ChatGPT's Response Consistency: A Study on Repeated Queries of Medical Examination Questions.

(1) Background: As the field of artificial intelligence (AI) evolves, tools like ChatGPT are increasingly integrated into various domains of medicine, including medical education and research. Given the critical nature of medicine, it is of paramount importance that AI tools offer a high degree of reliability in the information they provide. (2) Methods: A total of n = 450 medical examination questions were manually entered into ChatGPT thrice, each for ChatGPT 3.5 and ChatGPT 4. The responses were collected, and their accuracy and consistency were statistically analyzed throughout the series of entries. (3) Results: ChatGPT 4 displayed a statistically significantly improved accuracy with 85.7% compared to that of 57.7% of ChatGPT 3.5 (p < 0.001). Furthermore, ChatGPT 4 was more consistent, correctly answering 77.8% across all rounds, a significant increase from the 44.9% observed from ChatGPT 3.5 (p < 0.001). (4) Conclusions: The findings underscore the increased accuracy and dependability of ChatGPT 4 in the context of medical education and potential clinical decision making. Nonetheless, the research emphasizes the indispensable nature of human-delivered healthcare and the vital role of continuous assessment in leveraging AI in medicine.

Monitoring mepolizumab treatment in chronic rhinosinusitis with nasal polyps (CRSwNP): Discontinue, change, continue therapy?

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease of the mucous membranes of the nose and sinuses. Eosinophilic inflammation is described as a common endotype. The anti-IL-5 antibody mepolizumab was approved in November 2021 as an add-on therapy to intranasal glucocorticosteroids for the treatment of adults with severe chronic rhinosinusitis with nasal polyps when systemic glucocorticosteroids or surgery do not provide adequate disease control. While national and international recommendations exist for the use of mepolizumab in CRSwNP, it has not yet been adequately specified how this therapy should be monitored, what follow-up documentation is necessary, and when it should be discontinued if necessary. MATERIALS AND METHODS: A literature search was performed to analyze previous data on the treatment of CRSwNP with mepolizumab and to determine the available evidence by searching Medline, Pubmed, the national and international trial and guideline registries, and the Cochrane Library. Human studies published in the period up to and including 10/2022 were considered. RESULTS: Based on the international literature and previous experience by an expert panel, recommendations for follow-up, adherence to therapy intervals, and possible therapy breaks as well as discontinuation of therapy when using mepolizumab for the indication CRSwNP in the German healthcare system are given on the basis of a documentation sheet. CONCLUSION: Understanding the immunological basis of CRSwNP opens up new non-surgical therapeutic approaches with biologics for patients with severe, uncontrolled courses. Here, we provide recommendations for follow-up, adherence to therapy intervals, possible therapy pauses, or discontinuation of therapy when mepolizumab is used as add-on therapy with intranasal glucocorticosteroids to treat adult patients with severe CRSwNP that cannot be adequately controlled with systemic glucocorticosteroids and/or surgical intervention.

Head and neck cancer of unknown primary: unveiling primary tumor sites through machine learning on DNA methylation profiles.

BACKGROUND: The unknown tissue of origin in head and neck cancer of unknown primary (hnCUP) leads to invasive diagnostic procedures and unspecific and potentially inefficient treatment options for patients. The most common histologic subtype, squamous cell carcinoma, can stem from various tumor primary sites, including the oral cavity, oropharynx, larynx, head and neck skin, lungs, and esophagus. DNA methylation profiles are highly tissue-specific and have been successfully used to classify tissue origin. We therefore developed a support vector machine (SVM) classifier trained with publicly available DNA methylation profiles of commonly cervically metastasizing squamous cell carcinomas (n = 1103) in order to identify the primary tissue of origin of our own cohort of squamous cell hnCUP patient's samples (n = 28). Methylation analysis was performed with Infinium MethylationEPIC v1.0 BeadChip by Illumina. RESULTS: The SVM algorithm achieved the highest overall accuracy of tested classifiers, with 87%. Squamous cell hnCUP samples on DNA methylation level resembled squamous cell carcinomas commonly metastasizing into cervical lymph nodes. The most frequently predicted cancer localization was the oral cavity in 11 cases (39%), followed by the oropharynx and larynx (both 7, 25%), skin (2, 7%), and esophagus (1, 4%). These frequencies concord with the expected distribution of lymph node metastases in epidemiological studies. CONCLUSIONS: On DNA methylation level, hnCUP is comparable to primary tumor tissue cancer types that commonly metastasize to cervical lymph nodes. Our SVM-based classifier can accurately predict these cancers' tissues of origin and could significantly reduce the invasiveness of hnCUP diagnostics and enable a more precise therapy after clinical validation.

Integrated Molecular and Histological Insights for Targeted Therapies in Mesenchymal Sinonasal Tract Tumors.

PURPOSE OF REVIEW: This review aims to provide a comprehensive overview of mesenchymal sinonasal tract tumors (STTs), a distinct subset of STTs. Despite their rarity, mesenchymal STTs represent a unique clinical challenge, characterized by their rarity, often slow progression, and frequently subtle or overlooked symptoms. The complex anatomy of the sinonasal area, which includes critical structures such as the orbit, brain, and cranial nerves, further complicates surgical treatment options. This underscores an urgent need for more advanced and specialized therapeutic approaches. RECENT FINDINGS: Advancements in molecular diagnostics, particularly in next-generation sequencing, have significantly enhanced our understanding of STTs. Consequently, the World Health Organization has updated its tumor classification to better reflect the distinct histological and molecular profiles of these tumors, as well as to categorize mesenchymal STTs with greater accuracy. The growing understanding of the molecular characteristics of mesenchymal STTs opens new possibilities for targeted therapeutic interventions, marking a significant shift in treatment paradigms. This review article concentrates on mesenchymal STTs, specifically addressing sinonasal tract angiofibroma, sinonasal glomangiopericytoma, biphenotypic sinonasal sarcoma, and skull base chordoma. These entities are marked by unique histopathological and molecular features, which challenge conventional treatment approaches and simultaneously open avenues for novel targeted therapies. Our discussion is geared towards delineating the molecular underpinnings of mesenchymal STTs, with the objective of enhancing therapeutic strategies and addressing the existing shortcomings in the management of these intricate tumors.

Isothiocyanates in medicine: A comprehensive review on phenylethyl-, allyl-, and benzyl-isothiocyanates.

In recent years, isothiocyanates (ITCs), bioactive compounds primarily derived from Brassicaceae vegetables and herbs, have gained significant attention within the biomedical field due to their versatile biological effects. This comprehensive review provides an in-depth exploration of the therapeutic potential and individual biological mechanisms of the three specific ITCs phenylethyl isothiocyanate (PEITC), allyl isothiocyanate (AITC), and benzyl isothiocyanate (BITC), as well as their collective impact within the formulation of ANGOCIN® Anti-Infekt N (Angocin). Angocin comprises horseradish root (Armoracia rusticanae radix, 80 mg) and nasturtium (Tropaeoli majoris herba, 200 mg) and is authorized for treating inflammatory diseases affecting the respiratory and urinary tract. The antimicrobial efficacy of this substance has been confirmed both in vitro and in various clinical trials, with its primary effectiveness attributed to ITCs. PEITC, AITC, and BITC exhibit a wide array of health benefits, including potent anti-inflammatory, antioxidant, and antimicrobial properties, along with noteworthy anticancer potentials. Moreover, we highlight their ability to modulate critical biochemical pathways, such as the nuclear factor erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and signal transducer and activator of transcription (STAT) pathways, shedding light on their involvement in cellular apoptosis and their intricate role to guide immune responses.

Crosstalk Between NK Cell Receptors and Tumor Membrane Hsp70-Derived Peptide: A Combined Computational and Experimental Study.

Natural killer (NK) cells are central components of the innate immunity system against cancers. Since tumor cells have evolved a series of mechanisms to escape from NK cells, developing methods for increasing the NK cell antitumor activity is of utmost importance. It is previously shown that an ex vivo stimulation of patient-derived NK cells with interleukin (IL)-2 and Hsp70-derived peptide TKD (TKDNNLLGRFELSG, aa450-461) results in a significant upregulation of activating receptors including CD94 and CD69 which triggers exhausted NK cells to target and kill malignant solid tumors expressing membrane Hsp70 (mHsp70). Considering that TKD binding to an activating receptor is the initial step in the cytolytic signaling cascade of NK cells, herein this interaction is studied by molecular docking and molecular dynamics simulation computational modeling. The in silico results showed a crucial role of the heterodimeric receptor CD94/NKG2A and CD94/NKG2C in the TKD interaction with NK cells. Antibody blocking and CRISPR/Cas9-mediated knockout studies verified the key function of CD94 in the TKD stimulation and activation of NK cells which is characterized by an increased cytotoxic capacity against mHsp70 positive tumor cells via enhanced production and release of lytic granules and pro-inflammatory cytokines.

A Retrospective Analysis of Long-Term Prophylaxis with Berotralstat in Patients with Hereditary Angioedema and Acquired C1-Inhibitor Deficiency-Real-World Data.

Hereditary angioedema (HAE) and acquired C1-inhibitor deficiency (AAE-C1-INH) are orphan diseases. Berotralstat is a recently licensed long-term prophylaxis (LTP) and the first oral therapy for HAE patients. No approved therapies exist for AAE-C1-INH patients. This study is the first to report real-world clinical data of patients with AAE-C1-INH and HAE who received Berotralstat. All patients treated with Berotralstat were included in this retrospective, bi-centric study. Data was collected from patients' attack calendars and the angioedema quality of life (AE-QoL) and angioedema control test (AECT) questionnaires before treatment, and at 3, 6, and 12 months after treatment and was then analyzed. Twelve patients were included, 3 patients with AAE-C1-INH, 7 patients with HAE type I, and 2 patients with HAE-nC1-INH. One patient (HAE I) quit treatment. Berotralstat was associated with fewer attacks in all groups. After 6 months of treatment, a median decrease of attacks per month was noted for HAE type I patients (3.3 to 1.5) and AAE-C1-INH patients (2.3 to 1.0). No aerodigestive attacks were noted for AAE-C1-INH patients. For HAE-nC1-INH patients, a mean decrease from 3.8 to 1.0 was noted (3 months). For HAE I patients, the total AE-QoL lowered a mean of 24.1 points after 6 months, for HAE-nC1-HAE patients 8.0 points, and for AAE-C1-INH patients 13.7 points. AECT scores increased for HAE I patients (mean: 7.1), HAE-nC1-INH patients (9.0), and AAE-C1-INH patients (4.2) after 6 months. Patients with HAE, HAE-nC1-INH, and AAE-C1-INH treated with Berotralstat showed reduced angioedema attacks and improved AE-QoL and AECT scores.

Acquired Angioedema Due to C1-Inhibitor Deficiency (AAE-C1-INH)-A Bicenter Retrospective Study on Diagnosis, Course, and Therapy.

BACKGROUND: Acquired angioedema with C1-inhibitor deficiency (AAE-C1-INH) is a rare condition resembling hereditary angioedema (HAE), but with late onset and low C1-inhibitor (C1-INH) due to consumption potentially caused by autoimmune diseases and mainly lymphatic malignancies. Being about 10-fold rarer than HAE, there is limited knowledge and no licensed therapy. OBJECTIVE: To report clinical and biological data from a newly described population of 20 patients with AAE-C1-INH assessing diagnostic delay, AAE-C1-INH:HAE-ratio, underlying conditions, and therapeutic management in Germany. METHODS: Retrospective data analysis of 20 patients from 2 angioedema centers in southern Germany. RESULTS: Median age at symptoms' onset was 64 years (60% females), with predominant swellings of the face (85%) and low levels for C1-INH in almost all patients. The ratio AAE-C1-INH:HAE was 1:9.7. From symptoms' onset to diagnosis of AAE-C1-INH, the median delay was 7.5 months, and between AAE-C1-INH symptoms' onset and diagnosis of the underlying hematological condition (n = 9) it was 4 months (median). Four patients had a history of solid neoplasm, 1 had a papillary thyroid carcinoma as the only potential cause for AAE-C1-INH, with treatment of the malignancy resulting in resolution of AAE-C1-INH. All the symptomatic patients were treated with off-label on-demand icatibant subcutaneously or C1-INH concentrate intravenously, and 6 severely affected patients needed off-label long-term prophylaxis with good symptom control. CONCLUSIONS: AAE-C1-INH is characterized by late-onset swellings mainly involving the face and low C1-INH levels. Diagnostic delay for AAE-C1-INH is further decreasing despite being about 10-fold rarer than HAE. Patients severely affected without underlying condition or no indication for treatment could benefit from off-label therapy.

1,8-cineole (eucalyptol): A versatile phytochemical with therapeutic applications across multiple diseases.

1,8-cineole (Eucalyptol), a naturally occurring compound derived from botanical sources such as eucalyptus, rosemary, and camphor laurel, has a long history of use in traditional medicine and exhibits an array of biological properties, including anti-inflammatory, antioxidant, antimicrobial, bronchodilatory, analgesic, and pro-apoptotic effects. Recent evidence has also indicated its potential role in managing conditions such as Alzheimer's disease, neuropathic pain, and cancer. This review spotlights the health advantages of 1,8-cineole, as demonstrated in clinical trials involving patients with respiratory disorders, including chronic obstructive pulmonary disease, asthma, bronchitis, and rhinosinusitis. In addition, we shed light on potential therapeutic applications of 1,8-cineole in various conditions, such as depression, epilepsy, peptic ulcer disease, diarrhea, cardiac-related heart diseases, and diabetes mellitus. A comprehensive understanding of 1,8-cineole's pharmacodynamics and safety aspects as well as developing effective formulations, might help to leverage its therapeutic value. This thorough review sets the stage for future research on diverse health benefits and potential uses of 1,8-cineole in tackling complex medical conditions.

Sailing the Seven Seas: A Multinational Comparison of ChatGPT's Performance on Medical Licensing Examinations.

PURPOSE: The use of AI-powered technology, particularly OpenAI's ChatGPT, holds significant potential to reshape healthcare and medical education. Despite existing studies on the performance of ChatGPT in medical licensing examinations across different nations, a comprehensive, multinational analysis using rigorous methodology is currently lacking. Our study sought to address this gap by evaluating the performance of ChatGPT on six different national medical licensing exams and investigating the relationship between test question length and ChatGPT's accuracy. METHODS: We manually inputted a total of 1,800 test questions (300 each from US, Italian, French, Spanish, UK, and Indian medical licensing examination) into ChatGPT, and recorded the accuracy of its responses. RESULTS: We found significant variance in ChatGPT's test accuracy across different countries, with the highest accuracy seen in the Italian examination (73% correct answers) and the lowest in the French examination (22% correct answers). Interestingly, question length correlated with ChatGPT's performance in the Italian and French state examinations only. In addition, the study revealed that questions requiring multiple correct answers, as seen in the French examination, posed a greater challenge to ChatGPT. CONCLUSION: Our findings underscore the need for future research to further delineate ChatGPT's strengths and limitations in medical test-taking across additional countries and to develop guidelines to prevent AI-assisted cheating in medical examinations.

Novel Discovery of the Somatostatin Receptor (SSTR2) in Pleomorphic Adenomas via Immunohistochemical Analysis of Tumors of the Salivary Glands.

Reliable preoperative diagnosis between salivary gland tumor entities is difficult. In this monocentric retrospective study, we examined the somatostatin receptor 2 (SSTR2) status of salivary gland tumors after salivary gland tumor resection via immunohistochemistry (IHC), and stains were compared in analogy to the HER2 mamma scale. A total of 42.3% of all pleomorphic adenoma (PA) tumors (42 of 99, 95% confidence interval 32.5-52.8%) demonstrated ≥20% of cells displaying the SSTR2 as compared to just 1% of all other tumors (1/160, 95% CI 0.02-3.4%). The other tumor was a neuroendocrine carcinoma. PA had a higher intensity of SSTR2 staining, with 90.9% staining ≥ an intensity of 2 (moderate). Tumors with an intensity of SSTR2 expression equal to or greater than 2 had an 89.9% likelihood of being a PA (95% CI: 82.2-95.0%, AUC: 0.928). Only one Warthin tumor demonstrated a 'strong' SSTR2 staining intensity. No Warthin tumor showed a percentage of cells staining for SSTR2 above ≥20%. This result demonstrates consistent and strong expression of SSTR2 in PAs as compared to Warthin tumors, which may allow physicians to utilize radioligand-somatostatin analog PET CT/MR imaging to diagnose the PA. SSTR2 positivity, if shown to be clinically relevant, may allow peptide receptor radionuclide therapy in the future.

Liquid biopsy: an examination of platelet RNA obtained from head and neck squamous cell carcinoma patients for predictive molecular tumor markers.

Aim: Recently, a tumor cell-platelet interaction was identified in different tumor entities, resulting in a transfer of tumor-derived RNA into platelets, named further "tumor-educated platelets (TEP)". The present pilot study aims to investigate whether such a tumor-platelet transfer of RNA occurs also in patients suffering from head and neck squamous cell carcinoma (HNSCC). Methods: Sequencing analysis of RNA derived from platelets of tumor patients (TPs) and healthy donors (HDs) were performed. Subsequently, quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used for verification of differentially expressed genes in platelets from TPs and HDs in a second cohort of patients and HDs. Data were analyzed by applying bioinformatic tools. Results: Sequencing of RNA derived from the tumor as well as from platelets of TPs and HDs revealed 426 significantly differentially existing RNA, at which 406 RNA were more and 20 RNA less abundant in platelets from TPs in comparison to that of HDs. In TPs' platelets, abundantly existing RNA coding for 49 genes were detected, characteristically expressed in epithelial cells and RNA, the products of which are involved in tumor progression. Applying bioinformatic tools and verification on a second TP/HD cohort, collagen type I alpha 1 chain (COL1A1) and zinc finger protein 750 (ZNF750) were identified as the strongest potentially platelet-RNA-sequencing (RNA-seq)-based biomarkers for HNSCC. Conclusions: These results indicate a transfer of tumor-derived messenger RNA (mRNA) into platelets of HNSCC patients. Therefore, analyses of a patient's platelet RNA could be an efficient option for liquid biopsy in order to diagnose HNSCC or to monitor tumorigenesis as well as therapeutic responses at any time and in real time.

A distinct stimulatory cDC1 subpopulation amplifies CD8+ T cell responses in tumors for protective anti-cancer immunity.

Type 1 conventional dendritic cells (cDC1) can support T cell responses within tumors but whether this determines protective versus ineffective anti-cancer immunity is poorly understood. Here, we use imaging-based deep learning to identify intratumoral cDC1-CD8+ T cell clustering as a unique feature of protective anti-cancer immunity. These clusters form selectively in stromal tumor regions and constitute niches in which cDC1 activate TCF1+ stem-like CD8+ T cells. We identify a distinct population of immunostimulatory CCR7neg cDC1 that produce CXCL9 to promote cluster formation and cross-present tumor antigens within these niches, which is required for intratumoral CD8+ T cell differentiation and expansion and promotes cancer immune control. Similarly, in human cancers, CCR7neg cDC1 interact with CD8+ T cells in clusters and are associated with patient survival. Our findings reveal an intratumoral phase of the anti-cancer T cell response orchestrated by tumor-residing cDC1 that determines protective versus ineffective immunity and could be exploited for cancer therapy.

ChatGPT's quiz skills in different otolaryngology subspecialties: an analysis of 2576 single-choice and multiple-choice board certification preparation questions.

PURPOSE: With the increasing adoption of artificial intelligence (AI) in various domains, including healthcare, there is growing acceptance and interest in consulting AI models to provide medical information and advice. This study aimed to evaluate the accuracy of ChatGPT's responses to practice quiz questions designed for otolaryngology board certification and decipher potential performance disparities across different otolaryngology subspecialties. METHODS: A dataset covering 15 otolaryngology subspecialties was collected from an online learning platform funded by the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery, designed for board certification examination preparation. These questions were entered into ChatGPT, with its responses being analyzed for accuracy and variance in performance. RESULTS: The dataset included 2576 questions (479 multiple-choice and 2097 single-choice), of which 57% (n = 1475) were answered correctly by ChatGPT. An in-depth analysis of question style revealed that single-choice questions were associated with a significantly higher rate (p < 0.001) of correct responses (n = 1313; 63%) compared to multiple-choice questions (n = 162; 34%). Stratified by question categories, ChatGPT yielded the highest rate of correct responses (n = 151; 72%) in the field of allergology, whereas 7 out of 10 questions (n = 65; 71%) on legal otolaryngology aspects were answered incorrectly. CONCLUSION: The study reveals ChatGPT's potential as a supplementary tool for otolaryngology board certification preparation. However, its propensity for errors in certain otolaryngology areas calls for further refinement. Future research should address these limitations to improve ChatGPT's educational use. An approach, with expert collaboration, is recommended for the reliable and accurate integration of such AI models.

Unraveling the Role of Epithelial-Mesenchymal Transition in Adenoid Cystic Carcinoma of the Salivary Glands: A Comprehensive Review.

Salivary adenoid cystic carcinoma (SACC) is considered a challenging malignancy; it is characterized by a slow-growing nature, yet a high risk of recurrence and distant metastasis, presenting significant hurdles in its treatment and management. At present, there are no approved targeted agents available for the management of SACC and systemic chemotherapy protocols that have demonstrated efficacy remain to be elucidated. Epithelial-mesenchymal transition (EMT) is a complex process that is closely associated with tumor progression and metastasis, enabling epithelial cells to acquire mesenchymal properties, including increased mobility and invasiveness. Several molecular signaling pathways have been implicated in the regulation of EMT in SACC, and understanding these mechanisms is crucial to identifying new therapeutic targets and developing more effective treatment approaches. This manuscript aims to provide a comprehensive overview of the latest research on the role of EMT in SACC, including the molecular pathways and biomarkers involved in EMT regulation. By highlighting the most recent findings, this review offers insights into potential new therapeutic strategies that could improve the management of SACC patients, especially those with recurrent or metastatic disease.

Antibiotics Significantly Decrease the Survival of Head and Neck Carcinoma Patients with Immunotherapy: A Real-World Analysis of More Than 3000 Cases.

OBJECTIVE: The human gut microbiome is strongly influenced by the administration of drugs, namely antibiotics. We hypothesized that the effectiveness of immunotherapy with pembrolizumab in oral squamous cell carcinoma patients is decreased by the administration of antibiotics three months before and after immunotherapy. METHODS: We retrieved data from patients diagnosed with head and neck squamous cell carcinoma (HNSCC) (International Classification of Diseases [ICD]-10 codes C00-C14) and receiving immunotherapy with pembrolizumab from the TriNetX network. Two cohorts were built: patients in cohort I did not receive any antibiotics within three months before or up to three months after immunotherapy, while patients in cohort II were administered antibiotics at least once within three months before or after immunotherapy. To exclude confounders, we matched cohorts 1:1 for age, sex, secondary lymph node metastases, nicotine dependence, the insertion of feeding devices, body mass index (BMI) and severe sepsis. After defining the primary outcome as "death", a Kaplan-Meier analysis was performed, and the risk ratio (RR), odds ratio (OR) and hazard ratio (HR) were calculated. RESULTS: A total of 3651 patients were enrolled, and after matching, each cohort consisted of 1362 patients. Among cohorts I and II, 346 and 511 patients were deceased within one year (risk of death = 25.5 and 38.3%, respectively), whereby the risk difference was significant (p = 0.000; log-rank test). The RR was 0.68 (95% confidence interval: 0.60-0.76), OR was 0.57 (0.48-0.67) and HR was 0.58 (0.51-0.67). CONCLUSIONS: Our hypothesis was confirmed: administering antibiotics significantly decreases the drug effectiveness of immunotherapy. We hypothesize that this finding is associated with antibiotic-related changes in the gut microbiome. Prospective clinical studies on the gut microbiome in cancer patients are necessary to understand the complex ecosystem of microbiota during immunotherapy. TRIAL REGISTRATION: Due to the retrospective nature of the study, no registration was necessary.

Tumour budding-based grading as independent prognostic biomarker in HPV-positive and HPV-negative head and neck cancer.

BACKGROUND: The prognostic significance of tumour budding (TB) and minimal cell nest size (MCNS) was shown in human papillomavirus (HPV)-negative head and neck squamous cell carcinomas (HNSCC). However, the optimisation of cutpoints, the prognostic impact in HPV-positive HNSCC, and the comparison with other histopathological grading systems are insufficiently investigated. METHODS: TB and MCNS were analysed digitally in 1 and 10 high-power fields (HPF) of 331 HPV-positive and HPV-negative cases from TCGA. Optimising the cutpoints a new cellular dissociation grading (CDG) system was defined and compared to the WHO grading and the Brandwein-Gensler (BG) risk model. RESULTS: The two-tiered CDG system based solely on TB yielded optimal prognostic stratification with shortened overall survival for CDG-high cases. Optimal cut-offs were two buds (1 HPF) and six buds (10 HPF), respectively. Analysing MCNS did not add prognostic significance to quantifying TB. CDG was a significant prognostic marker in HPV-negative and HPV-positive tumours and prognostically superior to the WHO and BG systems. High CDG was associated with clinically occult lymph-node metastases. CONCLUSIONS: The most comprehensive study of TB in HNSCC so far confirmed its prognostic impact in HPV-negative tumours and for the first time in HPV-positive tumours. Further studies are warranted to evaluate its applicability for therapy guidance in HNSCC.

The profile of circulating extracellular vesicles depending on the age of the donor potentially drives the rejuvenation or senescence fate of hematopoietic stem cells.

Blood donor age has become a major concern due to the age-associated variations in the content and concentration of circulating extracellular nano-sized vesicles (EVs), including exosomes. These EVs mirror the state of their parental cells and transfer it to the recipient cells via biological messengers such as microRNAs (miRNAs, miRs). Since the behavior of hematopoietic stem cells (HSCs) is potentially affected by the miRs of plasma-derived EVs, a better understanding of the content of EVs is important for the safety and efficacy perspectives in blood transfusion medicine. Herein, we investigated whether the plasma-derived EVs of young (18-25 years) and elderly human donors (45-60 years) can deliver "youth" or "aging" signals into human umbilical cord blood (hUCB)-derived HSCs in vitro. The results showed that EVs altered the growth functionality and differentiation of HSCs depending on the age of the donor from which they are derived. EVs of young donors could ameliorate the proliferation and self-renewal potential of HSCs whereas those of aged donors induced senescence-associated differentiation in the target cells, particularly toward the myeloid lineage. These findings were confirmed by flow cytometric analysis of surface markers and microarray profiling of genes related to stemness (e.g., SOX-1, Nanog) and differentiation (e.g., PU-1). The results displayed an up-regulation of miR-29 and miR-96 and a down-regulation of miR-146 in EVs derived from elderly donors. The higher expression of miR-29 and miR-96 contributed to the diminished expression of CDK-6 and CDKN1A (p21), promoting senescence fate via cell growth suppression, while the lower expression of miR-146 positively regulates TRAF-6 expression to accelerate biological aging. Our findings reveal that plasma-derived EVs from young donors can reverse the aging-associated changes in HSCs, while vice versa, the EVs from elderly donors rather promote the senescence process.