Tumor cell SYK expression modulates the tumor immune microenvironment composition in human cancer via TNF-α dependent signaling

BACKGROUND

The expression of SYK in cancer cells has been associated with both tumor promoting and tumor suppressive effects. Despite being proposed as anticancer therapeutic target, the possible role of SYK in modulating local adaptive antitumor immune responses remains uncertain. Using detailed analysis of primary human tumors and in vitro models, we reveal the immunomodulatory effect of SYK protein in human solid cancer.

METHODS

We spatially mapped SYK kinase in tumor cells, stromal cells and tumor-infiltrating leukocytes (TILs) in 808 primary non-small cell lung carcinomas (NSCLCs) from two cohorts and in 374 breast carcinomas (BCs) from two independent cohorts. We established the associations of localized SYK with clinicopathologic variables and outcomes. The immunomodulatory role of SYK on tumor cells was assessed using in vitro cytokine stimulation, transcriptomic analysis and selective SYK blockade using a small molecule inhibitor. Functional responses were assessed using cocultures of tumor cells with peripheral blood lymphocytes. T cell responses in baseline and post-treatment biopsies from patients with BC treated with a SYK inhibitor in a phase I clinical trial were also studied.

RESULTS

Elevated tumor cell or leukocyte SYK expression was associated with high CD4⁺ and CD8⁺ TILs and better outcome in both NSCLC and BC. Tumor cell SYK was associated with oncogenic driver mutations in EGFR or KRAS in lung adenocarcinomas and with triple negative phenotype in BC. In cultured tumor cells, SYK was upregulated by TNFα and required for the TNFα-induced proinflammatory responses and T cell activation. SYK blockade after nivolumab in a phase I clinical trial including three patients with advanced triple negative BC reduced TILs and T cell proliferation. Our work establishes the proinflammatory function of tumor cell SYK in lung and breast cancer. SYK signaling in cultured tumor cells is required for T cell activation and SYK blockade limits adaptive antitumor immune responses and tumor rejection in patients with cancer.

CONCLUSIONS

Together, our results establish the immunomodulatory role of SYK expression in human solid tumors. This information could be used to develop novel biomarkers and/or therapeutic strategies.

Response to brentuximab vedotin versus physician's choice by CD30 expression and large cell transformation status in patients with mycosis fungoides: An ALCANZA sub-analysis

INTRODUCTION

Mycosis fungoides (MF), the most common type of cutaneous T-cell lymphoma, can lead to disfiguring lesions, debilitating pruritus and frequent skin infections. This study assessed response to brentuximab vedotin in patients with MF in the phase III ALCANZA study.

METHODS

Baseline CD30 levels and large-cell transformation (LCT) status were centrally reviewed in patients with previously-treated CD30-positive MF using ≥2 skin biopsies obtained at screening; eligible patients required ≥1 biopsy with ≥10% CD30 expression. Patients were categorised as CD30_min < 10% (≥1 biopsy with <10% CD30 expression), or CD30_min ≥ 10% (all biopsies with ≥10% CD30 expression) and baseline LCT present or absent. Efficacy analyses were the proportion of patients with objective response lasting ≥4 months (ORR4) and progression-free survival (PFS).

RESULTS

Clinical activity with brentuximab vedotin was observed across all CD30 expression levels in patients with ≥1 biopsy showing ≥10% CD30 expression. Superior ORR4 was observed with brentuximab vedotin versus physician's choice in patients: with CD30_min < 10% (40.9% versus 9.5%), with CD30_min ≥ 10% (57.1% versus 10.3%), with LCT (64.7% versus 17.6%) and without LCT (38.7% versus 6.5%). Brentuximab vedotin improved median PFS versus physician's choice in patients: with CD30_min < 10% (16.7 versus 2.3 months), with CD30_min ≥ 10% (15.5 versus 3.9 months), with LCT (15.5 versus 2.8 months) and without LCT (16.1 versus 3.5 months). Safety profiles were generally comparable across subgroups.

CONCLUSION

These exploratory analyses demonstrated that brentuximab vedotin improved rates of ORR4 and PFS versus physician's choice in patients with CD30-positive MF and ≥1 biopsy showing ≥10% CD30 expression, regardless of LCT status.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov, NCT01578499.

Response to A+CHP by CD30 expression in the ECHELON-2 trial

7538

Background: Brentuximab vedotin (BV) is an antibody-drug conjugate that targets CD30. The ECHELON-2 (E-2) study demonstrated significantly longer progression-free and overall survival with BV plus cyclophosphamide, doxorubicin, and prednisone (A+CHP) versus CHOP in frontline treatment of patients (pts) with CD30+ peripheral T-cell lymphoma (PTCL). Complete remission (CR) rate (A+CHP 68%; CHOP 56%) and objective response rate (ORR) (A+CHP 83%; CHOP 72%) were also significantly increased. Expression of CD30 is universal in systemic anaplastic large-cell lymphoma (sALCL) but variable among non-sALCL subtypes. As ORR is a direct measure of antitumor activity, we examined response to A+CHP by CD30 expression. Methods: Pts with CD30+ (≥10% by local review) PTCL were included in E-2. Eligible histologies included ALK+ sALCL (IPI ≥2), ALK− sALCL, PTCL-not otherwise specified (PTCL-NOS), angioimmunoblastic T-cell lymphoma (AITL), adult T-cell leukemia/lymphoma, enteropathy-associated T-cell lymphoma, and hepatosplenic T-cell lymphoma. We analyzed the relationship between CD30 expression (IHC Ber H2 antibody) above and below the median (median CD30=18% PTCL-NOS; 25% AITL) and CR rate, ORR, and duration of CR (DOCR) in pts with AITL and PTCL-NOS treated with A+CHP. Results: Most (26/29, 90%) AITL pts had CD30 expression between 10% and 30%. PTCL-NOS pts were more evenly distributed across levels of CD30 expression ranging from 10% to 100%. CD30 levels were neither predictive of response (Table) nor significantly associated with DOCR in pts with AITL (P=0.30) or PTCL-NOS (P=0.90) (log-rank test). Response by CD30 expression. Clinical trial information: NCT01777152. Conclusions: CD30 expression above vs below median (or at 10%) did not predict response to A+CHP in E-2 non-ALCL subtypes, as responses were seen across CD30 levels. This may be due to intra- and inter-tumoral heterogeneity of CD30 expression, limitations of IHC, the nature of CD30 on the cell surface, and multiple mechanisms of action of BV. Further evaluation of the expression-response relationship in PTCL pts with CD30 <10% is warranted.[Table: see text]

Consistent expression of guanylyl cyclase-C in primary and metastatic gastrointestinal cancers

BACKGROUND

The transmembrane receptor guanylate cyclase-C (GCC) has been found to be expressed in colorectal cancers. However, limited data are available on GCC protein expression in non-colorectal gastrointestinal tumors and few studies have reported whether GCC protein expression was consistently preserved in synchronous primary and metastatic cancer tissues.

METHODS

GCC protein status was assessed by immunohistochemistry in tumor specimens from individuals (n = 627) with gastrointestinal tumors, including esophageal (n = 130), gastric (n = 276), pancreatic (n = 136), and colorectal (n = 85) primary and metastatic tumors. Tissue specimens consisted of tissue microarrays containing esophageal, gastric, pancreatic tumors, and whole-slide tissue sections from colorectal cancer patients with matching primary and metastatic tumors.

RESULT

Among the evaluated esophageal, gastric, and pancreatic tumors, the frequency of GCC positivity at the protein level ranged from 59% to 68%. GCC was consistently expressed in primary and matched/synchronous metastatic lesions of colorectal cancer tissues derived from the same patients.

CONCLUSION

This observational study demonstrated the protein expression of GCC across various gastrointestinal malignancies. In all cancer histotypes, GCC protein localization was observed predominantly in the cytoplasm compared to the membrane region of tumor cells. Consistent immunohistochemistry detection of GCC protein expression in primary colorectal cancers and in their matched liver metastases suggests that the expression of GCC is maintained throughout the process of tumor progression and formation of metastatic disease.

Brentuximab vedotin or physician's choice in CD30-positive cutaneous T-cell lymphoma (ALCANZA): an international, open-label, randomised, phase 3, multicentre trial

BACKGROUND

Cutaneous T-cell lymphomas are rare, generally incurable, and associated with reduced quality of life. Present systemic therapies rarely provide reliable and durable responses. We aimed to assess efficacy and safety of brentuximab vedotin versus conventional therapy for previously treated patients with CD30-positive cutaneous T-cell lymphomas.

METHODS

In this international, open-label, randomised, phase 3, multicentre trial, we enrolled adult patients with CD30-positive mycosis fungoides or primary cutaneous anaplastic large-cell lymphoma who had been previously treated. Patients were enrolled across 52 centres in 13 countries. Patients were randomly assigned (1:1) centrally by an interactive voice and web response system to receive intravenous brentuximab vedotin 1·8 mg/kg once every 3 weeks, for up to 16 3-week cycles, or physician's choice (oral methotrexate 5-50 mg once per week or oral bexarotene 300 mg/m² once per day) for up to 48 weeks. The primary endpoint was the proportion of patients in the intention-to-treat population achieving an objective global response lasting at least 4 months per independent review facility. Safety analyses were done in all patients who received at least one dose of study drug. This trial was registered with ClinicalTrials.gov, number NCT01578499.

FINDINGS

Between Aug 13, 2012, and July 31, 2015, 131 patients were enrolled and randomly assigned to a group (66 to brentuximab vedotin and 65 to physician's choice), with 128 analysed in the intention-to-treat population (64 in each group). At a median follow-up of 22·9 months (95% CI 18·4-26·1), the proportion of patients achieving an objective global response lasting at least 4 months was 56·3% (36 of 64 patients) with brentuximab vedotin versus 12·5% (eight of 64) with physician's choice, resulting in a between-group difference of 43·8% (95% CI 29·1-58·4; p<0·0001). Grade 3-4 adverse events were reported in 27 (41%) of 66 patients in the brentuximab vedotin group and 29 (47%) of 62 patients in the physician's choice group. Peripheral neuropathy was seen in 44 (67%) of 66 patients in the brentuximab vedotin group (n=21 grade 2, n=6 grade 3) and four (6%) of 62 patients in the physician's choice group. One of the four on-treatment deaths was deemed by the investigator to be treatment-related in the brentuximab vedotin group; no on-treatment deaths were reported in the physician's choice group.

INTERPRETATION

Significant improvement in objective response lasting at least 4 months was seen with brentuximab vedotin versus physician's choice of methotrexate or bexarotene.

FUNDING

Millennium Pharmaceuticals Inc (a wholly owned subsidiary of Takeda Pharmaceutical Company Ltd), Seattle Genetics Inc.

Outcomes by CD30 expression in patients with CTCL receiving brentuximab vedotin (BV) vs physician's choice (PC) in the Phase 3 ALCANZA study

7517

Background: The Phase 3 ALCANZA study showed significant, durable responses with CD30-directed antibody-drug conjugate BV vs PC of methotrexate (MTX) or bexarotene (Bex) for CD30-positive (CD30+) cutaneous T cell lymphoma (CTCL). Uniform CD30 expression is characteristic of primary cutaneous anaplastic large cell lymphoma (pcALCL), but is variable among other subtypes including mycosis fungoides (MF). We examined activity of BV and MTX / Bex by CD30 expression in pts treated on the ALCANZA study. Methods: Adults with previously treated CD30+ MF or pcALCL were enrolled. MF pts had ≥2 skin biopsies from separate lesions, pcALCL had ≥1. Patients were scored CD30+ if ≥1 biopsy had ≥10% CD30+ lymphoid cells using an investigational Ventana diagnostic test, centrally assessed by one pathologist. We compared the proportion of MF subgroup pts (n=50 per treatment arm) with objective response lasting ≥4 months (ORR4; ALCANZA primary endpoint) and PFS in pts with all biopsies ≥10% CD30+ (CD30min ≥10%) vs ≥1 biopsy <10% CD30+ (CD30min <10%). Pts were randomized 1:1 to BV 1.8 mg/kg IV, Q3W, or PC for up to 16 three-week cycles. Results: 125/184 (68%) MF and 44/47 (94%) pcALCL pts were screened and scored CD30+. High inter-lesional variability in CD30 expression was seen in MF pts; 55/125 CD30+ MF pts (44%) had ≥1 biopsy with low (<10%) or undetectable CD30. 100/125 CD30+ MF pts were eligible and enrolled. In the BV arm, ORR4 was higher in MF pts with CD30min ≥10% vs <10%; median PFS with BV was higher in the CD30min <10% group (Table). ORR4 with BV was greater than PC over all CD30 expression ranges (CD30min <5%, 38% vs 13%; CD30 ≥5–≤20%, 35% vs 10%; CD30 >20%, 76% vs 7%, respectively). Conclusions: Notable inter-patient or inter-lesional variability in CD30 expression was seen in MF pts. Highly superior ORR4 and PFS endpoints were seen with BV over PC regardless of CD30min expression level. Clinical trial information: NCT01578499. [Table: see text]

Use of the Total Cancer Care System to Enrich Screening for CD30-Positive Solid Tumors for Patient Enrollment Into a Brentuximab Vedotin Clinical Trial: A Pilot Study to Evaluate Feasibility

Background

One approach to identify patients who meet specific eligibility criteria for target-based clinical trials is to use patient and tumor registries to prescreen patient populations.

Objective

Here we demonstrate that the Total Cancer Care (TCC) Protocol, an ongoing, observational study, may provide a solution for rapidly identifying patients with CD30-positive tumors eligible for CD30-targeted therapies such as brentuximab vedotin.

Methods

The TCC patient gene expression profiling database was retrospectively screened for CD30 gene expression determined using HuRSTA-2a520709 Affymetrix arrays (GPL15048). Banked tumor tissue samples were used to determine CD30 protein expression by semiquantitative immunohistochemistry. Statistical comparisons of Z- and H-scores were performed using R statistical software (The R Foundation), and the predictive value, accuracy, sensitivity, and specificity of CD30 gene expression versus protein expression was estimated.

Results

As of March 2015, 120,887 patients have consented to the institutional review board–approved TCC Protocol. A total of 39,157 fresh frozen tumor specimens have been collected, from which over 14,000 samples have gene expression data available. CD30 RNA was expressed in a number of solid tumors; the highest median CD30 RNA expression was observed in primary tumors from lymph node, soft tissue (many sarcomas), lung, skin, and esophagus (median Z-scores 1.011, 0.399, 0.202, 0.152, and 1.011, respectively). High level CD30 gene expression significantly enriches for CD30-positive protein expression in breast, lung, skin, and ovarian cancer; accuracy ranged from 72% to 79%, sensitivity from 75% to 100%, specificity from 70% to 76%, positive predictive value from 20% to 40%, and negative predictive value from 95% to 100%.

Conclusions

The TCC gene expression profiling database guided tissue selection that enriched for CD30 protein expression in a number of solid tumor types. Such an approach may improve screening efficiency for enrolling patients into biomarker-based clinical trials.

Abstract B1-59: Identification of key molecular characteristics for achieving increased anti-tumor activity by combined mTORC1/2 and MEK1/2 investigational agents

The development of combination therapies is important to cancer treatment due to the potential to target multiple oncogenic pathways together, which may lead to enhanced anti-tumor activity and decreased chance for resistance. The RAS/RAF/MEK/ERK (MAP kinase) and PI3K/AKT/mTOR pathways are well-known pathways driving the oncogenic process in many cancer types; therefore, the simultaneous inhibition of these pathways may produce increased anti-tumor activity. It is important to find ideal cancer indications and molecular subtypes that may be most sensitive to drug combination inhibiting these pathways; this requires understanding of the molecular and genetic underpinnings. In this study, an in-vitro cell viability assay on 240 cancer cell lines was used to reveal the synergy mechanisms of the combination of investigational agents MLN0128 (mTORC1/2 inhibitor) with TAK733 (MEK1/2 inhibitor). Cells were administered with MLN0128 and TAK733 in DMSO in ten 2-fold serial dilutions and cell viability was measured using Promega's CellTiter-GLO® assay after a 72 hour incubation period. The 100 data points (10×10) were fit to a 9-parameter model to obtain a response surface for each cell line and the effect of the combined administration was measured using a non-linear blending score. Our previous study found that genes in the MAP kinase pathway such as KRAS, NRAS, or BRAF were mutated in cell lines demonstrating synergy. In this study, a 76-gene expression signature was additionally identified using a regression-based analysis. The 76 mRNAs include some genes within the two oncogenic pathways, as well as those that regulate feedback of the MAP kinase pathway and cross-talk between the pathways. A pathway and protein-protein interaction network-based analysis of the 76-gene signature and mutated genes suggest that the activation of the MAP kinase pathway in cells originally resistant to MLN0128 may be essential for a synergistic outcome from the MLN0128 and TAK733 combination. Cell lines with activating mutations or over-expressed genes in MAP kinase pathway are generally sensitive to TAK733 administration; these cell lines also demonstrated synergy to the combination of MLN0128 and TAK733. On the other hand, cell lines with highly expressed PI3K tend to antagonistically respond to the combination. In conclusion, our study suggests the key molecular conditions of cell lines in order to achieve increased anti-tumor activity by the combination of MLN0128 and TAK733. These findings can be utilized to establish a better-differentiated strategy in terms of patient stratification for the combination therapy using MLN0128 and TAK733.

Citation Format: Hyunjin Shin, Andrew Krueger, Bin Li, Derek Blair, William L. Trepicchio, Jeffrey Ecsedy. Identification of key molecular characteristics for achieving increased anti-tumor activity by combined mTORC1/2 and MEK1/2 investigational agents. [abstract]. In: Proceedings of the AACR Special Conference on Computational and Systems Biology of Cancer; Feb 8-11 2015; San Francisco, CA. Philadelphia (PA): AACR; Cancer Res 2015;75(22 Suppl 2):Abstract nr B1-59.

Abstract B28: Identification of drug-response biomarkers for combined mTORC1/2 and MEK1/2 investigational agents using a large-scale cancer cell line screen

Combination therapy in oncology drug development has the potential to overcome resistance against single agent-based therapy. In many cancers, the RAS/RAF/MEK/ERK and PI3K/AKT/mTOR pathways confer major cell growth and survival mechanisms. Therefore, a greater treatment effect may be achieved by inhibiting both pathways simultaneously through drug combination. In this study, the enhanced anti-proliferative activity of investigational drug MLN0128 (mTORC1/2 investigational agent) when combined with TAK733 (MEK1/2 investigational agent) was assessed using an in-vitro cell viability assay on 240 cancer cell lines. Cells were administered with MLN0128 and TAK-733 in DMSO in ten 2-fold serial dilutions and cell viability was measured using Promega's CellTiter-GLO® assay after a 72 hour incubation period. The data points were fit to a 9-parameter model to obtain a response surface and the effect of the combined administration for each cell line was measured using a non-linear blending score estimated from the response surface. Statistical analysis was conducted to determine if the estimated combination effect was associated with known mutated oncogenes, tumor suppressor genes, or cancer histology reports of the 240 cell lines. Interestingly, the synergy of combined agents appeared to be mainly driven by TAK733, as cell lines sensitive to TAK733 as a single agent demonstrated beneficial combination effect with the addition of MLN0128. Furthermore, cell lines with mutations in KRAS, NRAS, and BRAF showed greater synergy scores of the combination. Likewise, cell lines of colon, pancreatic, and skin origins were more sensitive to the combination. Of particular interest are cell lines with mutated KRAS/NRAS or colon origins since they were generally resistant to single agent MLN0128, but became sensitized to the combination with TAK733. In conclusion, our study of drug combination assays on a large-scale in-vitro cell line panel revealed that mutant KRAS/NRAS or colorectal cancers may be sensitive to combined MLN0128 with TAK733.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):B28.

Citation Format: Hyunjin Shin, Derek Blair, Bin Li, Greg Hather, William L. Trepicchio, Jeffrey Ecsedy, Esha Gangolli. Identification of drug-response biomarkers for combined mTORC1/2 and MEK1/2 investigational agents using a large-scale cancer cell line screen. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr B28.

Abstract A41: Validated immunohistochemistry assay for measuring total Aurora A kinase protein levels in FFPE human tumors

Aurora A kinase (AURKA) is a serine threonine kinase that plays a critical role in regulating mitotic progression during the cell cycle. Numerous reports have shown that AURKA is frequently activated in a multitude of tumor indications. The activation of AURKA can occur either at the chromosome level with gene amplification and/or at the protein level with overexpression. The overexpression of AURKA in tumors has been linked to the etiology of some cancers and to a worsened prognosis in patients. Detection of AURKA protein in these previous studies by immunohistochemistry (IHC) on human tumors has not been done using a standardized validated assay. This presents a challenge in comparing AURKA protein expression data across numerous studies. Published reports have noted AURKA protein levels in tumors ranging from 15% to as high as 94% depending on the tumor type. Evaluation of the staining pattern in these reports raised the question of whether this is true AURKA staining that is being detected, and whether it would be anticipated that a mitotic kinase with predominant expression during mitosis would be this prevalent in these tissues.

In order to better understand the protein expression level of total AURKA in human tumors, we developed an IHC assay for AURKA that could be used on formalin fixed paraffin embedded (FFPE) tissue. Initially, 4 different AURKA primary antibodies (Epitomics, Leica Microsystems (Novocastra), CST, and Becton Dickenson) were evaluated by Western blot analysis on lysates from asynchronous and nocadazole treated cells to estimate the specificity of each antibody. Matched frozen and FFPE human tumors were then measured by western blot and IHC respectively for AURKA protein levels to establish concordance between the two methods. Testing on additional human FFPE tumors and 5 different tissue micro arrays (TMA) were done to assess AURKA levels. The normalization of AURKA expression to the mitotic index of the tumor, was done by developing this IHC assay into a two color assay to also measure the mitotic marker phospho(Ser10) histone H3 (pHH3).

The Novocastra and Epitomics antibodies produced a specific band for AURKA and a proper modulation of AURKA when comparing asynchronous and nocodazole treated cells by Western blot analysis. The Novocastra antibody showed the best concordance by Western blot and IHC when comparing total AURKA expression in matched frozen and FFPE tumors. Further optimization of the total AURKA protein IHC assay was done using the Novocastra antibody. Testing of TMAs using this new assay demonstrated substantially lower percent positive AURKA expression compared to published reports: breast (35%), colon (32%), lung (39%), ovarian (12%), and prostate (7%). While there may be certain differences between the tumor indications tested here and those in the literature based on grade, stage and/or histological subtype, the IHC assay used here gives robust staining representative of total AURKA expression. Further, the AURKA protein level can now be normalized to the mitotic index by concurrently measuring the pHH3 level in tumors. This dual assay is now being used to assess AURKA protein expression and mitotic index in patient tumors from clinical studies with the first in class AURKA inhibitor alisertib.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr A41.

Evaluation of BRAF V600E mutation detection assays for purpose of clinical tumor sample analysis

Background: The RAS-RAF-MEK-ERK protein kinase pathway regulates multiple processes required for cell survival and proliferation. Aberrant activation of this pathway via somatic mutations is frequently found in tumors and leads to uncontrolled cell growth. Inhibiting MEK has been shown to impair proliferation and induce apoptosis of tumor cells, thus making MEK an attractive therapeutic target. Consequently, there are several MEK inhibitors currently under clinical investigation, including TAK-733, a novel non-ATP-competitive allosteric selective inhibitor of MEK. A common mutation has been identified in the BRAF gene, resulting in a valine &gt; glutamic acid substitution (A&gt;T nucleotide change) at amino acid 600 (V600E). This specific aberration accounts for ~90% of BRAF mutations, and leads to constitutive activation of the BRAF kinase. Studies have demonstrated that cell lines and xenograft models with the BRAF V600E mutation are more sensitive to MEK inhibition than wild-type tumor cells. Thus, it is important to be able to accurately assess patients’ BRAF V600E mutation status as part of a MEK-inhibitor drug development program.

Aims: The goal of this study was to assess the relative sensitivity of three different genotyping technology platforms for BRAF V600E mutation detection and to evaluate the performance of the genotyping assays on clinical melanoma samples.

Materials and Methods: DNA was extracted from cell pellets obtained from Millennium Pharmaceuticals’ cell bank of genetically characterized lines. The cell line DNA was diluted to produce samples with known ratios of V600E mutant (both homozygous and heterozygous) and wild-type alleles. These samples were tested in order to assess the sensitivity of three mutation detection technology platforms: direct sequencing, allelic discrimination PCR, and the real-time PCR based B-RAF Mutation Test Kit from DxS Ltd (Manchester, UK). To evaluate assay performance in clinically relevant samples, 15 formalin fixed paraffin embedded (FFPE) clinical melanoma samples were obtained from ProteoGenex, Inc. (Culver City, CA). The melanoma tumor blocks were cut and mounted onto slides in 5 µM sections. DNA was extracted, quantitated, and subsequently tested for the BRAF V600E mutation using both the DxS and allelic discrimination assays.

Results: The DxS Test Kit was able to detect the homozygous V600E mutation in samples with 1% or greater mutant DNA and the heterozygous mutation in samples with 5% or greater mutant DNA. The allelic discrimination assay was able to detect the homozygous and heterozygous V600E mutation in samples with 10% and 25% mutant DNA, respectively. Sanger sequencing was able to detect the homozygous and heterozygous V600E mutation in samples with 25% and 100% mutant DNA, respectively. Results from both the DxS and allelic discrimination assays were in complete concordance when testing clinical melanoma samples, and indicated that 9/15 samples (60%) contained the BRAF V600E mutation.

Summary: The DxS research-only assay for BRAF V600E mutation detection is the most sensitive genotyping method assessed in this study. Both the allelic discrimination and the DxS BRAF V600E mutation detection assays are fit for the purpose of analyzing clinical melanoma samples.

Molecular profile of peripheral blood mononuclear cells from patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory arthritis. Currently, diagnosis of RA may take several weeks, and factors used to predict a poor prognosis are not always reliable. Gene expression in RA may consist of a unique signature. Gene expression analysis has been applied to synovial tissue to define molecularly distinct forms of RA; however, expression analysis of tissue taken from a synovial joint is invasive and clinically impractical. Recent studies have demonstrated that unique gene expression changes can be identified in peripheral blood mononuclear cells (PBMCs) from patients with cancer, multiple sclerosis, and lupus. To identify RA disease-related genes, we performed a global gene expression analysis. RNA from PBMCs of 9 RA patients and 13 normal volunteers was analyzed on an oligonucleotide array. Compared with normal PBMCs, 330 transcripts were differentially expressed in RA. The differentially regulated genes belong to diverse functional classes and include genes involved in calcium binding, chaperones, cytokines, transcription, translation, signal transduction, extracellular matrix, integral to plasma membrane, integral to intracellular membrane, mitochondrial, ribosomal, structural, enzymes, and proteases. A k-nearest neighbor analysis identified 29 transcripts that were preferentially expressed in RA. Ten genes with increased expression in RA PBMCs compared with controls mapped to a RA susceptibility locus, 6p21.3. These results suggest that analysis of RA PBMCs at the molecular level may provide a set of candidate genes that could yield an easily accessible gene signature to aid in early diagnosis and treatment.

Gene expression profiling and correlation with outcome in clinical trials of the proteasome inhibitor bortezomib

The aims of this study were to assess the feasibility of prospective pharmacogenomics research in multicenter international clinical trials of bortezomib in multiple myeloma and to develop predictive classifiers of response and survival with bortezomib. Patients with relapsed myeloma enrolled in phase 2 and phase 3 clinical trials of bortezomib and consented to genomic analyses of pretreatment tumor samples. Bone marrow aspirates were subject to a negative-selection procedure to enrich for tumor cells, and these samples were used for gene expression profiling using DNA microarrays. Data quality and correlations with trial outcomes were assessed by multiple groups. Gene expression in this dataset was consistent with data published from a single-center study of newly diagnosed multiple myeloma. Response and survival classifiers were developed and shown to be significantly associated with outcome via testing on independent data. The survival classifier improved on the risk stratification provided by the International Staging System. Predictive models and biologic correlates of response show some specificity for bortezomib rather than dexamethasone. Informative gene expression data and genomic classifiers that predict clinical outcome can be derived from prospective clinical trials of new anticancer agents.

A single administration of recombinant human interleukin-12 is associated with increased expression levels of interferon-gamma and signal transducer and activator of transcription in healthy subjects

The objectives of this study were to assess the safety and tolerability of single doses of 1, 4, and 8 mug of recombinant human interleukin-12 (rhIL-12) administered subcutaneously to healthy subjects. The pharmacokinetics, pharmacodynamics, and pharmacogenomics of rhIL-12 were evaluated. Recombinant human IL-12 was well tolerated in these healthy male and female subjects. The most frequently reported adverse events were flu-like symptoms, which exhibited a dose-response relationship. Pharmacokinetic analysis suggested that serum IL-12 levels increased with dose. Analysis of serum levels indicated that interferon-gamma increased with the dose of rhIL-12, whereas IL-6 levels showed no changes with rhIL-12 treatment. The messenger ribonucleic acid expression of signal transducer and activator of transcription was significantly increased 24 hours after the administration of rhIL-12 for all dose groups versus placebo, and results indicated that the magnitude of increase may be dose dependent. This study suggests that interferon-gamma and signal transducer and activator of transcription are biomarkers of rhIL-12 activity.

Exploiting genotypic differences to identify genes important for EAE development

Experimental autoimmune encephalomyelitis (EAE) is an animal model of the human autoimmune disease multiple sclerosis (MS) and is primarily driven by T helper type 1 (Th1) cells. Interleukin (IL)-12 and interferon (IFN)-gamma are important cytokines involved in the differentiation and amplification of Th1 cells, however mice deficient in either IFN-gamma or IL-12 still develop EAE. We have used microarray analysis of EAE-affected CNS tissues in wild-type, IFN-gamma -/- and IL-12 -/- animals to identify genes critical for development of EAE. Over 500 genes were regulated in at least one genotype and over 94 genes were regulated in all three. Of those, 17 were also upregulated in spleen during the disease. We show that a majority of the genes regulated in EAE are also regulated in diseased regions of human MS tissues. The genes in the pool of 94 are more likely to be found regulated in MS patients than the genes regulated in only one or two of the mouse strains suggesting that analyzing gene expression under these multiple genetic conditions may lead to better identification of the genes critical for disease development.

The therapeutic utility of Interleukin-11 in the treatment of inflammatory disease

Interleukin-11 (IL-11) is a pleiotropic cytokine that exhibits anti-inflammatory and mucosal protective effects in a variety of animal models of acute and chronic inflammation, such as mucositis, inflammatory bowel disease and autoimmune joint disease. This reduction in inflammation and epithelial damage is mediated in part through effects of recombinant human (rh) IL-11 on macrophage effector function and epithelial cell growth. In vitro studies indicate that rhIL-11 inhibits tumour necrosis factor (TNF)-alpha, IL-1beta, IL-12, IL-6, and nitric oxide production from activated macrophages. Analysis of the effects of rhIL-11 on transcription factors that activate pro-inflammatory cytokines demonstrate that the level of induced nuclear factor kappa B (NF-kappaB) binding activity in the nucleus of rhIL-11-treated peritoneal macrophages is significantly reduced. Studies of normal intestinal epithelial cells indicate that rhIL-11 reduces the rate of cellular proliferation. Analysis of cell-cycle progression demonstrates that growth inhibition of epithelial cells by rhIL-11 correlates with delayed entry into S phase and suppression of pRB phosphorylation. IL-11 also protects intestinal crypt stem cells from radiation- or chemotherapy-induced insults. Such immunomodulatory and epithelial activities may contribute to the protective effects of this cytokine and support the clinical utility of rhIL-11 in the treatment of mucositis, as well as a variety of chronic inflammatory diseases, such as Crohn's disease and rheumatoid arthritis.

Clinical pharmacogenomics and transcriptional profiling in early phase oncology clinical trials

Microarray-based expression profiling studies in the field of oncology have demonstrated encouraging correlations between tumor transcriptional profiles and eventual patient outcomes. These findings have fueled great interest in the application of transcriptional profiling to samples available from real-time clinical trials, and clinical pharmacogenomic objectives utilizing transcriptional profiling strategies are becoming increasingly incorporated into clinical trial study designs. Over the last few years several retrospective studies based on the profiling of archival tumor tissues suggest that transcriptional analysis of oncology samples may provide general prognosis measures, and in some cases may even predict response to specific therapies. Recently the FDA released a voluntary genomic data guidance meant to assist both regulatory agencies and pharmaceutical companies alike in evaluating the potential benefit of implementing expression profiling studies during the preclinical and clinical phases of drug development. Despite the great promise afforded by this technology, the ultimate benefit of applying transcriptional profiling in prospective clinical trials has yet to be realized because a number of practical impediments to this process exist. The multi-fold purpose of the current review is to highlight the increasing evidence from studies that have identified transcriptional signatures in archived tumors prognostic of patient outcome, to describe some of the drivers for the implementation of transcriptional profiling strategies in real-time drug development, to discuss the use of transcriptional profiling in the context of increasingly complex translational medicine strategies, and to highlight the practical issues and potential approaches involved in the successful application of clinical pharmacogenomic objectives during real-time clinical trials. Strategic implementation of transcriptional profiling in early oncology clinical trials can provide an opportunity to identify predictive markers of clinical response and eventually provide a substantial step forward towards the era of personalized medicine.

Transcriptional profiles in peripheral blood mononuclear cells prognostic of clinical outcomes in patients with advanced renal cell carcinoma

PURPOSE

Given their accessibility, surrogate tissues, such as peripheral blood mononuclear cells (PBMC), may provide potential predictive biomarkers in clinical pharmacogenomic studies. In leukemias and lymphomas, the prognostic value of peripheral blast expression profiles is clear; however, it is unclear whether circulating mononuclear cells of patients with solid tumors might yield profiles with similar prognostic associations.

EXPERIMENTAL DESIGN

In this study, we evaluated the association of expression profiles in PBMCs with clinical outcomes in patients with advanced renal cell cancer. Transcriptional patterns in PBMCs of 45 renal cell cancer patients were compared with clinical outcome data at the conclusion of a phase II study of the mTOR kinase inhibitor CCI-779 to determine whether pretreatment transcriptional patterns in PBMCs were correlated with eventual patient outcomes.

RESULTS

Unsupervised hierarchical clustering of the PBMC profiles using all expressed genes identified clusters of patients with significant differences in survival. Cox proportional hazards modeling showed that the expression levels of many PBMC transcripts were predictors for the patient outcomes of time to progression and overall survival (time to death). Supervised class prediction approaches identified multivariate expression patterns in PBMCs capable of assigning favorable outcomes of time to death and time to progression in a test set of renal cancer patients, with overall performance accuracies of 72% and 85%, respectively.

CONCLUSIONS

The present study provides the first example of gene expression profiling in peripheral blood, a clinically accessible surrogate tissue, for identifying patterns of gene expression associated with higher likelihoods of positive outcome in patients with a solid tumor.

Transcriptional Profiles in Peripheral Blood Mononuclear Cells Prognostic of Clinical Outcomes in Patients with Advanced Renal Cell Carcinoma

Purpose: Given their accessibility, surrogate tissues, such as peripheral blood mononuclear cells (PBMC), may provide potential predictive biomarkers in clinical pharmacogenomic studies. In leukemias and lymphomas, the prognostic value of peripheral blast expression profiles is clear; however, it is unclear whether circulating mononuclear cells of patients with solid tumors might yield profiles with similar prognostic associations.

Experimental Design: In this study, we evaluated the association of expression profiles in PBMCs with clinical outcomes in patients with advanced renal cell cancer. Transcriptional patterns in PBMCs of 45 renal cell cancer patients were compared with clinical outcome data at the conclusion of a phase II study of the mTOR kinase inhibitor CCI-779 to determine whether pretreatment transcriptional patterns in PBMCs were correlated with eventual patient outcomes.

Results: Unsupervised hierarchical clustering of the PBMC profiles using all expressed genes identified clusters of patients with significant differences in survival. Cox proportional hazards modeling showed that the expression levels of many PBMC transcripts were predictors for the patient outcomes of time to progression and overall survival (time to death). Supervised class prediction approaches identified multivariate expression patterns in PBMCs capable of assigning favorable outcomes of time to death and time to progression in a test set of renal cancer patients, with overall performance accuracies of 72% and 85%, respectively.

Conclusions: The present study provides the first example of gene expression profiling in peripheral blood, a clinically accessible surrogate tissue, for identifying patterns of gene expression associated with higher likelihoods of positive outcome in patients with a solid tumor.

Increased expression of interleukin 23 p19 and p40 in lesional skin of patients with psoriasis vulgaris

Psoriasis is a type I–deviated disease characterized by the presence of interferon (IFN)-γ and multiple IFN-related inflammatory genes in lesions. Because interleukin (IL)-23 is now recognized to play a role in the recruitment of inflammatory cells in a T helper cell (Th)1-mediated disease, we examined psoriasis skin lesions for production of this newly described cytokine. IL-23 is composed of two subunits: a unique p19 subunit and a p40 subunit shared with IL-12. We found a reliable increase in p19 mRNA by quantitative reverse transcription polymerase chain reaction in lesional skin compared with nonlesional skin (22.3-fold increase; P = 0.001). The p40 subunit, shared by IL-12 and IL-23, increased by 11.6-fold compared with nonlesional skin (P = 0.003), but the IL-12 p35 subunit was not increased in lesional skin. IL-23 was expressed mainly by dermal cells and increased p40 immunoreactivity was visualized in large dermal cells in the lesions. Cell isolation experiments from psoriatic tissue showed strong expression of p19 mRNA in cells expressing monocyte (CD14⁺ CD11c⁺ CD83⁻) and mature dendritic cell (DC) markers (CD14⁻ CD11c⁺ CD83⁺), whereas in culture, the mRNAs for p40 and p19 were strongly up-regulated in stimulated monocytes and monocyte-derived DCs, persisting in the latter for much longer periods than IL-12. Our data suggest that IL-23 is playing a more dominant role than IL-12 in psoriasis, a Th1 type of human inflammatory disease.

Interleukin-11 inhibits NF-kappaB and AP-1 activation in islets and prevents diabetes induced with streptozotocin in mice

This laboratory has reported that multiple low doses of streptozotocin (MLD-STZ) similarly upregulate the T helper (Th)1-type proinflammatory cytokines tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma in islets of both the diabetes-susceptible male and the diabetes-resistant female C57BL/6 mice and that MLD-STZ downregulates the anti-inflammatory Th2-type cytokines interleukin (IL)-4 and IL-10, as well as the anti-inflammatory Th3-type cytokine-transforming growth factor (TGF)-ss1 in islets of male, but not female, mice. Thus, diabetes is associated with a relative preponderance of local proinflammatory cytokines. Here, we investigated the effects of MLD-STZ on the anti-inflammatory cytokine IL-11 and the transcription factors nuclear factor (NF)-kappaB and activator protein (AP)-1, which are involved in gene activation of proinflammatory cytokines, and on the cytosolic kinase (IKK-alpha) of NF-kappaB inhibitor (IkappaB). Furthermore, the effect of recombinant human (rh)IL-11 on MLD-STZ diabetes, insulitis, cytokines, IKK-alpha, NF-kappaB, and AP-1 was analyzed in islets. Interleukin-11 prevented diabetes without affecting insulitis; attenuated TNF-alpha and IFN-gamma response; and stimulated IL-4 production and inhibited activation of IKK-alpha, NF-kappaB, and AP-1. The results demonstrated the potential of rhIL-11 in preventing MLD-STZ diabetes through enhancement of anti-inflammatory responses in islets. In this process, the transcription factors NF-kappaB and AP-1 might play a key role.

Disease-associated expression profiles in peripheral blood mononuclear cells from patients with advanced renal cell carcinoma

Expression profiling has demonstrated that transcriptomes of primary malignancies differ from those in normal tissue. It is unknown, however, whether there exist "surrogate" transcriptional markers in peripheral blood mononuclear cells (PBMCs) of patients with solid tumors. We identified transcripts expressed differentially between PBMCs from renal cell carcinoma patients and normal subjects, some of which appear to reflect specific immune responses of circulating cells. We also identified small sets of predictor genes distinguishing PBMCs from renal cell carcinoma patients and normal volunteers with high accuracy. The present findings have important implications for diagnosis and future clinical pharmacogenomic studies of antitumor therapies.

Narrowband (312-nm) UV-B suppresses interferon gamma and interleukin (IL) 12 and increases IL-4 transcripts: differential regulation of cytokines at the single-cell level

OBJECTIVE

To determine whether 312-nm UV-B alters production of effector and regulatory cytokines by viable T cells that remain in psoriatic lesions during UV-B phototherapy.

DESIGN

Prospective study.

SETTING

General clinical research center of The Rockefeller University Hospital.

PATIENTS

Ten adult patients with moderate to severe psoriasis vulgaris that was difficult to manage were sequentially enrolled in our protocols, and biopsies were taken at various time points from resolving lesions.

INTERVENTION

Narrowband (312-nm) UV-B was given starting at 50% of a minimum erythema dose, then increased daily 10% to 15% if no apparent erythema was induced. Patients continued with treatment until maximal benefit was noted. In some experiments, T cells were irradiated ex vivo with standard TL-01 fluorescent bulbs (Philips Lighting Co, Somerset, NJ).

MAIN OUTCOME MEASURES

Intracellular cytokine staining was done using flow cytometry to quantify numbers of cytokine-producing cells from epidermal and peripheral T cells. The production of messenger RNA for interleukin (IL) 12, interferon (IFN) gamma, tumor necrosis factor alpha, IL-4, and IL-10 was measured by quantitative reverse transcription-polymerase chain reaction.

RESULTS

Ultraviolet-B treatment eliminated production of IL-12 messenger RNA and decreased production of IFN-gamma messenger RNA by more than 60% in irradiated psoriasis lesions (P<.03 for both). Within 1 to 2 weeks of starting UV-B treatment, the frequency of viable T cells producing IFN-gamma decreased 40% to 65%. In contrast, mRNA for IL-4 increased by 82% (P =.05) during UV-B treatment, and the number of IL-4-producing cells increased by 228% after 1 week of treatment. In vitro experiments established that, on the single-cell level, survival and cytokine production by type 1 T cells were differentially regulated by UV-B.

CONCLUSIONS

Therapeutic UV-B suppresses the type 1 (proinflammatory) axis as defined by IL-12, IFN-gamma, and IL-8, and can selectively reduce proinflammatory cytokine production by individual T cells. Knowledge of the immunomodulatory effects of UV-B will help to integrate this modality in future therapeutics for psoriasis based on deliberate blockade of inflammatory molecular pathways in the type 1 T-cell pathway.

Molecular classification of psoriasis disease-associated genes through pharmacogenomic expression profiling

Psoriasis is recognized as the most common T cell-mediated inflammatory disease in humans. Genetic linkage to as many as six distinct disease loci has been established but the molecular etiology and genetics remain unknown. To begin to identify psoriasis disease-related genes and construct in vivo pathways of the inflammatory process, a genome-wide expression screen of multiple psoriasis patients was undertaken. A comprehensive list of 159 genes that define psoriasis in molecular terms was generated; numerous genes in this set mapped to six different disease-associated loci. To further interpret the functional role of this gene set in the disease process, a longitudinal pharmacogenomic study was initiated to understand how expression levels of these transcripts are altered following patient treatment with therapeutic agents that antagonize calcineurin or NF-KB pathways. Transcript levels for a subset of these 159 genes changed significantly in those patients who responded to therapy and many of the changes preceded clinical improvement. The disease-related gene map provides new insights into the pathogenesis of psoriasis, wound healing and cellular-immune reactions occurring in human skin as well as other T cell-mediated autoimmune diseases. In addition, it provides a set of candidate genes that may serve as novel therapeutic intervention points as well as surrogate and predictive markers of treatment outcome.

Protective effect of rhIL-11 in a murine model of acetaminophen-induced hepatotoxicity

Acetaminophen intoxication results in hepatotoxicity associated with increased serum concentrations of hepatocellular leakage enzymes such as aspartate aminotransferase, lactate dehydrogenase, and alanine aminotransferase, centrilobular degeneration and necrosis, and activation of Kupffer cells. Recombinant human Interleukin-11 (rhIL-11) downregulates the production of proinflammatory mediators from activated macrophages and has direct effects on hepatocyte gene expression. Based on these biological activities of rhIL-11, the effect of pretreatment with rhIL-11 in a murine model of acetaminophen-induced hepatotoxicity was examined. Administration of 500 microg/kg acetaminophen to B6C3F1 mice resulted in progressive hepatotoxicity as demonstrated by elevated serum concentrations of hepatocellular leakage enzymes and TNFalpha and histopathology. Pretreatment with 250 or 500 microg/kg of subcutaneously administered rhIL-11 2 hours before acetaminophen administration reduced serum concentrations of hepatocellular leakage enzymes and TNFalpha by 40-50%. This was associated with a statistically significant decrease in mean severity score for centrilobular hemorrhage and necrosis from grade 3 to grade 2 for rhIL-11-treated animals compared to vehicle. These results indicate that treatment with rhIL-11 has a protective effect in a model of acetaminophen-induced liver damage.

Interleukin-11 modulates Th1/Th2 cytokine production from activated CD4+ T cells

Recombinant human interleukin-11 (rHuIL-11) is a pleiotropic cytokine with effects on multiple cell types. rHuIL-11 reduces activated macrophage activity and downregulates production of proinflammatory mediators, such as tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO). In vitro and in vivo, rHuIL-11 inhibits production of key immunostimulatory cytokines, including IL-12 and interferon-gamma (IFN-gamma). rHuIL-11 has recently demonstrated immunomodulatory activity to downregulate IFN-gamma production, increase IL-4 production, and reduce inflammatory tissue injury in a human psoriasis clinical trial. The cellular mechanisms of these effects are not fully elucidated. We demonstrate here that expression of gp130 and IL-11 receptor (IL-11R) alpha mRNA, components of the IL-11R complex, are detected in human and murine CD4(+) and CD8(+) lymphocytes, suggesting that rHuIL-11 can directly interact with T cells. In a cell culture model of murine T cell differentiation, rHuIL-11 acts to inhibit IL-2 production as well as IL-12-induced IFN-gamma production and enhances IL-4 and IL-10 production. rHuIL-11 had no effect on T cell proliferation. The ability of rHuIL-11 to modulate cytokine production from activated CD4(+) T cells provides a mechanism through which rHuIL-11 may ameliorate such inflammatory diseases as psoriasis.

Interleukin-11 therapy selectively downregulates type I cytokine proinflammatory pathways in psoriasis lesions

Psoriasis is a chronic inflammatory skin disease in which epidermal hyperplasia results from skin infiltration by type I T lymphocytes and release of associated cytokines. A multifunctional cytokine, rhIL-11, modulates macrophage and type I T-lymphocyte function in cell culture and shows anti-inflammatory activity in animal models. We are testing subcutaneous delivery of rhIL-11 to patients with psoriasis in a phase 1 open-label dose-escalation clinical trial. Tissue was obtained from lesional and uninvolved skin before and during treatment with rhIL-11 and was examined by histology/immunohistochemistry and quantitative RT-PCR. Expression of over 35 genes was examined in all patients, and multiple genetic markers of psoriasis were identified. Expression of numerous proinflammatory genes was elevated in psoriatic tissue compared with nonlesional skin. Seven of 12 patients responded well to rhIL-11 treatment. Amelioration of disease by rhIL-11, as shown by reduced keratinocyte proliferation and cutaneous inflammation, was associated with decreased expression of products of disease-related genes, including K16, iNOS, IFN-gamma, IL-8, IL-12, TNF-alpha, IL-1beta, and CD8, and with increased expression of endogenous IL-11. We believe that this is the first study in humans to indicate that type I cytokines can be selectively suppressed by an exogenous immune-modifying therapy. The study highlights the utility of pharmacogenomic monitoring to track patient responsiveness and to elucidate anti-inflammatory mechanisms.

Interleukin-11 reduces T-cell-dependent experimental liver injury in mice

Recombinant human interleukin-11 (rhIL-11) is a multifunctional cytokine that can reduce inflammation through the downregulation of multiple pro-inflammatory mediators from activated macrophages. rhIL-11 also inhibits production of several immunostimulatory cytokines such as IL-12 and interferon gamma (IFN-gamma) and has shown biological activity in multiple animal models of inflammatory disease consistent with immunomodulatory effects on macrophages and T cells. To further elucidate the anti-inflammatory activity of rhIL-11 in vivo, the effect of rhIL-11 in a model of Concanavalin A (Con-A)-induced T-cell-mediated hepatotoxicity was examined. Administration of a single dose of rhIL-11 before Con-A administration reduced centrilobular liver necrosis and enhanced survival. A dose-dependent reduction in serum levels of liver enzymes, tumor necrosis factor alpha (TNF-alpha), and IFN-gamma corresponded with this amelioration of liver damage. No significant change in infiltrating lymphocyte populations in the liver was observed following rhIL-11 treatment. Taken together, these results indicate that rhIL-11 ameliorates T-cell-mediated hepatic injury and suggests its therapeutic potential to treat inflammatory liver disease.

Autocrine Regulation of IL-12 Receptor Expression Is Independent of Secondary IFN-γ Secretion and not Restricted to T and NK Cells

The biological response to IL-12 is mediated through specific binding to a high affinity receptor complex composed of at least two subunits (designated IL-12Rβ1 and IL-12Rβ2) that are expressed on NK cells and activated T cells. The selective loss of IL-12Rβ2 expression during Th2 T cell differentiation suggests that regulation of this receptor component may govern IL-12 responsiveness. In murine assays, down-regulation of IL-12Rβ2 expression can be prevented by treatment with IFN-γ, indicating that receptor expression and hence IL-12 responsiveness may be regulated, at least in part, by the local cytokine milieu. In this study, we report that cellular expression of both IL-12Rβ1 and β2 mRNA is increased in the lymph nodes of naive mice following systemic administration of murine rIL-12 (rmIL-12). Changes in IL-12R mRNA were associated with increased IFN-γ secretion following ex vivo activation of lymph node cells with rmIL-12, indicating the presence of a functional receptor complex. Expression of IL-12R mRNA was not restricted to lymph node T cells, and its autocrine regulation was independent of secondary IFN-γ secretion. Data from fractionated lymph node cells as well as rmIL-12-treated B cell-deficient mice suggest that IL-12-responsive B cells may represent an alternative cellular source for IFN-γ production. However, the strength of the biological response to rmIL-12 is not governed solely by receptor expression, as rmIL-12-induced IFN-γ secretion from cultured lymph node cells is accessory cell dependent and can be partially blocked by inhibition of B7 costimulation.

Autocrine regulation of IL-12 receptor expression is independent of secondary IFN-gamma secretion and not restricted to T and NK cells

The biological response to IL-12 is mediated through specific binding to a high affinity receptor complex composed of at least two subunits (designated IL-12Rbeta1 and IL-12Rbeta2) that are expressed on NK cells and activated T cells. The selective loss of IL-12Rbeta2 expression during Th2 T cell differentiation suggests that regulation of this receptor component may govern IL-12 responsiveness. In murine assays, down-regulation of IL-12Rbeta2 expression can be prevented by treatment with IFN-gamma, indicating that receptor expression and hence IL-12 responsiveness may be regulated, at least in part, by the local cytokine milieu. In this study, we report that cellular expression of both IL-12Rbeta1 and beta2 mRNA is increased in the lymph nodes of naive mice following systemic administration of murine rIL-12 (rmIL-12). Changes in IL-12R mRNA were associated with increased IFN-gamma secretion following ex vivo activation of lymph node cells with rmIL-12, indicating the presence of a functional receptor complex. Expression of IL-12R mRNA was not restricted to lymph node T cells, and its autocrine regulation was independent of secondary IFN-gamma secretion. Data from fractionated lymph node cells as well as rmIL-12-treated B cell-deficient mice suggest that IL-12-responsive B cells may represent an alternative cellular source for IFN-gamma production. However, the strength of the biological response to rmIL-12 is not governed solely by receptor expression, as rmIL-12-induced IFN-gamma secretion from cultured lymph node cells is accessory cell dependent and can be partially blocked by inhibition of B7 costimulation.

Hematopoietic, immunomodulatory and epithelial effects of interleukin-11

Interleukin 11 (IL-11) is a pleiotropic cytokine with biological activities on many different cell types. Recombinant human IL-11 (rhIL-11) is produced by recombinant DNA technology in Escherichia coli. Both in vitro and in vivo, rhIL-11 has shown effects on multiple hematopoietic cell types. Its predominant in vivo hematopoietic activity is the stimulation of peripheral platelet counts in both normal and myelosuppressed animals. This activity is mediated through effects on both early and late progenitor cells to stimulate megakaryocyte differentiation and maturation. rhIL-11 has been approved for the treatment of chemotherapy-induced thrombocytopenia. The hematopoietic effects of rhIL-11 are most likely direct effects on progenitor cells and megakaryocytes in combination with other cytokines or growth factors. rhIL-11 also induces secretion of acute phase proteins (ferritin, haptoglobin, C-reactive protein, and fibrinogen) from the liver. The induction of heme oxidase and inhibition of several P450 oxidases have been reported from in vitro studies. In vivo, rhIL-11 treatment decreases sodium excretion by the kidney by an unknown mechanism and induces hemodilution. rhIL-11 also exhibits anti-inflammatory effects in a variety of animal models of acute and chronic inflammation, including inflammatory bowel disease, inflammatory skin disease, autoimmune joint disease, and various infection-endotoxemia syndromes. rhIL-11 has trophic effects on non-transformed intestinal epithelium under conditions of mucosal damage. The mechanism of the anti-inflammatory activity of rhIL-11 has been extensively studied. rhIL-11 directly affects macrophage and T cell effector function. rhIL-11 inhibits tumor necrosis factor-alpha (TNF alpha), interleukin 1beta (IL-1beta), interleukin 12 (IL-12), interleukin 6 (IL-6), and nitric oxide (NO) production from activated macrophages in vitro. The inhibition of cytokine production was associated with inhibition of nuclear translocation of the transcription factor, nuclear factor kappa B (NF-kappaB). The block to NF-kappaB nuclear translocation correlates with the ability of rhIL-11 to maintain or enhance production of the inhibitors of NF-kappaB, IkappaB-alpha and IkappaB-beta. In addition to effects on macrophages, rhIL-11 also reduces CD4+ T cell production of Th1 cytokines, such as IFN gamma induced by IL-12, while enhancing Th2 cytokine production. rhIL-11 also blocks IFN gamma production in vivo. The molecular effects of rhIL-11 have also been studied in a clinical trial. Molecular analysis of skin biopsies of patients with psoriasis before and during rhIL-11 treatment demonstrates a decrease in mRNA levels of TNF alpha, IFN gamma and iNOS. These activities suggest that in addition to its thrombopoietic clinical use, rhIL-11 may also be valuable in the treatment of inflammatory diseases. The clinical utility of the anti-inflammatory properties of rhIL-11 is being investigated in patients with Crohn's disease, psoriasis and rheumatoid arthritis. These diseases are believed to be initiated and maintained by activated CD4+ Th1 cells in conjunction with activated macrophages.

Recombinant human interleukin-11 does not affect functions of purified human neutrophils in vitro

Recombinant human interleukin-11 (rHu-IL-11) is a multifunctional cytokine with thrombopoietic activity and demonstrated clinical efficacy in treating chemotherapy-induced thrombocytopenia. rHu-IL-11 also exhibits anti-inflammatory activity and is currently in clinical trials for the treatment of several inflammatory diseases. As neutrophils are involved in both innate immunity and an acute inflammatory response, the effect of rHU-IL-11 on the function of human peripheral blood neutrophils in vitro was examined. rHu-IL-11 was not cytotoxic and did not induce superoxide anion production or the release of granular enzymes from resting neutrophils. Phagocytosis and chemotaxis were unaffected. rHu-IL-11 treatment did not block the response of neutrophils to stimulation. Pretreatment with rHu-IL-11 did not reduce production of IL-8 following activation with lipopolysaccharide (LPS) or zymosan A particles. Pretreatment with rHu-IL-11 did not affect the release of lysozyme and beta-glucuronidase in response to A23187 or PMA-stimulated production of superoxide anion. These results indicate that rHu-IL-11 does not directly modulate key functions of neutrophils in vitro.

Interleukin-11. A gp130 cytokine

Interleukin (IL)-11 is a member of the gp130 family of cytokines. Comparison of IL-11 with another gp130 family member, IL-6, indicates that these two cytokines share many overlapping signal transduction mechanisms. However, unlike IL-6, treatment of patients with a recombinant human form of IL-11 (rhIL-11) does not increase body temperature, suggesting significant differences in the in vivo function of these two molecules. Recent studies demonstrate that IL-11 has potent anti-inflammatory activity in a variety of preclinical animal models of disease. rhIL-11 reduces production of proinflammatory mediators such as tumor necrosis factor-alpha and IL-12 from activated macrophages. This effect on proinflammatory cytokine production is mediated at the transcriptional level by inhibition of the transcription factor, NF- kappa B. To further understand the anti-inflammatory mechanisms of action of rhIL-11 and to elucidate differences between IL-11 and IL-6 signal transduction pathways, the effects of these two cytokines on in vitro macrophage function were compared.

IL-11 regulates macrophage effector function through the inhibition of nuclear factor-kappaB

Recombinant human IL-11 (rhIL-11) is an anti-inflammatory cytokine that can reduce the production of inflammatory mediators such as TNF-alpha, IL-1beta, IL-12, IL-6, and nitric oxide. Inhibition of proinflammatory cytokine production from activated macrophages was associated with a reduction in the levels of LPS-induced TNF-alpha, IL-1beta, IL-6, and IL-12 p40 mRNA. Analysis of rhIL-11 effects on transcription factors that activate proinflammatory cytokines demonstrated that the level of LPS-induced NF-kappaB binding activity in the nucleus of rhIL-11-treated peritoneal macrophages was significantly reduced. The block to NF-kappaB nuclear translocation correlated with the ability of rhIL-11 to maintain or increase protein levels of the inhibitors of NF-kappaB, IkappaB-alpha, and IkappaB-beta following LPS treatment. Furthermore, rhIL-11-treatment of LPS macrophages resulted in significant elevation of IkappaB-alpha and IkappaB-beta mRNA levels. These results suggest that the anti-inflammatory activity of rhIL-11 is mediated in part by inhibition of NF-kappaB-dependent transcriptional activation. Furthermore, these studies demonstrate for the first time the regulation of IkappaB-beta by an anti-inflammatory cytokine. Given the finding that inappropriate activation of NF-kappaB contributes to multiple inflammatory conditions, the ability of rhIL-11 to inhibit the binding activity of this pleiotropic transcription factor indicates that rhIL-11 has therapeutic potential in a wide range of diseases.

IL-11 regulates macrophage effector function through the inhibition of nuclear factor-kappaB

Recombinant human IL-11 (rhIL-11) is an anti-inflammatory cytokine that can reduce the production of inflammatory mediators such as TNF-alpha, IL-1beta, IL-12, IL-6, and nitric oxide. Inhibition of proinflammatory cytokine production from activated macrophages was associated with a reduction in the levels of LPS-induced TNF-alpha, IL-1beta, IL-6, and IL-12 p40 mRNA. Analysis of rhIL-11 effects on transcription factors that activate proinflammatory cytokines demonstrated that the level of LPS-induced NF-kappaB binding activity in the nucleus of rhIL-11-treated peritoneal macrophages was significantly reduced. The block to NF-kappaB nuclear translocation correlated with the ability of rhIL-11 to maintain or increase protein levels of the inhibitors of NF-kappaB, IkappaB-alpha, and IkappaB-beta following LPS treatment. Furthermore, rhIL-11-treatment of LPS macrophages resulted in significant elevation of IkappaB-alpha and IkappaB-beta mRNA levels. These results suggest that the anti-inflammatory activity of rhIL-11 is mediated in part by inhibition of NF-kappaB-dependent transcriptional activation. Furthermore, these studies demonstrate for the first time the regulation of IkappaB-beta by an anti-inflammatory cytokine. Given the finding that inappropriate activation of NF-kappaB contributes to multiple inflammatory conditions, the ability of rhIL-11 to inhibit the binding activity of this pleiotropic transcription factor indicates that rhIL-11 has therapeutic potential in a wide range of diseases.

Recombinant human IL-11 attenuates the inflammatory response through down-regulation of proinflammatory cytokine release and nitric oxide production

To elucidate the molecular mechanisms regulating the anti-inflammatory activities of recombinant human (rh)IL-11, the ability of rhIL-11 to reduce serum levels of inflammatory mediators such as TNF-alpha, IL-1beta, IL-12, and IFN-gamma in LPS-treated mice and to down-regulate macrophage function in culture was investigated. In a mouse model of endotoxemia, pretreatment with rhIL-11 blocked LPS-induced elevation of TNF-alpha, IL-1beta, and IFN-gamma serum levels, but had no effect on IL-12 p40, IL-6, or IL-10 serum levels. The effects of rhIL-11 on the production of inflammatory mediators in vivo may occur in part through direct interactions with macrophages. rhIL-11 pretreatment of thioglycollate-elicited peritoneal macrophages resulted in greater than 60% inhibition of LPS-induced production of TNF-alpha, IL-1beta, IL-12 p40, and nitric oxide. The activity of rhIL-11 was not mediated through induction of IL-10, IL-6, or TGF-beta1. These results indicate that the ability of rhIL-11 to modulate the inflammatory response is not dependent on known anti-inflammatory cytokines and substantiate a role for this cytokine in the attenuation of inflammatory conditions.

Recombinant human IL-11 attenuates the inflammatory response through down-regulation of proinflammatory cytokine release and nitric oxide production

To elucidate the molecular mechanisms regulating the anti-inflammatory activities of recombinant human (rh)IL-11, the ability of rhIL-11 to reduce serum levels of inflammatory mediators such as TNF-alpha, IL-1beta, IL-12, and IFN-gamma in LPS-treated mice and to down-regulate macrophage function in culture was investigated. In a mouse model of endotoxemia, pretreatment with rhIL-11 blocked LPS-induced elevation of TNF-alpha, IL-1beta, and IFN-gamma serum levels, but had no effect on IL-12 p40, IL-6, or IL-10 serum levels. The effects of rhIL-11 on the production of inflammatory mediators in vivo may occur in part through direct interactions with macrophages. rhIL-11 pretreatment of thioglycollate-elicited peritoneal macrophages resulted in greater than 60% inhibition of LPS-induced production of TNF-alpha, IL-1beta, IL-12 p40, and nitric oxide. The activity of rhIL-11 was not mediated through induction of IL-10, IL-6, or TGF-beta1. These results indicate that the ability of rhIL-11 to modulate the inflammatory response is not dependent on known anti-inflammatory cytokines and substantiate a role for this cytokine in the attenuation of inflammatory conditions.

A novel developmental regulatory motif required for stage-specific activation of the epsilon-globin gene and nuclear factor binding in embryonic erythroid cells

Members of the human beta-globin gene family are expressed at discrete stages of development and therefore provide an important model system for examining mechanisms of temporal gene regulation. We have previously shown that expression of the embryonic beta-like globin gene (epsilon) is mediated by a complex array of positive and negative upstream control elements. Correct developmental stage- and tissue-specific gene expression is conferred by synergistic interactions between a positive regulatory element (termed epsilon-PRE II) which is active only in embryonic erythroid cells and at least two other regulatory domains upstream of the epsilon-globin gene promoter. A nuclear factor highly enriched in cultured embryonic erythroid cells and in mouse embryonic yolk sac binds to a novel, evolutionarily conserved sequence within epsilon-PRE II. We show here that binding of this factor to the conserved element within epsilon-PRE II is critical for transcriptional activity. Point mutations that interfere with protein binding to epsilon-PRE II abolish transcriptional activation of the constitutive epsilon-globin promoter. Adult erythroid nuclei (from cultured cells or adult mouse liver) also contain a factor that binds to this region, but the complex formed migrates more rapidly during nondenaturing electrophoresis, suggesting either that distinct proteins bind to epsilon-PRE II or that a single protein is differentially modified in these cells in a way that modulates its activity. Several lines of evidence suggest that the binding factors in embryonic and adult erythroid cells are distinguished by posttranscriptional differences.

Upstream regulatory region of the human embryonic beta-like globin gene, epsilon

The sequence of the human embryonic beta-like globin gene (epsilon) upstream regulatory region has been reported previously. In the course of our own work, we found a significant number of discrepancies between our sequence and the data base sequence, which we show here to contain large clusters of errors within functional epsilon-globin regulatory domains.

Developmental regulation of the human embryonic beta-like globin gene is mediated by synergistic interactions among multiple tissue- and stage-specific elements

The stage-specific regulation of mammalian embryonic globin genes has been an experimentally elusive problem, in part because of the developmentally early timing of their expression. We have carried out a systematic analysis of truncation and internal deletion mutations within the 5'-flanking region of the human embryonic beta-like globin gene (epsilon) in erythroid and nonerythroid cell lines. Within a 670-bp region upstream from the constitutive promoter are multiple positive and negative control elements. Of these, a positive regulatory element (epsilon-PRE II) which is active only in embryonic erythroid cells is of particular interest. Remarkably, although it is inactive on its own, in the presence of other sequences located further upstream, it confers tissue- and developmental stage-specific expression on a constitutive epsilon-globin or heterologous promoter. The activity of epsilon-PRE II is also modulated by another positive regulatory domain located further downstream to direct erythroid cell-specific, but little or no embryonic stage-specific, transcription. A nuclear factor highly enriched in embryonic erythroid cells binds specifically within a 19-bp region of epsilon-PRE II. Nuclei from adult erythroid cells also contain a factor that binds to this region but forms a complex of faster electrophoretic mobility. We speculate that interactions between epsilon-PRE II and other upstream control elements play an important role in the developmental regulation of the human embryonic beta-like globin gene.

IGH minisatellite suppression of USF-binding-site- and E mu-mediated transcriptional activation of the adenovirus major late promoter

The 50bp repeat unit of the minisatellite within the DH-JH interval of the human immunoglobulin heavy chain locus binds a nuclear factor present in a wide variety of cell types. The binding site contains the myc/HLH motif, CACGTG, and represents a 15 of 17 base match for the USF/MLTF binding site adjacent to the adenovirus major late promoter (MLP). Unlike the USF/MLTF site, the IGH minisatellite possesses no enhancer activity. However, it can significantly suppress, in cis and in trans, USF-site-mediated transcriptional activation of the MLP. In murine myeloma cells, the IGH minisatellite can suppress, in trans, MLP activation by the murine heavy chain gene enhancer, E mu. These activities potentially represent a DNA-based form of squelching.

Members of the rel/NF-kappa B family of transcriptional regulatory proteins bind the HRAS1 minisatellite DNA sequence

The 28 base pair repeat unit of a minisatellite 1000 bp downstream from the human HRAS1 gene (VTRHRAS1) bound four proteins (p45, p50, p72 and p85) in nuclear extracts from a variety of human cell lines which were indistinguishable from several members of the rel/NF-kappa B family of transcriptional regulatory factors. VTRHRAS1 bound the constitutively expressed, but not the inducible, forms of these proteins. Analysis of partially purified binding factors from different cell lines demonstrated qualitative differences in the p50 subunit; phosphocellulose fractionation also revealed considerable heterogeneity in the p72 and p85 subunits. These results suggest the possibility that the HRAS1 minisatellite, in serving as a tandem array of rel/NF-kappa B binding sites, may function in the transcriptional regulation of HRAS1 and nearby genes.