were then incubated in Apoptosis/Necro- sis Detection Kit buffer containing 1% v/ v 7-AAD and Annexin V-Cy3 (Enzo LifeSciences, Farmingdale, NY), and sub- jected to flow cytometry. Treatment with LsV or recLiD1 caused HFF-1 cell death after 48 hours, primarily due to apoptosis, which was not inhibited by Ki16425 (Figure 2a). The lack of inhibition was expected, as treatment with LPA did not cause cell death. Control LPC did not injure cells either (data not shown). As LPA can act as a cell survival or apoptotic factor, dependent upon the cell type (Ye et al., 2002), we performed the same procedures using human umbilical vein endothelial cells, which yielded similar results (Figure 2b). Thus, we did not find that LPA parti- cipates in apoptosis induced by LsV or recLiD1 in fibroblast and endothelial cells in vitro. These cells are known sites of Loxosceles venom interaction. Our results support the idea that PLD initiates the effects of Loxosceles venom through stimulation of acute inflamma- tory responses. In conclusion, LPA receptors are in- volved in the release of proinflammatory cytokines/chemokines provoked by LsV and recLiD1. The present work contri- butes to the open discussion regarding the participation of LPA in the patho- physiology of cutaneous loxoscelism and paves the way for investigation of new therapeutic strategies. CONFLICT OF INTEREST The authors state no conflict of interest. ACKNOWLEDGMENTS This work was supported by CNPq, CAPES, and FAPEMIG. We thank IEF/MG for the permission for spider collection. This study was developed in Belo Horizonte, Minas Gerais, Brazil. Carolina C.R. Horta 1 , Ba ´rbara B.R. Oliveira-Mendes 1 , Anderson O. do Carmo 1 , Fla ´via F. Siqueira 1 , Tatiana M. Barroca 1 , Samyra M. dos Santos Nassif Lacerda 2 , Paulo H. de Almeida Campos Jr 2 , Luiz R. de Franc ¸a 2 , Rodrigo L. 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Blood 93:2984–90 Mutations in ERBB4 May Have a Minor Role in Melanoma Pathogenesis Journal of Investigative Dermatology (2013) 133, 1685–1687; doi:10.1038/jid.2013.27; published online 21 February 2013 TO THE EDITOR In the recent past, an increasing amount of evidence has indicated that several alterations to the complex molecular machinery that provides checks and balances in normal melanocytes may be involved in the pathogenesis of mela- noma (Palmieri et al., 2009; Tsao et al., 2012). The different molecular pathways associated with melanomagenesis seem to correspond to specific subsets of melanoma patients, with distinguished biological and clinical behavior of the disease. In the era, just begun, of innovative targeted therapies for the treatment of melanoma (Ascierto et al., 2012; Flaherty et al., 2012), identi- fication of such different subsets of melanoma patients is becoming mandatory. Accepted article preview online 22 January 2013 A Manca et al. ERBB4 Mutations and Melanoma Pathogenesis www.jidonline.org 1685