HMGB1 Carried by Small Extracellular Vesicles Potentially Plays a Role in Promoting Acquired Middle Ear Cholesteatoma.

Cholesteatoma is a specific medical condition involving the abnormal, non-cancerous growth of skin-like tissue in the middle ear, potentially leading to a collection of debris and even infections. The receptor for advanced glycation (RAGE) and its ligand, high-mobility box 1 (HMGB1), are both known to be overexpressed in cholesteatoma and play a potential role in the pathogenesis of the disease. In this study, we investigated the role of small extracellular vesicles (sEVs) in carrying HMGB1 and inducing disease-promoting effects in cholesteatoma. No significant differences in the concentration of isolated sEVs in the plasma of cholesteatoma patients (n = 17) and controls (n = 22) were found (p > 0.05); however, cholesteatoma-derived sEVs carried significantly higher levels of HMGB1 (p < 0.05). In comparison to sEVs isolated from the plasma of controls, cholesteatoma-derived sEVs significantly enhanced keratinocyte proliferation and IL-6 production (p < 0.05), potentially by engaging multiple activation pathways including MAPKp44/p42, STAT3, and the NF-κB pathway. Thus, HMGB1(+) sEVs emerge as a novel factor potentially promoting cholesteatoma progression.

Hypoxia, but Not Normoxia, Reduces Effects of Resveratrol on Cisplatin Treatment in A2780 Ovarian Cancer Cells: A Challenge for Resveratrol Use in Anticancer Adjuvant Cisplatin Therapy.

Natural compounds, such as resveratrol (Res), are currently used as adjuvants for anticancer therapies. To evaluate the effectiveness of Res for the treatment of ovarian cancer (OC), we screened the response of various OC cell lines to the combined treatment with cisplatin (CisPt) and Res. We identified A2780 cells as the most synergistically responding, thus optimal for further analysis. Because hypoxia is the hallmark of the solid tumor microenvironment, we compared the effects of Res alone and in combination with CisPt in hypoxia (pO2 = 1%) vs. normoxia (pO2 = 19%). Hypoxia caused an increase (43.2 vs. 5.0%) in apoptosis and necrosis (14.2 vs. 2.5%), reactive oxygen species production, pro-angiogenic HIF-1α (hypoxia-inducible factor-1α) and VEGF (vascular endothelial growth factor), cell migration, and downregulated the expression of ZO1 (zonula occludens-1) protein in comparison to normoxia. Res was not cytotoxic under hypoxia in contrast to normoxia. In normoxia, Res alone or CisPt+Res caused apoptosis via caspase-3 cleavage and BAX, while in hypoxia, it reduced the accumulation of A2780 cells in the G2/M phase. CisPt+Res increased levels of vimentin under normoxia and upregulated SNAI1 expression under hypoxia. Thus, various effects of Res or CisPt+Res on A2780 cells observed in normoxia are eliminated or diminished in hypoxia. These findings indicate the limitations in using Res as an adjuvant with CisPt therapy in OC.

Small Extracellular Vesicles from Head and Neck Squamous Cell Carcinoma Cells Carry a Proteomic Signature for Tumor Hypoxia.

Tissue hypoxia is commonly observed in head and neck squamous cell carcinomas (HNSCCs), resulting in molecular and functional alterations of the tumor cells. The aim of this study was to characterize tumor-derived small extracellular vesicles (sEVs) released under hypoxic vs. normoxic conditions and analyze their proteomic content. HNSCC cells (FaDu, PCI-30, SCC-25) and HaCaT keratinocytes were cultured in 21, 10, 5, and 1% O2. sEVs were isolated from supernatants using size exclusion chromatography (SEC) and characterized by nanoparticle tracking analysis, electron microscopy, immunoblotting, and high-resolution mass spectrometry. Isolated sEVs ranged in size from 125-135 nm and contained CD63 and CD9 but not Grp94. sEVs reflected the hypoxic profile of HNSCC parent cells: about 15% of the total detected proteins were unique for hypoxic cells. Hypoxic sEVs expressed a common signature of seven hypoxia-related proteins (KT33B, DYSF, STON2, MLX, LIPA3, NEK5, P12L1) and were enriched in pro-angiogenic proteins. Protein profiles of sEVs reflected the degree of tumor hypoxia and could serve as potential sEV-based biomarkers for hypoxic conditions. Adaptation of HNSCC cells to hypoxia is associated with increased release of sEVs, which are enriched in a unique protein profile. Thus, tumor-derived sEVs can potentially be useful for evaluating levels of hypoxia in HNSCC.

Potential Roles of Tumor Cell- and Stroma Cell-Derived Small Extracellular Vesicles in Promoting a Pro-Angiogenic Tumor Microenvironment.

Extracellular vesicles (EVs) are produced and released by all cells and are present in all body fluids. They exist in a variety of sizes, however, small extracellular vesicles (sEVs), the EV subset with a size range from 30 to 150 nm, are of current interest. They are characterized by a distinct biogenesis and complex cargo composition, which reflects the cytosolic contents and cell-surface molecules of the parent cells. This cargo consists of proteins, nucleic acids, and lipids and is competent in inducing signaling cascades in recipient cells after surface interactions or in initiating the generation of a functional protein by delivering nucleic acids. Based on these characteristics, sEVs are now considered as important mediators of intercellular communication. One hallmark of sEVs is the promotion of angiogenesis. It was shown that sEVs interact with endothelial cells (ECs) and promote an angiogenic phenotype, ultimately leading to increased vascularization of solid tumors and disease progression. It was also shown that sEVs reprogram cells in the tumor microenvironment (TME) and act in a functionally cooperative fashion to promote angiogenesis by a paracrine mechanism involving the differential expression and secretion of angiogenic factors from other cell types. In this review, we will focus on the distinct functions of tumor-cell-derived sEVs (TEX) in promotion of angiogenesis and describe their potential as a therapeutic target for anti-angiogenic therapies. Also, we will focus on non-cancer stroma-cell-derived small extracellular vesicles and their potential role in stimulating a pro-angiogenic TME.

Ondine's Curse - Genetic and Iatrogenic Central Hypoventilation as Diagnostic Options in Forensic Medicine.

In the Nordic mythology a man lost his ability to breathe without remembering it after he was cursed by water nymph - referred to as 'Ondine's curse' - and then he died as soon as he fell asleep. Family medicine specialists are familiar with many sleeping disorders that their patients commonly call by the term Ondine's Curse. In medical sciences this term is historically related to the group of conditions that have as the common denominator seemingly spontaneous onset of life-threatening hypoventilation. The physiology and genetics specialists focus mainly on congenital central hypoventilation syndrome (CCHS), which was proven to be linked to several genetic mutations. Anesthesiologists tend to be more interested in similarly manifesting iatrogenic condition. Typically, patients that were previously subjected to general anesthesia, after temporarily waking up and regaining the spontaneous respiratory drive, later fall back into unconsciousness and develop hypoventilation. Anesthesiologists also call it Ondine's curse because of the sudden and unexpected sleep onset. The iatrogenic Ondine's curse is proven to be precipitated by delayed anesthetics release from patients' fat tissue - where it was deposited at the time general anesthesia was administered - back into bloodstream. Forensic medicine has to consider the latter form of Ondine's curse called scenario more often, as they investigate sudden deaths related to surgery and general anesthesia in the post-operational care period. These cases may also fall into the category of medical malpractice-related deaths.

Consent to eventual treatment in the intensive care unit expressed within the consent form for elective anaesthesia and surgery.

In contemporary clinical practice, the issue of requesting patient consent to perform therapeutic treatment plays an important role. The conscious consent of a patient as an expression of one's will greatly strengthens the legality of medical procedures performed by a physician, regardless of the medical field. However, obtaining consent to treatment in the intensive care unit (ICU) often poses enormous difficulties in daily clinical work, and has in recent decades been the cause of much dispute between doctors and lawyers. The correct interpretation of the provisions under the relevant laws determines the safety and comfort of the medical practice in the ICU. This study compared the current rules of normative acts of Polish common law relating to medical practice in intensive care units and issued on the basis of the judgments of the common court of law over the past ten years. On the basis of those provisions, the authors conclude that the patient should be informed by the anaesthesiologist during the visit as to the possibility of postoperative therapy in the ICU. The extent of such information depends on the likelihood of having treatment in the ICU. The consent of the patient for hospitalisation in the ICU should be mandatory in the case of treatments which are very likely to necessitate such hospitalisation. This concerns especially cardiac surgery, neurosurgery and treatments for patients with a significant burden of disease. The authors of this study propose that an information and consent form to undergo treatment in the intensive care unit should be included within the anaesthesia consent form.