Composite haemangioendothelioma with neuroendocrine marker differentiation presenting as a pink-brown nodule.

We report a case of a 55-year-old female with an asymptomatic pink-brown nodule. Histological examination demonstrated a composite haemangioendothelioma with positive synaptophysin staining.

Cognition, function, and prevalent dementia in centenarians and near-centenarians: An individual participant data (IPD) meta-analysis of 18 studies.

INTRODUCTION: There are limited data on prevalence of dementia in centenarians and near-centenarians (C/NC), its determinants, and whether the risk of dementia continues to rise beyond 100. METHODS: Participant-level data were obtained from 18 community-based studies (N = 4427) in 11 countries that included individuals ≥95 years. A harmonization protocol was applied to cognitive and functional impairments, and a meta-analysis was performed. RESULTS: The mean age was 98.3 years (SD = 2.67); 79% were women. After adjusting for age, sex, and education, dementia prevalence was 53.2% in women and 45.5% in men, with risk continuing to increase with age. Education (OR 0.95;0.92-0.98) was protective, as was hypertension (odds ratio [OR] 0.51;0.35-0.74) in five studies. Dementia was not associated with diabetes, vision and hearing impairments, smoking, and body mass index (BMI). DISCUSSION: Among the exceptional old, dementia prevalence remains higher in the older participants. Education was protective against dementia, but other factors for dementia-free survival in C/NC remain to be understood.

HyClear: A Novel Tissue Clearing Solution for One-Step Clearing of Microtissues.

3-D cell cultures are being increasingly used as in vitro models are capable of better mimicry of in vivo tissues, particularly in drug screenings where mass transfer limitations can affect the cancer biology and response to drugs. Three-dimensional microscopy techniques, such as confocal and multiphoton microscopy, have been used to elucidate data from 3-D cell cultures and whole organs, but their reach inside the 3-D tissues is restrained by the light scattering of the tissues, limiting their effective reach to 100-200 µm, which is simply not enough. Tissue clearing protocols, developed mostly for larger specimens usually involve multiple steps of viscous liquid submersion, and are not easily adaptable for much smaller spheroids and organoids. In this work, we have developed a novel tissue clearing solution tailored for small spheroids and organoids. Our tissue clearing protocol, called HyClear, uses a mixture of DMSO, HPG and urea to allow for one-step tissue clearing of spheroids and organoids, and is compatible with high-throughput screening studies due to its speed and simplicity. We have shown that our tissue clearing agent is superior to many of the commonly used tissue clearing agents and allows for elucidating better quality data from drug screening experiments.

Multiple eruptive squamoproliferative lesions during anti-PD1 immunotherapy for metastatic melanoma: Pathogenesis, immunohistochemical analysis and treatment.

Treatment with anti-PD1 inhibitors may enhance the risk for developing low grade squamoproliferative skin tumors. Immunohistochemical (IHC) analysis of the immune tumor microenvironment (TME) allows exploration of the pathogenesis and relationship with the PD1/PDL1 axis. Patients with eruptive keratoacanthoma (KA)-like lesions were recruited from the Melanoma Institute Australia, a tertiary referral specialist melanoma treatment center from January 2015 to August 2017. Clinicopathologic evaluation and IHC features of tumor cells (PDL1 expression) and peritumoral microenvironment (PD1, FOXP3, PDL1, CD4:CD8 expressing cells) in 12 eruptive KA-like lesions, were compared with solitary KAs in age and sex matched non-anti-PD1 treated controls. Four patients with repeated episodes of eruptive KA-like and lichenoid lesions developing 2-7 months after commencing pembrolizumab for AJCC stage IV melanoma, were recruited. Eruptive KA-like squamoproliferative lesions occurred in sun exposed sites and in areas of resolving, concomitant or delayed lichenoid reactions. Histologically, the lesions were well-differentiated squamoproliferative lesions resembling infundibulocystic squamous cell carcinoma or KA. IHC of cases and controls revealed low PDL1 expression of both squamous tumor cells and the TME immune cells. The numbers of immunosuppressive FOXP3 positive Tregs and PD1-expressing T-cells were higher in the cases than the controls but the CD4:CD8 ratio (2:1) was similar. The patients best responded to acitretin and were managed surgically if they demonstrated neoplastic features. Accelerated squamoproliferative growth in actinically damaged keratinocytes associated with lichenoid eruptions may be unmasked in patients treated with anti-PD1 immunotherapy potentially contributed to by a local cutaneous immunosuppressed TME.

Airway-On-A-Chip: Designs and Applications for Lung Repair and Disease.

The lungs are affected by illnesses including asthma, chronic obstructive pulmonary disease, and infections such as influenza and SARS-CoV-2. Physiologically relevant models for respiratory conditions will be essential for new drug development. The composition and structure of the lung extracellular matrix (ECM) plays a major role in the function of the lung tissue and cells. Lung-on-chip models have been developed to address some of the limitations of current two-dimensional in vitro models. In this review, we describe various ECM substitutes utilized for modeling the respiratory system. We explore the application of lung-on-chip models to the study of cigarette smoke and electronic cigarette vapor. We discuss the challenges and opportunities related to model characterization with an emphasis on in situ characterization methods, both established and emerging. We discuss how further advancements in the field, through the incorporation of interstitial cells and ECM, have the potential to provide an effective tool for interrogating lung biology and disease, especially the mechanisms that involve the interstitial elements.

A case report of temple squamoid eccrine ductal carcinoma: A diagnostic challenge beneath the tip of the iceberg.

Eccrine carcinomas are a rare tumor entity which originates from eccrine glands and comprise <0.01% of all cutaneous tumors. Eccrine carcinoma subtypes are classified based on their distinct histopathological pattern. Squamoid eccrine ductal carcinoma (SEDC) is a rare subtype, characterized by both squamous and adnexal ductal differentiation, and resembles squamous cell carcinoma on clinical examination. Given the rarity of these tumors, there remains a lack of clear diagnostic criteria or treatment guidelines for the management of SEDC. We report a rare case of SEDC with perineural invasion in an elderly gentleman who was treated with wide local excision.

Long-term monitoring in a microfluidic system to study tumour spheroid response to chronic and cycling hypoxia.

We demonstrate the application of a microfluidic platform combining spatiotemporal oxygen control and long-term microscopy monitoring to observe tumour spheroid response to hypoxia. The platform is capable of recreating physiologically-relevant low and cycling oxygen levels not attainable in traditional cell culture environments, while image-based monitoring visualizes cell response to these physiologically-relevant conditions. Monitoring spheroid cultures during hypoxic exposure allows us to observe, for the first time, that spheroids swell and shrink in response to time-varying oxygen profiles switching between 0% and 10% O2; this swelling-shrinkage behaviour appears to be driven by swelling of individual cells within the spheroids. We also apply the system to monitoring tumour models during anticancer treatment under varying oxygen conditions. We observe higher uptake of the anticancer agent doxorubicin under a cycling hypoxia profile than under either chronic hypoxia or in vitro normoxia, and the two-photon microscopy monitoring facilitated by our system also allows us to observe heterogeneity in doxorubicin uptake within spheroids at the single-cell level. Combining optical sectioning microscopy with precise spatiotemporal oxygen control and 3D culture opens the door for a wide range of future studies on microenvironmental mechanisms driving cancer progression and resistance to anticancer therapy. These types of studies could facilitate future improvements in cancer diagnostics and treatment.

Merkel cell carcinoma in situ: New insights into the cells of origin.

We report a case of a 71-year-old male who presented with a small skin-coloured plaque on his cheek. Histopathology demonstrated an intraepidermal carcinoma with follicular involvement. No evidence of dermal invasion was seen. Immunohistochemical studies showed areas of positive staining for CK20, EMA and synaptophysin. Histopathology findings were found to be most consistent with a diagnosis of intraepidermal carcinoma with features of Merkel cell carcinoma in situ, in combination with a squamous cell carcinoma in situ, with follicular involvement. Recent advances and findings suggest Merkel cell polyomavirus MCPyV-positive Merkel cell carcinoma and MCPyV-negative Merkel cell carcinoma have different cells of origin from different germ layers.

A novel approach to producing uniform 3-D tumor spheroid constructs using ultrasound treatment.

Producing three-dimensional (3-D) multicellular tumor spheroids (TSs) is valuable for characterizing anticancer drugs since they provide a more representative model of the 3-D in vivo tumor than conventional two-dimensional (2-D) monolayer culture. The interaction of tumor cells with the extracellular matrix (ECM) in a 3-D culture environment is more similar to a tumor in vivo than in a 2-D environment; cell-cell and cell-ECM interaction can influence cell behaviour, such as in response to drug treatment. In vitro tumor spheroid models have been developed using microfluidic systems to generate 3-D hydrogel beads containing components of alginate and ECM protein, such as collagen, with high uniformity and throughput. Cell-laden hydrogel droplets are formed using a flow focusing process wherein the hydrogel precursors should be a homogeneous mixture. During gelation of the droplets into beads, the alginate acts as a fast gelling component helping to maintain the spherical shape of beads and preventing coalescence as the temperature-sensitive collagen I component gels more slowly. To produce uniform hydrogel droplets using the microfluidic flow focusing system, the mixtures must be homogeneous. However, collagen's sensitivity to temperature can lead to formation of chunks of collagen gel inside of the mixture, causing the mixture to become non-uniform and risking chip clogging. In order to overcome this limitation, previous approaches have used a cooling system during bead encapsulation while tumor cells were also present in the mixture, but this procedure can contribute to a delay in cell proliferation. Here a novel yet simple method is developed to prepare homogeneous pre-bead-encapsulation-mixtures containing collagen type I through ultrasonication. This method allows the cultivation of homogenous TS cultures with high uniformity and compact structure, and not only maintains cell viability but also the proliferation of cells in alginate/collagen hydrogel bead cultures. Depending on the sonication parameters, time and temperature, collagen can form small sized fibrils to thick fibers. Here, the mixtures containing collagen are assessed for morphology of collagen fibers/fibrils, cell viability, and proliferation. Human source Michigan Cancer Foundation-7 (MCF-7) breast cancer cells are successfully incorporated into alginate/collagen mixtures, followed by sonication, and then bead production. After bead gelation, the encapsulated MCF-7 cells remained viable and proliferated to form uniform TSs when the beads contained alginate and collagen. Results indicate that ultrasound treatment (UST) provides a powerful technique to change the structure of collagen from fiber to fibril, and to disperse collagen fibers in the mixture homogeneously for an application to generate uniform hydrogel beads and spheroids while not inhibiting cell proliferation.

Different in vitro cellular responses to tamoxifen treatment in polydimethylsiloxane-based devices compared to normal cell culture.

Cell culture systems based on polydimethylsiloxane (PDMS) microfluidic devices offer great flexibility because of their simple fabrication and adaptability. PDMS devices also make it straightforward to set up parallel experiments and can facilitate process automation, potentially speeding up the drug discovery process. However, cells grown in PDMS-based systems can develop in different ways to those grown with conventional culturing systems because of the differences in the containers' surfaces. Despite the growing number of studies on microfluidic cell culture devices, the differences in cellular behavior in PDMS-based devices and normal cell culture systems are poorly characterized. In this work, we investigated the proliferation and autophagy of MCF7 cells cultured in uncoated and Parylene-C coated PDMS wells. Using a quantitative method combining solid phase extraction and liquid chromatography mass spectrometry we developed, we showed that Tamoxifen uptake into the surfaces of uncoated PDMS wells can change the drug's effective concentration in the culture medium, affecting the results of Tamoxifen-induced autophagy and cytotoxicity assays. Such changes must be carefully analyzed before transferring in vitro experiments from a traditional culture environment to a PDMS-based microfluidic system. We also found that cells cultured in Parylene-C coated PDMS wells showed similar proliferation and drug response characteristics to cells cultured in standard polystyrene (PS) plates, indicating that Parylene-C deposition offers an easy way of limiting the uptake of small molecules into porous PDMS materials and significantly improves the performance of PDMS-based device for cell related research.