Unique pattern of neutrophil migration and function during tumor progression.

Although neutrophils have been linked to the formation of the pre-metastatic niche, the mechanism of their migration to distant, uninvolved tissues has remained elusive. We report that bone marrow neutrophils from mice with early-stage cancer exhibited much more spontaneous migration than that of control neutrophils from tumor-free mice. These cells lacked immunosuppressive activity but had elevated rates of oxidative phosphorylation and glycolysis, and increased production of ATP, relative to that of control neutrophils. Their enhanced spontaneous migration was mediated by autocrine ATP signaling through purinergic receptors. In ectopic tumor models and late stages of cancer, bone marrow neutrophils demonstrated potent immunosuppressive activity. However, these cells had metabolic and migratory activity indistinguishable from that of control neutrophils. A similar pattern of migration was observed for neutrophils and polymorphonuclear myeloid-derived suppressor cells from patients with cancer. These results elucidate the dynamic changes that neutrophils undergo in cancer and demonstrate the mechanism of neutrophils' contribution to early tumor dissemination.

CD45 Phosphatase Inhibits STAT3 Transcription Factor Activity in Myeloid Cells and Promotes Tumor-Associated Macrophage Differentiation.

Recruitment of monocytic myeloid-derived suppressor cells (MDSCs) and differentiation of tumor-associated macrophages (TAMs) are the major factors contributing to tumor progression and metastasis. We demonstrated that differentiation of TAMs in tumor site from monocytic precursors was controlled by downregulation of the activity of the transcription factor STAT3. Decreased STAT3 activity was caused by hypoxia and affected all myeloid cells but was not observed in tumor cells. Upregulation of CD45 tyrosine phosphatase activity in MDSCs exposed to hypoxia in tumor site was responsible for downregulation of STAT3. This effect was mediated by the disruption of CD45 protein dimerization regulated by sialic acid. Thus, STAT3 has a unique function in the tumor environment in controlling the differentiation of MDSC into TAM, and its regulatory pathway could be a potential target for therapy.

Ghost mitochondria drive metastasis through adaptive GCN2/Akt therapeutic vulnerability.

Cancer metabolism, including in mitochondria, is a disease hallmark and therapeutic target, but its regulation is poorly understood. Here, we show that many human tumors have heterogeneous and often reduced levels of Mic60, or Mitofilin, an essential scaffold of mitochondrial structure. Despite a catastrophic collapse of mitochondrial integrity, loss of bioenergetics, and oxidative damage, tumors with Mic60 depletion slow down cell proliferation, evade cell death, and activate a nuclear gene expression program of innate immunity and cytokine/chemokine signaling. In turn, this induces epithelial-mesenchymal transition (EMT), activates tumor cell movements through exaggerated mitochondrial dynamics, and promotes metastatic dissemination in vivo. In a small-molecule drug screen, compensatory activation of stress response (GCN2) and survival (Akt) signaling maintains the viability of Mic60-low tumors and provides a selective therapeutic vulnerability. These data demonstrate that acutely damaged, "ghost" mitochondria drive tumor progression and expose an actionable therapeutic target in metastasis-prone cancers.

Parkin ubiquitination of Kindlin-2 enables mitochondria-associated metastasis suppression.

Mitochondria are signaling organelles implicated in cancer, but the mechanisms are elusive. Here, we show that Parkin, an E3 ubiquitination (Ub) ligase altered in Parkinson's disease, forms a complex with the regulator of cell motility, Kindlin-2 (K2), at mitochondria of tumor cells. In turn, Parkin ubiquitinates Lys581 and Lys582 using Lys48 linkages, resulting in proteasomal degradation of K2 and shortened half-life from ∼5 h to ∼1.5 h. Loss of K2 inhibits focal adhesion turnover and ß1 integrin activation, impairs membrane lamellipodia size and frequency, and inhibits mitochondrial dynamics, altogether suppressing tumor cell-extracellular matrix interactions, migration, and invasion. Conversely, Parkin does not affect tumor cell proliferation, cell cycle transitions, or apoptosis. Expression of a Parkin Ub-resistant K2 Lys581Ala/Lys582Ala double mutant is sufficient to restore membrane lamellipodia dynamics, correct mitochondrial fusion/fission, and preserve single-cell migration and invasion. In a 3D model of mammary gland developmental morphogenesis, impaired K2 Ub drives multiple oncogenic traits of EMT, increased cell proliferation, reduced apoptosis, and disrupted basal-apical polarity. Therefore, deregulated K2 is a potent oncogene, and its Ub by Parkin enables mitochondria-associated metastasis suppression.

Safety and feasibility of a functional electrical stimulation cycling-based muscular dysfunction diagnostic method in mechanically ventilated patients.

BACKGROUND: A nonvolitional diagnostic method based on FES-Cycling technology has recently been demonstrated for mechanically ventilated patients. This method presents good sensitivity and specificity for detecting muscle dysfunction and survival prognosis, even in unconscious patients. As the clinical relevance of this method has already been reported, we aimed to evaluate its safety and feasibility. METHODS: An observational prospective study was carried out with 20 critically ill, mechanically ventilated patients. The FES-cycling equipment was set in a specific diagnostic mode. For safety determination, hemodynamic parameters and peripheral oxygen saturation were measured before and immediately after the diagnostic protocol, as well as venous oxygen saturation and blood lactate. The creatine phosphokinase level (CPK) was measured before and 24, 48, and 72 h after the test. The time taken to carry out the entire diagnostic protocol and the number of patients with visible muscle contraction (capacity of perceptive muscular recruitment) were recorded to assess feasibility. RESULTS: Heart rate [91 ± 23 vs. 94 ± 23 bpm (p = 0.0837)], systolic [122 ± 19 vs. 124 ± 19 mm Hg (p = 0.4261)] and diastolic blood pressure [68 ± 13 vs. 70 ± 15 mm Hg (p = 0.3462)], and peripheral [98 (96-99) vs. 98 (95-99) % (p = 0.6353)] and venous oxygen saturation [71 ± 14 vs. 69 ± 14% (p = 0.1317)] did not change after the diagnostic protocol. Moreover, blood lactate [1.48 ± 0.65 vs. 1.53 ± 0.71 mmol/L (p = 0.2320)] did not change. CPK did not change up to 72 h after the test [99 (59-422) vs. 125 (66-674) (p = 0.2799) vs. 161 (66-352) (p > 0.999) vs. 100 (33-409) (p = 0.5901)]. The time taken to perform the diagnostic assessment was 11.3 ± 1.1 min. In addition, 75% of the patients presented very visible muscle contractions, and 25% of them presented barely visible muscle contractions. CONCLUSIONS: The FES cycling-based muscular dysfunction diagnostic method is safe and feasible. Hemodynamic parameters, peripheral oxygen saturation, venous oxygen saturation, and blood lactate did not change after the diagnostic protocol. The muscle damage marker (CPK) did not increase up to 72 h after the diagnostic protocol.

Development of new 1, 3-dihydroxyacridone derivatives as Akt pathway inhibitors in skeletal muscle cells.

In the present work, four new compounds based on the privileged structure acridone were efficiently synthesized following simple operational techniques and biologically tested on proliferative skeletal muscle cells (C2C12) and rhabdomyosarcoma cells (RD) showing no significant changes in the number of dead or viable cells at 1 µM during 24 or 48 h of treatment. Of relevance, acridone derivatives 3a-3d at 0.5 µM for 24 h effectively inhibited Akt activation in C2C12, while at 1 µM only compounds 3a and 3b have effect. RD cells showed a different response pattern. These cells treated with 3a (0.5 µM), 3b (0.5 µM) or 3d (0.5 or 1 µM) for 24 h shown significant Akt inhibition. In addition, 3a-3d assayed at 1 µM for 48 h were highly successful in inhibiting Akt phosphorylation. Finally, based on molecular docking and molecular dynamics simulations, we rationalize the experimental results mentioned above and propose that 3-phosphoinositide-dependent kinase-1 (PDK1) could be one of the molecular targets of this new series of 1, 3-dihydroxyacridone derivatives. Biological and in silico studies revealed that 3b could be considered as the most promising prototype for the development of new antitumor agents.

Sex reversal of pejerrey (Odontesthes bonariensis), a species with temperature-dependent sex determination, in a seminatural environment.

This study examined the changes in sex ratios and sex reversal rates in pejerrey Odontesthes bonariensis that occur with the progression of the spawning season in a seminatural setting. Four groups of hatchery-produced pejerrey larvae were stocked in floating cages in La Salada de Monasterio lake (Pampas region), a natural habitat of this species, and reared from hatching beyond gonadal sex determination with minimum human interference. Cage 1 was stocked at the beginning of the spring spawning season and the other cages were stocked with monthly delays until cage 4 in early summer. The genotypic (amhy+, XY/YY; amhy-, XX) and phenotypic (testis, male; ovary, female) sex ratios and proportions of genotype/phenotype mismatched individuals were estimated and their relation to water temperature and daylength during the experiment was analysed by generalized linear modelling. Water temperature varied between 11 and 30.5°C, and daylength duration between 11 h 22 min and 14 h 35 min. Sex genotyping revealed nearly balanced sex ratios of XY/YY (46%-49.1%) and XX (50.9%-54%) fish in cages 2-4 whereas the genotypic sex ratio in cage 1 was clearly biased towards XY/YY fish (60.6%). Phenotypic males ranged from 42% to 54.4% in cages 1-3. Cage 4, in turn, had significantly more phenotypic males (66%). The percentage of XX males (phenotypic male/genotypic female) was 23.1% in cage 1, decreased to a minimum of 5.4% in cage 2 and gradually increased in cages 3 and 4 to a maximum of 40.7% in the latter. The percentages of XY/YY females (phenotypic female/genotypic male) were highest in cage 1 (30%) and decreased progressively in the other cages to a significantly lower value (4.3%) in cage 4. These results generally support the findings of laboratory studies on the effect of temperature on the sex determination of this species and also provide novel evidence of a XX genotype-specific masculinizing effect of short daylength.

Assessment of COVID-19 Positive Rates Amongst COVID-19 Close Contacts Through the Health Risk Warning System.

From 6 Jan 22 to 17 Feb 22, a total of 729,367 close contacts classified into four distinct groups (i.e., household, social, school and nursing/ welfare home contacts) were managed by the Health Risk Warning system. High COVID-19-positive rates were demonstrated amongst household contacts, i.e., 10.9% (37,220/342,302) were detected via antigen rapid test kits and 56.5% (4,952/8,767) were detected via polymerase chain reaction testing. Household contacts represent the highest risk of being infected by virtue of the sustained close-proximity interactions in the household setting. Social, school and nursing/ welfare home contacts continue to remain at-risk groups for close monitoring. At a population level, household and symptomatic close contacts should be the groups of focus in the early phases of the pandemic, including future potential waves involving COVID-19 variants of concern.

Survivin at a glance.

Survivin (also known as BIRC5) is an evolutionarily conserved eukaryotic protein that is essential for cell division and can inhibit cell death. Normally it is only expressed in actively proliferating cells, but is upregulated in most, if not all cancers; consequently, it has received significant attention as a potential oncotherapeutic target. In this Cell Science at a Glance article and accompanying poster, we summarise our knowledge of survivin 21 years on from its initial discovery. We describe the structure, expression and function of survivin, highlight its interactome and conclude by describing anti-survivin strategies being trialled.

Gonadal development in pejerrey (Odontesthes bonariensis) during spawning season in relation with sex steroids and temperature variation in Gómez lake (Pampas region, Argentina).

Gómez lake (34 ° 39 'S 61 ° 01' W) is a typical shallow lake of Pampas region placed in the upper area of the Salado river. The most abundant fish species in this lake is the pejerrey (Odontesthes bonariensis) valued due to the quality of its flesh and its attractiveness as a game fish. The aim of this study was to describe for the first time in this pejerrey wild population the gonadal stages during three consecutive spawning seasons (August to December) in relation with sexual steroids and temperature in this lake. In general, pejerrey gonadal development, the gonadosomatic index and the plasma levels of estradiol and testosterone varied in relation to air temperature. During the sampling period, pejerrey females started to ovulate in early August (winter), with a peak in October and ending in December with some of them with atretic oocytes. For males, it was possible to find spermiating animals during the whole spawning season and some arrested animals only in December. Our results confirm the relationship with pejerrey maturation and temperature and can be useful for decision making in the management of this natural resource.

Myc-mediated transcriptional regulation of the mitochondrial chaperone TRAP1 controls primary and metastatic tumor growth.

The role of mitochondria in cancer continues to be debated, and whether exploitation of mitochondrial functions is a general hallmark of malignancy or a tumor- or context-specific response is still unknown. Using a variety of cancer cell lines and several technical approaches, including siRNA-mediated gene silencing, ChIP assays, global metabolomics and focused metabolite analyses, bioenergetics, and cell viability assays, we show that two oncogenic Myc proteins, c-Myc and N-Myc, transcriptionally control the expression of the mitochondrial chaperone TNFR-associated protein-1 (TRAP1) in cancer. In turn, this Myc-mediated regulation preserved the folding and function of mitochondrial oxidative phosphorylation (OXPHOS) complex II and IV subunits, dampened reactive oxygen species production, and enabled oxidative bioenergetics in tumor cells. Of note, we found that genetic or pharmacological targeting of this pathway shuts off tumor cell motility and invasion, kills Myc-expressing cells in a TRAP1-dependent manner, and suppresses primary and metastatic tumor growth in vivo We conclude that exploitation of mitochondrial functions is a general trait of tumorigenesis and that this reliance of cancer cells on mitochondrial OXPHOS pathways could offer an actionable therapeutic target in the clinic.

Syntaphilin Is a Novel Biphasic Biomarker of Aggressive Prostate Cancer and a Metastasis Predictor.

Easily accessible biomarkers that may inform on the metastatic potential of localized prostate cancer are urgently needed. Herein, we show that syntaphilin (SNPH), a molecule originally identified as a negative regulator of mitochondrial dynamics in neurons, is abundantly expressed in prostate cancer. SNPH distribution in prostate cancer is spatially biphasic, with high expression at the invasive front, correlating with increased proliferative rates, as determined by Ki-67 labeling, and reduced levels in the central tumor bulk, which are further decreased in patients with distant metastases. Higher levels of SNPH are observed with increasing Gleason grade. Prostate tumors predominantly express a novel, extraneuronal isoform of SNPH that accumulates in mitochondria and maintains oxidative metabolism and tumor cell proliferation. These data suggest that SNPH is a novel marker of high Gleason grade prostate cancer, differentially expressed at the invasive front compared with the central tumor bulk, and is potentially down-regulated in metastatic disease. This biphasic pattern of expression may reflect a dual function of SNPH in controlling the balance between cell proliferation and invasion in tumors.

IDH2 reprograms mitochondrial dynamics in cancer through a HIF-1α-regulated pseudohypoxic state.

The role of mitochondria in cancer continues to be debated and paradoxically implicated in opposing functions in tumor growth and tumor suppression. To understand this dichotomy, we explored the function of mitochondrial isocitrate dehydrogenase (IDH)2, a tricarboxylic acid cycle enzyme mutated in subsets of acute leukemias and gliomas, in cancer. Silencing of IDH2 in prostate cancer cells impaired oxidative bioenergetics, elevated reactive oxygen species (ROS) production, and promoted exaggerated mitochondrial dynamics. This was associated with increased subcellular mitochondrial trafficking, turnover of membrane focal adhesion complexes, and enhanced tumor cell migration and invasion, without changes in cell cycle progression. Mechanistically, loss of IDH2 caused ROS-dependent stabilization of hypoxia-inducible factor-1α in normoxia, which was required for increased mitochondrial trafficking and tumor cell movements. Therefore, IDH2 is a dual regulator of cancer bioenergetics and tumor cell motility. This pathway may reprogram mitochondrial dynamics to differentially adjust energy production or promote tumor cell invasion in response to microenvironment conditions.-Wang, Y., Agarwal, E., Bertolini, I., Ghosh, J. C., Seo, J. H., Altieri, D. C. IDH2 reprograms mitochondrial dynamics in cancer through a HIF-1α-regulated pseudohypoxic state.

Mitochondrial dynamics and metastasis.

Changes in cellular metabolism are now a recognized hallmark of cancer. Although this process is ripe with therapeutic potential in the clinic, its complexity and extraordinary plasticity have systematically defied dogmas and oversimplifications. Perhaps, best exemplifying this intricacy is the role of mitochondria in cancer, which in just a few years has gone from largely unnoticed to pivotal disease driver. The underlying mechanisms are only beginning to emerge. However, there is now clear evidence linking the dynamic nature of mitochondria to the machinery of tumor cell motility and metastatic spreading. These studies may open fresh therapeutic options for patients with disseminated cancer, currently an incurable and mostly lethal condition.

Evidence of a landlocked reproducing population of the marine pejerrey Odontesthes argentinensis (Actinopterygii; Atherinopsidae).

In South America, the order Atheriniformes includes the monophyletic genus Odontesthes with 20 species that inhabit freshwater, estuarine and coastal environments. Pejerrey Odontesthes argentinensis is widely distributed in coastal and estuarine areas of the Atlantic Ocean and is known to foray into estuaries of river systems, particularly in conditions of elevated salinity. However, to our knowledge, a landlocked self-sustaining population has never been recorded. In this study, we examined the pejerrey population of Salada de Pedro Luro Lake (south-east of Buenos Aires Province, Argentina) to clarify its taxonomic identity. An integrative taxonomic analysis based on traditional meristic, landmark-based morphometrics and genetic techniques suggests that the Salada de Pedro Luro pejerrey population represents a novel case of physiological and morphological adaptation of a marine pejerrey species to a landlocked environment and emphasises the environmental plasticity of this group of fishes.

The Mitochondrial Unfoldase-Peptidase Complex ClpXP Controls Bioenergetics Stress and Metastasis.

Mitochondria must buffer the risk of proteotoxic stress to preserve bioenergetics, but the role of these mechanisms in disease is poorly understood. Using a proteomics screen, we now show that the mitochondrial unfoldase-peptidase complex ClpXP associates with the oncoprotein survivin and the respiratory chain Complex II subunit succinate dehydrogenase B (SDHB) in mitochondria of tumor cells. Knockdown of ClpXP subunits ClpP or ClpX induces the accumulation of misfolded SDHB, impairing oxidative phosphorylation and ATP production while activating "stress" signals of 5' adenosine monophosphate-activated protein kinase (AMPK) phosphorylation and autophagy. Deregulated mitochondrial respiration induced by ClpXP targeting causes oxidative stress, which in turn reduces tumor cell proliferation, suppresses cell motility, and abolishes metastatic dissemination in vivo. ClpP is universally overexpressed in primary and metastatic human cancer, correlating with shortened patient survival. Therefore, tumors exploit ClpXP-directed proteostasis to maintain mitochondrial bioenergetics, buffer oxidative stress, and enable metastatic competence. This pathway may provide a "drugable" therapeutic target in cancer.

Organocatalytic Synthesis of Benzazetidines by Trapping Hemiaminals with Protecting Groups.

Benzazetidines are highly strained and inherently unstable heterocycles. There are only few methodologies for assembling these compounds. Here, a protocol is presented to trap an elusive cyclic, four-membered hemiaminal structure. This method affords several benzazetidines in moderate to good yields (up to 81%), and it uses inexpensive materials and does not require catalysts based on transition metals. The high ring strain energy of these benzazetidine systems was estimated by density functional theory calculations to be about 32 kcal mol-1. This synthesis can be applied also on gram scale with reaction yield essentially unchanged.

Mitochondrial HSP90 Accumulation Promotes Vascular Remodeling in Pulmonary Arterial Hypertension.

RATIONALE: Pulmonary arterial hypertension (PAH) is a vascular remodeling disease with a poor prognosis and limited therapeutic options. Although the mechanisms contributing to vascular remodeling in PAH are still unclear, several features, including hyperproliferation and resistance to apoptosis of pulmonary artery smooth muscle cells (PASMCs), have led to the emergence of the cancer-like concept. The molecular chaperone HSP90 (heat shock protein 90) is directly associated with malignant growth and proliferation under stress conditions. In addition to being highly expressed in the cytosol, HSP90 exists in a subcellular pool compartmentalized in the mitochondria (mtHSP90) of tumor cells, but not in normal cells, where it promotes cell survival. OBJECTIVES: We hypothesized that mtHSP90 in PAH-PASMCs represents a protective mechanism against stress, promoting their proliferation and resistance to apoptosis. METHODS: Expression and localization of HSP90 were analyzed by Western blot, immunofluorescence, and immunogold electron microscopy. In vitro, effects of mtHSP90 inhibition on mitochondrial DNA integrity, bioenergetics, cell proliferation and resistance to apoptosis were assessed. In vivo, the therapeutic potential of Gamitrinib, a mitochondria-targeted HSP90 inhibitor, was tested in fawn-hooded and monocrotaline rats. MEASUREMENTS AND MAIN RESULTS: We demonstrated that, in response to stress, HSP90 preferentially accumulates in PAH-PASMC mitochondria (dual immunostaining, immunoblot, and immunogold electron microscopy) to ensure cell survival by preserving mitochondrial DNA integrity and bioenergetic functions. Whereas cytosolic HSP90 inhibition displays a lack of absolute specificity for PAH-PASMCs, Gamitrinib decreased mitochondrial DNA content and repair capacity and bioenergetic functions, thus repressing PAH-PASMC proliferation (Ki67 labeling) and resistance to apoptosis (Annexin V assay) without affecting control cells. In vivo, Gamitrinib improves PAH in two experimental rat models (monocrotaline and fawn-hooded rat). CONCLUSIONS: Our data show for the first time that accumulation of mtHSP90 is a feature of PAH-PASMCs and a key regulator of mitochondrial homeostasis contributing to vascular remodeling in PAH.

PI3K therapy reprograms mitochondrial trafficking to fuel tumor cell invasion.

Molecular therapies are hallmarks of "personalized" medicine, but how tumors adapt to these agents is not well-understood. Here we show that small-molecule inhibitors of phosphatidylinositol 3-kinase (PI3K) currently in the clinic induce global transcriptional reprogramming in tumors, with activation of growth factor receptors, (re)phosphorylation of Akt and mammalian target of rapamycin (mTOR), and increased tumor cell motility and invasion. This response involves redistribution of energetically active mitochondria to the cortical cytoskeleton, where they support membrane dynamics, turnover of focal adhesion complexes, and random cell motility. Blocking oxidative phosphorylation prevents adaptive mitochondrial trafficking, impairs membrane dynamics, and suppresses tumor cell invasion. Therefore, "spatiotemporal" mitochondrial respiration adaptively induced by PI3K therapy fuels tumor cell invasion, and may provide an important antimetastatic target.

Timing and placement of cattle manure and/or gliricidia affects cotton and sunflower nutrient accumulation and biomass productivity.

Organic fertilizers are a viable alternative to increase oilseed productivity in family agriculture systems. The study aimed to evaluate the effects of timing and placement of cattle manure and/or gliricidia (Gliricidia sepium Jacq. Walp) prunings on cotton (Gossipium hirsutum L.) and sunflower (Helianthus annuus L.) nutrient accumulation and biomass productivity. Experiments were carried out in 2010 and 2011 in Taperoá, Paraíba, Brazil. The organic fertilization treatments were: GI - gliricidia incorporated before planting; GS - gliricidia applied on surface 45 days after planting (DAP); MI + GI - manure and gliricidia incorporated before planting; MI + GS - manure incorporated before planting and gliricídia applied on the surface 45 DAP; MI - manure incorporated before planting; and T - with no organic fertilization. In 2010, treatment MI + GS increased N, P, and K accumulation in cotton (12 and 7 kg ha-1) as well as in sunflower (20 and 29 kg ha-1). In 2011, GI and GS treatments resulted in higher N, P, K accumulations in both crops. The highest cotton productivity in 2010 was obtained with MI + GS treatment (198 kg ha-1) and in 2011 with GS treatment (594 kg ha-1). For sunflower, MI + GS treatment yielded the highest productivity in 2010 (466 kg ha-1) and GI treatment in 2011 (3542 kg ha-1). GI and MI + GS treatments increased total biomass productivity for cotton and sunflower. The treatment that combined both cattle manure incorporated into the soil before planting and gliricidia applied on the surface 45 days after planting was the most viable management strategy.