Glucocorticoids are potent immunosuppressants which work in part by inhibiting cytokine gene transcription. We show here that NF-B, an important regulator of numerous cytokine genes, is functionally inhibited by the synthetic glucocorticoid dexamethasone (DEX). In transfection experiments, DEX treatment in the presence of cotransfected glucocorticoid receptor (GR) inhibits NF-B p65-mediated gene expression and p65 inhibits GR activation of a glucocorticoid response element. Evidence is presented for a direct interaction between GR and the NF-B subunits p65 and p50. In addition, we demonstrate that the ability of p65, p50, and c-rel subunits to bind DNA is inhibited by DEX and GR. In HeLa cells, DEX activation of endogenous GR is sufficient to block tumor necrosis factor alpha or interleukin 1 activation of NF-B at the levels of both DNA binding and transcriptional activation. DEX treatment of HeLa cells also results in a significant loss of nuclear p65 and a slight increase in cytoplasmic p65. These data reveal a second mechanism by which NF-B activity may be regulated by DEX. We also report that RU486 treatment of wild-type GR and DEX treatment of a transactivation mutant of GR each can significantly inhibit p65 activity. In addition, we found that the zinc finger domain of GR is necessary for the inhibition of p65. This domain is also required for GR repression of AP-1. Surprisingly, while both AP-1 and NF-B can be inhibited by activated GR, synergistic NF-B/AP-1 activity is largely unaffected. These data suggest that NF-B, AP-1, and GR interact in a complex regulatory network to modulate gene expression and that cross-coupling of NF-B and GR plays an important role in glucocorticoid-mediated repression of cytokine transcription.Glucocorticoids have long been used as effective immunosuppressive agents in the treatment of conditions involving T-cell-or cytokine-mediated tissue damage. These steroids have been shown to block inflammation, suppress immune system activation, and act as growth-inhibitory agents both in vivo and in vitro (23). Surprisingly, despite the lengthy history of the use of glucocorticoids as therapeutic agents, the mechanism by which they perform these functions is largely unknown.Studies of the effect of glucocorticoid administration on the immune system have resulted in a number of important observations. Glucocorticoids induce a rapid redistribution of lymphocytes from the circulation to other lymphoid compartments (23). In addition, glucocorticoids potently suppress lymphocyte accessory function, the clonal expansion of T lymphocytes, and the secretion of cytokines (23, 73). Interestingly, cytotoxic Tlymphocyte clones provided with exogenous interleukin 2 (IL-2) are able to proliferate in response to mitogenic stimulation in the presence of glucocorticoids (28). These data suggest that the block of cytokine secretion plays an important role in glucocorticoid-mediated immunosuppression. Indeed, glucocorticoid administration represses the de novo transcription of a number of cytokine gene...

Hypertrophic cardiomyopathy (HCM) is an inherited form of heart disease that affects 1 in 500 individuals. Here it is shown that calcineurin, a calcium-regulated phosphatase, plays a critical role in the pathogenesis of HCM. Administration of the calcineurin inhibitors cyclosporin and FK506 prevented disease in mice that were genetically predisposed to develop HCM as a result of aberrant expression of tropomodulin, myosin light chain-2, or fetal beta-tropomyosin in the heart. Cyclosporin had a similar effect in a rat model of pressure-overload hypertrophy. These results suggest that calcineurin inhibitors merit investigation as potential therapeutics for certain forms of human heart disease.

Purpose: The insulin-like growth factor (IGF) signaling pathway is implicated in cellular mitogenesis, angiogenesis, tumor cell survival, and tumorigenesis. Inhibition of this pathway results in decreased cell growth, inhibition of tumor formation in animal models, and increased apoptosis in cells treated with cytotoxic chemotherapy. We generated and characterized a human monoclonal antibody that targeted the IGF receptor.Experimental Design: By use of XenoMouse technology, we generated CP-751,871, a fully human IgG2 antibody with high affinity (K d = 1.5 nmol/L) for human IGF-1R and evaluated its biological, pharmacologic, and antitumor properties.Results: This antibody blocks binding of IGF-1 to its receptor (IC 50 1.8 nmol/L), IGF-1-induced receptor autophosphorylation (IC 50 0.42 nmol/L) and induced the downregulation of IGF-1R in vitro and in tumor xenografts. The extent of IGF-1R down-regulation in vivo was proportional to CP-751,871 concentrations in the serum of tumor-bearing mice. Pharmacokinetic profiles in cynomolgus monkeys indicated a close to linear increase of exposure following i.v. dosing of antibody in the range of 3 to 100 mg/kg. CP-751,871 showed significant antitumor activity both as a single agent and in combination with Adriamycin, 5-fluorouracil, or tamoxifen in multiple tumor models. A biomarker assay was developed to establish the relationship between circulating antibody concentrations and down-regulation of IGF-1R in peripheral blood cells. The concentration of CP-751,871 required to down-regulate 50% of IGF-1R on peripheral blood cells was 0.3 nmol/L. Conclusion:These data suggest that inhibition of the IGF cascade by use of this monoclonal antibody may be of clinical benefit in the treatment of human cancers.

Preclinical evidence that targeting the insulin-like growth factor receptor (IGF-IR) is effective in cancer treatment has been accumulating for almost two decades. Efforts to develop drugs began in the late 1990s, and initial data from clinical trials were reported in 2006. The biological rationale for IGF-IR targeting has potential relevance to many tumor types, and early results have justified expanded programs to evaluate IGF-IR-targeting agents in many areas of clinical need. More than two dozen drug candidates have been developed and clinical trials are underway for at least 12 of these. Early clinical trials reveal an acceptable safety profile together with pharmacodynamic evidence that the receptor can be successfully targeted. It is premature to draw conclusions regarding efficacy, but well-documented instances of single-agent activity were noted during phase I evaluations, and recent evidence from a phase II study suggests that co-administration of an anti-IGF-IR antibody with chemotherapy for non-small-cell lung cancer improves objective response rate and progression-free survival. With more than 70 trials involving a variety of drug candidates underway, the IGF-IR is becoming one of the most intensively investigated molecular targets in oncology. Early results justify the continuation of ongoing research across a broad range of cancer indications.

SummaryBackground-Figitumumab is a fully human IgG2 monoclonal antibody targeting the insulin-like growth-factor-1 receptor (IGF-1R). Preclinical data suggest a dependence on insulin-like growthfactor signalling for sarcoma subtypes, including Ewing's sarcoma, and early reports show antitumour activity of IGF-1R-targeting drugs in these diseases.

Until recently, non-small-cell lung cancer (NSCLC) was treated as a single disease despite recognition of its histologic and molecular heterogeneity. Recent clinical trials, however, demonstrate that histology is an important factor for individualizing treatment, based on either safety or efficacy outcomes. For example, the labeling of the licensed agents bevacizumab and pemetrexed is restricted to patients with nonsquamous cell NSCLC. For bevacizumab, this restriction is due to an apparent association between squamous cell histology and severe pulmonary hemorrhage, whereas for pemetrexed, superior treatment effects have been observed in patients with nonsquamous cell histology. Given fewer agents are both active and tolerable in patients with squamous cell carcinoma compared with adenocarcinoma, and the nature of this particular phenotype of NSCLC, new drugs are needed for this histology. In this new histology-based treatment era, questions persist. Can pathology accurately distinguish the histologic subtypes of NSCLC? Can we use cytologic diagnosis? In the future, will molecular profiling of tumors trump histologic analysis? Herein we describe how therapy for NSCLC is evolving on the basis of a better understanding of molecular mechanisms underlying NSCLC histologic heterogeneity and tumorigenesis.

These data suggest that PCI(20) is safe and effective in patients with NSCLC.

Purpose: This phase I study was undertaken to define the maximum tolerated dose, safety, and pharmacokinetic profile of CP-751,871. Experimental Design: Using a rapid dose escalation design, patients with advanced nonhematologic malignancies were treated with CP-751,871 in four dose escalation cohorts. CP-751,871 was administered i.v. on day 1 of each 21-day cycle. Pharmacokinetic evaluation was done in all treatment cohorts during cycles 1and 4. Results: Twenty-four patients received 110 cycles at four dose levels. The maximum tolerated dose exceeded the maximal feasible dose of 20 mg/kg and, thus, was not identified. Treatment-related toxicities were generally mild. The most common adverse events were hyperglycemia, anorexia, nausea, elevated aspartate aminotransferase, elevated g-glutamyltransferase, diarrhea, hyperuracemia, and fatigue. At 20 mg/kg, 10 of 15 patients experienced stability of disease. Two of these patients experienced long-term stability. There were no objective responses. Pharmacokinetic analysis revealed a dose-dependent increase in CP-751,871 exposure and f2-fold accumulation on repeated dosing in 21-day cycles. Plasma concentrations of CP-751,871 attained were several log-fold greater than the biologically active concentration. Treatment with CP-751,871 increased serum insulin and human growth hormone levels, with modest increases in serum glucose levels. Conclusions: CP-751,871 has a favorable safety profile and was well tolerated when given in continuous cycles. At the maximal feasible dose of 20 mg/kg, there was a moderate accumulation in plasma exposure, and most of the treated patients experienced stability of disease.