Repeated sprint training in hypoxia induces specific skeletal muscle adaptations through S100A protein signaling.

Athletes increasingly engage in repeated sprint training consisting in repeated short all-out efforts interspersed by short recoveries. When performed in hypoxia (RSH), it may lead to greater training effects than in normoxia (RSN); however, the underlying molecular mechanisms remain unclear. This study aimed at elucidating the effects of RSH on skeletal muscle metabolic adaptations as compared to RSN. Sixteen healthy young men performed nine repeated sprint training sessions in either normoxia (FIO2 = 0.209, RSN, n = 7) or normobaric hypoxia (FIO2 = 0.136, RSH, n = 9). Before and after the training period, exercise performance was assessed by using repeated sprint ability (RSA) and Wingate tests. Vastus lateralis muscle biopsies were performed to investigate muscle metabolic adaptations using proteomics combined with western blot analysis. Similar improvements were observed in RSA and Wingate tests in both RSN and RSH groups. At the muscle level, RSN and RSH reduced oxidative phosphorylation protein content but triggered an increase in mitochondrial biogenesis proteins. Proteomics showed an increase in several S100A family proteins in the RSH group, among which S100A13 most strongly. We confirmed a significant increase in S100A13 protein by western blot in RSH, which was associated with increased Akt phosphorylation and its downstream targets regulating protein synthesis. Altogether our data indicate that RSH may activate an S100A/Akt pathway to trigger specific adaptations as compared to RSN.

Tetraspanin CD82 Correlates with and May Regulate S100A7 Expression in Oral Cancer.

Many metastatic cancers with poor prognoses correlate to downregulated CD82, but exceptions exist. Understanding the context of this correlation is essential to CD82 as a prognostic biomarker and therapeutic target. Oral squamous cell carcinoma (OSCC) constitutes over 90% of oral cancer. We aimed to uncover the function and mechanism of CD82 in OSCC. We investigated CD82 in human OSCC cell lines, tissues, and healthy controls using the CRISPR-Cas9 gene knockout, transcriptomics, proteomics, etc. CD82 expression is elevated in CAL 27 cells. Knockout CD82 altered over 300 genes and proteins and inhibited cell migration. Furthermore, CD82 expression correlates with S100 proteins in CAL 27, CD82KO, SCC-25, and S-G cells and some OSCC tissues. The 37-50 kDa CD82 protein in CAL 27 cells is upregulated, glycosylated, and truncated. CD82 correlates with S100 proteins and may regulate their expression and cell migration. The truncated CD82 explains the invasive metastasis and poor outcome of the CAL 27 donor. OSCC with upregulated truncated CD82 and S100A7 may represent a distinct subtype with a poor prognosis. Differing alternatives from wild-type CD82 may elucidate the contradictory functions and pave the way for CD82 as a prognostic biomarker and therapeutic target.

Malignant peripheral nerve sheath tumour with divergent epithelioid differentiation in a cat.

Divergent differentiation, mainly towards various subsets of mesenchymal cells, is encountered sporadically in human malignant peripheral nerve sheath tumours (MPNSTs) but this is the first report of epithelioid components within this neoplasm in a cat. An 8-year-old, spayed female Domestic Shorthaired cat was presented for surgical removal of a subcutaneous mass on the right flank. Morphological and immunohistochemical analysis revealed a malignant neoplasm with spindloid cells intermixed with an epithelioid component that had squamous differentiation. There was intense immunolabelling of vimentin, S100 protein, neuron-specific enolase, laminin and glial fibrillary acidic protein in the spindloid cell component and for cytokeratin (CK) AE1/AE3 and CK5/6 in the epithelial elements. Melanoma-associated antigen, desmin, α-smooth muscle actin, CD18, CD31, ionized calcium binding adapter molecule-1 and CK8/18 were not expressed, which helped differentiate the tumour from other feline spindloid cell neoplasms. These features are characteristic of divergent epithelioid differentiation of MPNST.

S100Z is expressed in a lateral subpopulation of olfactory receptor neurons in the main olfactory system of Xenopus laevis.

In contrast to other S100 protein members, the function of S100 calcium-binding protein Z (S100Z) remains largely uncharacterized. It is expressed in the olfactory epithelium of fish, and it is closely associated with the vomeronasal organ (VNO) in mammals. In this study, we analyzed the expression pattern of S100Z in the olfactory system of the anuran amphibian Xenopus laevis. Using immunohistochemistry in whole mount and slice preparations of the larval olfactory system, we found exclusive S100Z expression in a subpopulation of olfactory receptor neurons (ORNs) of the main olfactory epithelium (MOE). S100Z expression was not co-localized with TP63 and cytokeratin type II, ruling out basal cell and supporting cell identity. The distribution of S100Z-expressing ORNs was laterally biased, and their average number was significantly increased in the lateral half of the olfactory epithelium. The axons of S100Z-positive neurons projected exclusively into the lateral and intermediate glomerular clusters of the main olfactory bulb (OB). Even after metamorphic restructuring of the olfactory system, S100Z expression was restricted to a neuronal subpopulation of the MOE, which was then located in the newly formed middle cavity. An axonal projection into the ventro-lateral OB persisted also in postmetamorphic frogs. In summary, S100Z is exclusively associated with the main olfactory system in the amphibian Xenopus and not with the VNO as in mammals, despite the presence of a separate accessory olfactory system in both classes.

Recognition of granulocyte-macrophage colony-stimulating factor by specific S100 proteins.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a pleiotropic myelopoietic growth factor and proinflammatory cytokine, clinically used for multiple indications and serving as a promising target for treatment of many disorders, including cancer, multiple sclerosis, rheumatoid arthritis, psoriasis, asthma, COVID-19. We have previously shown that dimeric Ca2+-bound forms of S100A6 and S100P proteins, members of the multifunctional S100 protein family, are specific to GM-CSF. To probe selectivity of these interactions, the affinity of recombinant human GM-CSF to dimeric Ca2+-loaded forms of 18 recombinant human S100 proteins was studied by surface plasmon resonance spectroscopy. Of them, only S100A4 protein specifically binds to GM-CSF with equilibrium dissociation constant, Kd, values of 0.3-2 µM, as confirmed by intrinsic fluorescence and chemical crosslinking data. Calcium removal prevents S100A4 binding to GM-CSF, whereas monomerization of S100A4/A6/P proteins disrupts S100A4/A6 interaction with GM-CSF and induces a slight decrease in S100P affinity for GM-CSF. Structural modelling indicates the presence in the GM-CSF molecule of a conserved S100A4/A6/P-binding site, consisting of the residues from its termini, helices I and III, some of which are involved in the interaction with GM-CSF receptors. The predicted involvement of the 'hinge' region and F89 residue of S100P in GM-CSF recognition was confirmed by mutagenesis. Examination of S100A4/A6/P ability to affect GM-CSF signaling showed that S100A4/A6 inhibit GM-CSF-induced suppression of viability of monocytic THP-1 cells. The ability of the S100 proteins to modulate GM-CSF activity is relevant to progression of various neoplasms and other diseases, according to bioinformatics analysis. The direct regulation of GM-CSF signaling by extracellular forms of the S100 proteins should be taken into account in the clinical use of GM-CSF and development of the therapeutic interventions targeting GM-CSF or its receptors.

Study on the mechanism of S100A4-mediated cancer oncogenesis in uveal melanoma cells through the integration of bioinformatics and in vitro experiments.

BACKGROUND: The elevated metastasis rate of uveal melanoma (UM) is intricately correlated with patient prognosis, significantly affecting the quality of life. S100 calcium-binding protein A4 (S100A4) has tumorigenic properties; therefore, the present study investigated the impact of S100A4 on UM cell proliferation, apoptosis, migration, and invasion using bioinformatics and in vitro experiments. METHODS: Bioinformatic analysis was used to screen S100A4 as a hub gene and predict its possible mechanism in UM cells, and the S100A4 silencing cell line was constructed. The impact of S100A4 silencing on the proliferative ability of UM cells was detected using the Cell Counting Kit-8 and colony formation assays. Annexin V-FITC/PI double fluorescence and Hoechst 33342 staining were used to observe the effects of apoptosis on UM cells. The effect of S100A4 silencing on the migratory and invasive capabilities of UM cells was assessed using wound healing and Transwell assays. Western blotting was used to detect the expression of related proteins. RESULTS: The present study found that S100A4 is a biomarker of UM, and its high expression is related to poor prognosis. After constructing the S100A4 silencing cell line, cell viability, clone number, proliferating cell nuclear antigen, X-linked inhibitor of apoptosis protein, and survivin expression were decreased in UM cells. The cell apoptosis rate and relative fluorescence intensity increased, accompanied by increased levels of Bax and caspase-3 and decreased levels of Bcl-2. Additionally, a decrease in the cell migration index and relative invasion rate was observed with increased E-cadherin expression and decreased N-cadherin and vimentin protein expression. CONCLUSION: S100A4 silencing can inhibit the proliferation, migration, and invasion and synchronously induces apoptosis in UM cells.

Calcium mediated static and dynamic allostery in S100A12: Implications for target recognition by S100 proteins.

Structure and functions of S100 proteins are regulated by two distinct calcium binding EF hand motifs. In this work, we used solution-state NMR spectroscopy to investigate the cooperativity between the two calcium binding sites and map the allosteric changes at the target binding site. To parse the contribution of the individual calcium binding events, variants of S100A12 were designed to selectively bind calcium to either the EF-I (N63A) or EF-II (E31A) loop, respectively. Detailed analysis of the backbone chemical shifts for wildtype protein and its mutants indicates that calcium binding to the canonical EF-II loop is the principal trigger for the conformational switch between 'closed' apo to the 'open' Ca2+ -bound conformation of the protein. Elimination of binding in S100-specific EF-I loop has limited impact on the calcium binding affinity of the EF-II loop and the concomitant structural rearrangement. In contrast, deletion of binding in the EF-II loop significantly attenuates calcium affinity in the EF-I loop and the structure adopts a 'closed' apo-like conformation. Analysis of experimental amide nitrogen (15 N) relaxation rates (R1 , R2 , and 15 N-{1 H} NOE) and molecular dynamics (MD) simulations demonstrate that the calcium bound state is relatively floppy with pico-nanosecond motions induced in functionally relevant domains responsible for target recognition such as the hinge domain and the C-terminal residues. Experimental relaxation studies combined with MD simulations show that while calcium binding in the EF-I loop alone does not induce significant motions in the polypeptide chain, EF-I regulates fluctuations in the polypeptide in the presence of bound calcium in the EF-II loop. These results offer novel insights into the dynamic regulation of target recognition by calcium binding and unravels the role of cooperativity between the two calcium binding events in S100A12.

Tumor neuroectodérmico maligno del tracto gastrointestinal: a propósito de un caso / Malignant neuroectodermal tumor of the gastrointestinal tract: case report

El tumor neuroectodérmico maligno del tracto gastrointestinal es una neoplasia rara con pocos casos reportados en la literatura, especialmente en América Latina. Descrito por primera vez en 2003, se trata de una entidad sin tratamiento estandarizado y de pobre pronóstico. Se presenta el caso de una paciente de 22 años de edad que acude a la consulta por dolor abdominal, anemia y masa abdominal palpable. Luego de estudios pertinentes se decide la conducta resectiva y el posterior tratamiento oncológico. (AU)

Malignant gastrointestinal neuroectodermal tumor (GNET), formerly known as clear cell sarcoma of the gastrointestinal tract, is an extremely rare tumor of mesenchymal origin, which presents great microscopic and molecular similarity to clear cell sarcoma found in other parts of the body, such as tendons and aponeurosis. It is characterized by its rapid evolution, high recurrence rate and frequent diagnosis as metastatic disease.1,2 (AU)

Modulation of prostaglandin transport activity of SLCO2A1 by annexin A2 and S100A10.

Solute carrier organic anion transporter family member 2A1 (SLCO2A1) is a prostaglandin (PG) transporter and serves as the osmosensitive ATP-permeable maxi-anion channel (Maxi-Cl). Since a heterotetrameric complex of annexin A2 (ANXA2) and S100A10 is obligatory for the channel activity, the present study aimed to determine if they regulate SLCO2A1-mediated PG transport. This study examined PGE2 uptake and ATP release in Anxa2 and/or S100a10 knockout (KO) murine breast C127 cells. Deletion of Slco2a1 decreased PGE2-d4 uptake by wild-type (WT) cells in an isotonic medium (290 mosmol/kgH2O). Decreased osmolarity (135 mosmol/kgH2O) stimulated ATP release but did not affect PGE2 uptake kinetics, showing Km (1,280 nM) and Vmax (10.38 pmol/15 s/mg protein) similar to those in isotonic medium (1,227 nM and 10.65 pmol/15 s/mg protein), respectively, in WT cells. Deletion of Anxa2 associated with loss of S100a10 diminished SLCO2A1-mediated ATP release and uncompetitively inhibited PGE2 uptake with lowered Km (376 nM) and Vmax (2.59 pmol/15 s/mg protein). Moreover, the immunoprecipitation assay confirmed the physical interaction of ANXA2 with SLCO2A1 in WT cells. Enforcement of ANXA2 expression to Anxa2 KO cells partially restored PGE2 uptake and increased Km (744.3 nM) and Vmax (9.07 pmol/15 s/mg protein), whereas the uptake clearance (Vmax/Km) did not change much regardless of ANXA2 expression. These results suggest that an ANXA2/S100A10 complex modulates PG transport activity but osmolality has little effect on it; therefore, the bound form of SLCO2A1, which functions as a PG transporter and Maxi-Cl, may exist regardless of changes in the cell volume.NEW & NOTEWORTHY A previous study indicated that the ANXA2/S100A10 complex represents the regulatory component of SLCO2A1-mediated Maxi-Cl channel activity. The present study showed that apparent PGE2 uptake by C127 cells was osmoinsensitive and uncompetitively inhibited by loss of ANXA2 expression, demonstrating that ANXA2 is a regulatory factor of SLCO2A1-mediated PG transport activity.

Extracellular-vesicle-packaged S100A11 from osteosarcoma cells mediates lung premetastatic niche formation by recruiting gMDSCs.

The premetastatic niche (PMN) contributes to lung-specific metastatic tropism in osteosarcoma. However, the crosstalk between primary tumor cells and lung stromal cells is not clearly defined. Here, we dissect the composition of immune cells in the lung PMN and identify granulocytic myeloid-derived suppressor cell (gMDSC) infiltration as positively associated with immunosuppressive PMN formation and tumor cell colonization. Osteosarcoma-cell-derived extracellular vesicles (EVs) activate lung interstitial macrophages to initiate the influx of gMDSCs via secretion of the chemokine CXCL2. Proteomic profiling of EVs reveals that EV-packaged S100A11 stimulates the Janus kinase 2/signal transducer and activator of transcription 3 signaling pathway in macrophages by interacting with USP9X. High level of S100A11 expression or circulating gMDSCs correlates with the presentation of lung metastasis and poor prognosis in osteosarcoma patients. In summary, we identify a key role of tumor-derived EVs in lung PMN formation, providing potential strategies for monitoring or preventing lung metastasis in osteosarcoma.

FLIM-FRET-based analysis of S100A11/annexin interactions in living cells.

Proteins achieve their biological functions in cells by cooperation in protein complexes. In this study, we employed fluorescence lifetime imaging microscopy (FLIM)-based Förster resonance energy transfer (FRET) measurements to investigate protein complexes comprising S100A11 and different members of the annexin (ANX) family, such as ANXA1, ANXA2, ANXA4, ANXA5, and AnxA6, in living cells. Using an S100A11 mutant without the capacity for Ca2+ binding, we found that Ca2+ binding of S100A11 is important for distinct S100A11/ANXA2 complex formation; however, ANXA1-containing complexes were unaffected by this mutant. An increase in the intracellular calcium concentration induced calcium ionophores, which strengthened the ANXA2/S100A11 interaction. Furthermore, we were able to show that S100A11 also interacts with ANXA4 in living cells. The FLIM-FRET approach used here can serve as a tool to analyze interactions between S100A11 and distinct annexins under physiological conditions in living cells.

On-Site Melanoma Diagnosis Utilizing a Swellable Microneedle-Assisted Skin Interstitial Fluid Sampling and a Microfluidic Particle Dam for Visual Quantification of S100A1.

Malignant melanoma (MM) is the most aggressive form of skin cancer. The delay in treatment will induce metastasis, resulting in a poor prognosis and even death. Here, a two-step strategy for on-site diagnosis of MM is developed based on the extraction and direct visual quantification of S100A1, a biomarker for melanoma. First, a swellable microneedle is utilized to extract S100A1 in skin interstitial fluid (ISF) with minimal invasion. After elution, antibody-conjugated magnetic microparticles (MMPs) and polystyrene microparticles (PMPs) are introduced. A high expression level of S100A1 gives rise to a robust binding between MMPs and PMPs and reduces the number of free PMPs. By loading the reacted solution into the device with a microfluidic particle dam, the quantity of free PMPs after magnetic separation is displayed with their accumulation length inversely proportional to S100A1 levels. A limit of detection of 18.7 ng mL-1 for S100A1 is achieved. The animal experiment indicates that ISF-based S100A1 quantification using the proposed strategy exhibits a significantly higher sensitivity compared with conventional serum-based detection. In addition, the result is highly comparable with the gold standard enzyme-linked immunosorbent assay based on Lin's concordance correlation coefficient, suggesting the high practicality for routine monitoring of melanoma.

Intramuscular Hybrid Nerve Sheath Tumor of the Thigh: Case Report and Literature Review.

BACKGROUND/AIM: Hybrid nerve sheath tumor (HNST) is a benign peripheral nerve sheath tumor with combined features of more than one histological type, such as schwannoma, neurofibroma, and perineurioma. It remains under-recognized in routine clinical practice. Herein, we describe an unusual case of intramuscular HNST of the thigh. CASE REPORT: The patient was a 41-year-old man with no history of trauma who presented with a 3-month history of a palpable mass in the right thigh. Physical examination revealed a 4-cm, elastic hard, mobile, nontender mass. Magnetic resonance imaging exhibited a well-circumscribed intramuscular mass with low-to-intermediate signal intensity on T1-weighted sequences and higher signal intensity peripherally and lower signal intensity centrally, representing a target sign, on T2-weighted sequences. Complete surgical excision of the tumor was carried out. Microscopically, the tumor showed dual histological components of both schwannoma and neurofibroma. Immunohistochemically, the schwannomatous component was strongly and diffusely positive for S-100 protein and negative for CD34, while the neurofibromatous component contained CD34-positive fibroblasts and S-100 protein-positive Schwann cells. Epithelial membrane antigen was negative for both components. These findings were consistent with a diagnosis of HNST (hybrid schwannoma/neurofibroma). The patient had no evidence of local recurrence and no neurological deficit at the final follow-up. CONCLUSION: Although extremely rare, HNST should be included in the extended differential diagnosis of a well-circumscribed, intramuscular soft-tissue mass in the extremities, particularly in young and early middle-aged adults.

Myoid gonadal stromal tumor of the testis-the novel subtype of testicular gonadal stromal tumors: a case report and review of the literature.

BACKGROUND: Sex cord gonadal stromal tumors compose less than 10% of all testicular neoplasms and consist of a variety of histological subtypes. In 2016, the World Health Organization introduced a novel subtype, the myoid gonadal stromal tumor, that consists of spindle-shaped cells with immunohistologic features of muscle cells. Only few cases have been reported to date. Due to its rarity and owing to its only recent introduction, the current knowledge about myoid gonadal stromal tumor is limited, and particularly, appropriate clinical management is still ill-defined. CASE PRESENTATION: A 47-year-old man of Caucasian descent presented with nonspecific scrotal discomfort. A roundish and well demarcated hypoechoic mass of 8.5 mm in diameter was detected in the cranial region of the left testis. Serum tumor marker levels were within normal ranges. Testis-sparing surgery revealed a 9-mm whitish, hard mass with sharp surgical margin. Histologically, the neoplasm consisted of microfibrillar tissue with spindle-shaped cells harboring elongated nuclei. Immunohistochemical work-up disclosed expression of desmin, small muscle actin, and S100 protein giving evidence for the myogenic nature of the neoplastic cells. There was no indication of malignancy, neither histologically nor clinically. Follow-up of 1 year was uneventful. CONCLUSION: A literature survey revealed 22 previous cases of myoid gonadal stromal tumor. The median age was 37 years, the median size of the neoplasm was 20 mm, and there was no side-preponderance. Myoid gonadal stromal tumor is not much different from other subtypes of gonadal stromal tumors nor from testicular gem cell tumors regarding age and laterality; however, tumor size is smaller in myoid gonadal stromal tumors than in germ cell tumors. Although rarely performed so far, testis-sparing surgery probably constitutes an appropriate treatment of this neoplasm. Myoid gonadal stromal tumor represents an emerging novel entity of benign testicular new growths that caregivers of patients with testicular tumors should be aware of.

Malignant peripheral nerve sheath tumor in the kidney of a dog.

A 12-year-old castrated male poodle presented with vomiting and diarrhea. Ultrasonography and computed tomography revealed a protruding mass at the caudal pole of the left kidney. Grossly, the poorly circumscribed abnormal mass was 1.6 × 1.8 × 1.9 cm in size and had multifocal dark-red foci. Microscopically, it was composed of densely or loosely packed variable-sized short spindle or ovoid cells. These neoplastic cells showed high pleomorphism, mitotic figures, and invasive tendency to the adjacent tissue. Immunohistochemically, the neoplastic spindle cells expressed vimentin, S100, neuron-specific enolase, nerve growth factor receptor, and laminin. Therefore, the mass was diagnosed as a malignant peripheral nerve sheath tumor (MPNST). To our knowledge, this is the first report of primary renal MPNST in a dog.

S100A11 promotes focal adhesion disassembly via myosin II-driven contractility and Piezo1-mediated Ca2+ entry.

S100A11 is a small Ca2+-activatable protein known to localize along stress fibers (SFs). Analyzing S100A11 localization in HeLa and U2OS cells further revealed S100A11 enrichment at focal adhesions (FAs). Strikingly, S100A11 levels at FAs increased sharply, yet transiently, just before FA disassembly. Elevating intracellular Ca2+ levels with ionomycin stimulated both S100A11 recruitment and subsequent FA disassembly. However, pre-incubation with the non-muscle myosin II (NMII) inhibitor blebbistatin or with an inhibitor of the stretch-activatable Ca2+ channel Piezo1 suppressed S100A11 recruitment, implicating S100A11 in an actomyosin-driven FA recruitment mechanism involving Piezo1-dependent Ca2+ influx. Applying external forces on peripheral FAs likewise recruited S100A11 to FAs even if NMII activity was inhibited, corroborating the mechanosensitive recruitment mechanism of S100A11. However, extracellular Ca2+ and Piezo1 function were indispensable, indicating that NMII contraction forces act upstream of Piezo1-mediated Ca2+ influx, in turn leading to S100A11 activation and FA recruitment. S100A11-knockout cells display enlarged FAs and had delayed FA disassembly during cell membrane retraction, consistent with impaired FA turnover in these cells. Our results thus demonstrate a novel function for S100A11 in promoting actomyosin contractility-driven FA disassembly.

Downregulation of S100A11 promotes T cell infiltration by regulating cancer-associated fibroblasts in prostate cancer.

OBJECTIVE: This study aims at revealing the relationship between S100A11 and cancer-associated fibroblasts (CAFs) in prostate cancer and improving T cell infiltration into solid tumors. METHODS: H&E, IHC and Sirius red staining were used to detect the stroma content in prostate cancer tissues. Stable S100A11 knockdown cell lines DU 145, 22Rv1, RM-1 and NOR-10 were established by lentivirus transfection. Co-culture system of RM-1 and CAFs was established. CCK-8, wound healing and transwell were proceeded to determine proliferation, migration and invasion of prostate cancer cells. Stably knocked-down RM-1 and CAFs were co-injected into C57BL/6 mice to detect the role of S100A11 in vivo. CAFs, CD4+ T cell and CD8+ T cell in these tumors were assessed by IF. T cell profile was analyzed by flow cytometry. RESULTS: A significant amount of stroma exists in prostate cancer tissues. Downregulation of S100A11 inhibits proliferation, migration and invasion of human prostate cancer cells in vitro, and suppresses the expression of cancer-associated fibroblasts (CAFs) in vivo. Knockdown of S100A11 enhances the inhibitory effect of Erdafitinib on CAFs in both the co-culture system and in vivo. The combined knockdown of S100A11 in tumor cells and CAFs shows a superior therapeutic effect compared to the individual knockdown in tumor cells alone. Knockdown of S100A11, both in RM-1 and CAFs, combined with Erdafitinib treatment reduces tumorigenicity by suppressing the content of CAFs and increasing the infiltration of CD4+ T cell and effective CD8+ T cell in tumor. CONCLUSION: Downregulation of S100A11 plays a crucial role in enhancing the therapeutic response to Erdafitinib and reversing immunosuppressive tumor microenvironment.

Sarcomas Harboring EWSR1::PATZ1 Fusions: A Clinicopathologic Study of 17 Cases.

Soft tissue sarcomas harboring EWSR1::PATZ1 are a recently recognized entity with variable morphology and a heterogeneous immunohistochemical profile. We studied 17 such tumors. The tumors occurred in 12 men and 5 women (median age, 50 years; range, 15-71 years), involved the thoracoabdominal soft tissues (14 cases; 82%), lower extremities (2 cases; 12%), and tongue (1 case; 6%), and ranged from 0.7 to 11.3 cm (median, 4.7 cm). All but 1 patient received complete surgical resection; 7 were also treated with neoadjuvant chemo/radiotherapy. All cases showed typical features of EWSR1::PATZ1 sarcoma, including uniform round to spindled cells, fibromyxoid matrix, fibrous bands, hyalinized vessels, and pseudoalveolar/microcystic spaces. Unusual features, seen in a subset of cases, included degenerative-appearing nuclear atypia, epithelioid cytomorphology, mature fat, abundant rhabdomyoblasts, high mitotic activity, and foci with increased cellularity and nuclear atypia. Positive immunohistochemical results were desmin (16/17, 94%), MyoD1 (13/14, 93%), myogenin (6/14, 43%), GFAP (10/10, 100%), S100 protein (15/17, 88%), SOX10 (7/13, 54%), keratin (10/17, 59%), CD99 (4/11, 36%), H3K27me3 (retained expression 9/9, 100%), p16 (absent expression 1/4, 25%), and p53 (wild type 3/3, 100%). Fusion events included EWSR1 exon 8::PATZ1 exon 1 (14/17, 82%), EWSR1 exon 9::PATZ1 exon 1 (2/17, 12%), and EWSR1 exon 7::PATZ1 exon 1 (1/17, 6%). No evaluated tumor had alterations of CDKN2A/B and/or TP53, or MDM2 amplification. Clinical follow-up (16 patients: median, 13.5 months; range, 1-77 months) showed distant metastases in 3 patients (1/3 at time of presentation) and no local recurrences. At the time of last follow-up, 14 patients were disease free, 1 was alive with disease, 1 was dead of disease (at 13 months), and 1 had an indeterminant pulmonary nodule. We conclude that the morphologic spectrum of EWSR1::PATZ1 is broader than has been previously appreciated. Although more long-term follow-up is needed, the prognosis of these very rare sarcomas may be more favorable than previously reported.

Temporospatial dynamics of the morphogenesis of the rabbit retina from prenatal to postnatal life: Light and electron microscopic study.

The retina consists of various cell types arranged in eight cell layers and two membranes that originate from the neuroectodermal cells. In this study, the timing of differentiation and distribution of the cellular components and the layers of the rabbit retina are investigated using light and electron microscopy and immunohistochemical techniques. There were 32 rabbit embryos and 12 rabbits used. The rabbit retina begins its prenatal development on the 10th day of gestation in the form of optic cup. The process of neuro- and gliogenesis occurs in several stages: In the first stage, the ganglionic cells are differentiated at the 15th day. The second stage includes the differentiation of Muller, amacrine, and cone cells on the 23rd day. The differentiation of bipolar, horizontal, and rod cells and formation of the inner segments of the photoreceptors consider the late stage that occurs by the 27th and 30th day of gestation. On the first week of age postnatally, the outer segments of the photoreceptors are developed. S100 protein is expressed by the Muller cells and its processes that traverse the retina from the outer to the inner limiting membranes. Calretinin is intensely labeled within the amacrine and displaced amacrine cells. Ganglionic cells exhibited moderate immunoreactivity for calretinin confined to their cytoplasm and dendrites. In conclusion, all stages of neuro- and gliogenesis of the rabbit retina occur during the embryonic period. Then, the retina continues its development postnatally by formation of the photoreceptor outer segments and all layers of the retina become established. RESEARCH HIGHLIGHTS: The aim of this study is to investigate the morphogenesis of the rabbit retina during pre- and postnatal life. The primordia of the retina could be observed in the form of the optic cup. The ganglionic cells are the first cells to differentiate, while the photoreceptor cells are the last. S100 protein is expressed by the Muller cells and its processes. Calretinin is intensely labeled in the amacrine and displaced amacrine cells and moderately expressed in the cytoplasm and dendrites of ganglionic cells.

Cardiac tumor comprising a malignant peripheral nerve sheath tumor and spontaneous atrial osseous metaplasia in a sheep.

Primary cardiac tumors in animals are very rare. The purpose of this report was to describe the first case of a cardiac tumor comprising a malignant peripheral nerve sheath tumor and spontaneous atrial osseous metaplasia in a Corriedale sheep. Histologically, the tumor in the bilateral atrial pericardium consisted of dense cellular components comprising tumor cells and a sparse cellular area, and non-neoplastic mature bone tissue. The tumor cells were spindle-shaped, round, or polygonal, and proliferating, with fascicular, storiform, palisading, and sheet patterns. Immunohistochemically, the tumor cells were positive for vimentin, S-100, occasionally positive for myeline basic protein, glial fibrillary acidic protein, neurofilament, neuron specific enolase, and neuron growth factor receptor suggesting that they originated from the nervous system. On the basis of these findings, the final diagnosis was a malignant peripheral nerve sheath tumor and spontaneous atrial osseous metaplasia.