Impact of age on survival according to molecular tumor findings in children and adolescents with soft-tissue and bone sarcoma: The BIOSCA project.

BACKGROUND: Adolescents (15-19 years) with sarcoma are known to have significantly worse survival than children (0-14 years). One possible reason may be that the adolescent sarcomas exhibit specific biological characteristics resulting in differences in clinical presentation and treatment resistance behaviors. The BIOSCA project aims to further explore these age-related differences in survival accounting for molecular tumor characteristic in children and adolescents with sarcoma. METHODS: A retrospective national population-based observational study with documented somatic genetic analyses was conducted between 2011 and 2016 of all patients aged from 0 to 17 years with a diagnosis of sarcoma using the National Registry of Childhood Cancers Database. RESULTS: A total of 1637 children (0-9years: 40%), preadolescents (10-14years: 35%) and adolescents (15-17 years: 25%) with a diagnosis of bone (N = 845) or soft-tissue (N = 792) sarcoma were included. Adolescents had significantly worse outcome for undifferentiated small round cell sarcoma (USRCS), alveolar rhabdomyosarcoma (ARMS), and epithelioid sarcoma. Five-year overall survivals were worse among CIC-rearranged USRCS cases (47% [95%CI:21-69]) as compared to other USRCS, and PAX3::FOXO1 ARMS patients (44% [95%CI:32-55]) as compared to other ARMS. Adjusting for stage and genomic-profiling status, adolescents with USRCS were 1.6-fold more likely to die than children (P = 0.05), while the difference in survival between age of ARMS patients was weaken. Indeed, the prevalence of PAX3::FOXO1 increased significantly with age. CONCLUSION: Age was an independent prognostic factor of outcome only in patients with USRCS, while the association between age and survival of patients with ARMS could be partly explained by differences in prevalence of PAX3::FOXO1.

Extended pre-exposure prophylaxis with lopinavir-ritonavir versus lamivudine to prevent HIV-1 transmission through breastfeeding up to 50 weeks in infants in Africa (ANRS 12174): a randomised controlled trial.

BACKGROUND: Strategies to prevent postnatal mother-to-child transmission of HIV-1 in Africa, including infant prophylaxis, have never been assessed past 6 months of breastfeeding, despite breastfeeding being recommended up to 12 months after birth. We aimed to compare the efficacy and safety of infant prophylaxis with the two drug regimens (lamivudine or lopinavir-ritonavir) to prevent postnatal HIV-1 transmission up to 50 weeks of breastfeeding. METHODS: We did a randomised controlled trial in four sites in Burkina Faso, South Africa, Uganda, and Zambia in children born to HIV-1-infected mothers not eligible for antiretroviral therapy (CD4 count >350 cells per µL). An independent researcher electronically generated a randomisation schedule; we then used sequentially numbered envelopes to randomly assign (1:1) HIV-1-uninfected breastfed infants aged 7 days to either lopinavir-ritonavir or lamivudine (paediatric liquid formulations, twice a day) up to 1 week after complete cessation of breastfeeding or at the final visit at week 50. We stratified the randomisation by country and used permuted blocks of four and six. We used a study label on drug bottles to mask participants, study physicians, and assessors to the treatment allocation. The primary outcome was infant HIV-1 infection between age 7 days and 50 weeks, diagnosed every 3 months with HIV-1 DNA PCR, in the modified intention-to-treat population (all who attended at least one follow-up visit). This trial is registered with ClinicalTrials.gov, number NCT00640263. FINDINGS: Between Nov 16, 2009, and May 7, 2012, we enrolled and randomised 1273 infants and analysed 1236; 615 assigned to lopinavir-ritonavir or 621 assigned to lamivudine. 17 HIV-1 infections were diagnosed in the study period (eight in the lopinavir-ritonavir group and nine in the lamivudine group), resulting in cumulative HIV-1 infection of 1.4% (95% CI 0.4-2.5) and 1.5% (0.7-2.5), respectively. Infection rates did not differ between the two drug regimens (hazard ratio [HR] of lopinavir-ritonavir versus lamivudine of 0.90, 95% CI 0.35-2.34; p=0.83). Clinical and biological severe adverse events did not differ between groups; 251 (51%) infants had a grade 3-4 event in the lopinavir-ritonavir group compared with 246 (50%) in the lamivudine group. INTERPRETATION: Infant HIV-1 prophylaxis with lopinavir-ritonavir was not superior to lamivudine and both drugs led to very low rates of HIV-1 postnatal transmission for up to 50 weeks of breastfeeding. Infant pre-exposure prophylaxis should be extended until the end of HIV-1 exposure and mothers should be informed about the persistent risk of transmission throughout breastfeeding. FUNDING: INSERM/National Agency for Research on AIDS and Viral Hepatitis (including funds from the Total Foundation), European Developing Countries Clinical Trials Partnership, Research Council of Norway.

Production and characterization of mouse monoclonal antibodies reactive to Chikungunya envelope E2 glycoprotein.

Chikungunya fever is an arbovirosis of major impact in public health in Asia and Africa. Chikungunya (CHIK) virus is member of the genus Alphavirus and belongs to the Semliki Forest (SF) antigenic complex. We describe for the first time a panel of monoclonal antibodies (MAbs) reactive to CHIK envelope E2 glycoprotein. For the screening of E2-specific MAbs, we expressed a recombinant soluble CHIK E2 protein in Drosophila S2 cells. Analyzed by immunological methods, MAbs 3C3, 3E4, and 8A4 were selected on the basis of their reactivity. Their epitopes are located to the outer surface of CHIK virion. These MAbs have no cross reactivity with related members of SF antigenic complex with the notable exception of Igbo-Ora virus. Anti-CHIK E2 MAbs 3C3, 3E4, and 8A4 should be helpful for studying the biology of CHIK virus and pathogenesis of disease. The combination of 8A4 and 3E4 is suitable for developing a specific antigen-capture ELISA.

Impact of HIV-1 genetic diversity on plasma HIV-1 RNA Quantification: usefulness of the Agence Nationale de Recherches sur le SIDA second-generation long terminal repeat-based real-time reverse transcriptase polymerase chain reaction test.

The high genetic diversity of HIV-1 has a major impact on the quantification of plasma HIV-1 RNA, representing an increasingly difficult challenge. A total of 898 plasma specimens positive for HIV-1 RNA by commercial assays (Amplicor v1.5; Roche Diagnostic Systems, Alameda, CA or Versant v3.0; Bayer Diagnostics, Emeryville, CA) were tested using the Agence Nationale de Recherches sur le SIDA second-generation (G2) real-time reverse transcriptase polymerase chain reaction (RT-PCR) test: 518 samples containing HIV-1 of known subtype, including 88 from 2 subtype panels and 430 harboring B (n = 266) and non-B (n = 164) group M HIV-1 subtypes from patients followed up in 2002 through 2005 at Necker Hospital (Paris, France), and 380 samples from 10 different countries (Argentina, Cambodia, Cameroon, Central African Republic, France, Ivory Coast, Madagascar, Morocco, Thailand, and Zimbabwe). HIV-1 RNA values obtained by G2 real-time PCR were highly correlated with those obtained by the Amplicor v1.5 for B and non-B subtypes (R = 0.892 and 0.892, respectively) and for samples from diverse countries (R = 0.867 and 0.893 for real-time PCR vs. Amplicor v1.5 and real-time PCR vs. Versant v3.0, respectively). Approximately 30% of specimens harboring non-B subtypes were underquantified by at least -0.51 log10 in Amplicor v1.5 versus 5% underquantified in G2 real-time PCR. Discrepant results were also obtained with subtype B samples (14% underquantified by Amplicor v1.5 vs. 7% by G2 real-time PCR). Similar percentages were observed when comparing results obtained with the G2 real-time PCR assay with those obtained using the Versant assay. Addressing HIV-1 diversity, continual monitoring of HIV-1 RNA assays, together with molecular epidemiology studies, is required to improve the accuracy of all HIV RNA assays.

Increasing HIV type 1 polymorphic diversity but no resistance to antiretroviral drugs in untreated patients from Central African Republic: a 2005 study.

As the HIV-1 pandemic becomes increasingly complex and as new countries acceed to antiretroviral drugs, the molecular characterization of HIV-1 strains circulating has important implications for vaccine research and for the efficacy of treatments. To follow the evolution of HIV-1 diversity in African countries, we have carried out a molecular analysis of HIV-1 strains collected from 150 HIV-1-positive pregnant women recruited in Bangui, Central African Republic (CAR). We have sequenced reverse transcriptase (RT) and protease (PROT) genes to (1) characterize the subtypes and CRFs, (2) describe the polymorphism of RT and PROT, particularly at the positions of drug resistance mutations in subtype B, and (3) observe potential drug resistance mutations and evaluate the prevalence of isolates bearing such mutations in this untreated population. The results showed that there is a very high and increasing diversity of HIV-1 strains circulating in CAR; out of 117 samples sequenced, we have observed 45 CRF11_cpx, 22 subtypes A1, 13 subtypes G, 7 subtypes CRF01_AE, 3 subtypes B, 3 subtypes CRF02_AG, 2 of each subtype F2 and CRF09_cpx, and one of each subtype D, J, C, H, CRF06_cpx, CRF13_cpx, and CRF19_cpx; the remaining 13 strains showed discordant genomic results suggesting multiple recombinations leading to mosaic viruses. The polymorphism of RT and PROT was high compared to subtype B, particularly at some positions that have been involved in antiretroviral resistance in subtype B, but we could not observe any major resistance mutation in this sample of untreated patients. The prevalence of drug resistance mutations in this population was therefore clearly under the WHO 5% threshold.

Transport-deficient Pit2 phosphate transporters still modify cell surface oligomers structure in response to inorganic phosphate.

Pit2 is a member of the Pit family of inorganic phosphate transporters and serves as a gamma-retrovirus receptor in mammals. Pit2 contains two copies of the protein homology domain PD001131, which defines the Pit family. These domains are presumably in opposite topology with respect to the plasma membrane plane. We have mutated a serine residue conserved in almost all of the 192 known PD001131 sequences to alanine in each PD001131 domain of human Pit2. Expression in CHO cells showed that phosphate uptake was affected severely in mutants, whereas susceptibility to virus infection was conserved. We reported previously that the inorganic phosphate concentration affects both phosphate transport mediated by Pit2 and the conformation of cell-surface Pit2 oligomers. Cross-linking experiments in transport-incompetent Pit2 mutants indicated that structural changes induced by phosphate starvation or supply occur independently of the whole transport cycle. These results suggest that the structural reorganisation of cell-surface Pit2 occurred as a consequence of ion binding, a model consistent with the possible involvement of cell-surface Pit2 oligomers in inorganic phosphate sensing.