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Purpose Crizotinib, a mesenchymal-epithelial transition/anaplastic lymphoma kinase/c-ros oncogene 1 (ROS1) inhibitor, has recently been approved by the US Food and Drug Administration for the treatment of patients with advanced ROS1-positive non–small-cell lung cancer (NSCLC). Therefore, interest in ROS1 testing is growing. ROS1 gene fusions affect approximately 0.5% to 2% of unselected NSCLCs. Limited data are available on the prevalence and distribution of ROS1 fusions in patients with advanced-stage NSCLC. Material and Methods A series of 727 lung adenocarcinomas from patients with stage IV disease, negative for epidermal growth factor receptor and anaplastic lymphoma kinase alterations, were tested for ROS1 fusions by fluorescent in situ hybridization analysis, with confirmation by immunohistochemistry. Results were correlated with clinicopathologic parameters and compared with data from the literature. Results ROS1 fusions were detected in 29 patients (4%), including 27 of 266 females (10.2%) and two of 461 males (0.4%; P = 1.2E-10). The mean age of patients with ROS1-positive disease was lower than that of patients with ROS1-negative disease (49.21 v 62.96 years, respectively; P = 1.1E-10). Eleven of 583 smokers (1.9%) and 18 of 144 nonsmokers (12.5%) showed ROS1 rearrangement ( P = 4.05E-7). By logistic regression analysis, ROS1 fusions were independently associated with female sex, younger age at diagnosis, and absence of smoking history, (odds ratios, 12.4, 7.9, and 3.6, respectively). These data, integrated with those reported in the literature, indicate that the prevalence of ROS1 fusions in females and in nonsmokers was higher in patients with advanced disease than in patients with operable disease (11.2% v 3.1%, P < .001; 11.6% v 2.8%, P < .001, respectively). The mean age at diagnosis was significantly lower in patients with advanced disease (49.8 years) than in patients with operable disease (55.6 years; P < .001). Conclusion Our data indicate that ROS1 fusions in patients with advanced-stage lung adenocarcinoma are more frequent in females, particularly if young and nonsmokers. A diagnostic algorithm for an accurate screening of ROS1 alterations was elaborated.

IL-7 is required for T cell differentiation and mature T cell homeostasis and promotes pro-B cell proliferation and survival. Tyrosine phosphorylation plays a central role in IL-7 signaling. We identified by two-dimensional electrophoresis followed by anti-phosphotyrosine immunoblotting and mass spectrometry sixteen tyrosine phosphorylated proteins from the IL-7-dependent cell line D1. IL-7 stimulation induced the phosphorylation of the proteins STI1, ATIC and hnRNPH, involved in pathways related to survival, proliferation and gene expression, respectively, and increased the phosphorylation of CrkL, a member of a family of adaptors including the highly homologous Crk isoforms CrkII and CrkI, important in multiple signaling pathways. We observed an increased phosphorylation of CrkL in murine pro-B cells and in murine and human T cells. In addition, IL-7 increased the association of CrkL with the transcription factor Stat5, essential for IL-7 pro-survival activity. The selective tyrosine kinase inhibitor Imatinib. counteracted the IL-7 pro-survival effect in D1 cells and decreased CrkL phosphorylation. These data suggested that CrkL could play a pro-survival role in IL-7-mediated signaling. We observed that pro-B cells also expressed, in addition to CrkL, the Crk isoforms CrkII and CrkI and therefore utilized pro-B cells conditionally deficient in all three to evaluate the role of these proteins. The observation that the IL-7 pro-survival effect was reduced in Crk/CrkL conditionally-deficient pro-B cells further pointed to a pro-survival role of these adaptors. To further evaluate the role of these proteins, gene expression studies were performed in Crk/CrkL conditionally-deficient pro-B cells. IL-7 decreased the transcription of the receptor LAIR1, which inhibits B cell proliferation, in a Crk/CrkL-dependent manner, suggesting that the Crk family of proteins may promote pro-B cell proliferation. Our data contribute to the understanding of IL-7 signaling and suggest the involvement of Crk family proteins in pathways promoting survival and proliferation.

BackgroundIn immunocompetent patients, acute toxoplasmosis is usually asymptomatic. We identified M1 macrophages in a case of symptomatic acute Toxoplasma gondii infection that resolved without treatment. M1 macrophages have been demonstrated in animal models of toxoplasmosis, but not in humans.Case presentationA 63-year-old woman presented with laterocervical and axillary bilateral lymphadenopathy. Her anamnesis defined an episode of high fever and prolonged asthenia 4 months previously, which suggested an infectious disease. Following laboratory, radiological, and pathological analyses, she was diagnosed with toxoplasmosis. Immunohistochemical analyses were performed on lymph node sections. More than 50% of the macrophages in the lymph node microgranulomas were M1 macrophages, defined by CD68+/p-Stat1+ staining, and the presence of T helper 1 lymphocytes indicated an immune response known to induce M1 macrophage polarization. Activated endothelial cells were found only in inflamed areas. No therapy was administered before or after diagnosis, and the lymphadenopathy resolved after a follow-up of 5 months.ConclusionsThis is the first report to demonstrate the presence of M1 macrophages in human toxoplasmosis. Our findings contribute to the understanding of the pathogenesis of toxoplasmosis, and encourage further studies on the role of macrophage polarization in human toxoplasmosis.