Modulation of LPS-Induced Activation of Hepatic Map Kinases

Lipopolysaccharide (LPS) is a potent inflammagen that has been found to be primarily responsible for many symptoms caused by gram-negative bacterial infections. The LPS-initiated signal transduction pathways involve several terminal kinases, mainly p42/44 mitogen-activated protein kinase (MAPK), p38 MAPK and c-Jun N-terminal kinase (JNK), ultimately leading to increased expression of genes encoding such inflammatory cytokines as interleukin (IL )-1 �. IL-6 and tumor necrosis factors (TNF)-u. In this study, the effects of age on LPS-induced activation of MAPKs in the liver of rats were examined. Results show that the basal level of phosphorylated p42/44 MAPK was increased in postnatal day (P) 21 and P70 compared to P 1 animals treated with saline, and that LPS significantly increased the phosphorylation of p42/44 MAPK at P21 and P70. On the other hand, both basal and phosphorylated p38 MAPK did not show significant changes in P21 and P70 liver compared to PI. The effects of maternal exposure to LPS on the activation of MAPKs in P21 offspring liver were also examined. Results show that p42/44 MAPK activation was significantly decreased in the liver of pups born to LPS-treated dams as compared to those born to saline-treated dams following LPS stimulation. However, p38 MAPK and JNK activation was not affected by maternal exposure to LPS. These results indicate that MAPKs are differentially modulated by age and maternal exposure to LPS

Modulation of LPS-Induced Activation of Hepatic Map Kinases

Lipopolysaccharide (LPS) is a potent inflammagen that has been found to be primarily responsible for many symptoms caused by gram-negative bacterial infections. The LPS-initiated signal transduction pathways involve several terminal kinases, mainly p42/44 mitogen-activated protein kinase (MAPK), p38 MAPK and c-Jun N-terminal kinase (JNK), ultimately leading to increased expression of genes encoding such inflammatory cytokines as interleukin (IL )-1 �. IL-6 and tumor necrosis factors (TNF)-u. In this study, the effects of age on LPS-induced activation of MAPKs in the liver of rats were examined. Results show that the basal level of phosphorylated p42/44 MAPK was increased in postnatal day (P) 21 and P70 compared to P 1 animals treated with saline, and that LPS significantly increased the phosphorylation of p42/44 MAPK at P21 and P70. On the other hand, both basal and phosphorylated p38 MAPK did not show significant changes in P21 and P70 liver compared to PI. The effects of maternal exposure to LPS on the activation of MAPKs in P21 offspring liver were also examined. Results show that p42/44 MAPK activation was significantly decreased in the liver of pups born to LPS-treated dams as compared to those born to saline-treated dams following LPS stimulation. However, p38 MAPK and JNK activation was not affected by maternal exposure to LPS. These results indicate that MAPKs are differentially modulated by age and maternal exposure to LPS

Postnatal Development of Hepatic Innate Immune Response

The liver is an immunocompetent organ that plays a key role in the immune response to infections, and the development of hepatic immune function during early postnatal stages has not been thoroughly characterized. This study analyzed the constitutive expression of complement factors, namely C3 and C9, and pattern recognition receptors, namely CD14, toll-like receptor (TLR)-4, and lipopolysaccharide binding protein (LBP), in the liver of postnatal day (P)1, P21, and P70 rats, and compared the kinetics of induction of cytokines and chemokines in the liver of P 1 and P 21 animals. Our studies found that while the mRNA expression of C3, C9, CD14, and TLR-4 was lower in P1 animals, the mRNA level of LBP was higher in P1 animals as compared to older animals, and that the kinetics of induction of cytokines and chemokines was significantly delayed in P1 as compared to P21 liver following LPS stimulation. Our data suggest that hepatic innate immunity is deficient in the neonates and undergo significant development during early postnatal life

Biology of advanced uveal melanoma and next steps for clinical therapeutics.

Uveal melanoma is the most common intraocular malignancy although it is a rare subset of all melanomas. Uveal melanoma has distinct biology relative to cutaneous melanoma, with widely divergent patient outcomes. Patients diagnosed with a primary uveal melanoma can be stratified for risk of metastasis by cytogenetics or gene expression profiling, with approximately half of patients developing metastatic disease, predominately hepatic in location, over a 15-yr period. Historically, no systemic therapy has been associated with a clear clinical benefit for patients with advanced disease, and median survival remains poor. Here, as a joint effort between the Melanoma Research Foundation\u27s ocular melanoma initiative, CURE OM and the National Cancer Institute, the current understanding of the molecular and immunobiology of uveal melanoma is reviewed, and on-going laboratory research into the disease is highlighted. Finally, recent investigations relevant to clinical management via targeted and immunotherapies are reviewed, and next steps in the development of clinical therapeutics are discussed

Transcriptional analysis of metastatic uveal melanoma survival nominates NRP1 as a therapeutic target.

Uveal melanoma is a rare form of melanoma with particularly poor outcomes in the metastatic setting. In contrast with cutaneous melanoma, uveal melanoma lacks BRAF mutations and demonstrates very low response rates to immune-checkpoint blockade. Our objectives were to study the transcriptomics of metastatic uveal melanoma with the intent of assessing gene pathways and potential molecular characteristics that might be nominated for further exploration as therapeutic targets. We initially analyzed transcriptional data from The Cancer Genome Atlas suggesting PI3K/mTOR and glycolysis as well as IL6 associating with poor survival. From tumor samples collected in a prospective phase II trial (A091201), we performed a transcriptional analysis of human metastatic uveal melanoma observing a novel role for epithelial-mesenchymal transition associating with survival. Specifically, we nominate and describe initial functional validation of neuropillin-1 from uveal melanoma cells as associated with poor survival and as a mediator of proliferation and migration for uveal melanoma in vitro. These results immediately nominate potential next steps in clinical research for patients with metastatic uveal melanoma

Adjuvant crizotinib in high-risk uveal melanoma following definitive therapy

IntroductionApproximately 40% of patients with uveal melanoma (UM) will develop metastatic disease. Tumors measuring at least 12mm in basal diameter with a class 2 signature, as defined by a widely used gene expression-profiling test, are associated with significantly higher risk of metastasis, with a median time to recurrence of 32 months. No therapy has been shown to reduce this risk. Materials and MethodsThis was a single-arm, multicenter study in patients with high-risk UM who received definitive treatment of primary disease and had no evidence of metastasis. Patients were consecutively enrolled to receive 12 four-week cycles of adjuvant crizotinib at a starting dose of 250mg twice daily and were subsequently monitored for 36 months. The primary outcome of this study was to assess recurrence-free survival (RFS) of patients with high-risk UM who received adjuvant crizotinib. Results34 patients enrolled and received at least one dose of crizotinib. Two patients were unevaluable due to early withdrawal and loss to follow-up, leaving 32 patients evaluable for efficacy. Eight patients (25%) did not complete the planned 48-week course of treatment due to disease recurrence (n=5) or toxicity (n=3). All patients experienced at least one adverse event (AE), with 11/34 (32%) experiencing a Common Terminology Criteria for Adverse Events (CTCAE) grade 3 or 4 AE. After a median duration of follow up of 47.1 months, 21 patients developed distant recurrent disease. The median RFS was 34.9 months (95% CI (Confidence Interval), 23-55 months), with a 32-month recurrence rate of 50% (95% CI, 33-67%). Analysis of protein contents from peripheral blood extracellular vesicles in a subset of patient samples from baseline, on-treatment, and off-treatment, revealed a change in protein content associated with crizotinib exposure, however without a clear association with disease outcome. ConclusionsThe use of adjuvant crizotinib in patients with high-risk UM did not result in improved RFS when compared to historical controls. Analysis of blood extracellular vesicles revealed changes in protein content associated with treatment, raising the possibility of future use as a biomarker. Further investigation of adjuvant treatment options are necessary for this challenging disease