Autophagy maintains cellular homeostasis by degrading harmful or unnecessary intracellular components. How the autophagy response is induced rapidly and transiently remains largely unknown. We report that the E3 ubiquitin ligases Cullin-5 and Cullin-4 regulate the onset and termination of autophagy, respectively, by dynamically interacting with AMBRA1, a regulator of autophagy. Under normal conditions, Cullin-4 binding to AMBRA1 limits its protein abundance. Autophagy stimuli promote AMBRA1 stabilization by causing ULK1-dependent Cullin-4 release. Notably, Cullin-4/AMBRA1 dissociation is transient, and the re-established interaction triggers AMBRA1 degradation, terminating the autophagy response. Moreover, Cullin-4 inhibits the interaction between AMBRA1 and another Cullin E3 ligase. Indeed, upon Cullin-4 dissociation, AMBRA1 binds and inhibits Cullin-5, thus promoting the accumulation of the mTOR inhibitor DEPTOR. Through DEPTOR stabilization, AMBRA1 establishes a feedback loop that ensures the rapid onset of autophagy by enhancing mTOR inactivation. Our findings show that Cullin-mediated degradation of autophagy regulators temporally controls the autophagy response.

A record-linkage study was carried out between the Italian AIDS Registry and 24 Italian cancer registries to compare cancer excess among persons with HIV/AIDS (PWHA) before and after the introduction of highly active antiretroviral therapy (HAART) in 1996. Standardised incidence ratios (SIR) were computed in 21951 AIDS cases aged 16 -69 years reported between 1986 and 2005. Of 101 669 person-years available, 45 026 were after 1996. SIR for Kaposi sarcoma (KS) and non-Hodgkin lymphoma greatly decreased in 1997 -2004 compared with 1986 -1996, but high SIRs for KS persisted in the increasingly large fraction of PWHA who had an interval of o1 year between first HIV-positive test and AIDS diagnosis. A significant excess of liver cancer (SIR ¼ 6.4) emerged in 1997 -2004, whereas the SIRs for cancer of the cervix (41.5), anus (44.0), lung (4.1), brain (3.2), skin (non-melanoma, 1.8), Hodgkin lymphoma (20.7), myeloma (3.9), and non-AIDS-defining cancers (2.2) were similarly elevated in the two periods. The excess of some potentially preventable cancers in PWHA suggests that HAART use must be accompanied by cancer-prevention strategies, notably antismoking and cervical cancer screening programmes. Improvements in the timely identification of HIV-positive individuals are also a priority in Italy to avoid the adverse consequences of delayed HAART use.

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OBJECTIVES:A growing body of evidence indicates that patients with sessile serrated adenoma/polyp (SSA/P) and traditional serrated adenoma (TSA) are at risk for subsequent malignancy. Despite increasing knowledge on histological categorization of serrated polyps (SPs) data are lacking on the actual prevalence and the association of each SP subtype with advanced colorectal neoplasia.METHODS:We prospectively determined the prevalence of different SP subtypes and evaluate the association with synchronous advanced neoplasia in asymptomatic average-risk subjects undergoing first-time colonoscopy. All retrieved polyps were examined by two independent pathologists. Serrated lesions were classified into hyperplastic polyps (HP), SSA/P (without and with cytological dysplasia, SSA/P/DIS), and TSA, and were screened for BRAF and K-ras mutations.RESULTS:Among 258 polyps detected in 985 subjects, the proportion of SSA/P and TSA was 8.9% and 1.9% with an overall prevalence of 2.3% and 0.6%, respectively. SSA/Ps were small without significant difference in their location between proximal and distal colon; TSA were predominantly left-sided. BRAF mutation was common in SSA/Ps and K-ras mutation was present in all TSA. Independent predictors of advanced neoplasia were male sex (odds ratio (OR)=2.0, 95% confidence interval (CI) 1.0–4.0), increasing age (OR=4.5, 95% CI 1.5–13.4 for 50–69 years and OR=9.9, 95% CI 3.1–31.5 for >70 years), current smoking (OR=2.0, 95% CI 1.3–6.8), >3 tubular adenoma (OR=3.6, 95% CI 1.9–6.4), and SSA/P (OR=6.0, 95% CI 1.9–19.5).CONCLUSIONS:The substantial prevalence of BRAF-mutated SSA/P and the independent association with synchronous advanced colorectal neoplasia in asymptomatic average-risk subjects support the overall impact of the serrated pathway on colorectal cancer (CRC) risk in general population. The endoscopic characteristics of SSA/P emphasize the need of high-quality colonoscopy as a key factor for an effective CRC screening program.

Since December 2019, SARS-CoV-2 infection has been still rapidly spreading, resulting in a pandemic, followed by an increasing number of cases in countries throughout the world. The severity of the disease depends on the patient’s overall medical condition but no appropriate markers are available to establish the prognosis of the patients. We performed a 16S rRNA gene sequencing, revealing an altered composition of the nasal/oropharyngeal (NOP) microbiota in 21 patients affected by COVID-19, paucisymptomatic or in an Intensive Care Unit (ICU), as compared to 10 controls negative for COVID-19 or eight affected by a different Human Coronavirus (HKU, NL63 and OC43). A significant decrease in Chao1 index was observed when patients affected by COVID-19 (in ICU) were compared to paucisymptomatic. Furthermore, patients who were in ICU, paucisymptomatic or affected by other Coronaviruses all displayed a decrease in the Chao1 index when compared to controls, while Shannon index significantly decreased only in patients under ICU as compared to controls and paucisymptomatic patients. At the phylum level, Deinococcus-Thermus was present only in controls as compared to SARS-CoV-2 patients admitted to ICU, paucisymptomatic or affected by other coronaviruses. Candidatus Saccharibacteria (formerly known as TM7) was strongly increased in negative controls and SARS-CoV-2 paucisymptomatic patients as compared to SARS-CoV-2 ICU patients. Other modifications were observed at a lower taxonomy level. Complete depletion of Bifidobacterium and Clostridium was exclusively observed in ICU SARS-CoV-2 patients, which was the only group characterized by the presence of Salmonella, Scardovia, Serratia and Pectobacteriaceae. In conclusion, our preliminary results showed that nasal/oropharyngeal microbiota profiles of patients affected with SARS-CoV-2 may provide valuable information in order to facilitate the stratification of patients and may open the way to new interventional strategies in order to ameliorate the outcome of the patients.

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Before the introduction of HAART, HIV-associated neurocognitive impairment (NCI) was recognized as an independent risk factor for death. Since 1996, we conducted a prospective study to assess whether NCI still represents a negative prognostic factor for mortality. Patients were administered measures of neurocognitive function (a battery of 17 neuropsychological tests), clinical and neurological evaluation, laboratory testing, and brain imaging studies. Among the 412 enrolled patients, 224 (54.4%) were neurocognitively impaired and 188 (45.6%) were neurocognitively unimpaired. A durable virological suppression under highly active antiretroviral therapy (HAART) was achieved by 63.3% of unimpaired patients and by 49.6% of impaired patients (p = 0.007). Overall, 47 deaths were recorded, 38 among impaired and 9 among unimpaired patients. At 84 months, the estimated survival proportions in impaired and unimpaired patients were 68.5% and 84.9%, respectively (p < 0.001). At univariate analysis the virological response to HAART was the variable most strongly associated with survival, since patients with virological failure had a nearly 10-fold increased risk of death than those with durable virological suppression (HR = 9.9, 95% CI: 3.9-25.0). After stratification for virological response to HAART, an increased risk of death for neurocognitively impaired patients was seen only among the 182 patients with virological failure (HR: 2.9, 95% CI: 1.2-7.1), while the survival probability of the 230 patients with durable virological suppression was not affected by neurocognitive impairment (p = 0.89). Our results highlight the clinical relevance of HIV-related central nervous system (CNS) involvement in the HAART era, and raise concerns regarding the clinical relevance of CNS involvement as potent antiretroviral therapies become less effective.

BackgroundTo investigate perceptions and attitude to prescribe Pre-Exposure Prophylaxis (PrEP) among HIV specialists.MethodsA questionnaire developed through a Focus Group and literature review was administered to a convenience sample of HIV specialists during educational courses in two Regions and an online survey in February-May 2012. Participants were classified as having a positive or negative attitude according to their willingness to prescribe PrEP. Demographic and working information, experience with HIV-infected patients, information and provision of antiretrovirals to uninfected persons, self-reported knowledge, perceptions and concerns regarding PrEP were assessed. The association between a different attitude towards PrEP prescription and selected characteristics was assessed through univariate and multivariate regression analysis.ResultsOf 311 specialists, 70% would prescribe PrEP, mainly to serodiscordant partners (64%) but also to people at ongoing, high risk of HIV infection (56%); 66% advocated public support of costs. A negative attitude towards PrEP was significantly associated with lack of provision of information on, and prescription of, antiretroviral post-exposure prophylaxis; specialists with a negative attitude believed behavioural interventions to be more effective than PrEP and were more concerned about toxicity. Overall, 90% of specialists disagreed regarding a lack of time for engaging in prevention counselling and PrEP monitoring; 79% would welcome formal guidelines, while those with a negative attitude did not consider this advisable.ConclusionsAlthough conflicting attitudes appear evident, most specialists seem to be willing, with guidance from normative bodies, to promote PrEP within multiple prevention strategies among vulnerable populations. More scientific evidence regarding effectiveness could overcome resistance.