Purpose: In patients with a negative prostate biopsy and persistent suspicion of prostate cancer, additional analyses such as the PCA3 score, PHI and multiparametric magnetic resonance imaging have been proposed to reduce the number of unnecessary repeat biopsies. In this study we evaluate the diagnostic accuracy of PCA3, PHI, multiparametric magnetic resonance imaging and various combinations of these tests in the repeat biopsy setting. Materials and Methods: A total of 170 patients with an initial negative prostate biopsy and persistent suspicion of prostate cancer were enrolled in this prospective study. The patients underwent measurements of the total prostate specific antigen and free prostate specific antigen rate, along with PHI, PCA3 tests and multiparametric magnetic resonance imaging before standard repeat biopsy that was performed by urologists blinded to the multiparametric magnetic resonance imaging results. Multivariate logistic regression models with various combinations of PCA3, PHI and multiparametric magnetic resonance imaging were used to identify the predictors of prostate cancer with repeat biopsy, and the performance of these models was compared using ROC curves, AUC analysis and decision curve analysis. Results: In the ROC analysis the most significant contribution was provided by multiparametric magnetic resonance imaging (AUC 0.936), which was greater than the contribution of the PHIþPCA3 model (p <0.001). In the multivariate logistic regression analysis only multiparametric magnetic resonance imaging was a significant independent predictor of prostate cancer diagnosis with repeat biopsy (p <0.001). The results of the decision curve analysis confirmed that the most significant improvement in the net benefit was provided by multiparametric magnetic resonance imaging.

Epidemiological evidence from the current outbreak of Zika virus (ZIKV) and recent studies in animal models indicate a strong causal link between ZIKV and microcephaly. ZIKV infection induces cell-cycle arrest and apoptosis in proliferating neural progenitors. However, the mechanisms leading to these phenotypes are still largely obscure. In this report, we explored the possible similarities between transcriptional responses induced by ZIKV in human neural progenitors and those elicited by three different genetic mutations leading to severe forms of microcephaly in mice. We found that the strongest similarity between all these conditions is the activation of common P53 downstream genes. In agreement with these observations, we report that ZIKV infection increases total P53 levels and nuclear accumulation, as well as P53 Ser15 phosphorylation, correlated with genotoxic stress and apoptosis induction. Interestingly, increased P53 activation and apoptosis are induced not only in cells expressing high levels of viral antigens but also in cells showing low or undetectable levels of the same proteins. These results indicate that P53 activation is an early and specific event in ZIKV-infected cells, which could result from cell-autonomous and/or non-cell-autonomous mechanisms. Moreover, we highlight a small group of P53 effector proteins that could act as critical mediators, not only in ZIKV-induced microcephaly but also in many genetic microcephaly syndromes.

In phagocytes, GTPases of the Rac family control crucial antimicrobial functions. The RacGAP ArhGAP15 negatively modulates Rac activity in leukocytes, but its in vivo role in innate immunity remains largely unknown. Here we show that neutrophils and macrophages derived from mice lacking ArhGAP15 presented higher Rac activity but distinct phenotypes. In macrophages, the loss of ArhGAP15 induced increased cellular elongation and membrane protrusions but did not modify chemotactic responses. Conversely, the lack of ArhGAP15 in neutrophils affected critical Rac-dependent antimicrobial functions, specifically causing enhanced chemotactic responses, straighter directional migration, amplified reactive oxygen species production, increased phagocytosis, and improved bacterial killing. IntroductionRac proteins are members of the Rho family of GTPases and are key mediators of phagocyte functions, through their involvement in the control of migration to the site of infection, phagocytosis, and reactive oxygen species (ROS) production. 1 In neutrophils, Rac is needed for proper gradient sensing 2-4 and filamentous actin polymerization 2 during migration. On the other hand, in macrophages, Rac can alter cell morphology and mode of migration but is not essential for chemotaxis. 5 In phagocytosis, Rac plays an important role in neutrophils 6 and macrophages by localizing to the phagosomal membrane and controlling the closure of the phagocytic cup. 7 Rac also mediates phagocyte-mediated bacterial killing, through its ability to stimulate ROS production, 3,6,8 as Rac can directly bind to p67 phox , thereby inducing the activation of the nicotinamide adenine dinucleotide phosphate oxidase complex (NADPH). 9 Consistent with these roles, human patients carrying a dominant negative Rac mutation show defective neutrophil chemotaxis, reduced superoxide production, and increased susceptibility to infections. 10,11 Like all GTPases, Rac proteins can oscillate between two states: the guanosine diphosphate-bound inactive and guanosine triphosphatebound active state. The switch between these two conditions is regulated by guanine nucleotide exchange factors and GTPase-activating proteins (GAPs): whereas guanine nucleotide exchange factors promote the exchange of guanosine diphosphate for guanosine triphosphate thus causing Rac activation, GAPs turn off Rac activity by accelerating the hydrolysis of guanosine triphosphate. It is estimated that 0.5% of all predicted human genes encode putative GAPs, thereby suggesting that these proteins have widespread and important roles in GTPase regulation 12 ; however, how RacGAPs regulate phagocyte functions remains largely unknown.In phagocytes, the best characterized RacGAPs are Bcr and Abr, which have been found to have overlapping roles. In particular, these proteins negatively control most of the Rac-dependent functions in macrophages, 13 whereas, conversely, they only regulate specific activities in neutrophils. 14,15 Nonetheless, although the presence of other RacGAPs in neutrophils has been re...

Background: IgG 4-related disease (IgG 4-RD) is a fibroinflammatory condition marked by rapid clinical improvement after selective depletion of B lymphocytes with rituximab. This feature suggests that B cells might participate in fibrogenesis and wound healing. Objective: In the present work we aimed to demonstrate that B lymphocytes contribute directly to tissue fibrosis in patients with IgG 4-RD. Methods: Total circulating CD19 1 B lymphocytes, naive B cells, memory B cells, or plasmablasts from patients with IgG 4-RD were cultivated with human fibroblasts. Profibrotic soluble factors and collagen production in cocultures were assessed by using ELISAs and Luminex assays. RNA sequencing and quantitative RT-PCR were used to assess fibroblast activation in the presence of B cells, as well as induction of profibrotic pathways in B-cell subsets. Relevant profibrotic and inflammatory molecules were confirmed in vitro by using functional experiments and on IgG 4-RD tissue sections by using multicolor immunofluorescence studies. Results: B cells from patients with IgG 4-RD (1) produced the profibrotic molecule platelet-derived growth factor B and stimulated collagen production by fibroblasts; (2) expressed enzymes implicated in extracellular matrix remodeling, such as lysyl oxidase homolog 2; (3) produced the chemotactic factors CCL4, CCL5, and CCL11; and (4) induced production of these same chemokines by activated fibroblasts. Plasmablasts expressed sets of genes implicated in fibroblast activation and proliferation and therefore represent cells with intrinsic profibrotic properties. Conclusion: We have demonstrated that B cells contribute directly to tissue fibrosis in patients with IgG 4-RD. These unanticipated profibrotic properties of B lymphocytes, particularly plasmablasts, might be relevant for fibrogenesis in patients with other fibroinflammatory disorders and for woundhealing processes in physiologic conditions.