Type I interferon gene signature test-low and -high patients with systemic lupus erythematosus have distinct gene expression signatures.

OBJECTIVES: Type I interferon (IFN) is implicated in systemic lupus erythematosus (SLE) pathogenesis. We aimed to identify type I IFN signaling-dependent and -independent molecular pathways in a large population of patients with SLE. METHODS: Baseline blood samples from adult patients with moderate to severe SLE from two Phase IIb studies (NCT01438489, n = 265; NCT01283139, n = 416) were profiled using whole transcriptome array analyses. Type I IFN gene signature (IFNGS) test status (high or low) was determined using a validated qualitative polymerase chain reaction-based test. IFN-type-specific signatures were developed by stimulating healthy blood with IFN-ß, IFN-γ, IFN-λ, IFN-ω, or pooled IFN-α. These, and multiple literature-derived cell type and cytokine pathway signatures, were evaluated in individual and pooled study populations. A Fisher's exact test was used for associations, adjusted for false discovery rate. RESULTS: Whole blood samples from IFNGS test-high patients were enriched versus IFNGS test-low patients for CD40L signaling (Q < 0.001), CXC cytokine (Q < 0.001), TLR8-mediated monocyte activation (Q < 0.001), IgG (Q < 0.001), major histocompatibility complex class I (Q < 0.001), and plasma cell (Q < 0.001) gene expression signatures. IFNGS test-low patients had significant enrichment of eosinophil (Q < 0.001), IFN-γ-specific (Q = 0.005), and T-cell or B-cell (Q < 0.001) signatures. Similar enrichment profiles were demonstrated in patients with primary Sjögren's syndrome, systemic sclerosis, and dermatomyositis. CONCLUSIONS: IFNGS test-high patients overexpressed many gene signatures associated with SLE pathogenesis compared with IFNGS test-low patients, reflecting broad immune activation. These results provide new insights into the molecular heterogeneity underlying SLE pathogenesis, highlighting shared mechanisms beyond type I IFN, across several autoimmune diseases. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01438489 and NCT01283139.

Transforming function of the LSM1 oncogene in human breast cancers with the 8p11-12 amplicon.

Amplification of the 8p11-12 region occurs in 15-20% of breast cancers, but the driving oncogene at this locus has yet to be definitively identified. We mapped the 8p11-12 amplicon in breast cancer cell lines and primary human breast cancers and identified the candidate oncogene human Sm-like protein (hLsm1, LSM1) based on increases in copy number and expression level relative to human mammary epithelial cells. To examine the oncogenic role of LSM1, we overexpressed this gene in MCF10A mammary epithelial cells and inhibited its production in the SUM44 breast cancer cell line, which has a natural amplification and overexpression of LSM1. Our data confirmed that LSM1 is an oncogene from the 8p11-12 amplicon by showing that hLsm1 overexpression induced growth factor-independent proliferation and soft agar colony formation in MCF10A cells, and hLsm1 inhibition in SUM44 cells dramatically reduced soft agar growth. Little is known about hLsm1 function other than its involvement in mRNA degradation; therefore, we used expression microarray analysis to investigate how hLsm1 affects cell transformation in MCF10A and SUM44 cells. We identified numerous genes altered following hLsm1 overexpression common to SUM44 breast cancer cells that play important roles in cell cycle regulation, cell proliferation and other cancer-promoting processes. Future work will continue to characterize these important changes to achieve a more complete understanding of the mechanism of hLsm1's effect on cancer progression.

Pharmacogenomics and translational simulations to bridge indications for an anti-interferon-α receptor antibody.

A type I interferon (IFN) gene signature shared by systemic lupus erythematous (SLE) and systemic sclerosis (SSc) was used to evaluate an anti-type I IFN-α receptor (IFN-αR) monoclonal antibody, MEDI-546, in a phase I trial in SSc. MEDI-546 suppressed IFN signature in blood and skin of SSc patients in a dose-dependent manner. To bridge clinical indications to SLE, we developed a model incorporating (i) pharmacokinetics (PK) and pharmacodynamics (PD) in SSc patients, (ii) internalization kinetics of MEDI-546/IFN-αR complex, and (iii) the different IFN signatures between SSc and SLE. Simulations predicted that i.v. administration of MEDI-546 at 300- or 1,000-mg monthly doses could suppress IFN signature in blood to levels of healthy subjects in 53 and 68% of SLE patients, respectively. An innovative approach utilizing a novel biomarker characterized the PD of MEDI-546 by modeling and simulation and allowed rapid progression of MEDI-546 from a phase I study in SSc to a randomized, multiple-dose phase II trial.

A novel oncogenic role for the miRNA-506-514 cluster in initiating melanocyte transformation and promoting melanoma growth.

Malignant melanoma is the most aggressive form of skin cancer and its incidence has doubled in the last two decades. It represents only 4% of skin cancer cases per year, but causes as many as 74% of skin cancer deaths. Early detection of malignant melanoma is associated with survival rates of up to 90%, but later detection (stage III to stage IV) is associated with survival rates of only 10%. Dysregulation of microRNA (miRNA) expression has been linked to tumor development and progression by functioning either as a tumor suppressor, an oncogene or a metastasis regulator in multiple cancer types. To understand the role of miRNA in the pathogenesis of malignant melanoma and identify biomarkers of metastasis, miRNA expression profiles in skin punches from 33 metastatic melanoma patients and 14 normal healthy donors were compared. We identified a cluster of 14 miRNAs on the X chromosome, termed the miR-506-514 cluster, which was consistently overexpressed in nearly all melanomas tested (30-60 fold, P<0.001), regardless of mutations in N-ras or B-raf. Inhibition of the expression of this cluster as a whole, or one of its sub-clusters (Sub-cluster A) consisting of six mature miRNAs, led to significant inhibition of cell growth, induction of apoptosis, decreased invasiveness and decreased colony formation in soft agar across multiple melanoma cell lines. Sub-cluster A of the miR-506-514 cluster was critical for maintaining the cancer phenotype, but the overexpression of the full cluster was necessary for melanocyte transformation. Our results provide new insights into the functional role of this miRNA cluster in melanoma, and suggest new approaches to treat or diagnose this disease.

[Corrected transposition of great vessels in adult age]. / Korrigierte Transposition der grossen Gefässe im Erwachsenenalter

Two adult cases of corrected transposition of the great arteries are presented. One of the two males had associated ventricular septal defect, the other one presented as an isolated anomaly. The characteristic clinical features are: loud second heart sound with audible pulmonic component of the left sternal border in the absence of pulmonary hypertension. Abnormal precordial impulse upon palpation. Chest X-ray shows absence of pulmonic segment and of the aortic knob with the contour of the ascending aorta to the left of the mediastinum. Ecg anomalies may be multiple; typically anomalous septal Q-waves are consistently absent. Corrected transposition is well tolerated even into adulthood. Prognosis is dominated by assiciated anomalies.