Tumor hypoxic microenvironment causes hypoxia inducible factor 1 alpha (HIF-1α) activation and necrosis with alarmins release. Importantly, HIF-1α also controls the expression of alarmin receptors in tumor cells that can bind to and be activated by alarmins. Human tumor tissues possess 1–2% of cancer stem cells (CSCs) residing in hypoxic niches and responsible for the metastatic potential of tumors. Our hypothesis is that hypoxic CSCs express alarmin receptors that can bind alarmins released during necrosis, an event favoring CSCs migration. To investigate this aspect, glioblastoma stem-like cell (GSC) lines were kept under hypoxia to determine the expression of hypoxic markers as well as receptor for advanced glycation end products (RAGE). The presence of necrotic extracts increased migration, invasion and cellular adhesion. Importantly, HIF-1α inhibition by digoxin or acriflavine prevented the response of GSCs to hypoxia alone or plus necrotic extracts. In vivo, GSCs injected in one brain hemisphere of NOD/SCID mice were induced to migrate to the other one in which a necrotic extract was previously injected. In conclusion, our results show that hypoxia is important not only for GSCs maintenance but also for guiding their response to external necrosis. Inhibition of hypoxic pathway may therefore represent a target for preventing brain invasion by glioblastoma stem cells (GSCs).
Pulmonary alveolar microlithiasis (PAM) is a rare disease of unknown etiology, characterized by the presence of calcific concretions in the alveolar spaces. A familial occurrence is frequently found so that an inherited trait is thought to be involved. The chest X-ray is characterized by a 'sandstrom' picture while the clinical state undergoes to a slow and progressive impairment resulting in respiratory failure at the end stage. We have reviewed the Italian literature of the past 50 years detecting 48 case-reports of PAM (19 males and 29 females). Only 20 out of them were documented in international journals. A familial occurrence of 43.7% was found and 18 patients were under age fifteen. There was a prevalence in the female sex (60.4%) and in the second decade of life. Chest X-ray was the most important tool to diagnose PAM revealing the characteristic picture in all patient. Bronchoalveolar lavage (BAL) and open lung biopsy respectively show the characteristic calcospherites in the recovered fluid (BALF) and in the alveolar spaces. About 300 cases of PAM are reported in the international literature. We believe these data are probably underestimated because many case-reports are not published in international literature.
During the past decades, several discoveries have established the role of epigenetic modifications and cellular microenvironment in tumor growth and progression. One of the main representatives concerning epigenetic modification is the polycomb group (PcG). It is composed of different highly conserved epigenetic effector proteins preserving, through several post-translational modifications of histones, the silenced state of the genes implicated in a wide range of central biological events such as development, stem cell formation, and tumor progression. Proteins of the PcG can be divided in polycomb repressive complexes (PRCs): PRC1 and PRC2. In particular, enhancer of zeste homolog 2 (EZH2), the catalytic core subunit of PRC2, acts as an epigenetic silencer of many tumor suppressor genes through the trimethylation of lysine 27 on histone H3, an essential binding site for DNA methyl transferases and histone deacetylases. A growing number of data suggests that overexpression of EZH2 associates with progression and poor outcome in a large number of cancer cases. Hypoxia inducible factor (HIF) is an important transcription factor involved in modulating cellular response to the microenvironment by promoting and regulating tumor development such as angiogenesis, inflammation, metabolic reprogramming, invasion, and metastatic fate. The HIF complex is represented by different subunits (α and β) acting together and promoting the expression of vascular endothelial growth factor (VEGF), hexokinase II (HKII), receptor for advanced glycation end products (RAGE), carbonic anhydrase (CA), etc., after binding to the hypoxia-response element (HRE) binding site on the DNA. In this review, we will try to connect these two players by detailing the following: (i) the activity and influence of these two important regulators of cancer progression in particular for what concerns pediatric tumors, (ii) the possible correlation between them, and (iii) the feasibility and efficiency to contrast them using several inhibitors.
Objective: Information is scanty on the patterns and settings of electronic cigarette use and on its possible adverse events. To fill the knowledge gap on these issues, we conducted a survey among ever-smokers attending smoking cessation services (SCS) in Italy. Methods: In 2016–2018, we enrolled 395 ever-smokers aged ⩾18 years who were current or former electronic cigarette users in 12 SCS from northern, central, and southern Italy. Results: In all, 12.4% of ever smokers were regular, 9.4% occasional, and 78.2% past users of electronic cigarettes. Of all users, 93.8% consumed electronic cigarettes with nicotine, 95.9% used refillable devices, and 76.6% purchased electronic cigarette devices or liquids in vape shops. The mean duration of use was 3.7 months and the mean number of puffs per day was 86. Among users, 71.5% used electronic cigarettes in at least 1 smoke-free indoor environment, 53.7% in workplaces, 49.5% in restaurants and bars, 33.5% in train/metro stations or airports, and 18.4% in public transports. The use of electronic cigarettes in smoke-free environments significantly decreased with age and increased with duration of use and nicotine dependence. In our sample, 47.1% reported at least 1 adverse event attributable to electronic cigarette use: 19.5% dry cough, 12.0% dry mouth, 7.6% throat or mouth irritation, and 6.8% sore throat. Conclusion: In Italy, most conventional cigarette smokers use electronic cigarettes where smoking conventional cigarettes is prohibited. About half of users reported 1 or more symptoms attributable to electronic cigarettes, despite the relatively short duration of use.
The presence of anti-zona pellucida antibodies in the follicular fluid of 11 women who underwent in-vitro fertilization (IVF) and embryo transfer was analysed. Only infertile couples with tubal or unexplained pathologies were included in our study, which was aimed at investigating the relationship between anti-zona pellucida antibodies in follicular fluid and failed fertilization. Whether or not these antibodies were present in some or all follicles in the same patient was also investigated. Out of 55 follicular fluids analysed, 36.3% were positive to the test and no fertilization was observed in oocytes from these follicles, while 63.6% were negative, and the oocyte fertilization rate associated with these was 51.4%. The presence of anti-zona pellucida antibodies was positively correlated with the degree of fertilization failure (P < 0.001 chi 2 test).
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