The Long Noncoding RNA CCAT2 Induces Chromosomal Instability Through BOP1-AURKB Signaling

BACKGROUND & AIMS: Chromosomal instability (CIN) is a carcinogenesis event that promotes metastasis and resistance to therapy by unclear mechanisms. Expression of the colon cancer-associated transcript 2 gene (CCAT2), which encodes a long noncoding RNA (lncRNA), associates with CIN, but little is known about how CCAT2 lncRNA regulates this cancer enabling characteristic.METHODS: We performed cytogenetic analysis of colorectal cancer (CRC) cell lines (HCT116, KM12C/SM, and HT29) overexpressing CCAT2 and colon organoids from C57BL/6N mice with the CCAT2 transgene and without (controls). CRC cells were also analyzed by immunofluorescence microscopy, gamma-H2AX, and senescence assays. CCAT2 transgene and control mice were given azoxymethane and dextran sulfate sodium to induce colon tumors. We performed gene expression array and mass spectrometry to detect downstream targets of CCAT2 lncRNA. We characterized interactions between CCAT2 with downstream proteins using MS2 pull-down, RNA immunoprecipitation, and selective 2'-hydroxyl acylation analyzed by primer extension analyses. Downstream proteins were overexpressed in CRC cells and analyzed for CIN. Gene expression levels were measured in CRC and non-tumor tissues from 5 cohorts, comprising more than 900 patients.RESULTS: High expression of CCAT2 induced CIN in CRC cell lines and increased resistance to 5-fluorouracil and oxaliplatin. Mice that expressed the CCAT2 transgene developed chromosome abnormalities, and colon organoids derived from crypt cells of these mice had a higher percentage of chromosome abnormalities compared with organoids from control mice. The transgenic mice given azoxymethane and dextran sulfate sodium developed more and larger colon polyps than control mice given these agents. Microarray analysis and mass spectrometry indicated that expression of CCAT2 increased expression of genes involved in ribosome biogenesis and protein synthesis. CCAT2 lncRNA interacted directly with and stabilized BOP1 ribosomal biogenesis factor (BOP1). CCAT2 also increased expression of MYC, which activated expression of BOP1. Overexpression of BOP1 in CRC cell lines resulted in chromosomal missegregation errors, and increased colony formation, and invasiveness, whereas BOP1 knockdown reduced viability. BOP1 promoted CIN by increasing the active form of aurora kinase B, which regulates chromosomal segregation. BOP1 was overexpressed in polyp tissues from CCAT2 transgenic mice compared with healthy tissue. CCAT2 lncRNA and BOP1 mRNA or protein were all increased in microsatellite stable tumors (characterized by CIN), but not in tumors with microsatellite instability compared with nontumor tissues. Increased levels of CCAT2 lncRNA and BOP1 mRNA correlated with each other and with shorter survival times of patients.CONCLUSIONS: We found that overexpression of CCAT2 in colon cells promotes CIN and carcinogenesis by stabilizing and inducing expression of BOP1 an activator of aurora kinase B. Strategies to target this pathway might be developed for treatment of patients with microsatellite stable colorectal tumors

Optimization of Multi-Port Empty Container Repositioning under Uncertain Environments

Empty container repositioning has always been an important problem faced by ports. In this paper, we study the multi-port empty container repositioning problem with the uncertainty of the demand and supply of empty containers in ports. First, we established an optimization model for empty container reposition strategies and calculated every port’s proportion, depending on its own empty container storage, on the operation of other ports and on the leasing company, in meeting the demand. Next, we established an optimization model for the empty container non-repositioning strategy, calculated the same proportions and compared their performance under two strategies. A two-stage particle swarm optimization (TS-PSO) algorithm was designed to solve the two models, and an example was used to verify the effectiveness of the algorithm and the rationality of the two models. Our research showed that the total cost of empty containers, storage costs, lease costs and the optimal storage of empty containers in ports under the repositioning strategy are all lower than those of the non-repositioning strategy. The proportion of the empty container demand met by inventory under the repositioning strategy is higher than that under the non-repositioning strategy, while the proportion of the empty container demand met by leasing is lower. The costs of leasing cost and repositioning empty containers are higher than those under the non-repositioning strategy. The increase in transportation time between ports per empty container mainly leads to the increase in the reposition costs of all ports. The increase in storage fees chiefly leads to the rising storage costs of all ports. The increase in leasing fees leads to the rising leasing costs of all ports. The paper provides a method for ports to decide the upper limit of empty container storage and to optimize their repositioning strategy

Optimization of Multi-Port Empty Container Repositioning under Uncertain Environments

Empty container repositioning has always been an important problem faced by ports. In this paper, we study the multi-port empty container repositioning problem with the uncertainty of the demand and supply of empty containers in ports. First, we established an optimization model for empty container reposition strategies and calculated every port’s proportion, depending on its own empty container storage, on the operation of other ports and on the leasing company, in meeting the demand. Next, we established an optimization model for the empty container non-repositioning strategy, calculated the same proportions and compared their performance under two strategies. A two-stage particle swarm optimization (TS-PSO) algorithm was designed to solve the two models, and an example was used to verify the effectiveness of the algorithm and the rationality of the two models. Our research showed that the total cost of empty containers, storage costs, lease costs and the optimal storage of empty containers in ports under the repositioning strategy are all lower than those of the non-repositioning strategy. The proportion of the empty container demand met by inventory under the repositioning strategy is higher than that under the non-repositioning strategy, while the proportion of the empty container demand met by leasing is lower. The costs of leasing cost and repositioning empty containers are higher than those under the non-repositioning strategy. The increase in transportation time between ports per empty container mainly leads to the increase in the reposition costs of all ports. The increase in storage fees chiefly leads to the rising storage costs of all ports. The increase in leasing fees leads to the rising leasing costs of all ports. The paper provides a method for ports to decide the upper limit of empty container storage and to optimize their repositioning strategy

A New Record of Orchidaceae from Guangxi: Galeola nudifolia Lour.

This paper reported a new record of Orchidaceae from Guangxi, Galeola nudifolia Lour. This species was previously known from Hainan Province and Yunnan Province of China, India, Myanmar, Vietnam, Thailand, Malaysia, Indonesia and the Philippines. The new Orchidaceae record has broken the record of only one species of the genus Galeola Lour. in Guangxi, and it filled the gap in the northern part of the original distribution area, and proved that the species in general is in a continuous distribution state. The new Orchidaceae record in Guangxi is of great significance to the study of the distribution pattern and geographical origin of the species

Transcriptomic Analysis of the Anthocyanin Biosynthetic Pathway Reveals the Molecular Mechanism Associated with Purple Color Formation in Dendrobium Nestor

Dendrobium nestor is a famous orchid species in the Orchidaceae family. There is a diversity of flower colorations in the Dendrobium species, but knowledge of the genes involved and molecular mechanism underlying the flower color formation in D. nestor is less studied. Therefore, we performed transcriptome profiling using Illumina sequencing to facilitate thorough studies of the purple color formation in petal samples collected at three developmental stages, namely—flower bud stage (F), half bloom stage (H), and full bloom stage (B) in D. nestor. In addition, we identified key genes and their biosynthetic pathways as well as the transcription factors (TFs) associated with purple flower color formation. We found that the phenylpropanoid–flavonoid–anthocyanin biosynthesis genes such as phenylalanine ammonia lyase, chalcone synthase, anthocyanidin synthase, and UDP-flavonoid glucosyl transferase, were largely up-regulated in the H and B samples as compared to the F samples. This upregulation might partly account for the accumulation of anthocyanins, which confer the purple coloration in these samples. We further identified several differentially expressed genes related to phytohormones such as auxin, ethylene, cytokinins, salicylic acid, brassinosteroid, and abscisic acid, as well as TFs such as MYB and bHLH, which might play important roles in color formation in D. nestor flower. Sturdy upregulation of anthocyanin biosynthetic structural genes might be a potential regulatory mechanism in purple color formation in D. nestor flowers. Several TFs were predicted to regulate the anthocyanin genes through a K-mean clustering analysis. Our study provides valuable resource for future studies to expand our understanding of flower color development mechanisms in D. nestor

Genome-wide association studies reveal the role of polymorphisms affecting factor H binding protein expression in host invasion by Neisseria meningitidis

Many invasive bacterial diseases are caused by organisms that are ordinarily harmless components of the human microbiome. Effective interventions against these microbes require an understanding of the processes whereby symbiotic or commensal relationships transition into pathology. Here, we describe bacterial genome-wide association studies (GWAS) of Neisseria meningitidis, a common commensal of the human respiratory tract that is nevertheless a leading cause of meningitis and sepsis. An initial GWAS discovered bacterial genetic variants, including single nucleotide polymorphisms (SNPs), associated with invasive meningococcal disease (IMD) versus carriage in several loci across the meningococcal genome, encoding antigens and other extracellular components, confirming the polygenic nature of the invasive phenotype. In particular, there was a significant peak of association around the fHbp locus, encoding factor H binding protein (fHbp), which promotes bacterial immune evasion of human complement by recruiting complement factor H (CFH) to the meningococcal surface. The association around fHbp with IMD was confirmed by a validation GWAS, and we found that the SNPs identified in the validation affected the 5' region of fHbp mRNA, altering secondary RNA structures, thereby increasing fHbp expression and enhancing bacterial escape from complement-mediated killing. This finding is consistent with the known link between complement deficiencies and CFH variation with human susceptibility to IMD. These observations demonstrate the importance of human and bacterial genetic variation across the fHbp:CFH interface in determining IMD susceptibility, the transition from carriage to disease