A novel pathway combining calreticulin exposure and ATP secretion in immunogenic cancer cell death

Surface-exposed calreticulin (ecto-CRT) and secreted ATP are crucial damage-associated molecular patterns (DAMPs) for immunogenic apoptosis. Inducers of immunogenic apoptosis rely on an endoplasmic reticulum (ER)-based (reactive oxygen species (ROS)-regulated) pathway for ecto-CRT induction, but the ATP secretion pathway is unknown. We found that after photodynamic therapy (PDT), which generates ROS-mediated ER stress, dying cancer cells undergo immunogenic apoptosis characterized by phenotypic maturation (CD80(high), CD83(high), CD86(high), MHC-II(high)) and functional stimulation (NO(high), IL-10(absent), IL-1β(high)) of dendritic cells as well as induction of a protective antitumour immune response. Intriguingly, early after PDT the cancer cells displayed ecto-CRT and secreted ATP before exhibiting biochemical signatures of apoptosis, through overlapping PERK-orchestrated pathways that require a functional secretory pathway and phosphoinositide 3-kinase (PI3K)-mediated plasma membrane/extracellular trafficking. Interestingly, eIF2α phosphorylation and caspase-8 signalling are dispensable for this ecto-CRT exposure. We also identified LRP1/CD91 as the surface docking site for ecto-CRT and found that depletion of PERK, PI3K p110α and LRP1 but not caspase-8 reduced the immunogenicity of the cancer cells. These results unravel a novel PERK-dependent subroutine for the early and simultaneous emission of two critical DAMPs following ROS-mediated ER stress.     

Bromopyruvate mediates autophagy and cardiolipin degradation to monolyso-cardiolipin in GL15 glioblastoma cells

The GL15 glioblastoma cell line undergoes viability loss upon treatment with bromopyruvate. The biochemical mechanisms triggered by the antiglycolytic agent indicate the activation of an autophagic pathway. Acridine orange stains acidic intracellular vesicles already 60 min after bromopyruvate treatment, whereas autophagosomes engulfing electron dense material are well evidenced 18 h later. The autophagic process is accompanied by the expression of the early autophagosomal marker Atg5 and by LC3-II formation, a late biochemical marker associated with autophagosomes. In agreement with the autophagic route activation, the inhibitory and the activator Akt and ERK signaling pathways are depressed and enhanced, respectively. In spite of the energetic collapse suffered by bromopyruvate-treated cells, MALDI-TOF mass spectrometry lipid analysis does not evidence a decrease of the major phospholipids, in accordance with the need of phospholipids for autophagosomal membranes biogenesis. Contrarily, mitochondrial cardiolipin decreases, accompanied by monolyso-cardiolipin formation and complete cytochrome c degradation, events that could target mitochondria to autophagy. However, in our experimental conditions cytochrome c degradation seems to be independent of the autophagic process.     

The endocannabinoid 2-arachidonoylglicerol decreases calcium induced cytochrome c release from liver mitochondria

2-Arachidonoylglicerol (2-AG) is an endocannabinoid that mimics the pharmacological effects of Δ⁹ tetrahydrocannabinol, the psychoactive component of the plant Cannabis sativa. It is present in many mammalian tissues, such as brain, liver, spleen, heart and kidney, where it exerts different biological effects either receptor mediated or independently of receptor activation. This work analyzes the effects of 2-AG on liver mitochondrial functions. It is shown that 2-AG causes a relevant decrease of calcium induced cyclosporine A sensitive cytochrome c release from mitochondria, a process representing an early event of the apoptotic program. Cyclosporin sensitive matrix swelling and ROS production measured under the same conditions are, on the contrary, almost unaffected or even enhanced, respectively, by 2-AG. Furthemore, 2-AG is found to stimulate resting state succinate oxidase activity and to inhibit oligomycin sensitive F_oF₁ ATP synthase activity. All these effects are apparently associated with 2-AG dependent alteration in the fluidity of the mitochondrial membranes, which was measured as generalized polarization of laurdan fluorescence.     

LIFE Experiment: Isolation of Cryptoendolithic Organisms from Antarctic Colonized Sandstone Exposed to Space and Simulated Mars Conditions on the International Space Station

Desiccated Antarctic rocks colonized by cryptoendolithic communities were exposed on the International Space Station (ISS) to space and simulated Mars conditions (LiFE-Lichens and Fungi Experiment). After 1.5?years in space samples were retrieved, rehydrated and spread on different culture media. Colonies of a green alga and a pink-coloured fungus developed on Malt-Agar medium; they were isolated from a sample exposed to simulated Mars conditions beneath a 0.1?%?T Suprasil neutral density filter and from a sample exposed to space vacuum without solar radiation exposure, respectively. None of the other flight samples showed any growth after incubation. The two organisms able to grow were identified at genus level by Small SubUnit (SSU) and Internal Transcribed Spacer (ITS) rDNA sequencing as Stichococcus sp. (green alga) and Acarospora sp. (lichenized fungal genus) respectively. The data in the present study provide experimental information on the possibility of eukaryotic life transfer from one planet to another by means of rocks and of survival in Mars environment.     

Increased arterial smooth muscle Ca2+ signaling, vasoconstriction, and myogenic reactivity in Milan hypertensive rats

The Milan hypertensive strain (MHS) rats are a genetic model of hypertension with adducin gene polymorphisms linked to enhanced renal tubular Na(+) reabsorption. Recently we demonstrated that Ca(2+) signaling is augmented in freshly isolated mesenteric artery myocytes from MHS rats. This is associated with greatly enhanced expression of Na(+)/Ca(2+) exchanger-1 (NCX1), C-type transient receptor potential (TRPC6) protein, and sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA2) compared with arteries from Milan normotensive strain (MNS) rats. Here, we test the hypothesis that the enhanced Ca(2+) signaling in MHS arterial smooth muscle is directly reflected in augmented vasoconstriction [myogenic and phenylephrine (PE)-evoked responses] in isolated mesenteric small arteries. Systolic blood pressure was higher in MHS (145 ± 1 mmHg) than in MNS (112 ± 1 mmHg; P < 0.001; n = 16 each) rats. Pressurized mesenteric resistance arteries from MHS rats had significantly augmented myogenic tone and reactivity and enhanced constriction to low-dose (1-100 nM) PE. Isolated MHS arterial myocytes exhibited approximately twofold increased peak Ca(2+) signals in response to 5 μM PE or ATP in the absence and presence of extracellular Ca(2+). These augmented responses are consistent with increased vasoconstrictor-evoked sarcoplasmic reticulum (SR) Ca(2+) release and increased Ca(2+) entry, respectively. The increased SR Ca(2+) release correlates with a doubling of inositol 1,4,5-trisphosphate receptor type 1 and tripling of SERCA2 expression. Pressurized MHS arteries also exhibited a ～70% increase in 100 nM ouabain-induced vasoconstriction compared with MNS arteries. These functional alterations reveal that, in a genetic model of hypertension linked to renal dysfunction, multiple mechanisms within the arterial myocytes contribute to enhanced Ca(2+) signaling and myogenic and vasoconstrictor-induced arterial constriction. MHS rats have elevated plasma levels of endogenous ouabain, which may initiate the protein upregulation and enhanced Ca(2+) signaling. These molecular and functional changes provide a mechanism for the increased peripheral vascular resistance (whole body autoregulation) that underlies the sustained hypertension.     

Primary thyroid angiosarcoma: an unusual localization

ABSTRACT: The finding of thyroid nodules is a very common occurrence in routine clinical practice. Approximately 5% to 7% of the entire population have thyroid nodules. Vascular lesions are one of the most controversial issues in thyroid pathology. These include benign lesions such as hemangiomas and, rarely, malignant tumors such as angiosarcomas or undifferentiated angiosarcomatoid carcinomas. In particular, angiosarcoma of the thyroid gland is a rare, highly aggressive malignant vascular tumor and in Italy the greatest geographical incidence of this lesion is witnessed near the Alps. Here, a case of thyroid angiosarcoma in a 71-year-old man with a history of goiter for about 20 years is described. The unusual localization of this lesion, the difficulties in reaching a definitive diagnosis for this particular histological type of primary tumor and a history of long-standing multinodular goiter in thyroid of an older man from outside the Alpine region prompted us to report this case of thyroid angiosarcoma mainly to discuss surgical, histopathological and immunohistochemical features.     

A strategy for young members within national radiation oncology societies: the Italian experience (AIRO Giovani group)

AimTo briefly review history, structure, past events and future projects of AIRO (Associazione Italiana Radioterapia Oncologica) young group (AIRO Giovani), focusing on its specific commitment to multidisciplnary networking among junior clinical oncologists at a national and international level.BackgroundAIRO Giovani is a part of AIRO composed by members under 40 years old. Its main activities are scientific and educational meetings dedicated to young Italian radiation oncologists and collaborative research projects.Materials and MethodsAIRO Giovani structure, events organized and supported by AIRO giovani as well as scientific activities are here reported from its creation in 2007 up to current days.ResultsAIRO Giovani group was able to create a consolidated network between Italian junior radiation oncologists, while opening the possibility to collaborate with junior groups of other national scientific societies in the field of oncology and with ESTRO young members. Scientific projects carried out by the group have been successful and will be further implemented in next years.ConclusionsAIRO Giovani is still in its infancy, but its early positive experience supports the creation and development of young groups within national radiation oncology societies.     

The discovery of how gender influences age immunological mechanisms in health and disease,and the identification of ageing gender-specific biomarkers,could lead to specifically tailored treatment and ultimately improve therapeutic success rates

The control of human health and diseases in the elderly population is becoming a challenge, since mean age and life expectation are progressively increasing as well as chronic degenerative diseases. These disorders are of complex diagnosis and they are difficult to be treated, but it is hoped that the predictive medicine will lead to more specific and effective treatment by using specific markers to identify persons with high risk of developing disease, before the clinical manifestation. Peripheral blood targets and biomarkers are currently the most practical, non-invasive means of disease diagnosing, predicting prognosis and therapeutic response. Human longevity is directly correlated with the optimal functioning of the immune system. Recent findings indicate that the sexual dimorphism of T helper (Th) cytokine pathways and the regulation of Th cell network homeostasis are normally present in the immune response and undergoes to adverse changes with ageing. Furthermore, immune senescence affects both men and women, but it does not affect them equally. Therefore, we hypothesize that the comprehension of the interferences between these gender specific pathways, the ageing immunological mechanism in pathological or healthy state and the current therapies, could lead to specifically tailored treatment and eventually improve the therapeutic success rates. Reaching this aim requires the identification of ageing gender-specific biomarkers that could easily reveal the above mentioned correlations.     

Behavioral Investigation on the Frames of Reference Involved in Visuomotor Transformations during Peripheral Arm Reaching

Background

Several psychophysical experiments found evidence for the involvement of gaze-centered and/or body-centered coordinates in arm-movement planning and execution. Here we aimed at investigating the frames of reference involved in the visuomotor transformations for reaching towards visual targets in space by taking target eccentricity and performing hand into account.

Methodology/Principal Findings

We examined several performance measures while subjects reached, in complete darkness, memorized targets situated at different locations relative to the gaze and/or to the body, thus distinguishing between an eye-centered and a body-centered frame of reference involved in the computation of the movement vector. The errors seem to be mainly affected by the visual hemifield of the target, independently from its location relative to the body, with an overestimation error in the horizontal reaching dimension (retinal exaggeration effect). The use of several target locations within the perifoveal visual field allowed us to reveal a novel finding, that is, a positive linear correlation between horizontal overestimation errors and target retinal eccentricity. In addition, we found an independent influence of the performing hand on the visuomotor transformation process, with each hand misreaching towards the ipsilateral side.

Conclusions

While supporting the existence of an internal mechanism of target-effector integration in multiple frames of reference, the present data, especially the linear overshoot at small target eccentricities, clearly indicate the primary role of gaze-centered coding of target location in the visuomotor transformation for reaching.