LINC01342 promotes the progression of ovarian cancer by absorbing microRNA-30c-2-3p to upregulate HIF3A

Ovarian cancer (OC) is a highly prevalent gynecologic malignancy and its mortality is extremely high. Therefore, the development of novel therapeutic approaches for OC is of great significance. In this study, LINC01342 was upregulated in OC tissue in the GSE38666 microarray and in tumor tissue samples collected in our center. The silencing of LINC01342 suppressed the proliferative and metastatic capacities of A2780 and HO8910 cells. Subcellular distribution assays showed that LINC01342 was mainly enriched in the cytoplasm. Subsequently, the downregulation of microRNA-30c-2-3p was proven to be the target of LINC01342. The silencing of microRNA-30c-2-3p enhanced the clonality and migratory capacity of OC cells. Moreover, the silencing of microRNA-30c-2-3p could reverse the inhibited migration and clonality in OC cells caused by LINC01342 knockdown. In addition, hypoxia-inducible factor 3 subunit α (HIF3A) was proven to be the target gene of microRNA-30c-2-3p, which was upregulated. HIF3A was negatively regulated by microRNA-30c-2-3p but positively regulated by LINC01342 in OC cells. An RNA binding protein immunoprecipitation assay showed that microRNA-30c-2-3p, LINC01342, and HIF3A could bind to argonaute RISC catalytic component 2. The overexpression of HIF3A reversed the inhibited migration and clonality in OC cells with LINC01342 knockdown. By analyzing the follow-up data from the enrolled OC patients, the LINC01342 and HIF3A levels were negatively correlated with prognosis, while the microRNA-30c-2-3p level was positively correlated with the same. In short, the upregulated LINC01342 in OC absorbs microRNA-30c-2-3p to release HIF3A. Thus, upregulated HIF3A expression accelerates the progression of OC.     

Quantification de l’activité dopaminergique striatale en TEP à la 18F-DOPA : quels paramètres choisir en routine ?

Aim of the studyFunctional assessment of the nigrostriatal dopaminergic pathway (NSDP) is still largely dominated by SPECT imaging of presynaptic dopamine transporters. Because of greater performance characteristics and a potential medico-economic added value, 18F-DOPA PET may advantageously replace SPECT procedures. Clinical analysis of 18F-DOPA PET images is mainly based on visual assessment, a parameter which may be empirically affected by a low reproducibility. We assessed several reproducible semi-quantitative parameters applicable in clinical routine.Material and methodsSeventy-two patients (18 control subjects, 55.2 ± 13.4 years; 54 patients without confirmed Parkinson's disease (no-PD patients): 74.0 ± 9.9 years) were prospectively referred for a 18F-DOPA PET brain study. 18F-DOPA striatal uptake, which reflects the activity level of L-DOPA decarboxylase (DDC), was quantified using calculation methods of SUV in several striatal VOI. Background activity in occipital VOI (non specific uptake) was taken into consideration to assess specific uptake.ResultsDespite the absence of standard of truth regarding the medical status of no-PD patients, the most effective quantitative parameter to assess specific striatal dopaminergic activity was the putamen-to-occipital ratio. According to our data, activity level of DCC might decrease with age.ConclusionAn accurate and early in-vivo detection of NSDP alteration is a critical issue at the earliest stages of PD. Despite limits of this preliminary study, simple semi-quantitative parameters appear to be valuable tools to address problems of classification reproducibility in clinical practice.     

5.3 S RNA is a discrete cleavage product from the 5′-terminus of 18 S RNA of rat liver ribosomes

A 5.3 S RNA species observed in urea-gel electrophoretic analysis of the RNA of the small ribosomal subunit of rat liver has been identified from its sequence as the 5′-terminal 133–134 base fragment of 18 S RNA. Presumably it is cleaved by an endogenous endonuclease when the ribosomal subunits are dissociated, because it usually is not observed in 18 S RNA obtained by direct extraction of cells or tissues.     

Microbial Metabolite Signaling Is Required for Systemic Iron Homeostasis

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Mutagenesis and mutation transfer induced by ultraviolet light in plasmid-cloned DNA

We describe here simple techniques for increasing the frequency of UV-induced mutations in a DNA fragment cloned in plasmid pBR322. Irradiation of both the host and the plasmid DNA before transformation is necessary to produce new mutations in the plasmid DNA, presumably because the UV-damaged pBR322 replicon cannot efficiently induce the error-prone repair pathway of Escherichia coli. In contrast, U V irradiation of the plasmid DNA alone before transformation primarily causes the transfer of preexisting mutations from the host chromosome to homologous DNA present in the plasmid. The only other kind of mutants obtained were large deletions of the plasmid DNA. Two chromosomal mutations from the host galK gene and one from the lacZ gene have been transferred to the plasmid by UV irradiation of the plasmid DNA alone. The technique can thus be of general use.     

Characterization and preliminary crystallographic data on the VL-related fragment of the human kI Bence Jones protein Wat

A “naturally occurring” human κI V_L dimer, designated Wat, has been isolated and crystallized. Protein Wat consists of two non-covalently bound monomers, each having a molecular weight of ~ 11,500. The monomer subunit is composed of an entire variable region light chain (V_L) domain closely homologous to that of the κI Bence Jones protein Roy (Hilschmann &; Craig, 1965) as evidenced from amino acid composition, tryptic peptide map, and sequence analysis. Immunochemical studies substantiated that protein Wat is of the κ chain subgroup κI and lacks the isotypic and allotypic antigenic determinants associated with the κ constant region light chain domain. Two types of crystals of V_L dimer Wat were obtained from ammonium sulfate or polyethylene glycol solutions. The type I crystals have unit cell dimensions of $\text{a = b = 82.6}\text{A}\text{?}\text{, c = 60.3}\text{A}\text{?}$, and the space group is hexagonal P6₂ or P6₄. The asymmetric unit consists of one V_L dimer; the fractional volume of unit cell occupied by solvent is 0.51. The unit cell dimensions of the type II crystals are $\text{a = b = 1,08.3}\text{A}\text{?}\text{, c = 108.8}\text{A}\text{?}$; the space group is hexagonal P6₁22 or P6₅22. Three variable domains constitute the asymmetric unit of the type II crystals; the fractional value of the solvent (0.52) is compatible with the value obtained for the type I crystals.     

MicroRNA-155 Regulates Cell Survival,Growth, and Chemosensitivity by Targeting FOXO3a in Breast Cancer

Breast cancer is the second leading cause of cancer death in women. Despite improvement in treatment over the past few decades, there is an urgent need for development of targeted therapies. miR-155 (microRNA-155) is frequently up-regulated in breast cancer. In this study, we demonstrate the critical role of miR-155 in regulation of cell survival and chemosensitivity through down-regulation of FOXO3a in breast cancer. Ectopic expression of miR-155 induces cell survival and chemoresistance to multiple agents, whereas knockdown of miR-155 renders cells to apoptosis and enhances chemosensitivity. Further, we identified FOXO3a as a direct target of miR-155. Sustained overexpression of miR-155 resulted in repression of FOXO3a protein without changing mRNA levels, and knockdown of miR-155 increases FOXO3a. Introduction of FOXO3a cDNA lacking the 3′-untranslated region abrogates miR-155-induced cell survival and chemoresistance. Finally, inverse correlation between miR-155 and FOXO3a levels were observed in a panel of breast cancer cell lines and tumors. In conclusion, our study reveals a molecular link between miR-155 and FOXO3a and presents evidence that miR-155 is a critical therapeutic target in breast cancer.     

DYRK1A inhibition suppresses STAT3/EGFR/Met signalling and sensitizes EGFR wild‐type NSCLC cells to AZD9291

DYRK1A is considered a potential cancer therapeutic target, but the role of DYRK1A in NSCLC oncogenesis and treatment requires further investigation. In our study, high DYRK1A expression was observed in tumour samples from patients with lung cancer compared with normal lung tissues, and the high levels of DYRK1A were related to a reduced survival time in patients with lung cancer. Meanwhile, the DYRK1A inhibitor harmine could suppress the proliferation of NSCLC cells compared to that of the control. As DYRK1A suppression might be effective in treating NSCLC, we next explored the possible specific molecular mechanisms that were involved. We showed that DYRK1A suppression by siRNA could suppress the levels of EGFR and Met in NSCLC cells. Furthermore, DYRK1A siRNA could inhibit the expression and nuclear translocation of STAT3. Meanwhile, harmine could also regulate the STAT3/EGFR/Met signalling pathway in human NSCLC cells. AZD9291 is effective to treat NSCLC patients with EGFR‐sensitivity mutation and T790 M resistance mutation, but the clinical efficacy in patients with wild‐type EGFR remains modest. We showed that DYRK1A repression could enhance the anti‐cancer effect of AZD9291 by inducing apoptosis and suppressing cell proliferation in EGFR wild‐type NSCLC cells. In addition, harmine could enhance the anti‐NSCLC activity of AZD9291 by modulating STAT3 pathway. Finally, harmine could enhance the anti‐cancer activity of AZD9291 in primary NSCLC cells. Collectively, targeting DYRK1A might be an attractive target for AZD9291 sensitization in EGFR wild‐type NSCLC patients.