers, particularly in the non-hospice group. Conclusion Hospice involvement was associated with lower use and reduced exposure to broad-spectrum antibiotics among patients with cancer near the end of life. These findings support the alignment of end-of-life treatment decisions with the comfort-oriented goals of hospice care.

The recent approval of trastuzumab deruxtecan for human epidermal growth factor receptor 2 (HER2)–low and HER2-ultralow breast cancer mandates an adequate assessment of these categories. Methods: Seven breast pathologists from the Breast Pathology Study Group of the Korean Society of Pathologists held an on-site expert consensus meeting. Fifteen sets of virtual whole slide images (WSI) of hematoxylin and eosin stain and HER2 immunohistochemistry were provided. The pathologists were given 60 minutes to submit their diagnosis of HER2 expression into null, ultralow, 1+, 2+, or 3+. Afterwards, in-depth discussion and consensus diagnoses were made by real-time visualization of the WSI. Results: After the consensus meeting, unanimous 100% agreements were seen only in five (33.3%) of the examined cases, which consisted of three 1+ cases and two 2+ cases. Two cases (13.3%) had mild disagreement, with only one pathologist’s disagreement. Of note, eight cases (53.3%) showed significant disagreement, defined by more than two pathologists’ disagreement. All HER2-null cases were reclassified as ultralow after consensus review, suggesting potential widespread underclassification of ultralow cases in clinical practice. Conclusions: Experts had significant discrepancies in interpreting HER2-low/ultralow status. It is important to assess if the distinction between HER2-low and ultralow is strictly required and if HER2-null breast cancer exists in reality.

Objective: This study aimed to evaluate the feasibility, safety, and oncologic outcomes of irreversible electroporation (IRE) using a clustered electrode in patients with locally advanced pancreatic cancer (LAPC). Materials and Methods: In this single-center prospective cohort study, 13 patients with LAPC (median age, 60 years; range, 48–78 years) underwent clustered electrode IRE between September 2022 and September 2024. Patient characteristics, procedural details, and clinical outcomes were recorded. Endpoints included technical success, procedure-related complications, overall survival (OS), and progression-free survival (PFS). Results: Tumors were located in the pancreatic head in four patients (30.8%) and in the body/tail in nine (69.2%). The median tumor size was 2.4 cm (1.5–4.0 cm), and vascular invasion was present in all patients. Technical success was achieved in all patients. Intraoperative IRE was performed in 11 (84.6%) patients, and 2 (15.4%) patients underwent percutaneous IRE. Gastrointestinal bleeding events as major complications occurred in two patients (15.4%) and, both were successfully controlled by embolization. No 60-day mortality was observed. At a median follow-up of 24.5 months (range, 9.9–33.4 months) after IRE, median OS and PFS from IRE were 20.1 and 14.5 months, respectively. Conclusion IRE using clustered electrodes for LAPC appears to be a feasible therapeutic approach, offering reliable technical success and acceptable safety. Survival outcomes are encouraging; however, larger, controlled studies are required.

Mutations in p53 have been implicated in poor prognosis and reduced sensitivity to 5-fluorouracil (5-FU) treatment in colon cancer.While p53-dependent mechanisms have been widely studies, less is known about how p53 deficiency reshapes cellular signaling and contributes to 5-FU resistance. In this study, we aimed to profile proteomic alterations associated with p53 loss by comparing colon cancer cells with and without p53 expression. Differentially expressed proteins (DEPs) related to cell cycle regulation were of particular interest, as 5-FU treatment induced G1 phase arrest in HCT116 p53 wild-type (WT) cells, whereas p53 knockout (KO) cells predominantly showed S phase arrest. We identified several DEPs in p53 deficient cells following 5-FU treatment. Notably, F3 expression was increased, while aldehyde dehydrogenase family 1 member A4 (ALDH1A3), histone deacetylase 2 (HDAC2), and protein S100-A4 (S100A4) were decreased. The expression levels of these genes were associated with overall survival in patients with colon cancer. These findings highlight proteomic alterations linked to p53 deficiency and support a proposed model in which differential regulation of specific proteins may be associated with reduced sensitivity to 5-FU, providing a basis for future mechanistic and functional studies.

Osteoarthritis (OA) is a prevalent, chronic joint disorder characterized by cartilage degradation, synovial inflammation, and extracellular matrix (ECM) remodeling, yet disease-modifying therapies remain elusive. Emerging evidence implicates ferroptosis, an iron-dependent form of regulated cell death driven by lipid peroxidation, and cellular senescence, characterized by growth arrest and a senescence-associated secretory phenotype (SASP), as central contributors to OA pathogenesis. Ferroptotic chondrocytes release reactive lipid species and damage-associated molecular patterns (DAMPs) that induce paracrine senescence in neighboring cells, while senescent cells amplify oxidative stress and ferroptotic susceptibility, forming a self-perpetuating feed-forward loop that accelerates tissue degeneration. Histological, molecular, and in vivo studies demonstrate iron accumulation, lipid peroxidation, glutathione peroxidase 4 (GPX4) depletion, and SASP factor secretion in human OA cartilage, synovium, and animal models, linking these processes to ECM breakdown and joint inflammation. Targeted interventions, alone or in combination, can disrupt this pathological loop, preserve chondrocyte viability, reduce SASP-mediated inflammation, and mitigate cartilage damage. Integration of biomarker-guided patient stratification, advanced imaging, and spatial transcriptomic profiling may enable precision-targeted, disease-modifying therapies. Therefore, elucidating the crosstalk between ferroptosis and senescence offers a conceptual and translational framework for shifting OA management from symptomatic relief toward preservation of joint integrity and long-term disease modification.

Background: Posterior fossa group A (PFA) ependymoma is a lethal pediatric brain tumor drivenpredominantly by epigenetic dysregulation. Enhancer of Zeste Homologs Inhibitory Protein (EZHIP) is a defining oncogenic factor in PFA ependymoma that inhibits PRC2 activity, inducing a global loss of H3K27me3 and sustaining aberrant developmental transcriptional programs. Although the metabolic modulator, metformin, reduces EZHIP protein levels, the mechanisms governing EZHIP regulation remain undefined. Methods: We generated a stable HEK293T reporter cell expressing HA- and RFP-taggedEZHIP together with a GFP viability control, enabling quantitative and viability-normalized assessment of EZHIP abundance. In silico post-translational modification prediction was performed using PhosphoSitePlus and NetPhos 3.1 to identify candidate regulatory residues and upstream kinases. A focused panel of pathway targeting compounds was evaluated using fluorescence-based high-throughput screening, followed by secondary validation including cell counting, LC 50 (half-maximal lethal concentration) analysis, and Western blotting. Results: Computational analyses identified multiple high-confidence serine phosphorylationsites on EZHIP and implicated AMPK, MAPK, PKC, AKT, and CK2 signaling pathways. High-throughput screening revealed that activation of the AMPK axis robustly suppressed EZHIP protein levels.Secondary validation demonstrated that biguanides activating AMPK reduced EZHIP abundance independently of cytotoxicity and restored global H3K27me3 levels. In contrast, PKC activation increased EZHIP protein abundance. Conclusion Our study identifies EZHIP as a dynamically regulated oncoprotein controlled by post-translational signaling pathways. AMPK and PKC exert opposing effects on EZHIP stability, defining actionable regulatory mechanisms for therapeutic targeting in EZHIP-driven cancers.

Purpose: Human epidermal growth factor receptor 2 (HER2) is amplified or overexpressed in various malignancies, including breast and gastric cancers, and is associated with poor prognosis. Although HER2-targeted therapies, such as trastuzumab, improve outcomes in HER2-positive tumors, resistance often develops, and HER2-low tumors remain largely untargeted. Trastuzumab deruxtecan (T-DXd; DS-8201a) is a HER2-targeted antibody-drug conjugate with potent activity in HER2-positive and HER2-low tumors. This study evaluates its antitumor mechanisms and efficacy in HER2-positive, HER2-low, and homologous recombination deficiency (HRD)–associated models. Materials and Methods: Effects of T-DXd were assessed in cancer cell lines with diverse HER2 expression and HRD status. In vivo efficacy was evaluated using a xenograft model derived from HER2-low SNU-601 gastric cancer cells. Results: T-DXd reduced HER2 phosphorylation and downstream signaling (AKT, ERK) in HER2-positive cells. It induced DNA damage accumulation, as evidenced by increased γH2AX and p-Chk1 expression, and triggered apoptosis through cleaved poly(ADP-ribose) polymerase and caspase-3 activation, confirmed by annexin V staining. Similar effects were observed in HER2-low cells, with greater sensitivity in HRD cells. In xenografts, T-DXd reduced tumor volume by up to 80% at 4 mg/kg and 10 mg/kg. Histological analyses showed decreased Ki-67 and increased apoptosis. Furthermore, T-DXd induced G2/M cell cycle arrest and nuclear anaplasia, suggesting disruption of chromosomal stability as a potential antitumor mechanism. No significant toxicity, including body weight loss, was observed. Conclusion These findings highlight T-DXd’s effectiveness in HER2-low and HRD tumors, supporting its broader clinical application, including strategies targeting DNA damage repair pathways.

Human epidermal growth factor receptor 2 (HER2) has evolved from a poor prognostic factor to one of the most impactful predictive biomarkers in oncology. The introduction of trastuzumab established HER2 as a binary determinant of therapy, with HER2 immunohistochemistry (IHC) becoming the treatment-guiding diagnostic assay. However, the emergence of antibody-drug conjugates (ADCs), particularly trastuzumab deruxtecan, has challenged this paradigm by demonstrating activity in tumors with low and even ultralow HER2 expression. This review outlines the evolution of HER2 testing, from its historical discovery and early assay variability to the ADC era, where categories such as HER2-low and HER2-ultralow have emerged. We highlight key challenges: poor reproducibility at the lower end of IHC scoring, instability of HER2 status across timepoints and between primary and metastatic tumors, and no consistent biological distinction between low, ultralow, and null. Efforts to improve reliability—including structured training, high-sensitivity assays, RNA-based methods, and artificial intelligence-assisted pathology—are summarized. Finally, we reconsider the therapeutic implications of ADCs, with the question of whether the benefit parallels HER2 expression or extends into HER2-null disease. HER2 exemplifies how biomarker interpretation evolves with drug development. As new ADCs target additional antigens, pathologists must balance trial-driven categories with biologic reproducibility to ensure diagnostics remain aligned with therapeutic advances.

Purpose: Medical artificial intelligence (AI) is rapidly being integrated into clinical practice and healthcare systems, raising concerns regarding safety, accountability, and governance. Despite its increasing importance, empirical comparative studies examining differences in perceptions of medical AI among key expert groups remain limited. This study aimed to compare and analyze perceptions of medical AI among medical and non-medical professionals and to systematically identify commonalities and differences across policy- and governance-relevant domains. Methods: Focus group interviews using open-ended questions were conducted with 30 experts (15 medical and 15 non-medical professionals) who had direct experience with medical AI. Data were analyzed using inductive thematic analysis combined with qualitative comparative analysis. Analytical rigor was strengthened through independent coding and consensus-based discussions. Results: Both groups recognized the potential of medical AI to bring meaningful changes to healthcare systems. However, medical professionals primarily evaluated medical AI in terms of clinical applicability, patient safety, explainability, and accountability. In contrast, non-medical professionals emphasized technological maturity, scalability, data infrastructure, standardization, and system-integration potential. Group-specific patterns also emerged regarding perceived limitations, autonomy, educational priorities, and classification frameworks, particularly in relation to clinical risk management versus system-level design and governance considerations. Conclusion: Differences in perceptions of medical AI are systematically associated with distinct interpretive frames shaped by professional roles and responsibility structures. Effective implementation and policy design for medical AI therefore require an integrated approach that accounts for these structural differences. This study provides empirical evidence and a conceptual foundation for future quantitative and mixed-methods research on medical AI governance.