Prolactin receptor potentiates chemotherapy through miRNAs-induced G6PD/TKT inhibition in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with a notoriously dismal prognosis. As a competitive inhibitor of DNA synthesis, gemcitabine is the cornerstone drug for treating PDAC at all stages. The therapeutic effect of gemcitabine, however, is often hindered by drug resistance, and the underlying mechanisms remain largely unknown. It is unclear whether their response to chemotherapeutics is regulated by endocrine regulators, despite the association between PDAC risk and endocrine deregulation. Here, we show that prolactin receptor (PRLR) synergizes with gemcitabine in both in vitro and in vivo treatment of PDAC. Interestingly, PRLR promotes the expression of miR-4763-3p and miR-3663-5p, two novel miRNAs whose functions are unknown. Furthermore, the analysis of transcriptome sequencing data of tumors from lactating mouse models enriches the PPP pathway, a multifunctional metabolic pathway. In addition to providing energy, the PPP pathway mainly provides a variety of raw materials for anabolism. We demonstrate that two key enzymes of the pentose phosphate pathway (PPP), G6PD and TKT, are directly targeted by miR-4763-3p and miR-3663-5p. Notably, miR-4763-3p and miR-3663-5p diminish the nucleotide synthesis of the PPP pathway, thereby increasing gemcitabine sensitivity. As a result, PRLR harnesses these two miRNAs to suppress PPP and nucleotide synthesis, subsequently elevating the gemcitabine sensitivity of PDAC cells. Also, PDAC tissues and tumors from LSL-KrasG12D/+, LSL-Trp53R172H/+, and PDX1-cre (KPC) mice exhibit downregulation of PRLR. Bisulfite sequencing of PDAC tissues revealed that PRLR downregulation is due to epigenetic methylation. In this study, we show for the first time that the endocrine receptor PRLR improves the effects of gemcitabine by boosting two new miRNAs that block the PPP pathway and nucleotide synthesis by inhibiting two essential enzymes concurrently. The PRLR-miRNAs-PPP axis may serve as a possible therapeutic target to supplement chemotherapy advantages in PDAC.

Nucleolar HEAT Repeat Containing 1 Up-regulated by the Mechanistic Target of Rapamycin Complex 1 Signaling Promotes Hepatocellular Carcinoma Growth by Dominating Ribosome Biogenesis and Proteome Homeostasis.

BACKGROUND & AIMS: Hyperactivation of ribosome biogenesis leads to hepatocyte transformation and plays pivotal roles in hepatocellular carcinoma (HCC) development. We aimed to identify critical ribosome biogenesis proteins that are overexpressed and crucial in HCC progression. METHODS: HEAT repeat containing 1 (HEATR1) expression and clinical correlations were analyzed using The Cancer Genome Atlas and Gene Expression Omnibus databases and further evaluated by immunohistochemical analysis of an HCC tissue microarray. Gene expression was knocked down by small interfering RNA. HEATR1-knockdown cells were subjected to viability, cell cycle, and apoptosis assays and used to establish subcutaneous and orthotopic tumor models. Chromatin immunoprecipitation and quantitative polymerase chain reaction were performed to detect the association of candidate proteins with specific DNA sequences. Endogenous coimmunoprecipitation combined with mass spectrometry was used to identify protein interactions. We performed immunoblot and immunofluorescence assays to detect and localize proteins in cells. The nucleolus ultrastructure was detected by transmission electron microscopy. Click-iT (Thermo Fisher Scientific) RNA imaging and puromycin incorporation assays were used to measure nascent ribosomal RNA and protein synthesis, respectively. Proteasome activity, 20S proteasome foci formation, and protein stability were evaluated in HEATR1-knockdown HCC cells. RESULTS: HEATR1 was the most up-regulated gene in a set of ribosome biogenesis mediators in HCC samples. High expression of HEATR1 was associated with poor survival and malignant clinicopathologic features in patients with HCC and contributed to HCC growth in vitro and in vivo. HEATR1 expression was regulated by the transcription factor specificity protein 1, which can be activated by insulin-like growth factor 1-mammalian target of rapamycin complex 1 signaling in HCC cells. HEATR1 localized predominantly in the nucleolus, bound to ribosomal DNA, and was associated with RNA polymerase I transcription/processing factors. Knockdown of HEATR1 disrupted ribosomal RNA biogenesis and impaired nascent protein synthesis, leading to reduced cytoplasmic proteasome activity and inhibitory-κB/nuclear factor-κB signaling. Moreover, HEATR1 knockdown induced nucleolar stress with increased nuclear proteasome activity and inactivation of the nucleophosmin 1-MYC axis. CONCLUSIONS: Our study revealed that HEATR1 is up-regulated by insulin-like growth factor 1-mammalian target of rapamycin complex 1-specificity protein 1 signaling in HCC and functions as a crucial regulator of ribosome biogenesis and proteome homeostasis to promote HCC development.

Waterborne Polyurethane Micelles Reinforce PEO-Based Electrolytes for Lithium Metal Batteries.

Although solid polymer electrolytes have been developed for several decades, poly(ethylene oxide) (PEO) or polymers with ethoxy (EO) segments are still one of the most promising candidates for advanced batteries. The low ionic conductivity and lithium-ion transference number as well as the deterioration of mechanical properties after coupling with lithium salts restrict its further adoption. Herein, a serial of PEO-based composite electrolytes optimized by waterborne polyurethane are prepared via blend method. With the assistance of H2O, ionic type waterborne polyurethane assembles into flexible micelles, in which hydrophobic segments as the core and hydrophilic groups as the shell. Utilizing this feature of waterborne polyurethane, PEO and Li salt (LiTFSI) aqueous solution is slowly added to the organic solution of waterborne polyurethane to compound in situ, and polymer composite electrolytes are fabricated. The multilevel (hydrogen bonds with different binding energy) and multiscale (deformation of flexible micelles) dynamic interaction endows the composite electrolyte with attractive mechanical properties. The assembled Li|Li symmetric battery with the molar ratio of EO to Li salts of 8:1 exhibits excellent cycling stability up to 800 h at 0.1 mA cm-2, and the assembled Li|LiFePO4 battery can be stably cycled at 1C for >400 cycles.

Roles of histone post-translational modifications in meiosis†.

Histone post-translational modifications, such as phosphorylation, methylation, acetylation, and ubiquitination, play vital roles in various chromatin-based cellular processes. Meiosis is crucial for organisms that depend on sexual reproduction to produce haploid gametes, during which chromatin undergoes intricate conformational changes. An increasing body of evidence is clarifying the essential roles of histone post-translational modifications during meiotic divisions. In this review, we concentrate on the post-translational modifications of H2A, H2B, H3, and H4, as well as the linker histone H1, that are required for meiosis, and summarize recent progress in understanding how these modifications influence diverse meiotic events. Finally, challenges and exciting open questions for future research in this field are discussed. Summary Sentence  Diverse histone post-translational modifications exert important effects on the meiotic cell cycle and these "histone codes" in meiosis might lead to the development of novel therapeutic strategies against reproductive diseases.

Discovery of a Potent, selective and orally bioavailable CDK9 degrader for targeting transcription regulation in Triple-Negative breast cancer.

Triple-negative breast cancer (TNBC) is a highly aggressive, heterogeneous and invasive subtype of breast cancer with very limited effective modalities of treatment. Degrading the critical transcription regulator cyclin-dependent kinase 9 (CDK9) by proteolysis targeting chimeras (PROTACs) has shown promising potential for treating TNBC. However, to date, CDK9-targeting PROTACs for oral administration in treatment of cancers have not been reported. We herein present the design, synthesis, and extensive biological evaluation of a series of novel PROTACs as orally bioavailable, potent and selective degraders of CDK9 for targeting transcription regulation in triple-negative breast cancer. The developed compound 29 exhibited a desired potency (DC50 = 3.94 nM) with high efficacy (Dmax = 96 %) on CDK9 degradation, and effectively inhibited the proliferation of TNBC MDA-MB-231 cells. Mechanistic investigations revealed that compound 29 is a bona fide CDK9 degrader and can substantially downregulate the downstream targets c-Myc and MCL-1. Furthermore, compound 29 displayed favorable oral bioavailability in mice, and oral administration of degrader 29 significantly depleted CDK9 protein in TNBC tumor tissues and exhibited tumor growth inhibition in TNBC xenograft mice models. Collectively, our work established that degrader 29 is a highly potent and selective degraders of CDK9 with satisfactory oral bioavailability, which holds promising potential for the treatment of TNBC.

Tumor-targeted PROTAC prodrug nanoplatform enables precise protein degradation and combination cancer therapy.

Proteolysis targeting chimeras (PROTACs) have emerged as revolutionary anticancer therapeutics that degrade disease-causing proteins. However, the anticancer performance of PROTACs is often impaired by their insufficient bioavailability, unsatisfactory tumor specificity and ability to induce acquired drug resistance. Herein, we propose a polymer-conjugated PROTAC prodrug platform for the tumor-targeted delivery of the most prevalent von Hippel-Lindau (VHL)- and cereblon (CRBN)-based PROTACs, as well as for the precise codelivery of a degrader and conventional small-molecule drugs. The self-assembling PROTAC prodrug nanoparticles (NPs) can specifically target and be activated inside tumor cells to release the free PROTAC for precise protein degradation. The PROTAC prodrug NPs caused more efficient regression of MDA-MB-231 breast tumors in a mouse model by degrading bromodomain-containing protein 4 (BRD4) or cyclin-dependent kinase 9 (CDK9) with decreased systemic toxicity. In addition, we demonstrated that the PROTAC prodrug NPs can serve as a versatile platform for the codelivery of a PROTAC and chemotherapeutics for enhanced anticancer efficiency and combination benefits. This study paves the way for utilizing tumor-targeted protein degradation for precise anticancer therapy and the effective combination treatment of complex diseases.

Negative supercoils regulate meiotic crossover patterns in budding yeast.

Interference exists ubiquitously in many biological processes. Crossover interference patterns meiotic crossovers, which are required for faithful chromosome segregation and evolutionary adaption. However, what the interference signal is and how it is generated and regulated is unknown. We show that yeast top2 alleles which cannot bind or cleave DNA accumulate a higher level of negative supercoils and show weaker interference. However, top2 alleles which cannot religate the cleaved DNA or release the religated DNA accumulate less negative supercoils and show stronger interference. Moreover, the level of negative supercoils is negatively correlated with crossover interference strength. Furthermore, negative supercoils preferentially enrich at crossover-associated Zip3 regions before the formation of meiotic DNA double-strand breaks, and regions with more negative supercoils tend to have more Zip3. Additionally, the strength of crossover interference and homeostasis change coordinately in mutants. These findings suggest that the accumulation and relief of negative supercoils pattern meiotic crossovers.

Low levels of Cd2+ combined with procymidone may cause ovarian damage in mice via unfolded protein response.

As no study about the combined effect of low levels of Cd2+ with procymidone (PCM) on organs and organisms, we investigated their actions on mouse-ovary in vivo and in vitro. Four-week mice were treated with corn oil for the control group, corn oil + 0.0045 mg/L Cd2+ (CdCl2 was dissolved in ultrapure water and freely consumed by mice) for Cd2+ group, 50 mg/kg/d PCM (suspended in corn oil and administered orally to mice) for PCM group, and 50 mg/kg/d PCM + 0.0015 (0.0045 and 0.0135) mg/L Cd2+ for L+ (M+ and H+) PCM group for 21 days. For in vitro experiment, the cultured ovaries were treated with acetone for the control group, 0.1% acetone + 8.4 µg/L Cd2+ for the Cd2+ group, 0.63 mg/L PCM (dissolved in acetone) for the PCM-group, and 0.63 mg/L PCM + 2.8 (8.4 and 25.2) µg/L Cd2+ for L+ (M+ and H+) PCM group for 7 days. Mouse body weight in each treatment group, the weight and volume of ovaries in all PCM groups were lower than the control. Both in vivo and in vitro, all-stage follicle numbers were lower in M+PCM and H+PCM groups, whereas the atretic follicles and CASPASE3/8 were higher; meanwhile, lower estradiol and progesterone and higher unfolded protein response (UPR) members in all PCM groups. L+, M+, and H+PCM groups had further ovarian damage and stronger UPR than PCM groups, as did M+PCM groups over Cd2+ groups. It is hypothesized low-level PCM and Cd2+ may mutually promote each other's triggered UPR and exacerbate ovarian damage.

Microbial inoculants using spent mushroom substrates as carriers improve soil multifunctionality and plant growth by changing soil microbial community structure.

Peat is typically used as a carrier for microbial inoculants; however, due to its non-renewable nature alternatives need to be identified as reliable and renewable carriers for mineral-solubilizing inoculants. In pot experiments, solid microbial inoculants were comprised of peat (P), biochar (BC), and spent mushroom substrates (SMS) using Medicago sativa L. as experimental materials, and the purpose of this study is to assess the effect of solid microbial inoculants on soil multifunctionality and plant growth. The results revealed that the SMS microbial inoculant had the greatest positive impact on plant biomass and significantly stimulated soil multifunctionality which is typically managed or assessed based on various soil functions or processes that are crucial for sustaining productivity, in contrast to the peat microbial inoculant, particularly at a supply level of 100 g/pot. There was no significant correlation between soil multifunctionality and bacterial/fungal microbial diversity. However, according to the co-occurrence network of bacteria and fungi, soil multifunctionality was intimately correlated with the biodiversity of the main ecological clusters (modules) of bacteria and fungi, rather than to the entire soil microbial community structure. The keystone species of module hubs and connectors play critical roles in maintaining the stability of ecological clusters of microbial co-occurrence networks and linkages between ecological clusters. Soil pH is a major predictor of changes in plant biomass, and leads to changes therein by affecting the major ecological clusters of bacterial and fungal co-occurrence networks. These results suggested that SMS may serve as a good alternative to peat as a carrier of mineral-solubilizing microorganisms to maintain soil multifunctionality and promote plant growth.

Terbinafine prevents colorectal cancer growth by inducing dNTP starvation and reducing immune suppression.

Existing evidence indicates that gut fungal dysbiosis might play a key role in the pathogenesis of colorectal cancer (CRC). We sought to explore whether reversing the fungal dysbiosis by terbinafine, an approved antifungal drug, might inhibit the development of CRC. A population-based study from Sweden identified a total of 185 patients who received terbinafine after their CRC diagnosis and found that they had a decreased risk of death (hazard ratio = 0.50) and metastasis (hazard ratio = 0.44) compared with patients without terbinafine administration. In multiple mouse models of CRC, administration of terbinafine decreased the fungal load, the fungus-induced myeloid-derived suppressor cell (MDSC) expansion, and the tumor burden. Fecal microbiota transplantation from mice without terbinafine treatment reversed MDSC infiltration and partially restored tumor proliferation. Mechanistically, terbinafine directly impaired tumor cell proliferation by reducing the ratio of nicotinamide adenine dinucleotide phosphate (NADP+) to reduced form of nicotinamide adenine dinucleotide phosphate (NADPH), suppressing the activity of glucose-6-phosphate dehydrogenase (G6PD), resulting in nucleotide synthesis disruption, deoxyribonucleotide (dNTP) starvation, and cell-cycle arrest. Collectively, terbinafine can inhibit CRC by reversing fungal dysbiosis, suppressing tumor cell proliferation, inhibiting fungus-induced MDSC infiltration, and restoring antitumor immune response.

Mineral-solubilizing microbial inoculant positively affects the multifunctionality of anthropogenic soils in abandoned mining areas.

The mining industry has a significant negative impact on ecosystems, and the remediation of abandoned mining sites requires effective strategies. One promising approach is the incorporation of mineral-solubilizing microorganisms into current external soil spray seeding technologies. These microorganisms possess the ability to decrease mineral particle sizes, promote plant growth, and enhance the release of vital soil nutrients. However, most previous studies on mineral-solubilizing microorganisms have been conducted in controlled greenhouse environments, and their practical application in field settings remains uncertain. To address this knowledge gap, we conducted a four-year field experiment at an abandoned mining site to investigate the efficacy of mineral-solubilizing microbial inoculants in restoring derelict mine ecosystems. We assessed soil nutrients, enzyme activities, functional genes, and soil multifunctionality. We also examined microbial compositions, co-occurrence networks, and community assembly processes. Our results demonstrated that the application of mineral-solubilizing microbial inoculants significantly enhanced soil multifunctionality. Interestingly, certain bacterial phyla or class taxa with low relative abundances were found to be key drivers of multifunctionality. Surprisingly, we observed no significant correlation between microbial alpha diversity and soil multifunctionality, but we did identify positive associations between the relative abundance and biodiversity of keystone ecological clusters (Module #1 and #2) and soil multifunctionality. Co-occurrence network analysis revealed that microbial inoculants reduced network complexity while increasing stability. Additionally, we found that stochastic processes played a predominant role in shaping bacterial and fungal communities, and the inoculants increased the stochastic ratio of microbial communities, particularly bacteria. Moreover, microbial inoculants significantly decreased the relative importance of dispersal limitations and increased the relative importance of drift. High relative abundances of certain bacterial and fungal phyla were identified as major drivers of the microbial community assembly process. In conclusion, our findings highlight the crucial role of mineral-solubilizing microorganisms in soil restoration at abandoned mining sites, shedding light on their significance in future research endeavors focused on optimizing the effectiveness of external soil spray seeding techniques.

Meiotic chromosome organization and crossover patterns†.

Meiosis is the foundation of sexual reproduction, and crossover recombination is one hallmark of meiosis. Crossovers establish the physical connections between homolog chromosomes (homologs) for their proper segregation and exchange DNA between homologs to promote genetic diversity in gametes and thus progenies. Aberrant crossover patterns, e.g., absence of the obligatory crossover, are the leading cause of infertility, miscarriage, and congenital disease. Therefore, crossover patterns have to be tightly controlled. During meiosis, loop/axis organized chromosomes provide the structural basis and regulatory machinery for crossover patterning. Accumulating evidence shows that chromosome axis length regulates the numbers and the positions of crossovers. In addition, recent studies suggest that alterations in axis length and the resultant alterations in crossover frequency may contribute to evolutionary adaptation. Here, current advances regarding these issues are reviewed, the possible mechanisms for axis length regulating crossover frequency are discussed, and important issues that need further investigations are suggested.

MoS2 Decorated Silver Nanowire-Reduced Graphene Oxide Aerogel Micro-Particle for Thermally Conductive Polymer Composites with Enhanced Flame Retardancy.

Multifunctional polymer composites with efficient heat dissipation and flame retardancy are highly desirable in the electronic industry. Here, by the combination of hydrothermal reaction and in situ fragmentation, molybdenum disulfide (MoS2 ) decorated silver nanowires (AgNWs) and 3D reduced graphene oxide (RGO) (AgNW-RGO@MoS2 ) aerogel micro-particles (AMPs) are successfully prepared. When the above AMP is introduced to epoxy (EP) resin by the simple blending method, a polymer composite with continuous thermally conductive pathways and flame barrier layers is achieved. With an AMP loading of 4.0 vol.%, the polymer composite displays superior enhancement in thermal conductivity up to 420%. Compared to neat EP, the peak heat release rate and total heat release decreases by 61.1% and 58.8%, respectively. This work provides new insights into the design and large-scale fabrication of multifunctional polymer composites for efficient thermal management materials.

Light-Switchable and Self-Healable Polymer Electrolytes Based on Dynamic Diarylethene and Metal-Ion Coordination.

Self-healing polymer electrolytes are reported with light-switchable conductivity based on dynamic N-donor ligand-containing diarylethene (DAE) and multivalent Ni2+ metal-ion coordination. Specifically, a polystyrene polymer grafted with poly(ethylene glycol-r-DAE)acrylate copolymer side chains was effectively cross-linked with nickel(II) bis(trifluoromethanesulfonimide) (Ni(TFSI)2) salts to form a dynamic network capable of self-healing with fast exchange kinetics under mild conditions. Furthermore, as a photoswitching compound, the DAE undergoes a reversible structural and electronic rearrangement that changes the binding strength of the DAE-Ni2+ complex under irradiation. This can be observed in the DAE-containing polymer electrolyte where irradiation with UV light triggers an increase in the resistance of solid films, which can be recovered with subsequent visible light irradiation. The increase in resistance under UV light irradiation indicates a decrease in ion mobility after photoswitching, which is consistent with the stronger binding strength of ring-closed DAE isomers with Ni2+. 1H-15N heteronuclear multiple-bond correlation nuclear magnetic resonance (HMBC NMR) spectroscopy, continuous wave electron paramagnetic resonance (cw EPR) spectroscopy, and density functional theory (DFT) calculations confirm the increase in binding strength between ring-closed DAE with metals. Rheological and in situ ion conductivity measurements show that these polymer electrolytes efficiently heal to recover their mechanical properties and ion conductivity after damage, illustrating potential applications in smart electronics.

The clinical significance of remnant thyroid tissue in thyroidectomized differentiated thyroid cancer patients on 131I-SPECT/CT.

BACKGROUND: To explore the 131I-SPECT/CT characteristics of remnant thyroid tissue (RTT) in differentiated thyroid cancer (DTC), further assess the risk factors and clinical significance. METHODS: 52 DTC patients after total thyroidectomy had undergone neck 131I-SPECT/CT before 131I ablation. The diagnosis of RTT was based on SPECT/CT and follow-up at least 3 months. The anatomic locations and features of SPECT/CT of RTT were assessed by reviewers. The risk factors of RTT with CT positive were analyzed by the chi-square test. RESULTS: A total of 80 lesions of RTT were diagnosed in this study, most of them were mainly located in the regions adjacent to trachea cartilage (37/80) or lamina of thyroid cartilage (17/80). On SPECT/CT of RTT, low, moderate and high uptake were respectively noted in 10, 24 and 46 lesions, definite positive, suspected positive and negative CT findings were respectively noted in 10, 21 and 49. The RTT lesions with definite positive CT findings were mainly located adjacent to lamina of thyroid cartilage (5/10). Primary thyroid tumor (P = 0.029) and T stage (P = 0.000) were the effective risk factors of CT positive RTT. CONCLUSIONS: RTT has certain characteristic distribution and appearances on SPECT/CT. Most of RTT with definite CT abnormalities located adjacent to lamina of thyroid cartilage, which suggest surgeons should strengthen the careful removal in this region, especially primary thyroid tumor involving bilateral and T4 stage. This study can provide a certain value for the improvement of thyroidectomy quality in DTC patients.

Light-Controllable Ionic Conductivity in a Polymeric Ionic Liquid.

Polymeric ionic liquids (PILs) have attracted considerable attention as electrolytes with high stability and mechanical durability. Light-responsive materials are enabling for a variety of future technologies owing to their remote and noninvasive manipulation, spatiotemporal control, and low environmental impact. To address this potential, responsive PIL materials based on diarylethene units were designed to undergo light-mediated conductivity changes. Key to this modulation is tuning of the cationic character of the imidazolium bridging unit upon photoswitching. Irradiation of these materials with UV light triggers a circa 70 % drop in conductivity in the solid state that can be recovered upon subsequent irradiation with visible light. This light-responsive ionic conductivity enables spatiotemporal and reversible patterning of PIL films using light. This modulation of ionic conductivity allows for the development of light-controlled electrical circuits and wearable photodetectors.

GABRP regulates chemokine signalling, macrophage recruitment and tumour progression in pancreatic cancer through tuning KCNN4-mediated Ca2+ signalling in a GABA-independent manner.

BACKGROUND AND AIMS: Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related death worldwide. Neurotransmitter-initiated signalling pathway is profoundly implicated in tumour initiation and progression. Here, we investigated whether dysregulated neurotransmitter receptors play a role during pancreatic tumourigenesis. METHODS: The Cancer Genome Atlas and Gene Expression Omnibus datasets were used to identify differentially expressed neurotransmitter receptors. The expression pattern of gamma-aminobutyric acid type A receptor pi subunit (GABRP) in human and mouse PDAC tissues and cells was studied by immunohistochemistry and western blot analysis. The in vivo implications of GABRP in PDAC were tested by subcutaneous xenograft model and lung metastasis model. Bioinformatics analysis, transwell experiment and orthotopic xenograft model were used to identify the in vitro and in vivo effects of GABRP on macrophages in PDAC. ELISA, co-immunoprecipitation, proximity ligation assay, electrophysiology, promoter luciferase activity and quantitative real-time PCR analyses were used to identify molecular mechanism. RESULTS: GABRP expression was remarkably increased in PDAC tissues and associated with poor prognosis, contributed to tumour growth and metastasis. GABRP was correlated with macrophage infiltration in PDAC and pharmacological deletion of macrophages largely abrogated the oncogenic functions of GABRP in PDAC. Mechanistically, GABRP interacted with KCNN4 to induce Ca2+ entry, which leads to activation of nuclear factor κB signalling and ultimately facilitates macrophage infiltration by inducing CXCL5 and CCL20 expression. CONCLUSIONS: Overexpressed GABRP exhibits an immunomodulatory role in PDAC in a neurotransmitter-independent manner. Targeting GABRP or its interaction partner KCNN4 may be an effective therapeutic strategy for PDAC.

Identification of differentially expressed genes and functional annotations associated with metastases of the uveal melanoma.

Uveal melanoma (UVM) is an adult intraocular malignancy which is the most frequent and has a high tendency for metastasis. This study aims to develop significant differential gene subnetwork between primary and metastatic UVM to identify potential prognostic biomarkers. Differentially expressed genes (DEGs) among three chip datasets were downloaded from Gene Expression Omnibus and identified according to standardization annotation information. Genetic enrichment analyses were utilized to describe biologic functions. The protein-protein interaction network of DEGs was developed and the module analysis was constructed by STRING and Cytoscape. Kaplan-Meier method of the integrated expression score was applied to analyze survival outcomes. Functional annotation was assessed to perform GO and Kyoto Encyclopedia of Genes and Genomes enrichment analysis. In addition, ClueGO and gene set enrichment analysis were analyzed to detect underlying significant genes and involved signaling pathways. A total of 103 DEGs with function enrichment were recognized and might be considered as candidate prognostic biomarkers between primary and metastatic UVM. Furthermore, Kaplan-Meier method suggested that SCD5, SPTBN1, FABP5, SQLE, PTPLA (HACD1), and CDC25B were independent prognostic factors in UVM. Functional annotations indicated that the most involved significant pathways including interferon-gamma response, IL-6 JAK STAT3 signaling, TNFA signaling via NFKB and inflammatory response. Significant DEGs between primary and metastatic UVM tissue were identified and might have involved in the metastasis of UVM. SCD5, SPTBN1, FABP5, SQLE, PTPLA (HACD1), and CDC25B transcription levels were of high prognostic value, which might assist us to understand the underlying carcinogenesis or advancement of UVM better.

Overexpression of Rac GTPase Activating Protein 1 Contributes to Proliferation of Cancer Cells by Reducing Hippo Signaling to Promote Cytokinesis.

BACKGROUND & AIMS: Agents designed to block or alter cytokinesis can kill or stop proliferation of cancer cells. We aimed to identify cytokinesis-related proteins that are overexpressed in hepatocellular carcinoma (HCC) cells and might be targeted to slow liver tumor growth. METHODS: Using the Oncomine database, we compared the gene expression patterns in 16 cancer microarray datasets and assessed gene enrichment sets using gene ontology. We performed immunohistochemical analysis of an HCC tissue microarray and identified changes in protein levels that are associated with patient survival times. Candidate genes were overexpressed or knocked down with small hairpin RNAs in SMMC7721, MHCC97H, or HCCLM3 cell lines; we analyzed their proliferation, viability, and clone-formation ability and their growth as subcutaneous or orthotopic xenograft tumors in mice. We performed microarray analyses to identify alterations in signaling pathways and immunoblot and immunofluorescence assays to detect and localize proteins in tissues. Yeast 2-hybrid screens and mass spectrometry combined with co-immunoprecipitation experiments were used to identify binding proteins. Protein interactions were validated with co-immunoprecipitation and proximity ligation assays. Chromatin immunoprecipitation, promoter luciferase activity, and quantitative real-time polymerase chain reaction analyses were used to identify factors that regulate transcription of specific genes. RESULTS: The genes that were most frequently overexpressed in different types of cancer cells were involved in cell division processes. We identified 3 cytokinesis-regulatory proteins among the 10 genes most frequently overexpressed by all cancer cell types. Rac GTPase activating protein 1 (RACGAP1) was the cytokinesis-regulatory protein that was most highly overexpressed in multiple cancers. Increased expression of RACGAP1 in tumor tissues was associated with shorter survival times of patients with cancer. Knockdown of RACGAP1 in HCC cells induced cytokinesis failure and cell apoptosis. In microarray analyses, we found knockdown of RACGAP1 in SMMC7721 cells to reduce expression of genes regulated by yes-associated protein (YAP) and WW domain containing transcription regulator 1 (WWTR1 or TAZ). RACGAP1 reduced activation of the Hippo pathway in HCC cells by increasing activity of RhoA and polymerization of filamentous actin. Knockdown of YAP reduced phosphorylation of RACGAP1 and redistribution at the anaphase central spindle. We found transcription of the translocated promoter region, nuclear basket protein (TPR) to be regulated by YAP and coordinately expressed with RACGAP1 to promote proliferation of HCC cells. TPR redistributed upon nuclear envelope breakdown and formed complexes with RACGAP1 during mitosis. Knockdown of TPR in HCC cells reduced phosphorylation of RACGAP1 by aurora kinase B and impaired their redistribution at the central spindle during cytokinesis. STAT3 activated transcription of RACGAP in HCC cells. CONCLUSIONS: In an analysis of gene expression patterns of multiple tumor types, we found RACGAP1 to be frequently overexpressed, which is associated with shorter survival times of patients. RACGAP1 promotes proliferation of HCC cells by reducing activation of the Hippo and YAP pathways and promoting cytokinesis in coordination with TPR.

Alternative transcription start site selection in ACSS2 controls its nuclear localization and promotes ribosome biosynthesis in hepatocellular carcinoma.

Acetyl-CoA synthetase 2 (ACSS2) generates acetyl-CoA from acetate is important for histone acetylation and gene expression. ACSS2 fulfills distinct functions depending on its cellular location in tumor cells. The role and cellular localization of ACSS2 in hepatocellular carcinoma (HCC) remains to be studied. Herein, we identified that the alternative transcription start site selection of ACSS2 was significantly different between HCC and corresponding adjacent tissues. Alternative transcription start site selection produced two different ACSS2 transcripts, ACSS2-S1 and ACSS2-S2. The two isoforms of ACSS2 had different subcellular localization and different functions. Overexpression of ACSS2-S2 promoted cell proliferation and invasion, but ACSS2-S1 did not. The ACSS2-S1 was mainly present in cytoplasm, and ACSS2-S2 was distributed in both nucleus and cytoplasm. Finally, we demonstrated that alternative transcription start site selection of ACSS2 correlates ribosome biogenesis in HCC. Our findings reveal an oncogenic role of ACSS2-S2 in HCC progression via increase of ribosome biogenesis, and suggest ACSS2-S2 might be a potential therapeutic target against the HCC.