Gene-to-gene coordinated regulation of transcription and alternative splicing by 3D chromatin remodeling upon NF-κB activation.

The NF-κB protein p65/RelA plays a pivotal role in coordinating gene expression in response to diverse stimuli, including viral infections. At the chromatin level, p65/RelA regulates gene transcription and alternative splicing through promoter enrichment and genomic exon occupancy, respectively. The intricate ways in which p65/RelA simultaneously governs these functions across various genes remain to be fully elucidated. In this study, we employed the HTLV-1 Tax oncoprotein, a potent activator of NF-κB, to investigate its influence on the three-dimensional organization of the genome, a key factor in gene regulation. We discovered that Tax restructures the 3D genomic landscape, bringing together genes based on their regulation and splicing patterns. Notably, we found that the Tax-induced gene-gene contact between the two master genes NFKBIA and RELA is associated with their respective changes in gene expression and alternative splicing. Through dCas9-mediated approaches, we demonstrated that NFKBIA-RELA interaction is required for alternative splicing regulation and is caused by an intragenic enrichment of p65/RelA on RELA. Our findings shed light on new regulatory mechanisms upon HTLV-1 Tax and underscore the integral role of p65/RelA in coordinated regulation of NF-κB-responsive genes at both transcriptional and splicing levels in the context of the 3D genome.

The NF-κB pathway is essential for coordinating gene expression in response to various stimuli, including viral infections. Most studies have focused on the role of NF-κB in transcriptional regulation. In the present study, the impact of the potent NF-κB activator HTLV-1 Tax oncoprotein on the three-dimensional organization of the genome was investigated. Tax-mediated NF-κB activation was found to restructure the 3D genomic landscape in cells and to bring genes together in multigene complexes that are coordinately regulated either transcriptionally or through alternative splicing by NF-κB. Induced coordinate changes in transcription and alternative splicing included the two master genes of NF-κB pathway NFKBIA and RELA. The findings have significant implications for understanding cell fate determination and disease development associated with HTLV-1 infection, as well as chronic NF-κB activation in various human inflammatory diseases and cancer.

The Cascade of Care for Hepatitis C Treatment in Rwanda: A Retrospective Cohort Study of the 2017-2019 Mass Screening and Treatment Campaign.

Access to hepatitis C (HCV) testing and treatment is still limited globally. To address this, the Government of Rwanda launched a voluntary mass screening and treatment campaign in 2017. We studied the progression of patients through the cascade of HCV care during this campaign. We conducted a retrospective cohort study and included all patients screened at 46 hospitals between April 2017 and October 2019. We used hierarchical logistic regression to assess factors associated with HCV positivity, gaps in care, and treatment failure. A total of 860,801 people attended the mass screening during the study period. Some 5.7% tested positive for anti-HCV, and 2.9% were confirmed positive. Of those who were confirmed positive, 52% initiated treatment, and 72% of those initiated treatment, completed treatment and returned for assessment 12 weeks afterward. The cure rate was 88%. HCV positivity was associated with age, socio-economic status, sex, marital status, and HIV coinfection. Treatment failure was associated with cirrhosis, baseline viral load, and a family history of HCV. Our results suggest that future HCV screening and testing interventions in Rwanda and other similar settings should target high-risk groups. High dropout rates suggest that more effort should be put into patient follow-up to increase adherence to care.

Effect of human papilloma virus vaccination on sexual behaviours among adolescent women in Rwanda: a regression discontinuity study.

Increasing human papilloma virus (HPV) vaccination coverage is one of the key approaches to preventing cervical cancer globally. However, some argue that HPV vaccine recipients may engage in risky compensatory sexual behaviours because of perceived protection afforded by the vaccine. Therefore, we investigated the impact of a wide-scale HPV vaccination programme on sexual behaviours among adolescent women in Rwanda-the first African country to implement a national HPV vaccination. We identified a cohort of women who were eligible for the HPV vaccination and those who were not eligible from the most recent Rwanda Demographic and Health Survey. We used a quasi-experimental regression discontinuity design, exploiting the quasi-random change in HPV vaccination eligibility in 2011, to compare sexual behaviours among vaccinated and unvaccinated adolescent women. We studied the impact of the vaccination on reported sexual intercourse, average number of sexual partners and teenage pregnancy across the vaccination eligibility threshold. Our analysis included 3052 adolescent women (mean age: 18.6 years), of whom 58% were eligible for HPV vaccination. Nearly one in five adolescents reported having had sexual intercourse (18.5%). The average reported lifetime number of sexual partners was 1.41. The proportion of teenage pregnancy was 5.3%. We found no evidence that HPV vaccination was associated with any significant changes across the eligibility threshold in reported sexual behaviours we studied: no significant increase in the proportion of having sexual intercourse [odds ratio (OR): 0.80, 95% confidence interval (CI): 0.57-1.12; P = 0.19], in lifetime number of sexual partners (rate ratio 0.99, 95% CI: 0.83-1.17, P = 0.91) and in the proportion of teen pregnancies (OR 1.05, 95% CI: 0.50 to 2.20, P = 0.89) at the eligibility threshold. The Rwandan national HPV vaccination programme did not increase sexual behaviours among adolescent women, assuaging concerns of engaging in risky compensatory sexual behaviours some have feared.

Role of unsafe medical practices and sexual behaviours in the hepatitis B and C syndemic and HIV co-infection in Rwanda: a cross-sectional study.

OBJECTIVES: This study describes the burden of the hepatitis B, C and HIV co-infections and assesses associated risk factors. SETTING: This analysis used data from a viral hepatitis screening campaign conducted in six districts in Rwanda from April to May 2019. Ten health centres per district were selected according to population size and distance. PARTICIPANTS: The campaign collected information from 156 499 participants (51 496 males and 104 953 females) on sociodemographic, clinical and behavioural characteristics. People who were not Rwandan by nationality or under 15 years old were excluded. PRIMARY AND SECONDARY OUTCOMES: The outcomes of interest included chronic hepatitis C virus (HCV) infection, chronic hepatitis B virus (HBV) infection, HIV infection, co-infection HIV/HBV, co-infection HIV/HCV, co-infection HBV/HCV and co-infection HCV/HBV/HIV. Multivariable logistic regressions were used to assess factors associated with HBV, HCV and HIV, mono and co-infections. RESULTS: Of 156 499 individuals screened, 3465 (2.2%) were hepatitis B surface antigen positive and 83% (2872/3465) of them had detectable HBV desoxy-nucleic acid (HBV DNA). A total of 4382 (2.8%) individuals were positive for antibody-HCV (anti-HCV) and 3163 (72.2%) had detectable HCV ribo-nucleic acid (RNA). Overall, 36 (0.02%) had HBV/HCV co-infection, 153 (0.1%) HBV/HIV co-infection, 238 (0.15%) HCV/HIV co-infection and 3 (0.002%) had triple infection. Scarification or receiving an operation from traditional healer was associated with all infections. Healthcare risk factors-history of surgery or transfusion-were associated with higher likelihood of HIV infection with OR 1.42 (95% CI 1.21 to 1.66) and OR 1.48 (1.29 to 1.70), respectively, while history of physical traumatic assault was associated with a higher likelihood of HIV and HBV/HIV co-infections with OR 1.69 (95% CI 1.51 to 1.88) and OR 1.82 (1.08 to 3.05), respectively. CONCLUSIONS: Overall, mono-infections were common and there were differences in significant risk factors associated with various infections. These findings highlight the magnitude of co-infections and differences in underlying risk factors that are important for designing prevention and care programmes.

Intragenic recruitment of NF-κB drives splicing modifications upon activation by the oncogene Tax of HTLV-1.

Chronic NF-κB activation in inflammation and cancer has long been linked to persistent activation of NF-κB-responsive gene promoters. However, NF-κB factors also massively bind to gene bodies. Here, we demonstrate that recruitment of the NF-κB factor RELA to intragenic regions regulates alternative splicing upon NF-κB activation by the viral oncogene Tax of HTLV-1. Integrative analyses of RNA splicing and chromatin occupancy, combined with chromatin tethering assays, demonstrate that DNA-bound RELA interacts with and recruits the splicing regulator DDX17, in an NF-κB activation-dependent manner. This leads to alternative splicing of target exons due to the RNA helicase activity of DDX17. Similar results were obtained upon Tax-independent NF-κB activation, indicating that Tax likely exacerbates a physiological process where RELA provides splice target specificity. Collectively, our results demonstrate a physical and direct involvement of NF-κB in alternative splicing regulation, which significantly revisits our knowledge of HTLV-1 pathogenesis and other NF-κB-related diseases.

Risk factors for viral hepatitis C infection in Rwanda: results from a nationwide screening program.

BACKGROUND: The epidemiology and risk factors for hepatitis C virus (HCV) infection in Rwanda are not well known; however, this information is crucial to shaping the country's public health approach to hepatitis C control. METHODS: A HCV screening campaign was conducted in the general population in 24 districts previously identified to have a high HCV disease burden. At the time of sample collection, sociodemographic information and self-reported risk factors were collected. Bivariate and multivariate logistic regressions were conducted to assess risk factors independently associated with hepatitis C antibodies (HCVAb) seroprevalence. RESULTS: Out of a total of 326,263 individuals screened for HCVAb, 22,183 (6.8%) were positive. In multivariate analysis, risk factors identified as statistically associated with HCVAb Seroprevalence include history of traditional operation or scarification (OR = 1.09, 95% CI: 1.05-1.14), presence of viral hepatitis in the family (OR = 1.27, 95% CI: 1.15-1.40), widowed or separated/divorced (OR = 1.36, 95% CI: 1.26-1.47), Southern province (OR = 1.98, 95% CI: 1.88-2.08) and aged 65 years and older (OR = 4.86, 95% CI: 4.62-5.11). Ubudehe category 3 (OR = 0.97, 95% CI: 0.93-1.01) and participants using RAMA (Health insurances for employees of public and private sectors) insurance (OR = 0.76, 95% CI: 0.70-0.85) had lower odds of HCV seroprevalence. CONCLUSIONS: Our findings provide important information for Rwanda's strategy on prevention and case-finding. Future prevention interventions should aim to reduce transmission through targeted messaging around traditional healing practices and case-finding targeting individuals with a history of exposure or advanced age.

Malignant transformations in a patient with a mediastinal germ cell tumour: lack of efficacy of bone marrow transplantation after chemotherapy on tumour recurrence.

The report describes the case of a young male with a malignant teratoma which was followed by an acute megakaryoblastic leukaemia sharing similar chromosomal abnormalities. In leukemic cells, the authors have obtained cytogenetic evidence by fluorescent in situ hybridisation technique suggesting that this leukaemia arose directly from the germ cell tumour (GCT). The patient received allogenic bone marrow transplantation, which unfortunately, did not prevent the patient to relapse with an undifferentiated sarcoma containing rhabdomyosarcoma components, as well as reappearance of a residual teratoma with metastasis. The treatment strategy for malignant transformation of a GCT seems to be unpredictable and should be dictated by the malignant tissue counterpart. Except for acute leukaemia, unresectable or metastatic settings will generally require multi-modal therapy including chemotherapy, in addition to loco regional approaches. Additionally, long or even a life time follow-up is necessary in patients with poor prognostic characteristics.

Selective regulation of presynaptic calcium/calmodulin-dependent protein kinase II by psychotropic drugs.

BACKGROUND: Changes in neuroplasticity have been involved in the pathogenesis of psychiatric disorders as well as in psychotropic drug action. Calcium/calmodulin-dependent protein kinase II (CaM kinase II), an enzyme with a pivotal role in synaptic plasticity and cognitive functions, has been implicated in the action of anticonvulsants, benzodiazepines, and antidepressants, but little is known as to its role in the action of different drugs employed for treatment of psychiatric disorders. METHODS: We studied the function and expression of CaM kinase II following chronic treatment of rats with two antidepressants, fluvoxamine and desipramine, a typical antipsychotic drug, haloperidol, and the typical medication for manic-depressive disorder, lithium. RESULTS: Antidepressants significantly increased the kinase activity in presynaptic vesicles of frontal/prefrontal cortex. Haloperidol induced no change, whereas lithium significantly decreased the activity. Kinase activation by antidepressants was further demonstrated by increased phosphorylation of exogenously added recombinant synaptotagmin. Immunoreactivity of vesicular kinase (alpha-isoform) was significantly increased by reuptake blockers but not by the two other drugs. Kinetic analysis showed that limiting value of enzymatic velocity (Vmax) of the kinase for substrate was also increased by reuptake blockers and decreased by lithium; however, neither messenger ribonucleic acid nor protein expression level of the kinase was increased in frontal/prefrontal cortex homogenates of antidepressant-treated rats, suggesting the involvement of local synaptic mechanisms. CONCLUSIONS: These findings show that functional regulation of presynaptic CaM kinase II is selectively affected by different psychotropic drugs, and suggest local synaptic mechanisms for pharmacological regulation of the kinase.