Prostate-specific PTen deletion in mice activates inflammatory microRNA expression pathways in the epithelium early in hyperplasia development

PTen loss is one of the most frequent events in prostate cancer both at the initiation stage and during late stage metastatic development. The mouse model of prostate-specific probasin-mediated Pten deletion leads to prostate intraepithelial neoplasia (PIN) leading to adenocarcinoma. Using this model, we analysed the miR and mRNA transcriptome profile of Pten−/− PIN versus wild type age-matched prostate tissues and analysed the effects of Pten loss on miR expression in the early neoplastic process. At the PIN stage, Pten loss significantly changed the expression of over 20 miRNAs and over 4000 genes. The observed miR expression indicated a strong immunological cohort, which is seen in many human and mouse cancers and is thought to derive from infiltrating B and T immune cells. However, upon in situ hybridisation, these immunologically related miRs did not correlate with immune cell location, and emanated from the prostate epithelium itself and not from the associated immune cells present. Growing Pten−/− prostate cells in culture showed that the overexpressed miRNAs seen in Pten−/− were directly in response to the overactive PI3 kinase pathway and were in part responsible in reducing target gene expression levels. Inhibition of PI3 kinase downstream regulators, or re-introducing wild type PtencDNA reduced miR overexpression resulting in increased miR target gene expression. MiR inhibitors also showed this pattern, and synergised with an mTORC1 inhibitor. Overall, Pten deletion in the prostate epithelium activated a cohort of inflammation-related miRs usually associated with immune responses from B and T cells. These oncomiRs may then accelerate carcinogenesis

Prohibitin Links Cell Cycle, Motility and Invasion in Prostate Cancer Cells

Prohibitin (PHB) is a tumour suppressor gene with several different molecular activities. PHB overexpression leads to G1/S-phase cell cycle arrest, and PHB represses the androgen receptor (AR) in prostate cancer cells. PHB interacts with and represses members of the E2F family in a manner that may also be AR-linked, therefore making the AR:PHB:E2F interaction axis highly complex. PHB siRNA increased the growth and metastatic potential of LNCaP mouse xenografts in vivo. Conversely, PHB ectopic cDNA overexpression affected several hundred genes in LNCaP cells. Furthermore, gene ontology analysis showed that in addition to cell cycle regulation, several members of the WNT family were significantly downregulated (WNT7B, WNT9A and WNT10B), as well as pathways for cell adhesion. Online GEO data studies showed PHB expression to be decreased in clinical cases of metastatic prostate cancer, and to be correlated with higher WNT expression in metastasis. PHB overexpression reduced prostate cancer cell migration and motility in wound-healing assays, reduced cell invasion through a Matrigel layer and reduced cellular attachment. In LNCaP cells, WNT7B, WNT9A and WNT10B expression were also upregulated by androgen treatment and downregulated by androgen antagonism, indicating a role for AR in the control of these WNT genes. However, these WNTs were strongly cell cycle regulated. E2F1 cDNA ectopic expression and PHB siRNA (both cell cycle promoting effects) increased WNT7B, WNT9A and WNT10B expression, and these genes were also upregulated as cells were released from G1 to S phase synchronisation, indicating further cell cycle regulation. Therefore, the repressive effects of PHB may inhibit AR, E2F and WNT expression and its loss may increase metastatic potential in human prostate cancer

Outlines of Microbiology Programme at International Crops Research Institute for the Semi-Arid Tropics

Our emphasis will be on, biological nitrogen fixation by pulse and forage legumes, and by bacteria closely associated with the roots of the cereals, sorghum and mlllet. We will examine the numbers of rhizobia in the soils of Semi-arid tropics capable of nodulating the legumes in the ICRISAT crop improvement programme, namely pigeon pea, groundnut and chickpea, and will look at the effect of season and cropping sequence on these numbers..

Scanning electron microscopy of plant roots

RSEP-635

Wnt-11 expression promotes invasiveness and correlates with survival in human pancreatic ductal adeno carcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest forms of cancer, proving difficult to manage clinically. Wnt-11, a developmentally regulated gene producing a secreted protein, has been associated with various carcinomas but has not previously been studied in PDAC. The present study aimed to elucidate these aspects first in vitro and then in a clinical setting in vivo. Molecular analyses of Wnt-11 expression as well as other biomarkers involved qRT-PCR, RNA-seq and siRNA. Proliferation was measured by MTT; invasiveness was quantified by Boyden chamber (Matrigel) assay. Wnt-11 mRNA was present in three different human PDAC cell lines. Wnt-11 loss affected epithelial-mesenchymal transition and expression of neuronal and stemness biomarkers associated with metastasis. Indeed, silencing Wnt-11 in Panc-1 cells significantly inhibited their Matrigel invasiveness without affecting their proliferative activity. Consistently with the in vitro data, human biopsies of PDAC showed significantly higher Wnt-11 mRNA levels compared with matched adjacent tissues. Expression was significantly upregulated during PDAC progression (TNM stage I to II) and maintained (TNM stages III and IV). Wnt-11 is expressed in PDAC in vitro and in vivo and plays a significant role in the pathophysiology of the disease; this evidence leads to the conclusion that Wnt-11 could serve as a novel, functional biomarker PDA

Non-symbiotic Nitrogen Fixation and Soil Fertility

Soils in the semi-arid tropics (SAn are low in nitrogen and yet they continue to support most of the world's.milletsand sorghum production with virtually no addition df fertiliser. Legumes seem to play only a small role in the maintenance of soil fertility under the present management and cropping patterns. High levels of N can accumulate in soil under certain fallows planted to grasses such as Andropogon goyonus. Mineralisation mtes of 4 to 5% per,annum provide up to 70 kg N I ha per annum as nitrate, some of which may leach to soil depths of I to 2 m. Nitrogen removal in pearl millet or sorghum crops in such soils can beas much as 150 kg N/ha, depending on the cultivar and the season. Since inputs from other sources such as rainfall are small, the maintenance of equilibrium levels of soil N depends on biological N2 fixation. Bacteria associated with the root systems of sorghum, millets and some tropical grasses are involved, as well as blue-green algal crusts

The Prediction of miRNAs in SARS-CoV-2 Genomes: hsa-miR Databases Identify 7 Key miRs Linked to Host Responses and Virus Pathogenicity-Related KEGG Pathways Significant for Comorbidities.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a member of the betacoronavirus family, which causes COVID-19 disease. SARS-CoV-2 pathogenicity in humans leads to increased mortality rates due to alterations of significant pathways, including some resulting in exacerbated inflammatory responses linked to the "cytokine storm" and extensive lung pathology, as well as being linked to a number of comorbidities. Our current study compared five SARS-CoV-2 sequences from different geographical regions to those from SARS, MERS and two cold viruses, OC43 and 229E, to identify the presence of miR-like sequences. We identified seven key miRs, which highlight considerable differences between the SARS-CoV-2 sequences, compared with the other viruses. The level of conservation between the five SARS-CoV-2 sequences was identical but poor compared with the other sequences, with SARS showing the highest degree of conservation. This decrease in similarity could result in reduced levels of transcriptional control, as well as a change in the physiological effect of the virus and associated host-pathogen responses. MERS and the milder symptom viruses showed greater differences and even significant sequence gaps. This divergence away from the SARS-CoV-2 sequences broadly mirrors the phylogenetic relationships obtained from the whole-genome alignments. Therefore, patterns of mutation, occurring during sequence divergence from the longer established human viruses to the more recent ones, may have led to the emergence of sequence motifs that can be related directly to the pathogenicity of SARS-CoV-2. Importantly, we identified 7 key-microRNAs (miRs 8066, 5197, 3611, 3934-3p, 1307-3p, 3691-3p, 1468-5p) with significant links to KEGG pathways linked to viral pathogenicity and host responses. According to Bioproject data (PRJNA615032), SARS-CoV-2 mediated transcriptomic alterations were similar to the target pathways of the selected 7 miRs identified in our study. This mechanism could have considerable significance in determining the symptom spectrum of future potential pandemics. KEGG pathway analysis revealed a number of critical pathways linked to the seven identified miRs that may provide insight into the interplay between the virus and comorbidities. Based on our reported findings, miRNAs may constitute potential and effective therapeutic approaches in COVID-19 and its pathological consequences

Implementing Groundness Analysis with Definite Boolean Functions

The domain of definite Boolean functions, Def, can be used to express the groundness of, and trace grounding dependencies between, program variables in (constraint) logic programs. In this paper, previously unexploited computational properties of Def are utilised to develop an efficient and succinct groundness analyser that can be coded in Prolog. In particular, entailment checking is used to prevent unnecessary least upper bound calculations. It is also demonstrated that join can be defined in terms of other operations, thereby eliminating code and removing the need for preprocessing formulae to a normal form. This saves space and time. Furthermore, the join can be adapted to straightforwardly implement the downward closure operator that arises in set sharing analyses. Experimental results indicate that the new Def implementation gives favourable results in comparison with BDD-based groundness analyses