HnRNPK maintains single strand RNA through controlling double-strand RNA in mammalian cells

Although antisense transcription is a widespread event in the mammalian genome, double-stranded RNA (dsRNA) formation between sense and antisense transcripts is very rare and mechanisms that control dsRNA remain unknown. By characterizing the FGF-2 regulated transcriptome in normal and cancer cells, we identified sense and antisense transcripts IER3 and IER3-AS1 that play a critical role in FGF-2 controlled oncogenic pathways. We show that IER3 and IER3-AS1 regulate each other's transcription through HnRNPK-mediated post-transcriptional regulation. HnRNPK controls the mRNA stability and colocalization of IER3 and IER3-AS1. HnRNPK interaction with IER3 and IER3-AS1 determines their oncogenic functions by maintaining them in a single-stranded form. hnRNPK depletion neutralizes their oncogenic functions through promoting dsRNA formation and cytoplasmic accumulation. Intriguingly, hnRNPK loss-of-function and gain-of-function experiments reveal its role in maintaining global single- and double-stranded RNA. Thus, our data unveil the critical role of HnRNPK in maintaining single-stranded RNAs and their physiological functions by blocking RNA-RNA interactions.

NBAT1/CASC15-003/USP36 control MYCN expression and its downstream pathway genes in neuroblastoma

Background

MYCN has been an attractive therapeutic target in neuroblastoma considering the widespread amplification of the MYCN locus in neuroblastoma, and its established role in neuroblastoma development and progression. Thus, understanding neuroblastoma-specific control of MYCN expression at the transcriptional and post-transcriptional level would lead to identification of novel MYCN-dependent oncogenic pathways and potential therapeutic strategies.

Methods

By performing loss- and gain-of-function experiments of the neuroblastoma hotspot locus 6p22.3 derived lncRNAs CASC15-003 and NBAT1, together with coimmunoprecipitation and immunoblotting of MYCN, we have shown that both lncRNAs post-translationally control the expression of MYCN through regulating a deubiquitinase enzyme USP36. USP36 oncogenic properties were investigated using cancer cell lines and in vivo models. RNA-seq analysis of loss-of-function experiments of CASC15-003/NBAT1/MYCN/USP36 and JQ1-treated neuroblastoma cells uncovered MYCN-dependent oncogenic pathways.

Results

We show that NBAT1/CASC15-003 control the stability of MYCN protein through their common interacting protein partner USP36. USP36 harbors oncogenic properties and its higher expression in neuroblastoma patients correlates with poor prognosis, and its downregulation significantly reduces tumor growth in neuroblastoma cell lines and xenograft models. Unbiased integration of RNA-seq data from CASC15-003, NBAT1, USP36, and MYCN knockdowns and neuroblastoma cells treated with MYCN inhibitor JQ1, identified genes that are jointly regulated by the NBAT1/CASC15-003/USP36/MYCN pathway. Functional experiments on one of the target genes, COL18A1, revealed its role in the NBAT1/CASC15-003-dependent cell adhesion feature in neuroblastoma cells.

Conclusion

Our data show post-translational regulation of MYCN by NBAT1/CASC15-003/USP36, which represents a new regulatory layer in the complex multilayered gene regulatory network that controls MYCN expression.

LY6K-AS lncRNA is a lung adenocarcinoma prognostic biomarker and regulator of mitotic progression

Recent advances in genomics unraveled several actionable mutational drivers in lung cancer, leading to promising therapies such as tyrosine kinase inhibitors and immune checkpoint inhibitors. However, the tumors' acquired resistance to the newly-developed as well as existing therapies restricts life quality improvements. Therefore, we investigated the noncoding portion of the human transcriptome in search of alternative actionable targets. We identified an antisense transcript, LY6K-AS, with elevated expression in lung adenocarcinoma (LUAD) patients, and its higher expression in LUAD patients predicts poor survival outcomes. LY6K-AS abrogation interfered with the mitotic progression of lung cancer cells resulting in unfaithful chromosomal segregation. LY6K-AS interacts with and stabilizes 14-3-3 proteins to regulate the transcription of kinetochore and mitotic checkpoint proteins. We also show that LY6K-AS regulates the levels of histone H3 lysine 4 trimethylation (H3K4me3) at the promoters of kinetochore members. Cisplatin treatment and LY6K-AS silencing affect many common pathways enriched in cell cycle-related functions. LY6K-AS silencing affects the growth of xenografts derived from wildtype and cisplatin-resistant lung cancer cells. Collectively, these data indicate that LY6K-AS silencing is a promising therapeutic option for LUAD that inhibits oncogenic mitotic progression.

Subcellular Distribution of p53 by the p53-Responsive lncRNA NBAT1 Determines Chemotherapeutic Response in Neuroblastoma

Neuroblastoma has a low mutation rate for the p53 gene. Alternative ways of p53 inactivation have been proposed in neuroblastoma, such as abnormal cytoplasmic accumulation of wild-type p53. However, mechanisms leading to p53 inactivation via cytoplasmic accumulation are not well investigated. Here we show that the neuroblastoma risk-associated locus 6p22.3-derived tumor suppressor NBAT1 is a p53-responsive lncRNA that regulates p53 subcellular levels. Low expression of NBAT1 provided resistance to genotoxic drugs by promoting p53 accumulation in cytoplasm and loss from mitochondrial and nuclear compartments. Depletion of NBAT1 altered CRM1 function and contributed to the loss of p53-dependent nuclear gene expression during genotoxic drug treatment. CRM1 inhibition rescued p53-dependent nuclear functions and sensitized NBAT1-depleted cells to genotoxic drugs. Combined inhibition of CRM1 and MDM2 was even more effective in sensitizing aggressive neuroblastoma cells with p53 cytoplasmic accumulation. Thus, our mechanistic studies uncover an NBAT1-dependent CRM1/MDM2-based potential combination therapy for patients with high-risk neuroblastoma. SIGNIFICANCE: This study shows how a p53-responsive lncRNA mediates chemotherapeutic response by modulating nuclear p53 pathways and identifies a potential treatment strategy for patients with high-risk neuroblastoma.

Short- and long-term beneficial effects of medicinal mineral water administration

Medicinal mineral water, being provided by recognized immunosuppressive properties, results useful for treating many pathological conditions. A well-known source of sulfurous and oligomer medicinal mineral waters is located in Caramanico Terme (Pescara, Italy). Caramanico Terme is a small town in the Majella's National Park, and its precious and peculiar environment offers a medicinal mineral water (also known as cures or crenotherapy), that since 1576 is administrated to a large number of patients (around 15,000 per year). However, no scientific conclusions on the efficacy of Caramanico's Terme medicinal mineral water properties are available. Therefore, we have carried out an epidemiological study, enrolling a population of 370 subjects that have received crenotherapy. Such a population has been also compared to a control group of individuals (untreated, N = 287), never undergone any medicinal mineral water administration. Detailing the geomorphological characteristics of Caramanico Terme environment, we have also analyzed the results of the study that showed that pathology-relapses, as well as related manifestations of symptoms and drug employments, were largely reduced after one or more cycles of crenotherapy. On the other hand, a sub-group of subjects receiving crenotherapy for more than 5 years (N = 166) presented a highly reduced prevalence of a large spectrum of pathologies (cardiovascular, inflammatory, neurological and cancer diseases), with respect to an overlapping population (in terms of age and genders) of untreated subjects. We have also clarified the role of aging and long-term effects of medicinal mineral-water administration. Altogether, these data indicated that the clinical employment of Caramanico's Terme medicinal mineral water produces short- as well as long-term beneficial effects, both with respect to the amelioration of life quality of patients and in reducing the probability to develop major disabling pathologies (i.e., cardiovascular, cancer and neurological diseases). Therefore, these data will open novel strategies for a larger application of crenotherapy.

DNA methylation of shelf, shore and open sea CpG positions distinguish high microsatellite instability from low or stable microsatellite status colon cancer stem cells

Aim: To investigate the genome-wide methylation of genetically characterized colorectal cancer stem cell (CR-CSC) lines. Materials & methods: Eight CR-CSC lines were isolated from primary colorectal cancer (CRC) tissues, cultured and characterized for aneuploidy, mutational status of CRC-related genes and microsatellite instability (MSI). Genome-wide DNA methylation was assessed by MethylationEPIC microarray. Results: We describe a distinctive methylation pattern that is maintained following in vivo passages in immune-compromised mice. We identified an epigenetic CR-CSC signature associated with MSI. We noticed that the preponderance of the differentially methylated positions do not reside at CpG islands, but spread to shelf and open sea regions. Conclusion: Given that CRCs with MSI-high status have a lower metastatic potential, the identification of a MSI-related methylation signature could provide new insights and possible targets into metastatic CRC.

MicroRNAs in Autoimmunity and Hematological Malignancies

Autoimmunity and hematological malignancies are often concomitant in patients. A causal bidirectional relationship exists between them. Loss of immunological tolerance with inappropriate activation of the immune system, likely due to environmental and genetic factors, can represent a breeding ground for the appearance of cancer cells and, on the other hand, blood cancers are characterized by imbalanced immune cell subsets that could support the development of the autoimmune clone. Considerable effort has been made for understanding the proteins that have a relevant role in both processes; however, literature advances demonstrate that microRNAs (miRNAs) surface as the epigenetic regulators of those proteins and control networks linked to both autoimmunity and hematological malignancies. Here we review the most up-to-date findings regarding the miRNA-based molecular mechanisms that underpin autoimmunity and hematological malignancies.

Hsa-miR-155-5p drives aneuploidy at early stages of cellular transformation

Hsa-miR-155-5p (miR-155) is overexpressed in most solid and hematological malignancies. It promotes loss of genomic integrity in cancer cells by targeting genes involved in microsatellite instability and DNA repair; however, the link between miR-155 and aneuploidy has been scarcely investigated. Here we describe a novel mechanism by which miR-155 causes chromosomal instability. Using osteosarcoma cells (U2OS) and normal human dermal fibroblast (HDF), two well-established models for the study of chromosome congression, we demonstrate that miR-155 targets the spindle checkpoint proteins BUB1, CENP-F, and ZW10, thus compromising chromosome alignment at the metaphase plate. In U2OS cells, exogenous miR-155 expression reduced the recruitment of BUB1, CENP-F, and ZW10 to the kinetochores which resulted in defective chromosome congression. In contrast, during in vitro transformation of HDF by enforced expression of SV40 Large T antigen and human telomerase (HDF_LT/hTERT), inhibition of miR-155 reduced chromosome congression errors and aneuploidy at early passages. Using live-cell imaging we observed that miR-155 delays progression through mitosis, indicating an activated mitotic spindle checkpoint, which likely fails to reduce aneuploidy. Overall, this study provides insight into a mechanism that generates aneuploidy at early stages of cellular transformation, pointing to a role for miR-155 in chromosomal instability at tumor onset.

[An evaluation study of a scale of diabetological education in primary care]

OBJECTIVE

To devise and evaluate a scale of measurement which would permit evaluation at primary care level, of the knowledge that diabetic patients have of diabetes. Secondly, to ascertain the level of knowledge of the sample of diabetic patients attending the Xixona Health Centre.

DESIGN

Non-longitudinal, observational, descriptive study.

SETTING

Primary health care (health centre).

MEASUREMENTS AND MAIN RESULTS

The degree of internal consistency of the diabetes scale of knowledge (DISK) attained a Cronbach Alpha value of 0.87. The coefficients of correlation of each of the factors--defined a priori (general knowledge, diet, exercise, hygiene and self-regulation)--oscillated between 0.77 and 0.83. The Garret index of corrected difficulty was at 0.64. The homogeneity of each item with the questionnaire showed values above 0.31. The reliability measured by means of the KR20 index was 0.86. The odd-even coefficient of reliability was at 0.89. The mean level of correct answers was 70%. A relation was found between the level of knowledge and the variables age and years the patient had been subject to the condition. No relation was found with the treatment, sex, glycaemia or HbA1C level, nor educational level.

CONCLUSIONS

The indices obtained by the scale can be considered to be judiciously acceptable, both in terms of their internal consistency and their ability to characterise. The DISK (ECODI) is, then, a valuable tool in the field of primary health care.