Search

High-grade neuroendocrine carcinoma (HGNEC) is subclassified into small cell carcinoma (SmCC) and large cell neuroendocrine carcinoma (LCNEC). Although both are clinically aggressive, the SmCC and LCNEC need to have different treatment strategies, and accurate pathologic diagnosis is challenging. We studied a large retrospective cohort (186 cases) of HGNEC of bladder and lung to investigate the abundance of cytokeratin (CK) 7 expression and staining pattern in SmCC and LCNEC. Overall, the pulmonary and urinary HGNEC exhibited several different CK7 staining patterns, including negative staining (n=28), dot-like staining (n=73), partial membranous staining (n=26), and complete membranous staining (n=60). Overall, 88.9% (44/49) of pulmonary SmCC and 88.0% (44/50) of urinary SmCC showed negative or dot-like patterns for CK7, while 90.8% (59/65) of pulmonary LCNEC and 72.7% (16/22) of urinary LCNEC showed partial or complete membranous patterns for CK7 (χ 2 =105.05, P0.0001). The distinct staining patterns were also present in those mixed SmCC and LCNEC. In addition, the specimen types or fixation did not affect CK7 staining patterns. In conclusion, CK7 has a high differential value for SmCC and LCNEC and could help guide personalized treatment for patients.

Introduction: Hemophagocytic lymphohistiocytosis (HLH) is a rare condition and furthermore human immunodeficiency virus (HIV)-associated HLH is rarely reported in the literature. The most frequent presentation of secondary HLH is in association with infections, malignancies or drugs. In HIV-positive patients, the viral infection itself or the antiretroviral therapy (ART) could trigger HLH. Case presentation: A 14-year-old boy was admitted for persistent diarrhea, severe weight loss and chest burns. Laboratory tests revealed important neutropenia, which led to HIV infection diagnosis. ART in combination was started associated with granulocyte-colony stimulating factor. Viral copies declined after six weeks of treatment, but the cluster of differentiation 4 (CD4) T-lymphocytes and neutrophil counts remained very low. Infections and malignancies were ruled out. The bone marrow aspirate revealed hemophagocytosis which in association with fever, bicytopenia, hypofibrinogenemia and hypertriglyceridemia established HLH diagnosis. Cortisone therapy and intravenous immunoglobulins were added. Due to lack of response, HLH-2004 protocol was initiated in collaboration with pediatric hematologist. In the first six months of treatment, CD4 T-lymphocytes and neutrophil count remained low and then they showed significant increase simultaneously. During treatment, the patient developed spontaneous severe back pain. Magnetic resonance imaging showed vertebral compression, osteomalacia and a thoracic vertebral fracture. Conclusions: Having ruled out the usual associated infections and malignancies, this is a case of HIV-associated with HLH. In this case, only the ART and immunomodulatory therapy were not enough and failed to work. Systemic immunosuppression also worked only after a prolonged course which led to an unfortunate complication: a vertebral fracture.

Assessment of programmed death-ligand 1 (PD-L1) expression and CD8+ lymphocyte infiltrates in triple-negative breast carcinoma (TNBC) can provide valuable prognostic and predictive information. Knowledge of clinical and pathological factors that predict the status of these two markers is needed to better select patients likely to respond to immunotherapy. We aim to assess the association between histological subtypes of TNBC and tumor microenvironment type, defined here as each tumor's PD-L1 status and the percentage of CD8+ cells in its tumor-associated lymphocyte population. Tissue microarrays consisting of 72 TNBC cases (28 conventional invasive ductal carcinomas (IDCs), 21 basal-like IDCs, 18 apocrine carcinomas, and five metaplastic carcinomas) were evaluated for PD-L1 expression using the SP142 and 22C3 immunohistochemical (IHC) assays. The percentages of CD8+ and CD4+ intra-tumoral stromal lymphocytes in each case were analyzed using QuPath (open-source software platform) on CD8 and CD4 IHC-stained digital slides of the TMAs. Tumor-infiltrating lymphocytes (TILs) were also assessed on representative HE-stained whole-tissue sections and compared to CD8+ and CD4+ lymphocyte percentages, and to the CD4/CD8 ratio of intra-tumoral lymphocytes for each case. Cases were then separated into four tumor microenvironment groups (PD-L1+/CD8+, PD-L1+/CD8-, PD-L1-/CD8+, and PD-L1-/CD8-). Basal-like IDCs were most often PD-L1-/CD8- (71.4%/61.9% of cases with SP142/22C3, respectively), while conventional IDCs were more distributed among PD-L1+ and PD-L1- microenvironments (35.7% PD-L1+/CD8+ and 42.9% PD-L1-/CD8- with the 22C3 assay). Apocrine carcinomas tended to be PD-L1-/CD8- (83.3% of cases with both SP142 and 22C3 antibodies). Metaplastic carcinomas were PD-L1-/CD8- in 60% of cases with both 22C3 and SP142. A CD8+ lymphocyte percentage ≥5% strongly predicted PD-L1 positivity (positive predictive value using the 22C3 assay: 0.75). Our data suggest that some histological subtypes of TNBC are predictive of PD-L1 status and CD8+ T-cell infiltrate levels.

Prader-Willi Syndrome is a complex congenital disorder characterized by neonatal hypotonia, short stature, childhood...

We have investigated the growth-suppressive action of epigallocatechin-3-gallate (EGCG) on human leukemia Jurkat T cells. Results show a strong correlation between the dose-dependent reduction of clonogenic survival following acute EGCG treatments and the EGCG-induced decline of the mitochondrial level of Ca(2+). The cell killing ability of EGCG was synergistically enhanced by menadione. In addition, the cytotoxic effect of EGCG applied alone or in combination with menadione was accompanied by apoptosis induction. We also observed that in acute treatments EGCG displays strong antioxidant properties in the intracellular milieu, but concurrently triggers some oxidative stress generating mechanisms that can fully develop on a longer timescale. In parallel, EGCG dose-dependently induced mitochondrial depolarization during exposure, but this condition was subsequently reversed to a persistent hyperpolarized mitochondrial state that was dependent on the activity of respiratory Complex I. Fluorimetric measurements suggest that EGCG is a mitochondrial Complex III inhibitor and indicate that EGCG evokes a specific cellular fluorescence with emission at 400nm and two main excitation bands (at 330nm and 350nm) that may originate from a mitochondrial supercomplex containing dimeric Complex III and dimeric ATP-synthase, and therefore could provide a valuable means to characterize the functional properties of the respiratory chain.

Cell membrane fluidity, which can be altered by oxidative stress, plays an important role in the cell physiology. Flavonoids are among the most studied food substances that prevent and/or reduce oxidative stress, but their action mechanisms are far from being understood. We performed a study on the effect of quercetin and epigallocatechin-3-gallate on 2-Dimyristoyl-sn-glycero-3-phosphocholine small unilamellar vesicles (SUVs) with different amounts of cholesterol, using Laurdan as a fluorescent probe, to put into evidence the perturbations of the phospholipid membrane fluidity and local lipid order in an attempt to decipher the action mechanism of the flavonoids at the cell membrane level. Results indicate that polyphenols modulate the transition from the gel phase to the liquid crystalline phase of SUVs in all studied membranes. SUVs with cholesterol have by themselves higher phase transition temperature and the presence of polyphenols stabilizes further the membrane. Quercetin has a dose-dependent effect on the fluidity and local order of the lipid membranes, whilst epigallocatechin-3-gallate action is not dose-dependent, the differences being attributable to the hydrophobic/hydrophilic character of the substances. The findings are discussed within the frame of earlier reports on the effect of polyphenols on artificial membranes.

Quercetin (QCT) is an important bioactive natural compound found in numerous edible plants. Since the lipid bilayer represents an essential compound of the cell membrane, QCT's direct interaction with this structure is of great interest. Therefore, we proposed to study the effects of QCT on DMPC liposomes containing cholesterol (Chol), and for this purpose Laurdan fluorescence was used. As a fluorescent probe, Laurdan is able to detect changes in membrane phase properties. When incorporated in lipid bilayers, Laurdan emits from two different excited states, a non-relaxed one when the bilayer packing is tight and a relaxed state when the bilayer packing is loose. The main tool for quantifying QCT's effects on phospholipid membranes containing Chol has been the analysis, the decomposition of Laurdan emission spectra in sums of two Gaussian functions on energy. This kind of approach has allowed good analysis of the balance between the two emitting states of Laurdan. Our results show that both Laurdan emission states are present to different extents in a wide temperature range for DMPC liposomes with Chol. QCT is decreasing the phase transition temperature in pure DMPC liposomes as proved by generalized polarization (GP) values. QCT also quenches Laurdan fluorescence, depending on the temperature and the presence of Chol in the membrane. Stern-Volmer constants were calculated for different lipid membrane compositions, and the conclusion was that the relaxed state favors the nonradiative transitions of the fluorophore.

We report new analytical results for the behaviour of the free energy of an ion between two media that are characterized by different dielectric permitivities including the ion polarizability as a phenomenological parameter. The differences in the free energy induced by the new terms related to the polarizability are on the order of a few k B T (∼25 meV), k B being the Boltzmann constant and T the temperature of the system not far from the room temperature, and may explain the enhanced propensity of halogen anions for the water–air or water–lipid interfaces with increasing ionic polarizability.

The flavonoid quercetin and menadione (vitamin K3) are known as potent apoptogens in human leukemia Jurkat T cells. We explored some underlying mechanisms and the potential relevance of the combination quercetin-menadione for clinical applications. In acute treatments, quercetin manifested a strong antioxidant character, but induced a transient loss of Δψm, likely mediated by opening of the mitochondrial permeability transition pore. After removal of quercetin, persistent mitochondrial hyperpolarization was generated via stimulation of respiratory Complex I. In contrast, menadione-induced Δψm dissipation was only partially and transiently reversed after menadione removal. Results indicate that Ca(2+) release is a necessary event in quercetin-induced cell death and that the survival response to quercetin is delineated within 1h from exposure. Depending on dose, the two agents exhibited either antagonistic or synergistic effects in reducing clonogenicity of Jurkat cells. 24-h combinatorial regimens at equimolar concentrations of 10-15 μM, which are compatible with a clinically achievable (and safe) scheme, reduced cell viability at efficient rates. Altogether, these findings support the idea that the combination quercetin-menadione could improve the outcome of conventional leukemia therapies, and warrant the utility of additional studies to investigate the therapeutic effects of this combination in different cellular or animal models for leukemia.

The role of mitochondrial complex I in ultraweak photon-induced delayed photon emission (delayed luminescence (DL)) of human leukemia Jurkat T cells was probed by using complex I targeting agents like rotenone, menadione, and quercetin. Rotenone, a complex I-specific inhibitor, dose-dependently increased the mitochondrial level of reduced nicotinamide adenine dinucleotide (NADH), decreased clonogenic survival, and induced apoptosis. A strong correlation was found between the mitochondrial levels of NADH and oxidized flavin mononucleotide (FMNox) in rotenone-, menadione- and quercetin-treated cells. Rotenone enhanced DL dose-dependently, whereas quercetin and menadione inhibited DL as well as NADH or FMNox. Collectively, the data suggest that DL of Jurkat cells originates mainly from mitochondrial complex I, which functions predomi- nantly as a dimer and less frequently as a tetramer. In individual monomers, both pairs of pyridine nucleotide (NADH/reduced nicotinamide adenine dinucleotide phosphate) sites and flavin (FMN-a/FMN-b) sites appear to bind cooperatively their specific ligands. Enhancement of delayed red-light emission by rotenone suggests that the mean time for one-electron reduction of ubiquinone or FMN-a by the terminal Fe/S center (N2) is 20 or 284 μs, respectively. All these findings suggest that DL spectroscopy could be used as a reliable, sensitive, and robust technique to probe electron flow within complex I in situ. © 2013 Society of Photo-Optical Instrumentation

Quercetin and epigallocatechin gallate are two of the most abundant polyphenols in dietary plants, including apples, onions, red wine and green tea. The bioactivity of polyphenols is linked to their ability to interact with cell membranes without being internalized. The aim of the present study was to assess the short-time effect of these polyphenols on membrane anisotropy and transmembrane potential of U937 monocytes and Jurkat T lymphoblasts. Results showed that quercetin and epigallocatechin gallate induced, after 20 minutes cell exposure, a dose-dependent increase of membrane anisotropy and polarization. Anisotropy increase was correlated with the reduction of lipid peroxidation. Our results could indicate that the antioxidant capacity of the tested polyphenols is due to their stabilizing effect on the cell membranes, thus contributing to cell protection in various pathologies and as adjuvant therapy in highly toxic treatment regimens.

Hermansky-Pudlak syndrome (HPS) is a rare heterogeneously inherited autosomal recessive group of disorders presenting with oculocutaneous albinism, bleeding diathesis and pulmonary disease. HPS is thought to occur as a consequence of disturbed formation or trafficking of intracellular vesicles, most importantly, melanosomes, platelet dense granules and lysosomes. The latter finding, in particular, contributes much to the morbidity associated with the disease, as ceroid lipofuscin deposits in lysosomes affect many organ systems. This is especially problematic in the lungs where it is often associated with pulmonary fibrosis and premature death. Currently, there are 7 known HPS genes in humans. In the mouse, at least 16 known HPS genes produce HPS-mutant phenotypes. The HPS gene mutation is considered to be one of the most prevalent single-gene disorders in northwest Puerto Rico, home to the largest cohort of known patients. In HPS, interventions addressing the bleeding diathesis and pulmonary fibrosis are often disappointingly ineffectual. Pirfenidone, a novel compound with documented anti-inflammatory, antioxidant and antifibrotic effects, appears to hold promise in delaying or preventing fibrosis. To date, there has been one successful lung transplant performed on a patient with HPS. We present a patient with HPS and review the current literature on our understanding of this rare disorder.

The aesthetic appearance after the treatment of orbito-sinusal tumors can sometimes be dramatic. In this study we compared exenteration versus conservative procedures (survival rate, Visual Quality of Life (QoL) and Social QoL. Findings: 23 patients underwent exenteration and 43 conservative surgery. The probability for surviving was almost equal at 2 and 5 years and. the social QoL was also similar (p>0.202). The visual QoL was significantly lower in the patients that underwent exenteration surgery (p Conclusions QoL aspects should be considered when choosing treatment for orbito-sinusal tumors.