Back to Authors

Leontovich, Alexey A.

0009-0002-2014-8996

Mayo Clinic

Mayo Clinic

Citations 52

Gene Expression Profiling of Orbital Adipose Tissue from Patients with Graves’ Ophthalmopathy: A Potential Role for Secreted Frizzled-Related Protein-1 in Orbital Adipogenesis
Kumar, Seema , Leontovich, Alexey A. , Coenen, Michael J., Bahn, Rebecca S.

The Journal of Clinical Endocrinology & Metabolism | August 8, 2005 | Volume: 90 | Issue: 8 | Pages: 4730-4735

10.1210/jc.2004-2239 Get It

Context: The signs and symptoms of Graves’ ophthalmopathy (GO) result from inflammation and increased volume of the orbital adipose tissues and extraocular muscles. Objective: Our objective was to identify differentially regulated genes that may be involved in stimulating the orbital adipose tissue expansion seen in GO. Design: Gene expression profiling was used to compare genes expressed in orbital adipose tissues from GO patients and normal individuals. Setting: The study took place at a private practice tertiary referral center. Patients: Orbital adipose tissues were collected at transantral orbital decompression surgery from 20 euthyroid patients undergoing this procedure for severe GO and at early autopsy from eight normal individuals having no evidence of thyroid or ocular disease. Results: Of the 12,686 genes analyzed, 25 known genes were increased in expression (>4-fold) in GO orbital tissues, whereas 11 genes were decreased (>4-fold). Up-regulated genes, confirmed by quantitative RT-PCR, included secreted frizzled-related protein-1 (sFRP-1; 18.5-fold) and several adipocyte-related genes, including peroxisome proliferator activated receptor-γ (44.1-fold) and adiponectin (25-fold). Treatment in vitro of GO orbital preadipocytes with recombinant sFRP-1 (100 nm) significantly increased adiponectin (2.0-fold; P < 0.05), leptin (7-fold; P < 0.002), and TSH receptor mRNA (13-fold; P < 0.003) levels and enhanced Oil red-O staining in the cultures. Conclusions: These results support the concept that orbital adipogenesis is enhanced in GO and suggest that elevated levels of sFRP-1 in the GO orbit may be involved in stimulating this pathogenic process.
Proteomic analysis of mantle-cell lymphoma by protein microarray
Leontovich, Alexey A. , Loegering, David A., Dai, Nga T., Krajnik, Kelly L., Stenson, Mary, Melhem, Mona F., Novak, Anne J. , Ansell, Stephen M. , Ghobrial, Irene M. , McCormick, Daniel , Kaufmann, Scott H. , Witzig, Thomas E.

Blood | January 14, 2005 | Volume: 105 | Issue: 9 | Pages: 3722-3730

10.1182/blood-2004-10-3999 Get It

Abstract Mantle-cell lymphoma (MCL) is a unique subtype of B-cell non-Hodgkin lymphoma (NHL) that behaves aggressively and remains incurable. In order to understand the pathogenesis of MCL and design new therapies, it is important to accurately analyze molecular changes in pathways dysregulated in MCL. We used antibody microarrays to compare patterns of protein expression between CD19+ purified B lymphocytes from normal tonsil and 7 cases of histologically confirmed MCL. Protein overexpression was defined as a higher than 1.3-fold or 2-fold increase in at least 67% of tumor samples compared with normal B-cell control. Of the polypeptides, 77 were overexpressed using the higher than 1.3-fold cutoff, and 13 were overexpressed using the 2-fold cutoff. These included cell cycle regulators (regulator of chromosome condensation 1 [RCC1], murine double minute 2 [MDM2]), a kinase (citron Rho-interacting kinase [CRIK]), chaperone proteins (heat shock 90-kDa protein [Hsp90], Hsp10), and phosphatase regulators (A-kinase anchor protein 1 [AKAP149], protein phosphatase 5 [PP5], and inhibitor 2). The elevated expression of some of these polypeptides was confirmed by immunoblotting and immunohistochemistry, whereas elevated expression of others could not be confirmed, illustrating the importance of confirmatory studies. This study describes a novel technique that identifies proteins dysregulated in MCL.