Toll-like receptor 4 gene polymorphism influences dendritic cell in vitro function and clinical outcomes in vaccinated melanoma patients.

Toll-like receptor 4 (TLR4) is expressed on dendritic cells (DCs), sensing environmental danger molecules that induce their activation and maturation. Recently, we reported a method for the production of therapeutic DCs against melanoma, called tumor antigen-presenting cells (TAPCells), using a heat-shocked allogeneic melanoma cell lysate (TRIMEL) as an activation factor and antigen provider. Since TRIMEL contains endogenous TLR4 ligands, we evaluated the role of TLR4 in TAPCells differentiation by antibody neutralization and the association of a Tlr4 polymorphism (896A/G) (Asp299Gly), determined by PCR-RFLP, with the in vitro activation capacity and the clinical outcome of TAPCells-vaccinated patients. Antibody blocking of monocyte TLR4 inhibited surface expression, determined by flow cytometry, of the major histocompatibility complex class I, CCR7, CD80, CD83 and CD86 on TAPCells, reduced interleukin (IL)-6 and tumor necrosis factor -α gene expression evaluated by qRT-PCR, and also inhibited the TAPCells-mediated interferon-γ (IFN-γ) secretion of melanoma-specific CD8(+) T cells determined by ELISpot (p < 0.01). Moreover, CD8(+) T-cell activation capacity was significantly reduced in TAPCells bearing the TLR4 Asp299Gly receptor (p < 0.05). Finally, TAPCells-vaccinated stage-IV melanoma patients bearing the Tlr4 896G allele showed a shortened post-therapy median survival rate compared with those carrying the Tlr4 896A allele (p < 0.05; log-rank test). Our results indicate that TLR4 is a key receptor for the tumor lysate-mediated in vitro generation of clinically efficient antigen-presenting cells. Further analysis of patients included in different vaccine protocols is necessary for definitively establishing a role for TLR4 polymorphism in clinical responses.

Fam83F induces p53 stabilisation and promotes its activity.

p53 is one of the most important tumour suppressor proteins currently known. It is activated in response to DNA damage and this activation leads to proliferation arrest and cell death. The abundance and activity of p53 are tightly controlled and reductions in p53's activity can contribute to the development of cancer. Here, we show that Fam83F increases p53 protein levels by protein stabilisation. Fam83F interacts with p53 and decreases its ubiquitination and degradation. Fam83F is induced in response to DNA damage and its overexpression also increases p53 activity in cell culture experiments and in zebrafish embryos. Downregulation of Fam83F decreases transcription of p53 target genes in response to DNA damage and increases cell proliferation, identifying Fam83F as an important regulator of the DNA damage response. Overexpression of Fam83F also enhances migration of cells harbouring mutant p53 demonstrating that it can also activate mutant forms of p53.

Prolonged survival of dendritic cell-vaccinated melanoma patients correlates with tumor-specific delayed type IV hypersensitivity response and reduction of tumor growth factor beta-expressing T cells.

PURPOSE: The aim of this work was to assess immunologic response, disease progression, and post-treatment survival of melanoma patients vaccinated with autologous dendritic cells (DCs) pulsed with a novel allogeneic cell lysate (TRIMEL) derived from three melanoma cell lines. PATIENTS AND METHODS: Forty-three stage IV and seven stage III patients were vaccinated four times with TRIMEL/DC vaccine. Specific delayed type IV hypersensitivity (DTH) reaction, ex vivo cytokine production, and regulatory T-cell populations were determined. Overall survival and disease progression rates were analyzed using Kaplan-Meier curves and compared with historical records. RESULTS: The overall survival for stage IV patients was 15 months. More than 60% of patients showed DTH-positive reaction against the TRIMEL. Stage IV/DTH-positive patients displayed a median survival of 33 months compared with 11 months observed for DTH-negative patients (P = .0014). All stage III treated patients were DTH positive and remained alive and tumor free for a median follow-up period of 48 months (range, 33 to 64 months). DTH-positive patients showed a marked reduction in the proportion of CD4+ transforming growth factor (TGF) beta+ regulatory T cells compared to DTH-negative patients (1.54% v 5.78%; P < .0001). CONCLUSION: Our findings strongly suggest that TRIMEL-pulsed DCs provide a standardized and widely applicable source of melanoma antigens, very effective in evoking antimelanoma immune response. To our knowledge, this is the first report describing a correlation between vaccine-induced reduction of CD4+TGFbeta+ regulatory T cells and in vivo antimelanoma immune response associated to improved patient survival and disease stability.

Estudio comparativo de anestesia peridural balanceada bupivacaina al 0.0625 por ciento más fentanil vs. lidocaina al 1 por ciento en analgesia obstétrica / Comparative study of anethesia peridural space bupivacaine at 0.0625 per cent plus fentanyl vs. lidocaine at 1 per cent in obstetrics

Se realizó un estudio para comparar los resultados de la calidad y eficacia de la analgesia entre la Bupivacaína al 0.0625 por ciento más Fentanil Vs. Lidocaína al 1 por ciento en el espacio peridural de pacientes obstétricas en trabajo de parto. Se estudiaron 20 gestantes, ASA I, con edades comprendidas entre 15 y 30 en franco trabajo de parto, primigestas, nulíparas, en presentación cefálica de vértice, dilatación de 5 a 6 cms, en II plano, sin patología fetal ni criterios de exclusión para analgesia conductiva. Fueron distribuidas aleatoriamente en dos grupos: Grupo A Lidocaína al 1 por ciento (100 mg) en la primera y en la segunda fase; Grupo B Bupivacaína al 0.0625 por ciento (3.125 mg) más Fentanil (100 µg) en la primera fase, en la segunda fase Bupivacaína al 0.0625 por ciento (3.125 mg). El tiempo de inicio de la analgesia fue en el grupo A 6.1 min. (0.7) y en el B 7.5 min. (1.7). La calidad de la analgesia fue mejor en el grupo B. La duración del parto fue en el grupo A 38.3 min. (13) y en el B 44.5 min. (19.6). La duración de la analgesia fue de 47.1 min. (13.4) en el grupo A y 105.5 min (11,1) en el B. Ninguno de estos parámetros fue significativo (p<0.01). Para ambos grupós no se apreciaron variaciones hemodinámicas ni efectos colaterales de las drogas administradas en la madre ni en el feto. Se concluye que la combinación de Bupivacaína a bajas concentraciones más Fentanil es idónea para garantizar una analgesia eficaz, de buena calidad, prolongada, sin reacciones adversas