Complex Interactions between Cohesin and CTCF in Regulation of Kaposi's Sarcoma-Associated Herpesvirus Lytic Transcription.

CTCF and the cohesin complex modify chromatin by binding to DNA and interacting with each other and with other cellular proteins. Both proteins regulate transcription by a variety of local effects on transcription and by long-range topological effects. CTCF and cohesin also bind to herpesvirus genomes at specific sites and regulate viral transcription during latent and lytic cycles of replication. Kaposi's sarcoma-associated herpesvirus (KSHV) transcription is regulated by CTCF and cohesin, with both proteins previously reported to act as restrictive factors for lytic cycle transcription and virion production. In this study, we examined the interdependence of CTCF and cohesin binding to the KSHV genome. Chromatin immunoprecipitation sequencing (ChIP-seq) analyses revealed that cohesin binding to the KSHV genome is highly CTCF dependent, whereas CTCF binding does not require cohesin. Furthermore, depletion of CTCF leads to the almost complete dissociation of cohesin from sites at which they colocalize. Thus, previous studies that examined the effects of CTCF depletion actually represent the concomitant depletion of both CTCF and cohesin components. Analysis of the effects of single and combined depletion indicates that CTCF primarily activates KSHV lytic transcription, whereas cohesin has primarily inhibitory effects. Furthermore, CTCF or cohesin depletion was found to have regulatory effects on cellular gene expression relevant for the control of viral infection, with both proteins potentially facilitating the expression of multiple genes important in the innate immune response to viruses. Thus, CTCF and cohesin have both positive and negative effects on KSHV lytic replication as well as effects on the host cell that enhance antiviral defenses.IMPORTANCE Kaposi's sarcoma-associated herpesvirus (KSHV) is causally linked to Kaposi's sarcoma and several lymphoproliferative diseases. KSHV, like other herpesviruses, intermittently reactivates from latency and enters a lytic cycle in which numerous lytic mRNAs and proteins are produced, culminating in infectious virion production. These lytic proteins may also contribute to tumorigenesis. Reactivation from latency is controlled by processes that restrict or activate the transcription of KSHV lytic genes. KSHV gene expression is modulated by binding of the host cell proteins CTCF and cohesin complex to the KSHV genome. These proteins bind to and modulate the conformation of chromatin, thereby regulating transcription. We have analyzed the interdependence of binding of CTCF and cohesin and demonstrate that while CTCF is required for cohesin binding to KSHV, they have very distinct effects, with cohesin primarily restricting KSHV lytic transcription. Furthermore, we show that cohesin and CTCF also exert effects on the host cell that promote antiviral defenses.

Human IFIT proteins inhibit lytic replication of KSHV: A new feed-forward loop in the innate immune system.

Kaposi's sarcoma-associated herpesvirus (KSHV) is causally associated with Kaposi's sarcoma, primary effusion lymphoma (PEL) and multicentric Castleman's disease. The IFIT family of proteins inhibits replication of some viruses, but their effects on KSHV lytic replication was unknown. Here we show that KSHV lytic replication induces IFIT expression in epithelial cells. Depletion of IFIT1, IFIT2 and IFIT3 (IFITs) increased infectious KSHV virion production 25-32-fold compared to that in control cells. KSHV lytic gene expression was upregulated broadly with preferential activation of several genes involved in lytic viral replication. Intracellular KSHV genome numbers were also increased by IFIT knockdown, consistent with inhibition of KSHV DNA replication by IFITs. RNA seq demonstrated that IFIT depletion also led to downregulation of IFN ß and several interferon-stimulated genes (ISGs), especially OAS proteins. OAS down-regulation led to decreased RNase L activity and slightly increased total RNA yield. IFIT immunoprecipitation also showed that IFIT1 bound to viral mRNAs and cellular capped mRNAs but not to uncapped RNA or trimethylated RNAs, suggesting that IFIT1 may also inhibit viral mRNA expression through direct binding. In summary, IFIT inhibits KSHV lytic replication through positively regulating the IFN ß and OAS RNase L pathway to degrade RNA in addition to possibly directly targeting viral mRNAs.

Continuous DNA replication is required for late gene transcription and maintenance of replication compartments in gammaherpesviruses.

Late gene transcription in herpesviruses is dependent on viral DNA replication in cis but the mechanistic basis for this linkage remains unknown. DNA replication results in demethylated DNA, topological changes, removal of proteins and recruitment of proteins to promoters. One or more of these effects of DNA replication may facilitate late gene transcription. Using 5-azacytidine to promote demethylation of DNA, we demonstrate that late gene transcription cannot be rescued by DNA demethylation. Late gene transcription precedes significant increases in DNA copy number, indicating that increased template numbers also do not contribute to the linkage between replication and late gene transcription. By using serial, timed blockade of DNA replication and measurement of late gene mRNA accumulation, we demonstrate that late gene transcription requires ongoing DNA replication. Consistent with these findings, blocking DNA replication led to dissolution of DNA replication complexes which also contain RNA polymerase II and BGLF4, an EBV protein required for transcription of several late genes. These data indicate that ongoing DNA replication maintains integrity of a replication-transcription complex which is required for recruitment and retention of factors necessary for late gene transcription.

Impact of body mass index on postoperative outcomes in patients undergoing radical resection for hilar cholangiocarcinoma.

BACKGROUND: Body mass index (BMI) has been widely used as a prognostic indicator. The association between preoperative BMI and postoperative morbidity in patients with hilar cholangiocarcinoma (HCCA) has not been proved. This study aimed to identify the association between preoperative BMI and postoperative morbidity following radical resection of HCCA. METHODS: Patients were divided into three groups according to preoperative BMI: low BMI (≤18.4 kg/m2 ), normal BMI (18.4-24.9 kg/m2 ), and high BMI (≥24.9 kg/m2 ). Baseline characteristics, operative variables, postoperative 30-day mortality, and morbidity were compared. Risk factors associated with postoperative morbidity were assessed using univariable and multivariable logistic analyses. RESULTS: Among 260 patients, 183 (70.4%) had normal BMI, 32 (12.3%) had low BMI, and 45 (17.3%) had high BMI. Compared to the patients with normal-BMI, both low and high BMI patients exhibited a significantly higher postoperative morbidity (87.5% and 82.2% vs 63.9%, P = .019 and P = .025, respectively). Additionally, the multivariable analysis revealed that both low and high BMI patients remained independently associated with an increased risk of postoperative morbidity. (OR: 3.707, 95% CI: 1.080-12.725, P = .037; and OR: 2.858, 95% CI: 1.167-7.002, P = .022, respectively). CONCLUSION: BMI is an independent risk factor for higher postoperative morbidity in patients who undergo surgical treatment of hilar cholangiocarcinoma.

Telemedicine During the COVID-19 Pandemic: Experiences From Western China.

Disasters and pandemics pose unique challenges to health care delivery. As health care resources continue to be stretched due to the increasing burden of the coronavirus disease (COVID-19) pandemic, telemedicine, including tele-education, may be an effective way to rationally allocate medical resources. During the COVID-19 pandemic, a multimodal telemedicine network in Sichuan Province in Western China was activated immediately after the first outbreak in January 2020. The network synergizes a newly established 5G service, a smartphone app, and an existing telemedicine system. Telemedicine was demonstrated to be feasible, acceptable, and effective in Western China, and allowed for significant improvements in health care outcomes. The success of telemedicine here may be a useful reference for other parts of the world.

[Diagnostic Value of Abnormal Prothrombin in HBV-related AFP-negative Hepatocellular Carcinoma].

OBJECTIVE: To evaluate the diagnostic value of abnormal prothrombin (DCP) in Alpha-fetoproteins (AFP)-negative (AFP≤20 ng/mL) hepatocellular carcinoma and the relationship between DCP level and Child-Pugh grade, tumor size, TNM stage as well as differentiation. METHODS: The inpatients diagnosed with hepatitis B-related liver disease were collected from June 2016 to December 2017, The diagnostic efficacy of DCP for AFP-negative HCC was analyzed by ROC. Area under the curve ( AUC), the best cut point, sensitivity, specificity, positive predictive value and negative predictive value were calculated. The relationship between DCP levels and the clinical characteristic of HCC was analyzed. RESULTS: A total of 459 hepatitis B markers positive patients were included, including 136 cases of hepatocellular carcinoma, 173 cases of hepatitis B cirrhosis and 150 cases of chronic hepatitis B. DCP in AFP-negative hepatocellular carcinoma group was significantly higher than that in non-HCC group (CHB and LC) ( P<0.05). The AUC of DCP was 0.858, P<0.05. The optimal cut-off point for the diagnosis of hepatocellular carcinoma was 61 mAU/mL. The corresponding sensitivity, specificity, positive predictive value and negative predictive value were 72.8%, 88.2%, 61.1% and 89.7%, respectively. In different size of hepatocellular carcinoma, DCP level of those with diameter>3 cm was significantly higher than those with diameter≤3 cm ( P<0.05). In different TNM stages, DCP level in stage Ⅱ and Ⅲ was significantly higher than that in stage Ⅰ ( P<0.05). There was no significant difference of DCP level among different Child-Pugh grades and differentiation ( P>0.05). CONCLUSION: DCP has diagnostic value for AFP-negative hepatocellular carcinoma, its level may reflects the degree of tumor progression.

Reconstruction and Analysis of the Differentially Expressed IncRNA-miRNA-mRNA Network Based on Competitive Endogenous RNA in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a common and aggressive malignant neoplasm with an increasing incidence rate among cancers worldwide. This study aimed to establish a competing-endogenous RNA (ceRNA) network to further understand the ceRNA regulatory mechanism and pathogenesis in HCC. mRNA and miRNA expression data and corresponding clinical characteristics of HCC patients were downloaded from The Cancer Genome Atlas Data Portal. The different expression profiles of mRNA, lncRNA, and miRNA (referred to as DEmRNAs, DElncRNAs, and DEmiR-NAs, respectively) screened 374 HCC tumor tissues and 50 adjacent nontumor control tissues. The miRcode database was used to predict interactions between DElncRNAs and DEmiRNAs. The miRTarBase, miRDB, and TargetScan databases were used to retrieve miRNA-targeted mRNAs. The lncRNA-miRNA-mRNA ceRNA network was constructed based on matched DElncRNA-DEmiRNA and DEmiRNA-DEmRNA pairs. Functional enrichment analysis revealed the biological processes and pathways of DEmRNAs involved in the development of HCC. Key differentially expressed RNAs in the ceRNA network were further analyzed for their relationships with overall survival in HCC patients. A total of 1,982 mRNAs, 1,081 lncRNAs, and 126 miRNAs were identified as differentially expressed. The ceRNA network was constructed including 74 DElncRNAs, 35 DEmRNAs, and 16 DEmiRNAs. 13 DElncRNAs and 19 DEmRNAs were identified as prognosis-related biomarkers. Twenty-five Gene Ontology terms and 8 Kyoto Encyclopedia of Genes and Genomes pathways were found to be significantly enriched by DEmRNAs in the ceRNA network. Our results demonstrated tumor-specific mRNA, lncRNA, and miRNA expression patterns and enabled us to construct a ceRNA network that provided new insights into the molecular mechanisms of HCC. Key differentially expressed RNAs associated with total survival were also identified as promising biomarkers for survival prediction.

Identification and Characterization of the Physiological Gene Targets of the Essential Lytic Replicative Epstein-Barr Virus SM Protein.

UNLABELLED: Epstein-Barr virus (EBV) SM protein is an essential lytic cycle protein with multiple posttranscriptional mechanisms of action. SM binds RNA and increases accumulation of specific EBV transcripts. Previous studies using microarrays and PCR have shown that SM-null mutants fail to accumulate several lytic cycle mRNAs and proteins at wild-type levels. However, the complete effect of SM on the EBV transcriptome has been incompletely characterized. Here we precisely identify the effects of SM on all EBV transcripts by high-throughput RNA sequencing, quantitative PCR (qPCR), and Northern blotting. The effect of SM on EBV mRNAs was highly skewed and was most evident on 13 late genes, demonstrating why SM is essential for infectious EBV production. EBV DNA replication was also partially impaired in SM mutants, suggesting additional roles for SM in EBV DNA replication. While it has been suggested that SM specificity is based on recognition of either RNA sequence motifs or other sequence properties, no such unifying property of SM-responsive targets was discernible. The binding affinity of mRNAs for SM also did not correlate with SM responsiveness. These data suggest that while target RNA binding by SM may be required for its effect, specific activation by SM is due to differences in inherent properties of individual transcripts. We therefore propose a new model for the mechanism of action and specificity of SM and its homologs in other herpesviruses: that they bind many RNAs but only enhance accumulation of those that are intrinsically unstable and poorly expressed. IMPORTANCE: This study examines the mechanism of action of EBV SM protein, which is essential for EBV replication and infectious virus production. Since SM protein is not similar to any cellular protein and has homologs in all other human herpesviruses, it has potential importance as a therapeutic target. Here we establish which EBV RNAs are most highly upregulated by SM, allowing us to understand why it is essential for EBV replication. By comparing and characterizing these RNA transcripts, we conclude that the mechanism of specific activity is unlikely to be based simply on preferential recognition of a target motif. Rather, SM binding to its target RNA may be necessary but not sufficient for enhancing accumulation of the RNA. Preferential effects of SM on its most responsive RNA targets may depend on other inherent characteristics of these specific mRNAs that require SM for efficient expression, such as RNA stability.

miR-124 targets GATA6 to suppress cholangiocarcinoma cell invasion and metastasis.

BACKGROUND: Our previous study showed that GATA6 plays important roles in cholangiocarcinoma (CCA) cell invasion and metastasis. However, the regulation mechanism of GATA6 in CCA is not clear. In this study, we studied the potential function of miR-124 in CCA and the mechanism of GATA6 regulation. METHODS: The expression levels of miR-124 and GATA6 in cancerous tissues from 57 CCA patients was detected by RT-PCR and IHC. The impact of miR-124 on GATA6 expression in CCA cells was evaluated using cell transfection, xenotransplantation into nude mice and a luciferase reporter assay. RESULTS: miR-124 was decreased in 57 cancerous tissue samples compared with 38 matched paracancerous samples. The miR-124 level was inversely associated with lymph node involvement and distant metastasis. miR-124 significantly inhibited invasion and migration of CCA cells in vitro. Furthermore, miR-124 inhibited CCA cell metastasis in nude mice. miR-124 inhibited the luciferase activity of reporter genes containing the wild-type GATA6 3'-UTR, which was abrogated by mutation of the binding site. The protein levels of GATA6 were negatively regulated by miR-124. miR-124 expression was inversely associated with GATA6 in 57 cancerous samples. The miR-124-induced suppression of CCA invasion was abrogated by remedial expression of GATA6. GATA6 expression was decreased by miR-124 overexpression in liver masses from nude mice. CONCLUSIONS: Our data suggested that miR-124 decreases GATA6 expression by targeting its 3'-UTR, which in turn inhibits CCA invasion and metastasis.

The development and validation of Huaxi emotional-distress index (HEI): A Chinese questionnaire for screening depression and anxiety in non-psychiatric clinical settings.

BACKGROUND: Depression and anxiety among general hospital patients are common and under-recognized in China. This study aimed toward developing a short questionnaire for screening depression and anxiety in non-psychiatric clinical settings, and to test its reliability and validity. METHODS: The item pool which included 35 questions about emotional distress was drafted through a comprehensive literature review. An expert panel review and the first clinical test with 288 general hospital patients were conducted for the primary item selection. The second clinical test was performed to select the final item in 637 non-psychiatric patients. The reliability and validity of the final questionnaire were tested in 763 non-psychiatric patients, in which 211 subjects were interviewed by psychiatrists using Mini International Neuropsychiatric Interview (MINI). Multiple data analysis methods including principal components analysis (PCA), item response theory (IRT), and receiver operating characteristic (ROC) curve were used to select items and validate the final questionnaire. RESULTS: The series selection of items resulted in a 9-item questionnaire, namely Huaxi Emotional-distress Index (HEI). The Cronbach's α coefficient of HEI was 0.90. The PCA results showed a unidimensional construct. The area under the ROC curve (AUC) was 0.88 when compared with MINI interview. Using the optimal cut-off score of HEI (≥11), the sensitivity and specificity were 0.880 and 0.766, respectively. CONCLUSIONS: The HEI is considered as a reliable and valid instrument for screening depression and anxiety, which may have substantial clinical value to detect patients' emotional disturbances especially in the busy non-psychiatric clinical settings in China.

Identification of the physiological gene targets of the essential lytic replicative Kaposi's sarcoma-associated herpesvirus ORF57 protein.

UNLABELLED: The Kaposi's sarcoma-associated herpesvirus (KSHV) ORF57 gene product is essential for lytic KSHV replication and virion production. Recombinant ORF57-null mutants fail to accumulate several lytic cycle mRNAs at wild-type levels, leading to decreased production of lytic proteins necessary for efficient replication. Several mechanisms by which ORF57 may enhance expression of lytic KSHV mRNAs have been proposed, including mRNA stabilization, mRNA nuclear export, increased polyadenylation, and transcriptional activation. ORF57 activity is also gene specific, with some genes being highly dependent on ORF57, whereas others are relatively independent. Most experiments have utilized transfection models for ORF57 and have not systematically examined the gene specificity and potential mechanisms of action of ORF57 in the context of KSHV-infected cells. In this study, the KSHV genes that are most highly upregulated by ORF57 during KSHV lytic replication were identified by a combination of high-throughput deep RNA sequencing, quantitative PCR, Northern blotting, and rapid amplification of cDNA ends methods. Comparison of gene expression from a ΔORF57 KSHV recombinant, a rescued ΔORF57 KSHV recombinant, and wild-type KSHV revealed that two clusters of lytic genes are most highly dependent on ORF57 for efficient expression. Despite contiguous location in the genome and shared polyadenylation of several of the ORF57-dependent genes, ORF57 regulation was promoter and polyadenylation signal independent, suggesting that the mRNAs are stabilized by ORF57. The eight genes identified to critically require ORF57 belong to both early and late lytic temporal classes, and seven are involved in DNA replication, virion assembly, or viral infectivity, explaining the essential role of ORF57 in infectious KSHV production. IMPORTANCE: Kaposi's sarcoma-associated herpesvirus (KSHV) is a human herpesvirus involved in the causation of several human cancers. The KSHV ORF57 protein is required for KSHV to replicate and produce infectious virus. We have identified several KSHV genes whose expression is highly dependent on ORF57 and shown that ORF57 increases expression of these genes specifically. These genes code for proteins that are required for the virus to replicate its DNA and to infect other cells. Identifying the targets and mechanism of action of ORF57 provides further approaches to discover antiviral therapy.

CTCF and Rad21 act as host cell restriction factors for Kaposi's sarcoma-associated herpesvirus (KSHV) lytic replication by modulating viral gene transcription.

Kaposi's sarcoma-associated herpesvirus (KSHV) is a human herpesvirus that causes Kaposi's sarcoma and is associated with the development of lymphoproliferative diseases. KSHV reactivation from latency and virion production is dependent on efficient transcription of over eighty lytic cycle genes and viral DNA replication. CTCF and cohesin, cellular proteins that cooperatively regulate gene expression and mediate long-range DNA interactions, have been shown to bind at specific sites in herpesvirus genomes. CTCF and cohesin regulate KSHV gene expression during latency and may also control lytic reactivation, although their role in lytic gene expression remains incompletely characterized. Here, we analyze the dynamic changes in CTCF and cohesin binding that occur during the process of KSHV viral reactivation and virion production by high resolution chromatin immunoprecipitation and deep sequencing (ChIP-Seq) and show that both proteins dissociate from viral genomes in kinetically and spatially distinct patterns. By utilizing siRNAs to specifically deplete CTCF and Rad21, a cohesin component, we demonstrate that both proteins are potent restriction factors for KSHV replication, with cohesin knockdown leading to hundred-fold increases in viral yield. High-throughput RNA sequencing was used to characterize the transcriptional effects of CTCF and cohesin depletion, and demonstrated that both proteins have complex and global effects on KSHV lytic transcription. Specifically, both proteins act as positive factors for viral transcription initially but subsequently inhibit KSHV lytic transcription, such that their net effect is to limit KSHV RNA accumulation. Cohesin is a more potent inhibitor of KSHV transcription than CTCF but both proteins are also required for efficient transcription of a subset of KSHV genes. These data reveal novel effects of CTCF and cohesin on transcription from a relatively small genome that resemble their effects on the cellular genome by acting as gene-specific activators of some promoters, but differ in acting as global negative regulators of transcription.

A single nucleotide polymorphism in the Epstein-Barr virus genome is strongly associated with a high risk of nasopharyngeal carcinoma.

BACKGROUND: Epstein-Barr virus (EBV) commonly infects the general population and has been associated with nasopharyngeal carcinoma (NPC), which has a high incidence in certain regions. This study aimed to address how EBV variations contribute to the risk of NPC. METHODS: Using logistic regression analysis and based on the sequence variations at EBV-encoded RPMS1, a multi-stage association study was conducted to identify EBV variations associated with NPC risk. A protein degradation assay was performed to characterize the functional relevance of the RPMS1 variations. RESULTS: Based on EBV-encoded RPMS1 variations, a single nucleotide polymorphism (SNP) in the EBV genome (locus 155391: G>A, named G155391A) was associated with NPC in 157 cases and 319 healthy controls from an NPC endemic region in South China [P < 0.001, odds ratio (OR) = 4.47, 95% confidence interval (CI) 2.71-7.37]. The results were further validated in three independent cohorts from the NPC endemic region (P < 0.001, OR = 5.20, 95% CI 3.18-8.50 in 168 cases vs. 241 controls, and P < 0.001, OR = 5.27, 95% CI 4.06-6.85 in 726 cases vs. 880 controls) and a non-endemic region (P < 0.001, OR = 7.52, 95% CI 3.69-15.32 in 58 cases vs. 612 controls). The combined analysis in 1109 cases and 2052 controls revealed that the SNP G155391A was strongly associated with NPC (P(combined) < 0.001, OR = 5.27, 95% CI 4.31-6.44). Moreover, the frequency of the SNP G155391A was associated with NPC incidence but was not associated with the incidences of other EBV-related malignancies. Furthermore, the protein degradation assay showed that this SNP decreased the degradation of the oncogenic RPMS1 protein. CONCLUSIONS: Our study identified an EBV variation specifically and significantly associated with a high risk of NPC. These findings provide insights into the pathogenesis of NPC and strategies for prevention.

[Effect of human concentration nucleoside transporters 1 and multi-drug resistance protein 4 gene polymorphism on response of chronic hepatitis B to nucleoside analogues treatment].

OBJECTIVE: To investigate the effect of human concentration nucleoside transporters 1 (hCNT1/ SLC28A1) and multi-drug resistance protein 4 (MRP4/ABCC4) gene polymorphism on the response of chronic hepatitis B patients to nucleoside analogues treatment. METHODS: There were 136 patients of chronic hepatitis B treated with entecavir (68) or telbivudine (68). The allele and gene frequency distributing of the four loci of hCNT1/SLC28A1 and MRP4/ABCC4 as well as the polymorphisms were detected in all patients by multiplex snapshot single base extension method. Based on the treatment response, the patients were divided into primary partial response (PPR) group and complete viral response (CVR) group, hCNTI/SLC28A1 and MRP4/ABCC4 gene polymorphism between these two groups were analyzed. RESULTS: The rates of PPR and CVR were 56. 6%00 (77 136) and 43. 4% (59/136) respectively. There was no statistical difference in baseline HBV DNA value, hepatitis B virus genotype and HBeAg status between PPR and CVR groups (P=0.148, P= 0. 622,P=0. 071) . The distribution of allelotype rs2290272 C/T and rs11568658 G/G in PPR group were higher than those in CVR group (P=0.043. P=0.049). Haplotype of C/A/T/C and C/C/G/G in CVR group were higher than those in PPR group (P=0. 024,P=0. 005). CONCLUSION: The single nucleotide polymorphisms (SNPs) of two candidate genes, including rs2290272 C/T of hCNT1/SLC28A1 and rs11568658 G/G of MRP4/ABCC4, may weak the response of chronic hepatitis B to nucleoside analogues treatment, as well as haplotype of C/A/T/C and C/C/G/G may enhance the response.

Expression and clinical significance of interleukin-6 pathway in cholangiocarcinoma.

Background: Cholangiocarcinoma (CCA) is a typical inflammation-induced malignancy, and elevated serum interleukin-6 (IL-6) levels have been reported to be linked to the onset and progression of CCA. We aim to investigate the potential prognostic value of the IL-6 pathway for CCA. Methods: We detected the expressions of IL-6, IL-6R, glycoprotein (gp130), C-reactive protein (CRP), Janus kinase 2 (JAK2), and signal transducer and activator of transcription 3 (STAT3) in CCA tissue microarray using multiplex immunofluorescence. Furthermore, the clinical associations and prognostic values were assessed. Finally, single-cell transcriptome analysis was performed to evaluate the expression level of IL-6 pathway genes in CCA. Results: The results revealed that the expression of IL-6 was lower, while the expression of STAT3 was higher in tumor tissues compared to normal tissues. Especially in tumor microenvironment, the expression of IL-6 pathway genes was generally downregulated. Importantly, gp130 was strongly correlated with JAK2 in tumor tissues, while it was moderately correlated with JAK2 in normal tissue. Although none of the gene expressions were directly associated with overall survival and disease-free survival, our study found that IL-6, IL-6R, CRP, gp130, and JAK2 were inversely correlated with vascular invasion, which is a risk factor for poor prognosis in patients with CCA. Conclusion: The findings from this study suggest that the IL-6 signaling pathway may have a potential prognostic value for CCA. Further investigation is needed to understand the underlying molecular mechanisms of the IL-6 pathway in CCA.

Ars2 is overexpressed in human cholangiocarcinomas and its depletion increases PTEN and PDCD4 by decreasing microRNA-21.

Due to the lack of effective diagnostic tools, most patients with cholangiocarcinoma (CCA) have no chance of surgical resection. Ars2 is a protein that was reported to be important for microRNA (miR) biogenesis, and its depletion can reduce the levels of several miRs, including miR-21, which is overexpressed in CCAs. We hypothesized that Ars2 was also present in CCAs and could be an early diagnostic marker. In our experiments, Ars2, PTEN, PDCD4, and miR-21 were evaluated in 18 CCAs and paired normal tissues. ShArs2, miR-21 mimics, and Ars2 were transfected into CCA and bile duct epithelial cells either alone or together. Cell proliferation, tumorigenicity analysis and expression changes of Ars2, PTEN, PDCD4, and miR-21 were evaluated. We found that both Ars2 and miR-21 were overexpressed, with 95% sensitivity and 100% specificity, and an ROC of 0.995 in distinguishing between CCAs and paired normal tissues by qRT-PCR. PTEN and PDCD4 were reversed in immunohistochemistry, but no difference was observed using qRT-PCR. The knockdown of Ars2 in CCA cells decreased the level of miR-21, inhibited cell proliferation and prevented tumor formation in nude mice. Ars2 knockdown also led to an increase in both PTEN and PDCD4 protein levels. Both proteins decreased when the miR-21 mimic was con-transfected. However, the overexpression of Ars2 alone could not get the opposite results. Based on our data, we conclude that Ars2 is overexpressed in human CCA and may be a diagnostic marker. Ars2 depletion increases PTEN and PDCD4 protein levels via the reduction of miR-21.

Binding of cellular export factor REF/Aly by Kaposi's sarcoma-associated herpesvirus (KSHV) ORF57 protein is not required for efficient KSHV lytic replication.

Kaposi's sarcoma-associated herpesvirus (KSHV) ORF57 protein is expressed early during lytic KSHV replication, enhances expression of many KSHV genes, and is essential for virus production. ORF57 is a member of a family of proteins conserved among all human and many animal herpesviruses that are multifunctional regulators of gene expression and act posttranscriptionally to increase accumulation of their target mRNAs. The mechanism of ORF57 action is complex and may involve effects on mRNA transcription, stability, and export. ORF57 directly binds to REF/Aly, a cellular RNA-binding protein component of the TREX complex that mediates RNA transcription and export. We analyzed the effects of an ORF57 mutation known to abrogate REF/Aly binding and demonstrate that the REF-binding mutant is impaired in activation of viral mRNAs and noncoding RNAs confined to the nucleus. Although the inability to bind REF leads to decreased ORF57 activity in enhancing gene expression, there is no demonstrable effect on nuclear export of viral mRNA or the ability of ORF57 to support KSHV replication and virus production. These data indicate that REF/Aly-ORF57 interaction is not essential for KSHV lytic replication but may contribute to target RNA stability independent of effects on RNA export, suggesting a novel role for REF/Aly in viral RNA metabolism.

Colonic involvement in disseminated histoplasmosis of an immunocompetent adult: case report and literature review.

BACKGROUND: Histoplasmosis is a common opportunistic fungal infection that is observed almost exclusively in immunodeficient patients, especially those with AIDS. Immunocompetent individuals that suffer from histoplasmosis are rarely reported, especially those with disseminated lesions, such as disseminated histoplasmosis. The observation of disseminated histoplasmosis with prominent gastrointestinal involvement, no respiratory symptoms (which is presumed to be the portal of infection), gastrointestinal pathological changes, and minor digestive system disorders make this case study exceedingly rare. CASE PRESENTATION: We report the case of a 33-year-old immunocompetent male who presented with fever and weight loss. Based on investigations, the patient showed pancytopenia, hepatosplenomegaly, bone marrow involvement and marked colonic involvement. Finally, disseminated histoplasmosis was diagnosed and confirmed by stained smears of fine needle aspirates and biopsy from lesions in the bone marrow and colon. The patient showed appreciable regression of lesions following prompt treatment with amphotericin B deoxycholate, and was treated thereafter with oral itraconazole following discharge from hospital. CONCLUSION: Disseminated histoplasmosis could be underestimated in immunocompetent patients. A high degree of clinical suspicion is essential in both immunocompromised and immunocompetent patients, regardless of pulmonary symptoms, and whether in endemic or non-endemic areas. Early and accurate diagnosis is extremely important for the appropriate treatment of infection and to improve disease outcome.

Depletion of HIV reservoir by activation of ISR signaling in resting CD4+T cells.

HIV reservoirs are extremely stable and pose a tremendous challenge to clear HIV infection. Here, we demonstrate that activation of ISR/ATF4 signaling reverses HIV latency, which also selectively eliminates HIV+ cells in primary CD4+T cell model of latency without effect on HIV-negative CD4+T cells. The reduction of HIV+ cells is associated with apoptosis enhancement, but surprisingly is largely seen in HIV-infected cells in which gag-pol RNA transcripts are detected in HIV RNA-induced ATF4/IFIT signaling. In resting CD4+ (rCD4+) T cells isolated from people living with HIV on antiretroviral therapy, induction of ISR/ATF4 signaling reduced HIV reservoirs by depletion of replication-competent HIV without global reduction in the rCD4+ T cell population. These findings suggest that compromised ISR/ATF4 signaling maintains stable and quiescent HIV reservoirs whereas activation of ISR/ATF4 signaling results in the disruption of latent HIV and clearance of persistently infected CD4+T cells.