Most evidence indicates that nitric oxide plays a role in normal wound repair; however, involvement of inducible nitric oxide synthase (iNOS) has not been established. Experiments were carried out to determine the requirement for iNOS in closing excisional wounds. Wound closure was delayed by 31% in iNOS knockout mice compared with wild-type animals. An identical delay in wound closure was observed in wild-type mice given a continuous infusion of the partially selective iNOS inhibitor N6-(iminoethyl)-L-lysine. Delayed wound healing in iNOS-deficient mice was completely reversed by a single application of an adenoviral vector containing human iNOS cDNA (AdiNOS) at the time of wounding. Reverse transcription PCR identified iNOS mRNA expression in wild-type mice peaking 4-6 d after wounding, and confirmed expression of human iNOS in the adenoviral vector containing human iNOS cDNA-treated animals. These results establish the key role of iNOS in wound closure, and suggest a gene therapy strategy to improve wound healing in iNOS-deficient states such as diabetes, and during steroid treatment.
A role for nitric oxide (NO) in wound healing has been proposed; however, the absolute requirement of NO for wound healing in vivo and the contribution of endothelial NO synthase (eNOS) have not been determined. Experiments were carried out using eNOS gene knockout (KO) mice to determine the requirement for eNOS on wound closure and wound strength. Excisional wound closure was significantly delayed in the eNOS KO mice (29.4 +/- 2.2 days) compared with wild-type (WT) controls (20.2 +/- 0.4 days). At 10 days, incisional wound tensile strength demonstrated a 38% reduction in the eNOS KO mice. Because effective wound repair requires growth factor-stimulated angiogenesis, in vitro and in vivo angiogenesis assays were performed in the mice to assess the effects of eNOS deficiency on angiogenesis. Endothelial cell sprouting assays confirmed in vitro that eNOS is required for proper endothelial cell migration, proliferation, and differentiation. Aortic segments harvested from eNOS KO mice cultured with Matrigel demonstrated a significant reduction in endothelial cell sprouting and [(3)H]thymidine incorporation compared with WT mice at 5 days. Capillary ingrowth into subcutaneously implanted Matrigel plugs was significantly reduced in eNOS KO mice (2.67 +/- 0.33 vessels/plug) compared with WT mice (10.17 +/- 0.79 vessels/plug). These results clearly show that eNOS plays a significant role in facilitating wound repair and growth factor-stimulated angiogenesis.
We evaluated neoadjuvant ipilimumab in patients with surgically operable regionally advanced melanoma in order to define markers of activity in the blood and tumor as assessed at baseline (before ipilimumab) and early on-treatment. Patients were treated with ipilimumab (10 mg/kg intravenously every 3 weeks ×2 doses) bracketing surgery. Tumor and blood biospecimens were obtained at baseline and at surgery. Flow cytometry and immunohistochemistry for select biomarkers were performed. Thirty five patients were enrolled; IIIB (3; N2b), IIIC (32; N2c, N3), IV (2). Worst toxicities included Grade 3 diarrhea/colitis (5; 14%), hepatitis (2; 6%), rash (1; 3%), elevated lipase (3; 9%). Median follow up was 18 months: among 33 evaluable patients, median progression free survival (PFS) was 11 months, 95% CI (6.2–19.2). There was a significant decrease in circulating myeloid derived suppressor cells (MDSC). Greater decrease in circulating monocyte gate MDSC Lin1−/HLA-DR−/CD33+/CD11b+ was associated with improved PFS (p = 0.03). There was a significant increase in circulating regulatory T cells (Treg; CD4+CD25hi+Foxp3+) that, unexpectedly, was associated with improved PFS (HR = 0.57; p = 0.034). Baseline evidence of fully activated type I CD4+ and CD8+ antigen-specific T cell immunity against cancer-testis (NY-ESO-1) and melanocytic lineage (MART-1, gp100) antigens was detected and was significantly potentiated after ipilimumab. In tumor, there was a significant increase in CD8+ T cells after ipilimumab (p = 0.02). Ipilimumab induced increased tumor infiltration by fully activated (CD69+) CD3+/CD4+ and CD3+/CD8+ T cells with evidence of induction/potentiation of memory T cells (CD45RO+). The change in Treg observed within the tumor showed an inverse relationship with clinical benefit and greater decrease in tumor MDSC subset Lin1−/HLA-DR−/CD33+/CD11b+ was associated with improved PFS at one year. Neoadjuvant evaluation revealed a significant immunomodulating role for ipilimumab on Treg, MDSC and effector T cells in the circulation and tumor microenvironment that warrants further pursuit in the quest for optimizing melanoma immunotherapy.
Neoadjuvant HDI is highly effective for the treatment of palpable stage IIIB-C melanoma, and the findings of this study implicate an indirect immunomodulatory mechanism rather than a direct antitumor mechanism.
Purpose: Interferon (IFN)-a2b is the only Food and Drug Administration^approved treatment for operable high-risk melanoma that has been shown to significantly and durably prolong relapse-free survival (RFS) of patients with stage IIB-III melanoma. Development of reliable serum assays may contribute to the development of methods for earlier detection of melanoma and the selection of patients who may be most susceptible to current available interventions with IFNa. Experimental Design: A powerful high-throughput xMAP multiplex immunobead assay technology (Luminex Corp., Austin, TX) was used to simultaneously test 29 cytokines, chemokines, angiogenic as well as growth factors, and soluble receptors in the sera of 179 patients with high-risk melanoma and 378 healthy individuals. Results: Serum concentrations of interleukin (IL)-1a, IL-1h, IL-6, IL-8, IL-12p40, IL-13, granulocyte colony-stimulating factor, monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein (MIP)-1a, MIP-1h, IFNa, tumor necrosis factor (TNF)-a, epidermal growth factor, vascular endothelial growth factor (VEGF), and TNF receptor II were found to be significantly higher in patients with resected high-risk melanoma compared with healthy controls. Bayesian Network algorithm classification of the data offered 90% sensitivity at 98% specificity with 96.5% of melanoma patients distinguished from healthy individuals. IFN-a2b therapy resulted in a significant decrease of serum levels of immunosuppressive and tumor angiogenic/ growth stimulatory factors (VEGF, epidermal growth factor, and hepatocyte growth factor) and increased levels of antiangiogenic IFN-g inducible protein 10 (IP-10) and IFN-a. Pretreatment levels of proinflammatory cytokines IL-1h, IL-1a, IL-6, TNF-a, and chemokines MIP-1a and MIP-1h were found to be significantly higher in the serum of patients with longer RFS values of 1to 5 and >5 years when compared with patients with shorter RFS of <1year.Conclusion: These data show that multiplexed analysis of serum biomarkers is useful for the evaluation of prognostic markers of clinical outcome and potential predictive markers of response to IFN-a2b in patients with high-risk operable melanoma.Melanoma is a potentially lethal malignancy that has shown an increase in incidence that exceeds all other solid tumors. It accounts for >79% of skin cancer -related deaths. Melanoma is surgically curable when discovered at early stages; however, once regional and systemic spread of the disease occurs, the prognosis is more ominous. Patients with localized nonulcerated primary melanoma of <1 mm Breslow depth (stage IA) at the time of diagnosis have an excellent prognosis, but those with primary melanoma of a Breslow depth >4 mm (stage IIB) or regional lymph node metastasis (stage III) have intermediate-to-high risk of relapse, and those with distant metastases have a median survival of 5 to 11 months (1 -6).
Purpose: The Janus-activated kinase/signal transducers and activators of transcription (STAT) pathway of IFN signaling is important to immunoregulation and tumor progression. STAT1plays a prominent role in the effector immune response, whereas STAT3 is implicated in tumor progression and down-regulation of the response to type IIFNs.The goal of this study was to understand the effects of high-dose IFNa2b (HDI) in relation to the balance of pSTAT1and pSTAT3. Experimental Design: We evaluated STAT1 and STAT3 jointly as mediators of IFNa effects in the setting of a prospective neoadjuvant trial of HDI, in which tissue samples were obtained before and after 20 doses of HDI therapy. Double immunohistochemistry for pSTAT1and pSTAT3 was done on paired fixed (9 patients) or frozen (12 patients) biopsies. Results: HDI was found to up-regulate pSTAT1, whereas it down-regulates pSTAT3 and total STAT3 levels in both tumor cells and lymphocytes. Higher pSTAT1/pSTAT3 ratios in tumor cells pretreatment were associated with longer overall survival (P = 0.032). The pSTAT1/pSTAT3 ratios were augmented by HDI both in melanoma cells (P = 0.005) and in lymphocytes (P = 0.022). Of the immunologic mediators and markers tested,TAP2 was augmented by HDI (but not TAP1and MHC class I/II). Conclusion: IFNa2b significantly modulates the balance of STAT1/STAT3 in tumor cells and host lymphocytes, leading to up-regulation of TAP2 and augmented host antitumor response. The pSTAT1/pSTAT3 ratio in tumor cells at baseline may serve as a useful predictor of clinical outcome in cutaneous melanoma; the modulation of this ratio may serve as a predictor of therapeutic effect.High-dose IFNa2b (HDI) is the only therapy that has shown a reproducible ability to prolong both relapse-free and overall survival of patients with resected high-risk, deep, primary, or lymph node metastatic melanoma. This therapy has consistently shown a capacity to reduce the hazard of relapse and mortality by 22% to 33% in multiple U.S. intergroup studies done over the past 20 years (1 -3). However, in the past decade, no further progress in the adjuvant therapy of melanoma has occurred, and the gap in our knowledge of the IFNa2b mechanism has proven to be a major impediment to further progress. A better understanding of the mechanism(s) of HDI in the adjuvant therapy of melanoma would enable more effective application of this therapy, and more intelligent strategies building upon this modality.The antitumor effects of IFNa2b include direct inhibition of tumor cell growth and the modulation of host immune response to tumor. The Janus-activated kinase/signal transducers and activators of transcription (STAT) signal pathway is one of the major mechanisms of IFNa2b action. Both human type I IFNa receptor chains 1 and 2 are required for the type I IFN -dependent signaling pathways. The intracellular domains of these receptors are associated with Janus-activated kinases, which are activated upon IFNa2b binding to its receptors. Janus-activated kinases then phosphorylate ...
Our results confirm that some of these spitzoid lesions metastasize to regional lymph nodes and SLNB is a valuable adjunct tool in staging these lesions. However, molecular studies and a prolonged follow-up are needed to determine whether these lesions, especially those occurring in children are comparable to stage matched overt melanoma in adults.
Background: The prognosis for malignant gliomas remains dismal. We addressed the safety, feasibility and preliminary clinical activity of the vaccinations using autologous glioma cells and interleukin (IL)-4 gene transfected fibroblasts.
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