Pharmacological activation of SIRT6 triggers lethal autophagy in human cancer cells

Sirtuin 6 (SIRT6) is a member of the NAD+-dependent class III deacetylase sirtuin family, which plays a key role in cancer by controlling transcription, genome stability, telomere integrity, DNA repair, and autophagy. Here we analyzed the molecular and biological effects of UBCS039, the first synthetic SIRT6 activator. Our data demonstrated that UBCS039 induced a time-dependent activation of autophagy in several human tumor cell lines, as evaluated by increased content of the lipidated form of LC3B by western blot and of autophagosomal puncta by microscopy analysis of GFP-LC3. UBCS039-mediated activation of autophagy was strictly dependent on SIRT6 deacetylating activity since the catalytic mutant H133Y failed to activate autophagy. At the molecular level, SIRT6-mediated autophagy was triggered by an increase of ROS levels, which, in turn, resulted in the activation of the AMPK-ULK1-mTOR signaling pathway. Interestingly, antioxidants were able to completely counteract UBCS039-induced autophagy, suggesting that ROS burst had a key role in upstream events leading to autophagy commitment. Finally, sustained activation of SIRT6 resulted in autophagy-related cell death, a process that was markedly attenuated using either a pan caspases inhibitor (zVAD-fmk) or an autophagy inhibitor (CQ). Overall, our results identified UBCS039 as an efficient SIRT6 activator, thereby providing a proof of principle that modulation of the enzyme can influence therapeutic strategy by enhancing autophagy-dependent cell death

Trifunctionalized Naphthalene Diimides and Dimeric Analogues as G-Quadruplex-Targeting Anticancer Agents Selected by Affinity Chromatography

A focused library of newly designed monomeric and dimeric naphthalene diimides (NDIs) was analyzed in its ability to recognize specific G-quadruplex (G4) structures discriminating duplex DNA. The best G4 ligands—according to an affinity chromatography-based screening method named G4-CPG—were tested on human cancer and healthy cells, inducing DNA damage at telomeres, and in parallel, showing selective antiproliferative activity on HeLa cancer cells with IC50 values in the low nanomolar range. CD and fluorescence spectroscopy studies allowed detailed investigation of the interaction in solution with different G4 and duplex DNA models of the most promising NDI of the series, as determined by combining the biophysical and biological assays’ data

Burden and prevention of HPV. Knowledge, Practices and Attitude Assessment Among Pre-adolescents and their Parents in Italy

Despite infections due to HPV nowadays represent the most common sexually transmitted diseases worldwide with recognized effective and safe preventive strategies, knowledge, attitudes; however, awareness on HPV is considerably low. The present study has two main objectives: 1. To conduct a literature review to analyze the evolution of preventive tools, the complexity of the vaccine choice process, and the challenges posed by HPV vaccine hesitancy and refusal among pre-adolescents and their parents; 2. To assess knowledge, practices and attitudes toward HPV infection and vaccination in a sample of Italian pre-adolescents and their parents. The observational study was carried out through the use of two anonymous and self-administered pre- and post-intervention questionnaires dedicated to the target populations. Between the administrations of the pre- and post-intervention questionnaires, an educational intervention on ITV infection and related diseases, and prevention strategies was conducted. All participants demonstrated suboptimal knowledge and positive attitudes in the pre-intervention questionnaire. Higher levels of knowledge and attitudes were observed among pre-adolescents thatused social networks and had heard of sexually transmitted diseases at home/school/physician and from parents and also who had heard of HPV from General Practitioners, Gynecologists, family members and newspapers. A significant increase in HPV vaccination awareness was observed among pre-adolescents after the educational sessions. Health education programs aimed at increasing knowledge, attitudes and awareness on HPV are needed to implement the outcomes of HPV immunization programs, especially if supported by the physicians involved in counselling and recommendation processes

Group IV Phospholipase A2α Controls the Formation of Inter-Cisternal Continuities Involved in Intra-Golgi Transport

The enzyme phospholipase A2 (cPLA2α) is involved in the formation of intercisternal tubules that mediate transport of proteins within the Golgi complex

Change in Non-Motor Symptoms in Parkinson's Disease and Essential Tremor Patients: A One-year Follow-up Study

<p><strong>Background:&nbsp;</strong>Non‐motor symptoms (NMS) in Parkinson's disease (PD) differ from those in essential tremor (ET), even before a definitive diagnosis is made. It is not clear whether patient's knowledge of the diagnosis and treatment influence their subsequent reporting of NMS.</p><p><strong>Methods:&nbsp;</strong>1 year after a clinical and instrumental diagnosis, we compared the motor impairment (Movement Disorders Society (MDS)‐Unified Parkinson's Disease Rating Scale‐III) and non‐motor symptoms (NMSQuest) in PD (n = 31) and ET (n = 21) patients.</p><p><strong>Results:&nbsp;</strong>PD patients reported more NMS than did the ET patients (p = 0.002). When compared to their baseline report, at follow‐up, PD patients reported less nocturia (p = 0.02), sadness (p = 0.01), insomnia (p = 0.02), and restless legs (p = 0.04) and more nausea (p = 0.024), unexplained pain (p = 0.03), weight change (p = 0.009), and daytime sleepiness (p = 0.03). When compared to their baseline report, ET patients reported less loss of interest (p = 0.03), anxiety (p = 0.006), and insomnia (p = 0.02). Differences in reported weight change (p&lt;0.0001) and anxiety (p = 0.001) between PD and ET patients were related to pharmacological side effects or to a reduction in the ET individuals.</p><p><strong>&nbsp;</strong></p><p><strong>Discussion:&nbsp;</strong>The reporting of NMS is influenced by subjective factors, and might vary with the patient's knowledge of the diagnosis or the effectiveness of treatment.</p

Selective Targeting of Cancer-Related G-Quadruplex Structures by the Natural Compound Dicentrine

Aiming to identify highly effective and selective G-quadruplex ligands as anticancer candidates, five natural compounds were investigated here, i.e., the alkaloids Canadine, D-Glaucine and Dicentrine, as well as the flavonoids Deguelin and Millettone, selected as analogs of compounds previously identified as promising G-quadruplex-targeting ligands. A preliminary screening with the G-quadruplex on the Controlled Pore Glass assay proved that, among the investigated compounds, Dicentrine is the most effective ligand of telomeric and oncogenic G-quadruplexes, also showing good G-quadruplex vs. duplex selectivity. In-depth studies in solution demonstrated the ability of Dicentrine to thermally stabilize telomeric and oncogenic G-quadruplexes without affecting the control duplex. Interestingly, it showed higher affinity for the investigated G-quadruplex structures over the control duplex (Kb~106 vs. 105 M−1), with some preference for the telomeric over the oncogenic G-quadruplex model. Molecular dynamics simulations indicated that Dicentrine preferentially binds the G-quadruplex groove or the outer G-tetrad for the telomeric and oncogenic G-quadruplexes, respectively. Finally, biological assays proved that Dicentrine is highly effective in promoting potent and selective anticancer activity by inducing cell cycle arrest through apoptosis, preferentially targeting G-quadruplex structures localized at telomeres. Taken together, these data validate Dicentrine as a putative anticancer candidate drug selectively targeting cancer-related G-quadruplex structures

Tailoring a lead-like compound targeting multiple G-quadruplex structures

A focused library of analogs of a lead-like G-quadruplex (G4) targeting compound (4), sharing a furobenzoxazine naphthoquinone core and differing for the pendant groups on the N-atom of the oxazine ring, has been here analyzed with the aim of developing more potent and selective ligands. These molecules have been tested vs. topologically different G4s by the G4-CPG assay, an affinity chromatography-based method for screening putative G4 ligands. The obtained results showed that all these compounds were able to bind several G4 structures, both telomeric and extra-telomeric, thus behaving as multi-target ligands, and two of them fully discriminated G4 vs. duplex DNA. Biological assays proved that almost all the compounds produced effective DNA damage, showing marked antiproliferative effects on tumor cells in the low μM range. Combined analysis of the G4-CPG binding assays and biological data led us to focus on compound S4-5, proved to be less cytotoxic than the parent compound 4 on normal cells. An in-depth biophysical characterization of the binding of S4-5 to different G4s showed that the here identified ligand has higher affinity for the G4s and higher ability to discriminate G4 vs. duplex DNA than 4. Molecular docking studies, in agreement with the NMR data, suggest that S4-5 interacts with the accessible grooves of the target G4 structures, giving clues for its increased G4 vs. duplex selectivity