RRP8, associated with immune infiltration, is a prospective therapeutic target in hepatocellular carcinoma.

BACKGROUND: Ribosomal RNA Processing 8 (RRP8) is a nucleolar Rossman fold-like methyltransferase that exhibits increased expression in many malignant tumours. However, the role of RRP8 in hepatocellular carcinoma (HCC) is still uncertain. We explored the relationships between RRP8 and prognosis and immune infiltration, as well as the putative pathological function and mechanism of RRP8 in HCC. METHODS: Analysis of RRP8 expression across cancers was performed by using multiple databases. Associations between RRP8 expression and clinicopathological factors were further examined. Gene enrichment analysis was used to identify various putative biological activities and regulatory networks of RRP8 in HCC. The relationship between RRP8 expression and immune infiltration was confirmed by single-sample gene set enrichment analysis (ssGSEA). Univariate and multivariate Cox regression analyses were conducted to assess the impact of clinical variables on patient outcomes. Furthermore, a nomogram was constructed to estimate survival probability based on multivariate Cox regression analysis. Functional validation of RRP8 in HCC was performed with two different systems: doxycycline-inducible shRNA knockdown and CRISPR-Cas9 knockout. RESULTS: RRP8 was markedly overexpressed in HCC clinical specimens compared to adjacent normal tissues. Further analysis demonstrated that RRP8 was directly connected to multiple clinical characteristics and strongly associated with various immune markers in HCC. Moreover, elevated RRP8 expression indicated an unfavourable prognosis. Our functional studies revealed that both knockdown and knockout of RRP8 dramatically attenuated liver cancer cells to proliferate and migrate. Knockout of RRP8 decreased the phosphorylation of MEK1/2 and ß-catenin-(Y654) signalling pathway components; downregulated downstream signalling effectors, including Cyclin D1 and N-cadherin; and upregulated E-cadherin. CONCLUSIONS: RRP8 is strongly implicated in immune infiltration and could be a potential therapeutic target in HCC.

Feeding Spodoptera exigua larvae with gut-derived Escherichia sp. increases larval juvenile hormone levels inhibiting cannibalism.

Feed quality influences insect cannibalistic behavior and gut microbial communities. In the present study, Spodoptera exigua larvae were fed six different artificial diets, and one of these diets (Diet 3) delayed larval cannibalistic behavior and reduced the cannibalism ratio after ingestion. Diet 3-fed larvae had the highest gut bacterial load (1.396 ± 0.556 × 1014 bacteria/mg gut), whereas Diet 2-fed larvae had the lowest gut bacterial load (3.076 ± 1.368 × 1012 bacteria/mg gut). The gut bacterial composition and diversity of different diet-fed S. exigua larvae varied according to the 16S rRNA gene sequence analysis. Enterobacteriaceae was specific to the Diet 3-fed larval gut. Fifteen culturable bacterial isolates were obtained from the midgut of Diet 3-fed larvae. Of these, ten belonged to Escherichia sp. After administration with Diet 1- or 2-fed S. exigua larvae, two bacterial isolates (SePC-12 and -37) delayed cannibalistic behavior in both tested larval groups. Diet 2-fed larvae had the lowest Juvenile hormone (JH) concentration and were more aggressive against intraspecific predation. However, SePC-12 loading increased the JH hormone levels in Diet 2-fed larvae and inhibited their cannibalism. Bacteria in the larval midgut are involved in the stabilization of JH levels, thereby regulating host larval cannibalistic behavior.

PECAM-1 drives ß-catenin-mediated EndMT via internalization in colon cancer with diabetes mellitus.

BACKGROUND: Diabetes mellitus (DM) is considered to be a risk factor in carcinogenesis and progression, although the biological mechanisms are not well understood. Here we demonstrate that platelet-endothelial cell adhesion molecule 1 (PECAM-1) internalization drives ß-catenin-mediated endothelial-mesenchymal transition (EndMT) to link DM to cancer. METHODS: The tumor microenvironment (TME) was investigated for differences between colon cancer with and without DM by mRNA-microarray analysis. The effect of DM on colon cancer was determined in clinical patients and animal models. Furthermore, EndMT, PECAM-1 and Akt/GSK-3ß/ß-catenin signaling were analyzed under high glucose (HG) and human colon cancer cell (HCCC) supernatant (SN) or coculture conditions by western and immunofluorescence tests. RESULTS: DM promoted the progression and EndMT occurrence of colon cancer (CC). Regarding the mechanism, DM induced PECAM-1 defection from the cytomembrane, internalization and subsequent accumulation around the cell nucleus in endothelial cells, which promoted ß-catenin entry into the nucleus, leading to EndMT occurrence in CC with DM. Additionally, Akt/GSK-3ß signaling was enhanced to inhibit the degradation of ß-catenin, which regulates the process of EndMT. CONCLUSIONS: PECAM-1 defects and/or internalization are key events for ß-catenin-mediated EndMT, which is significantly boosted by enhanced Akt/GSK-3ß signaling in the DM-associated TME. This contributes to the mechanism by which DM promotes the carcinogenesis and progression of CC. Video Abstract.

Relative activity of 15 bacterial strains against the larvae of Helicoverpa armigera, Spodoptera exigua, and Spodoptera litura (Lepidoptera: Noctuidae).

Crystal toxins produced by different strains of entomopathogenic Bacillus thuringiensis (Bt) have been characterized and widely applied as commercial biological pesticides owing to their excellent insecticidal properties. This study aimed to identify novel bacterial strains effective in controlling Spodoptera exigua Hübner, Helicoverpa armigera Hübner, and Spodoptera litura Fabricius. Fifteen culturable bacterial strains were isolated from 60 dead larvae (H. armigera and S. exigua) collected in the field. The biochemical characteristics and 16S rRNA sequences of these strains indicated that one strain (B7) was Lysinibacillus sp., 12 strains (B1, B3, B4, B5, B6, B8, P2, P3, P4, P5, P6, and DW) were Bt kurstaki, and P2-2 and B2 were Bacillus velezensis subsp. Laboratory bioassays indicated that strains B3, P6, B6, and P4 showed high toxicity to second-instar larvae of S. exigua, with LC50 values of 5.11, 6.74, 205.82, and 595.93 µg/ml, respectively; while the strains P5, B5, B6, and P6, were the most efficient against second-instar larvae of H. armigera with LC50 values of 725.82, 11,022.72, 1,282.90, 2,005.28, respectively, and strains DW, P3, P2, and B4 had high insecticidal activity against second-instar larvae of S. litura with LC50 values of 576.69, 1,660.96, 6,309.42, and 5,486.10 µg/ml, respectively. In conclusion, several Bt kurstaki strains with good toxicity potential were isolated and identified in this study. These strains are expected to be useful for biointensive integrated pest management programs to reduce the use of synthetic insecticides.

Comparisons of pathogenic course of two Heliothis virescens ascovirus isolates (HvAV-3i and HvAV-3j) in four noctuid (Lepidoptera) pest species.

Ascoviruses are fatal double-stranded DNA viruses with a special pathogenesis in which cells are converted into vesicles with virions. Several closely related ascovirus isolates that shared more than 90% genomic DNA identity showed different pathogenic courses in previous studies. To investigate the pathogenic differences between the related ascovirus isolates, Heliothis virescens ascovirus 3i (HvAV-3i) and Heliothis virescens ascovirus 3j (HvAV-3j) were used to inoculate four noctuid pest species (Helicoverpa armigera, Mythimna separata, Spodoptera frugiperda, and Spodoptera litura), and the pathogenic indexes were recorded. The mortality of HvAV-3i infected H. armigera and S. frugiperda was approximately 60%, while the other HvAV-infected larvae had mortality rates above 90%. The maximum lethal dilution ratios of HvAV-3i in H. armigera, M. separata, S. frugiperda, and S. litura were 1.90 × 107, 1.90 × 103, 1.90 × 108, and 1.90 × 104 viral genome DNA copies/mL, respectively, while the ratios of HvAV-3j were 8.22 × 106, 8.22 × 102, 8.22 × 105, and 8.22 × 103 viral genome DNA copies/mL, respectively. Extended larval survival time was found in the HvAV-infected larvae; median survival time of the HvAV-infected larvae ranged from 13 to 19 days. An additional larval instar was found in HvAV-infected M. separata, S. frugiperda, and S. litura. Larval growth and food intake were significantly inhibited from 2 days post-infection (dpi) in the tested H. armigera, S. frugiperda, and S. litura after infection with HvAV-3i or HvAV-3j. The detoxification enzyme activity of host larvae was influenced after infection with HvAVs, and two different regulation patterns were detected, one in infected H. armigera and M. separata and the other in S. frugiperda and S. litura. The results obtained in this study provide insights into the pathogenic characteristics of ascoviruses.

Parental Influence in Forming Preschool Children's Eating Behaviors-A Cross-Sectional Survey in Chongqing, China.

Children's eating habits are closely related to their health problems and the outlook for children's nutritional statuses appears poor. A cross-sectional survey was conducted among parents of preschool children from December 2018 to January 2019. Sixteen representative kindergartens in 6 districts of Chongqing, China, were included in the study. We took 2200 samples and collected information by questionnaire and after screening, 1781 questionnaires were valid and finally included in the data analysis (n = 1781). Ordinal logistic regression analysis found that age, fathers' education level, forced diet and perception of children's body shape were factors associated with children's eating behaviors (ordered logistic regression/three-level eating behavior; odds ratios p < 0.05). 80.24% of preschool children may have unhealthy eating behavior in this survey and 80.35% of parents had forced their children to eat. Eating behaviors of preschool children in Chongqing are closely related to family factors. This study provides important insight for parents and health care workers in China to improve preschool-aged children's nutritional behaviors. Intervention programs should focus on parents with low income, low education levels, coercive dietary behaviors and deviated body shape perceptions to reduce children's eating behavioral problems.

Lactobacilli inhibit cervical cancer cell migration in vitro and reduce tumor burden in vivo through upregulation of E-cadherin.

The present study was designed to investigate the antitumor effects of Lactobacillus and the potential mechanisms. Cell Counting Kit-8 (CCK-8) assays were carried out to determine suitable doses for investigating the inhibitory effect of lactobacilli on cell migration ability of HeLa and U14 cells in vitro. In addition, western blot assays were performed to investigate the possible mechanisms corresponding to its antitumor effects. Furthermore, a xenograft mouse model was established for investigating the E-cadherin expression in tumor tissues after treatment with lactobacilli. Our results showed that live lactobacilli [multiplicity of infection (MOI) of 1,000:1] significantly possessed inhibitory effects on cell migration ability of cervical cancer cells. Lactobacilli (MOI: 1,000:1) significantly upregulated E-cadherin expressions in HeLa and U14 cells (p<0.05). On the contrary, our results showed that inactivated lactobacilli could not affect the E-cadherin expression levels in HeLa and U14 cells. Similar to the western blot assay, immunohistochemistry results also indicated that lactobacilli treatment significantly upregulated E-cadherin in tumor tissues (p<0.05). In conclusion, our results above suggest that lactobacilli have the potential for inhibiting the migratory ability of cervical cancer cell lines, and the possible pharmacological mechanism may be closely related to the upregulation of E-cadherin.

budC knockout in Klebsiella pneumoniae for bioconversion from glycerol to 1,3-propanediol.

2,3-Butanediol (2,3-BD) is a major by-product of 1,3-propanediol (1,3-PDO) fermentation by Klebsiella pneumoniae ZG25. It not only consumes large amounts of its carbon source and nicotinamide adenine dinucleotide to diminish synthesis of 1,3-PDO, but also serves as an obstacle to high-purity 1,3-PDO in downstream processes. To decrease the formation of 2,3-BD and make an intrinsic improvement in 1,3-PDO production, the budC gene in K. pneumoniae, coding 2,3-BD dehydrogenase, which is a key gene of the 2,3-BD pathway, was successfully knocked out using the Red recombination system described in this paper. The results of the mutant fed-batch fermentation showed that the 1,3-PDO concentration, productivity per cell dry weight, and conversion rate increased to 880 mmol L(-1) , 22.0 mmol L(-1) h(-1) , and 0.700 mol mol(-1) , respectively, increasing by 10%, 15%, and 11% compared with the parent strain. Meanwhile, 2,3-BD was still found in fermentation broth with the 2,3-BD metabolic pathway blocked, which implies that K. pneumoniae possesses a pathway of the 2,3-BD cycle as a replenishment pathway.