Influence of HLA-DRB1 and HLA-DQB1 Alleles on IgG Antibody Response to the P. vivax MSP-1, MSP-3α and MSP-9 in Individuals from Brazilian Endemic Area

Background: the antibody response generated during malaria infections is of particular interest, since the production of specific IgG antibodies is required for acquisition of clinical immunity. However, variations in antibody responses could result from genetic polymorphism of the HLA class II genes. Given the increasing focus on the development of subunit vaccines, studies of the influence of class II alleles on the immune response in ethnically diverse populations is important, prior to the implementation of vaccine trials.Methods and Findings: in this study, we evaluated the influence of HLA-DRB1* and -DQB1* allelic groups on the naturally acquired humoral response from Brazilian Amazon individuals (n = 276) against P. vivax Merozoite Surface Protein-1 (MSP-1), MSP-3 alpha and MSP-9 recombinant proteins. Our results provide information concerning these three P. vivax antigens, relevant for their role as immunogenic surface proteins and vaccine candidates. Firstly, the studied population was heterogeneous presenting 13 HLA-DRB1* and 5 DQB1* allelic groups with a higher frequency of HLA-DRB1*04 and HLA-DQB1*03. the proteins studied were broadly immunogenic in a naturally exposed population with high frequency of IgG antibodies against PvMSP1-19 (86.7%), PvMSP-3 (77%) and PvMSP-9 (76%). Moreover, HLA-DRB1*04 and HLA-DQB1*03 alleles were associated with a higher frequency of IgG immune responses against five out of nine antigens tested, while HLA-DRB1* 01 was associated with a high frequency of non-responders to repetitive regions of PvMSP-9, and the DRB1*16 allelic group with the low frequency of responders to PvMSP3 full length recombinant protein.Conclusions: HLA-DRB1*04 alleles were associated with high frequency of antibody responses to five out of nine recombinant proteins tested in Rondonia State, Brazil. These features could increase the success rate of future clinical trials based on these vaccine candidates.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Yerkes National Primate Research Center BaseNational Center for Research Resources of the National Institutes of HealthNIHCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Inst Oswaldo Cruz, Lab Immunoparasitol, BR-20001 Rio de Janeiro, BrazilOswaldo Cruz Fdn Fiocruz, Ctr Technol Dev Hlth CDTS, Rio de Janeiro, BrazilInst Oswaldo Cruz, Lab Simulideos & Oncocercose, BR-20001 Rio de Janeiro, BrazilEmory Univ, Emory Vaccine Ctr, Atlanta, GA 30322 USAUniv Estado Rio de Janeiro, Histocompatibil & Cryopreservat Lab, Rio de Janeiro, BrazilUniversidade Federal de São Paulo, Ctr Terapia Celular & Mol CTCMol, Escola Paulista Med, São Paulo, BrazilEmory Univ, Sch Med, Div Infect Dis, Atlanta, GA USACDC Natl Ctr Infect Dis, Div Parasit Dis, Atlanta, GA USAUniversidade Federal de São Paulo, Ctr Terapia Celular & Mol CTCMol, Escola Paulista Med, São Paulo, BrazilFAPESP: 2009/15132-4Yerkes National Primate Research Center Base: RR00165NIH: RO1 AI0555994Web of Scienc

Abstract P6-12-15: Efficacy results of a phase 1/2 study of glucocorticoid receptor (GR) antagonist mifepristone (MIFE) in combination with eribulin in GR-positive triple-negative breast cancer (TNBC)

Abstract Background: GR is variably expressed in TNBC and high expression is associated with poor prognosis in estrogen receptor-negative (ER-) early stage breast cancer. Treatment with mifepristone (MIFE) potentiates the effectiveness of chemotherapy in GR+ TNBC xenografts. Enrollment is complete in this study of patients with GR+ TNBC treated at the recommended Phase 2 dose (RP2D) of MIFE in combination with eribulin. Objectives: To determine the safety, tolerability, pharmacokinetics (PK) and clinical activity of the MIFE plus eribulin combination in pts with GR+ TNBC at the RP2D. Methods: Eligibility: In Part 1 (dose finding), pts with solid tumors; in Part 2 (expansion phase), pts with TNBC (GR result required at time of screening in Part 1, but could be pending at time of screening in Part 2). Up to 5 prior chemotherapy regimens for advanced disease; ECOG PS 0-1; adequate end-organ function. Design: 3 + 3 dose escalation scheme. After a 7-day lead-in of oral daily MIFE alone, MIFE was continued daily and eribulin was given on days 1 and 8 of a 21-day cycle. GR+ was defined as &amp;gt;10% of tumor cells with any intensity of GR staining. Results: 16 pts with metastatic breast cancer were treated in Part 1, and 21 pts with TNBC were treated in Part 2. Median age was 54 (range 30-81). MTD/RP2D was MIFE 300 mg/day + eribulin 1.1 mg/m2. Safety: DLT in Part 1 was neutropenia. Neutropenia occurred in 23/36 total patients (2 Grade [G] 1, 10 G3, 11 G4); 2 instances included neutropenic fever. Recovery of WBC was brisk with growth factor support. Neuropathy was observed in 8 pts (5 G1, 1 G2, 2 G3). Other most common AEs (fatigue, hypokalemia, nausea, alopecia) were mainly G1 or G2; among these, G3/G4 events were limited to fatigue (4 G3), hypokalemia (3 G3 and 1 G4) and nausea (1 G3). There were 2 instances of G1 vaginal bleeding. There was no impact of MIFE on eribulin PK. Efficacy: There were 23 evaluable pts with TNBC across Parts 1 and 2 treated at the RP2D: 21 GR+, 2 GR status unknown; median of 3 prior chemotherapy regimens; 1 patient had received prior eribulin. Responses were: 3 PR, 8 SD, 11 PD and one too early to assess. Median PFS was 9 weeks. Conclusions: MIFE plus eribulin was well tolerated and appears to be an active treatment regimen. Five TNBC patients had a PFS longer than the upper 95% CI for PFS (i.e., &amp;gt;15 wks) reported by Aogi et al. for TNBC treated with eribulin (Annals of Oncology 2012?23:144148). Clinical trial information: NCT02014337. Citation Format: Han HS, Wilks S, Paplomata E, Modiano MR, Becerra C, Braiteh FS, Spira AI, Pluard TJ, Richards DA, Conzen SD, Baker G, Fishman RS, Marcantonio A, O'Shaughnessy J, Nanda R. Efficacy results of a phase 1/2 study of glucocorticoid receptor (GR) antagonist mifepristone (MIFE) in combination with eribulin in GR-positive triple-negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-15.</jats:p

Gene expression profiles of sporadic canine hemangiosarcoma are uniquely associated with breed.

The role an individual's genetic background plays on phenotype and biological behavior of sporadic tumors remains incompletely understood. We showed previously that lymphomas from Golden Retrievers harbor defined, recurrent chromosomal aberrations that occur less frequently in lymphomas from other dog breeds, suggesting spontaneous canine tumors provide suitable models to define how heritable traits influence cancer genotypes. Here, we report a complementary approach using gene expression profiling in a naturally occurring endothelial sarcoma of dogs (hemangiosarcoma). Naturally occurring hemangiosarcomas of Golden Retrievers clustered separately from those of non-Golden Retrievers, with contributions from transcription factors, survival factors, and from pro-inflammatory and angiogenic genes, and which were exclusively present in hemangiosarcoma and not in other tumors or normal cells (i.e., they were not due simply to variation in these genes among breeds). Vascular Endothelial Growth Factor Receptor 1 (VEGFR1) was among genes preferentially enriched within known pathways derived from gene set enrichment analysis when characterizing tumors from Golden Retrievers versus other breeds. Heightened VEGFR1 expression in these tumors also was apparent at the protein level and targeted inhibition of VEGFR1 increased proliferation of hemangiosarcoma cells derived from tumors of Golden Retrievers, but not from other breeds. Our results suggest heritable factors mold gene expression phenotypes, and consequently biological behavior in sporadic, naturally occurring tumors