Cooperative pro-tumorigenic adaptation to oncogenic RAS through epithelial-to-mesenchymal plasticity

In breast cancers, aberrant activation of the RAS/MAPK pathway is strongly associated with mesenchymal features and stemness traits, suggesting an interplay between this mitogenic signaling pathway and epithelial-to-mesenchymal plasticity (EMP). By using inducible models of human mammary epithelial cells, we demonstrate herein that the oncogenic activation of RAS promotes ZEB1-dependent EMP, which is necessary for malignant transformation. Notably, EMP is triggered by the secretion of pro-inflammatory cytokines from neighboring RAS-activated senescent cells, with a prominent role for IL-6 and IL-1α. Our data contrast with the common view of cellular senescence as a tumor-suppressive mechanism and EMP as a process promoting late stages of tumor progression in response to signals from the tumor microenvironment. We highlighted here a pro-tumorigenic cooperation of RAS-activated mammary epithelial cells, which leverages on oncogene-induced senescence and EMP to trigger cellular reprogramming and malignant transformation.

Human molecular chaperones share with SARS-CoV-2 antigenic epitopes potentially capable of eliciting autoimmunity against endothelial cells: possible role of molecular mimicry in COVID-19

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2), the cause of COVID-19 disease, has the potential to elicit autoimmunity because mimicry of human molecular chaperones by viral proteins. We compared viral proteins with human molecular chaperones, many of which are heat shock proteins, to determine if they share amino acid-sequence segments with immunogenic-antigenic potential, which can elicit cross-reactive antibodies and effector immune cells with the capacity to damage-destroy human cells by a mechanism of autoimmunity. We identified the chaperones that can putatively participate in molecular mimicry phenomena after SARS-CoV-2 infection, focusing on those for which endothelial cell plasma-cell membrane localization has already been demonstrated. We also postulate that post-translational modifications, induced by physical (shear) and chemical (metabolic) stress caused respectively by the risk factors hypertension and diabetes, might have a role in determining plasma-cell membrane localization and, in turn, autoimmune-induced endothelial damage.

Genome-Wide Analysis of DNA Methylation and Acute Coronary Syndrome

Rationale:

Acute coronary syndrome (ACS) is a leading cause of death worldwide. Immune functions play a vital role in ACS development; however, whether epigenetic modulation contributes to the regulation of blood immune cells in this disease has not been investigated.

Objective:

We conducted an epigenome-wide analysis with circulating immune cells to identify differentially methylated genes in ACS.

Methods and Results:

We examined genome-wide methylation of whole blood in 102 ACS patients and 101 controls using HumanMethylation450 array, and externally replicated significant discoveries in 100 patients and 102 controls. For the replicated loci, we further analyzed their association with ACS in 6 purified leukocyte subsets, their correlation with the expressions of annotated genes, and their association with cardiovascular traits/risk factors. We found novel and reproducible association of ACS with blood methylation at 47 cytosine-phosphoguanine sites (discovery: false discovery rate <0.005; replication: Bonferroni corrected P <0.05). The association of methylation levels at these cytosine-phosphoguanine sites with ACS was further validated in at least 1 of the 6 leukocyte subsets, with predominant contributions from CD8 + T cells, CD4 + T cells, and B cells. Blood methylation of 26 replicated cytosine-phosphoguanine sites showed significant correlation with expressions of annotated genes (including IL6R , FASLG , and CCL18 ; P <5.9×10 −4 ), and differential gene expression in case versus controls corroborated the observed differential methylation. The replicated loci suggested a role in ACS-relevant functions including chemotaxis, coronary thrombosis, and T-cell–mediated cytotoxicity. Functional analysis using the top ACS-associated methylation loci in purified T and B cells revealed vital pathways related to atherogenic signaling and adaptive immune response. Furthermore, we observed a significant enrichment of the replicated cytosine-phosphoguanine sites associated with smoking and low-density lipoprotein cholesterol ( P enrichment ≤1×10 −5 ).

Conclusions:

Our study identified novel blood methylation alterations associated with ACS and provided potential clinical biomarkers and therapeutic targets. Our results may suggest that immune signaling and cellular functions might be regulated at an epigenetic level in ACS.

Sleep Duration and Midday Napping with 5-Year Incidence and Reversion of Metabolic Syndrome in Middle-Aged and Older Chinese

STUDY OBJECTIVES

Prospective evidence on the association of sleep duration and midday napping with metabolic syndrome (MetS) is limited. We aimed to examine the associations of sleep duration and midday napping with risk of incidence and reversion of MetS and its components among a middle-aged and older Chinese population.

METHODS

We included 14,399 subjects from the Dongfeng-Tongji (DFTJ) Cohort Study (2008-2013) who were free of coronary heart disease, stroke, and cancer at baseline. Baseline data were obtained by questionnaires and health examinations. Odds ratios (ORs) and 95% confidence interval (CI) were derived from multivariate logistic regression models.

RESULTS

After controlling for potential covariates, longer sleep duration (≥ 9 h) was associated with a higher risk of MetS incidence (OR, 1.29; 95% CI, 1.08-1.55) and lower reversion of MetS (OR, 0.80; 95% CI, 0.66-0.96) compared with sleep duration of 7 to < 8 h; whereas shorter sleep duration (< 6 h) was not related to incidence or reversion of MetS. For midday napping, subjects with longer napping (≥ 90 min) was also associated with a higher risk of MetS incidence and a lower risk of MetS reversion compared with those with napping of 1 to < 30 min (OR, 1.48; 95% CI, 1.05-2.10 and OR, 0.70; 95% CI, 0.52-0.94, respectively). Significance for incidence or reversion of certain MetS components remained in shorter and longer sleepers but disappeared across napping categories.

CONCLUSIONS

Both longer sleep duration and longer midday napping were potential risk factors for MetS incidence, and concurrently exert adverse effects on MetS reversion.

Identification of circulating microRNAs during the liver neoplastic process in a murine model of hereditary tyrosinemia type 1

Hereditary tyrosinemia type 1 (HT1) is a severe inborn error of metabolism, impacting the tyrosine catabolic pathway with a high incidence of hepatocellular carcinoma (HCC). Using a HT1 murine model, we investigated the changes in profiles of circulating and hepatic miRNAs. The aim was to determine if plasma miRNAs could be used as non-invasive markers of liver damage in HT1 progression. Plasma and liver miRNAome was determined by deep sequencing after HT1 phenotype was induced. Sequencing analysis revealed deregulation of several miRNAs including let-7/miR-98 family, miR-21 and miR-148a, during manifestation of liver pathology. Three miRNAs (miR-98, miR-200b, miR-409) presenting the highest plasmatic variations among miRNAs found in both plasma and liver and with >1000 reads in at least one plasma sample, were further validated by RT-qPCR. Two of these miRNAs have protein targets involved in HT1 and significant changes in their circulating levels are detectable prior an increase in protein expression of alpha-fetoprotein, the current biomarker for HCC diagnosis. Future assessment of these miRNAs in HT1 patients and their association with liver neoplastic lesions might designate these molecules as potential biomarkers for monitoring HT1 damage progression, improving diagnosis for early HCC detection and the design of novel therapeutic targets.

Clinical management of critically ill patients with Cushing's disease due to ACTH-secreting pituitary macroadenomas: effectiveness of presurgical treatment with pasireotide

The management of critically ill Cushing's disease (CD) patients is extremely challenging. Pasireotide is indicated for the treatment of CD patients when pituitary surgery is unfeasible or has not been curative, but no data are available about the use of this drug as pre-operative treatment in critically ill patients. We report the effects of presurgical pasireotide therapy in CD patients in whom hypercortisolism caused life-threatening hypokalemia, alkalosis, and cardio-respiratory complications precluding surgical approach. Clinical, biochemical, and radiological data of two critically ill patients with ACTH-secreting pituitary macroadenoma, before and during first-line presurgical pasireotide treatment (600 μg s.c. bid). During the first 21 days of treatment, pasireotide therapy induced a rapid, partial decrease of plasma ACTH, serum cortisol, and urinary free cortisol levels, with the consequent normalization of serum potassium concentration and arterial blood gases parameters, in both the patients. They did not experience unmanageable side effects and underwent endoscopic transsphenoidal surgery after 4 weeks of effective treatment. Pre-operative MRI evaluation did not show pituitary tumor shrinkage. Surgical cure of CD was obtained in the first patient, while debulking allowed the pharmacological control of hypercortisolism in the second case. We suggest that pasireotide can induce a rapid improvement of clinical and metabolic conditions in critically ill CD patients in whom surgical approach is considered hazardous and need to be delayed.

Molecular changes associated with chronic liver damage and neoplastic lesions in a murine model of hereditary tyrosinemia type 1

Hereditary tyrosinemia type 1 (HT1) is the most severe inherited metabolic disease of the tyrosine catabolic pathway, with a progressive hepatic and renal injury and a fatal outcome if untreated. Toxic metabolites accumulating in HT1 have been shown to elicit endoplasmic reticulum (ER) stress response, and to induce chromosomal instability, cell cycle arrest and apoptosis perturbation. Although many studies have concentrated on elucidating these events, the molecular pathways responsible for development of hepatocellular carcinoma (HCC) still remain unclear. In this study the fah knockout murine model (fah(-/-)) was used to investigate the cellular signaling implicated in the pathogenesis of HT1. Fah(-/-) mice were subjected to drug therapy discontinuation (Nitisinone withdrawal), and livers were analyzed at different stages of the disease. Monitoring of mice revealed an increasing degeneration of the overall physiological conditions following drug withdrawal. Histological analysis unveiled diffuse hepatocellular damage, steatosis, oval-like cells proliferation and development of liver cell adenomas. Immunoblotting results revealed a progressive and chronic activation of stress pathways related to cell survival and proliferation, including several stress regulators such as Nrf2, eIF2α, CHOP, HO-1, and some members of the MAPK signaling cascade. Impairment of stress defensive mechanisms was also shown by microarray analysis in fah(-/-) mice following prolonged therapy interruption. These results suggest that a sustained activation of stress pathways in the chronic HT1 progression might play a central role in exacerbating liver degeneration.

Hsp60, a novel target for antitumor therapy: structure-function features and prospective drugs design

Heat shock protein 60 kDa (Hsp60) is a chaperone classically believed to be involved in assisting the correct folding of other mitochondrial proteins. Hsp60 also plays a role in cytoprotection against cell stressors, displaying for example, antiapoptotic potential. Despite the plethora of studies devoted to the mechanism of Hsp60's function, especially in prokaryotes, fundamental issues still remain unexplored, including the definition of its role in cancer. Key questions still unanswered pertain to the differences in structure-function features that might exist between the well-studied prokaryotic GroEL and the largely unexplored eukaryotic Hsp60 proteins. In this article we discuss these differences in sequence, structure, and roles of Hsp60, focusing on the human ortholog with the view of devising compounds to block its ability to favour tumor-cell growth and survival. Compounds currently known to directly or indirectly affect Hsp60 functions, such as protein folding, HIF-1α accumulation, or Hsp60-induced cell proliferation, are discussed along with strategies that might prove effective for developing Hsp60-targeting drugs for anticancer therapy.

Synthesis and biological activities of a new class of heat shock protein 90 inhibitors, designed by energy-based pharmacophore virtual screening

The design through energy-based pharmacophore virtual screening has led to aminocyanopyridine derivatives as efficacious new inhibitors of Hsp90. The synthesized compounds showed a good affinity for the Hsp90 ATP binding site in the competitive binding assay. Moreover, they showed an excellent antiproliferative activity against a large number of human tumor cell lines. Further biological studies on the derivative with the higher EC50 confirmed its specific influence on the cellular pathways involving Hsp90.

Chaperonopathies and chaperonotherapy. Hsp60 as therapeutic target in cancer: potential benefits and risks

In this minireview we focus on Hsp60 as a target for anticancer therapy. We discuss the new concepts of chaperonopathies and chaperonotherapy and present information on Hsp60 localization in the cell membrane of human tumor cells. We describe novel mechanisms for Hsp60 reaching the extracellular environment that involve membrane-associated stages, as well as data on anti-Hsp60 antibodies found in human sera, both in normal subjects and patients affected by autoimmune diseases. Finally, we discuss possible therapeutic applications of anti-Hsp60 antibodies in cancer treatment, evaluating also side effects on non-tumor cells. In conclusion, the way for investigating Hsp60-targeted anti-tumor therapy is open, at least for those tumors that express Hsp60 on its surface and/or secrete it outside the cell, as is the search for the molecular mechanisms involved in Hsp60 translocation from cytosol to cell membrane: elucidation of this mechanism will greatly facilitate the optimization of chaperonotherapy centered on Hsp60 with anti-tumor efficacy and minimal side effects.

Classification of morphological features extracted from intracranial pressure recordings in the diagnosis of Normal Pressure Hydrocephalus (NPH)

The intracranial pressure (ICP) monitoring is a common procedure in neuro-intensive care for pathologies such traumatic brain injuries or hemorrhages, but also for chronic ones as the Normal Pressure Hydrocephalus (NPH). The only available treatment for NPH is the surgical implantation of a shunt with the aim of routing cerebrospinal fluid (CSF) away from the brain to another part of the body. In this study, using the classification software WEKA, an intensive investigation of ICP signals has been conducted. In particular we studied 14 ICP recordings of different patients who underwent an infusion test, with the aim of investigating the presence of NPH through the ICP recording. More precisely, 20 morphological features are extracted from the ICP pulsed wave, the trend have been computed and, for each one, 9 statistical functions determined. The 180 features have been selected and passed for the classification. The results obtained shows how, among the 14 patients, a number of 12 out of 14 (85.7%) have been correctly classified, looking at just 3 features. In particular 8 out of 9 not-NPH-affected patients were correctly identified (88.89%) while 4 out of 5 NPH-affected patients were correctly identified (80%).

Analysis of intracranial pressure recordings: comparison of PCA and signal averaging based filtering methods and signal period estimation

Intracranial pressure monitoring is a common used approach for neuro-intensive care in cases of brain damages and injuries or to investigate chronic pathologies. Several types of noises and artifacts normally contaminate ICP recordings. They can be sorted in 2 classes, i.e. high-frequency noises (due to measurement and amplifier devices or electricity supply presence) and low-frequency noises (due to unwanted patient's movement, speeches, coughing during the recording and quantization noise). Thus, deep investigations on ICP components aimed to extract features from ICP signal, require a denoised signal. For this reason the authors have addressed a study upon the most common filtering techniques. On each ICP recording we have performed 4 configurations of filters, which involve the use of a FIR filter together with Signal Averaging filters or PCA based filters. Next step is period estimation for absolute minima detection. The results obtained by the algorithm for automatic ICP marking are compared to those ones obtained from manual marking (peaks are manually identified and annotated by a brain surgeon). The procedure is repeated varying the filters sliding window size to minimize the mean square error. The results show how the configurations FIR filter + Signal averaging provides smaller mean squared error (MSE=118.84[sample(2)]) than the others 3 configurations FIR filter + PCA filter based (MSE=135.29-147.15[sample(2)]).

A preliminary study for investigating idiopatic normal pressure hydrocephalus by means of statistical parameters classification of intracranial pressure recordings

The objective of this study is to investigate Id-iopatic Normal Pressure Hydrocephalus (INPH) through a multidimensional and multiparameter analysis of statistical data obtained from accurate analysis of Intracranial Pressure (ICP) recordings. Such a study could permit to detect new factors, correlated with therapeutic response, which are able to validate a predicting significance for infusion test. The algorithm developed by the authors computes 13 ICP parameter trends on each of the recording, afterward 9 statistical information from each trend is determined. All data are transferred to the datamining software WEKA. According to the exploited feature-selection techniques, the WEKA has revealed that the most significant statistical parameter is the maximum of Single-Wave-Amplitude: setting a 27 mmHg threshold leads to over 90% of correct classification.

Protective effects of moderate hypothermia on behavioral deficits but not necrotic cavitation following cortical impact injury in the rat

A number of experimental studies have reported that moderate hypothermia can produce significant protection against behavioral deficits and/or morphopathological alterations following traumatic brain injury; a Phase 3 clinical trial is currently examining the therapeutic potential for moderate hypothermia (32 degrees C) to improve outcome following severe traumatic brain injury in humans. The current study examined whether hypothermia (32 degrees C) provided behavioral protection following experimental cortical impact injury. The extent of focal cortical contusion was also examined in the same rats. A total of 30 male Sprague-Dawley rats were trained on beam balance and beam walking tasks prior to injury. Under isoflurane anesthesia, cortical impact was produced on the right parietal cortex of 20 rats. Ten rats underwent all surgical procedures but were not impacted (sham-injured rats). Ten of the injured rats were cooled to 32 degrees C (measured in temporalis muscle) beginning 5 min postinjury, maintained for 2 h and rewarmed slowly for 1 h. In the other 10 injured rats, normothermic temperatures (37.5 degrees C) were maintained for the same duration. Beam balance and beam walking performance was assessed daily for 5 days following injury. At 11 days postinjury, rats were assessed for 5 days on acquisition of the Morris water maze task. Following behavioral assessments, rats were perfused and the brain removed. Coronal sections were cut through the site of cortical impact injury and stained with hematoxylin and eosin. Hypothermic treatment resulted in significantly less beam balance and beam walking deficits than observed in normothermic rats. Hypothermia also significantly attenuated spatial memory performance deficits. Quantitative morphometric analyses failed to detect any significant differences in volumes of necrotic tissue cavitation in cortices of hypothermic and normothermic rats. Hypothermic treatment also had no effect on volumes of dorsal hippocampal tissue or numbers of cells in CA1 or CA3 regions of the hippocampus. These data suggest that hypothermia, consistent with the reports of others, can produce significant behavioral protection following cortical impact injury that is not necessarily correlated with changes in focal cortical necrosis within the first 15 days following injury.