RNA-Binding protein HuR and the members of miR-200 family play an unconventional role in the regulation of c-Jun mRNA

Post-transcriptional gene regulation is a fundamental step for coordinating cellular response in a variety of processes. RNA-binding proteins (RBPs) and microRNAs (miRNAs) are the most important factors responsible for this regulation. Here we report that different components of the miR-200 family are involved in c-Jun mRNA regulation with the opposite effect. While miR-200b inhibits c-Jun protein production, miR-200a tends to increase the JUN amount through a stabilization of its mRNA. This action is dependent on the presence of the RBP HuR that binds the 3′UTR of c-Jun mRNA in a region including the mir-200a binding site. The position of the binding site is fundamental; by mutating this site, we demonstrate that the effect is not micro-RNA specific. These results indicate that miR-200a triggers a microRNA-mediated stabilization of c-Jun mRNA, promoting the binding of HuR with c-Jun mRNA. This is the first example of a positive regulation exerted by a microRNA on an important oncogene in proliferating cells

Rapid SARS-CoV-2 intra-host and within-household emergence of novel haplotypes

In February 2020, the municipality of Vo’, a small town near Padua (Italy) was quarantined due to the first coronavirus disease 19 (COVID-19)-related death detected in Italy. To investigate the viral prevalence and clinical features, the entire population was swab tested in two sequential surveys. Here we report the analysis of 87 viral genomes, which revealed that the unique ancestor haplotype introduced in Vo’ belongs to lineage B, carrying the mutations G11083T and G26144T. The viral sequences allowed us to investigate the viral evolution while being transmitted within and across households and the effectiveness of the non-pharmaceutical interventions implemented in Vo’. We report, for the first time, evidence that novel viral haplotypes can naturally arise intra-host within an interval as short as two weeks, in approximately 30% of the infected individuals, regardless of symptom severity or immune system deficiencies. Moreover, both phylogenetic and minimum spanning network analyses converge on the hypothesis that the viral sequences evolved from a unique common ancestor haplotype that was carried by an index case. The lockdown extinguished both the viral spread and the emergence of new variant

The importance of a taste. A comparative study on wild food plant consumption in twenty-one local communities in Italy

A comparative food ethnobotanical study was carried out in twenty-one local communities in Italy, fourteen of which were located in Northern Italy, one in Central Italy, one in Sardinia, and four in Southern Italy. 549 informants were asked to name and describe food uses of wild botanicals they currently gather and consume. Data showed that gathering, processing and consuming wild food plants are still important activities in all the selected areas. A few botanicals were quoted and cited in multiple areas, demonstrating that there are ethnobotanical contact points among the various Italian regions (Asparagus acutifolius, Reichardia picroides, Cichorium intybus, Foeniculum vulgare, Sambucus nigra, Silene vulgaris, Taraxacum officinale, Urtica dioica, Sonchus and Valerianella spp.). One taxon (Borago officinalis) in particular was found to be among the most quoted taxa in both the Southern and the Northern Italian sites

Prediction of early distant recurrence in upfront resectable pancreatic adenocarcinoma: A multidisciplinary, machine learning-based approach

Despite careful selection, the recurrence rate after upfront surgery for pancreatic adenocarcinoma can be very high. We aimed to construct and validate a model for the prediction of early distant recurrence (<12 months from index surgery) after upfront pancreaticoduodenectomy. After exclusions, 147 patients were retrospectively enrolled. Preoperative clinical and radiological (CT-based) data were systematically evaluated; moreover, 182 radiomics features (RFs) were extracted. Most significant RFs were selected using minimum redundancy, robustness against delineation uncertainty and an original machine learning bootstrap-based method. Patients were split into training (n = 94) and validation cohort (n = 53). Multivariable Cox regression analysis was first applied on the training cohort; the resulting prognostic index was then tested in the validation cohort. Clinical (serum level of CA19.9), radiological (necrosis), and radiomic (SurfAreaToVolumeRatio) features were significantly associated with the early resurge of distant recurrence. The model combining these three variables performed well in the training cohort (p = 0.0015,HR = 3.58,95%CI = 1.98–6.71) and was then confirmed in the validation cohort (p = 0.0178,HR = 5.06,95%CI = 1.75–14.58). The comparison of survival curves between low and high-risk patients showed a p-value <0.0001. Our model may help to better define resectability status, thus providing an actual aid for pancreatic adenocarcinoma patients’ management (upfront surgery vs. neoadjuvant chemotherapy). Independent validations are warranted

The RNA-Binding protein HuR and the members of miR-200 family play an unconventional role in the regulation of c-Jun mRNA stability

MiR-200 family (miR-200a, miR-200b, miR-200c, miR-141, and miR-429) is a cluster of miRNAs highly correlated with epithelial-mesenchymal transition (EMT). A biphasic role of miR-200 family is supported by a lot of studies that show that primary cancer cells downregulate miR-200 expression at the invasive front where they undergo EMT and upregulate miR-200s in the resulting metastasis where mesenchymal to epithelial transition (MET) facilitates colonization of a distant tissue . Therefore, the miR-200 family seems to have a dynamic role in tumor progression, following a still unclear mechanism. In order to clarify this mechanism, in this work we describe the regulation of c-Jun and Dual-specificity phosphatases 1 (DUSP1) mRNA mediated by two members of the miR-200 family: miR-200a and miR-200b. C-Jun is the main component of the AP-1 transcription factor that play an essential role in almost all areas of eukaryotic cellular behavior, DUSP1 is one of many phosphatases coded by the mammalian genome, its role is to dephosphorylate and therefore inactivate the MAP kinases such as ERKs and JNKs. By bioinformatics analysis we identified putative binding sites for both miR-200a and miR-200b in 3’UTR of mRNA of c-Jun and DUSP1 . Surprisingly, our reporter assay revealed an opposite action of the two miRNAs on this 3’UTRs: over expression of miR-200b reduces luciferase activity whereas miR-200a increase it. Interestingly, miR-200a target site is into the well-described ARE for both mRNAs, and this ARE is bounded by the HuR RBP. So we wondered whether this RBP could play a role in this non canonical regulation. After transfection of the siRNA against HuR, we lost the stabilizing effect of miR-200a, suggesting the presence of a potential interaction between the RBP and the miR-200a on the mRNAs 3’-UTR. These results suggest a new regulatory mechanism for microRNA in cooperation with HuR and highlight a new potential role for miR-200a in tumor progression

Gut Microbes and Circulating Cytokines in Preterm Infants with Growth Failure.

BACKGROUND: Growth failure (GF) is a multifactorial problem in preterm infants. The intestinal microbiome and inflammation may contribute to GF. OBJECTIVES: This studys objective was to compare the gut microbiome and plasma cytokines in preterm infants with and without GF. METHODS: This was a prospective cohort study of infants with birth weights of &lt;1750 g. Infants with a weight or length z-score change from birth to discharge or death that was less than or equal to -0.8 (GF group) were compared with infants without GF [control (CON) group]. The primary outcome was the gut microbiome (at weeks 1-4 of age), assessed by 16S rRNA gene sequencing using Deseq2. Secondary outcomes included inferred metagenomic function and plasma cytokines. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States determined metagenomic function, which was compared using ANOVA. Cytokines were measured by 2-multiplexed immunometric assays and compared using Wilcoxon tests and linear mixed models. RESULTS: GF (n = 14) and CON group (n = 13) had similar median (IQR) birth weight (1380 [780-1578] g vs. 1275 [1013-1580] g) and gestational age (29 [25-31] weeks vs. 30 [29-32] weeks). Compared with the CON group, the GF group had a greater abundance of Escherichia/Shigella in weeks 2 and 3, Staphylococcus in week 4, and Veillonella in weeks 3 and 4 (P-adjusted &lt; 0.001 for all). Plasma cytokine concentrations did not differ significantly between the cohorts. When all time points are combined, fewer microbes were involved in TCA cycle activity in the GF group compared with the CON group (P = 0.023). CONCLUSIONS: In this study, when compared with CON infants, GF infants had a distinct microbial signature with increased Escherichia/Shigella and Firmicutes and fewer microbes associated with energy production at later weeks of hospitalization. These findings may suggest a mechanism for aberrant growth

Distinct roles of v-Jun:ATF and v-Jun:Fos dimers in skeletal muscle differentiation

The Jun oncoprotein is the major component of the transcriptional complex AP-1, which is involved in several cell functions. Constitutive activation of AP-1 is required for cell transformation, and also occurs in distinct human tumor cells. Jun is able to dimerize with different partners including Fos family members and ATF proteins providing AP-1 with high flexibility in gene regulation and functions. Particularly, by using mutants selective for Fos proteins or ATF2-like proteins, it has been demonstrated that v-Jun-induced transformation phenotype consists of, at least, two distinct, complementing genetic programs. It has been long known that transformation of myogenic cells by v-Jun, as well as by activated c-Jun, prevents terminal differentiation. In order to better dissect the transformation activity exerted by Jun in myogenic cells, C2C12 cells were infected with retroviral vectors expressing v-Jun mutants selective for Fos proteins or ATF2-like proteins. The analysis of the different cell population revealed opposite phenotypes induced by the different mutants. Data supporting the major role of v-Jun:ATF dimer in the inhibition of terminal differentiation will be presented

Leptin induction following irradiation is a conserved feature in mammalian epithelial cells and tissues

PURPOSE: Leptin (LEP) is a peptide hormone with multiple physiological functions. Besides its systemic actions, it has important peripheral roles such as a mitogen action on keratinocytes following skin lesions. We previously showed that LEP mRNA is significantly induced in response to neutron irradiation in mouse skin and that the protein increases in the irradiated epidermis and in the related subcutaneous adipose tissue. In this work, we investigated the post-transcriptional regulation of LEP by miRNAs and the conservation of LEP's role in radiation response in human cells. METHODS: We used microarray analysis and real-time polymerase chain reaction (RT-PCR) to analyze modulation of miRNAs potentially targeting LEP in mouse skin following irradiation and bioinformatic analysis of transcriptome of irradiated human cell lines and cancer tissues from radiotherapy-treated patients to evaluate LEP expression. RESULTS AND CONCLUSIONS: We show that a network of miRNAs potentially targeting LEP mRNA is modulated in irradiated mouse skin and that LEP itself is significantly modulated by irradiation in human epithelial cell lines and in breast cancer tissues from radiotherapy-treated patients. These results confirm and extend the previous evidence that LEP has a general and important role in the response of mammalian cells to irradiation