IgG4-ROD and orbital MALT lymphoma

The molecular pathogenesis of orbital lymphoproliferative disorders, such as immunoglobulin G4-related ophthalmic disease (IgG4-ROD) and orbital mucosa-associated lymphoid tissue (MALT) lymphoma, remains essentially unknown. Differentiation between the two disorders, which is important since work-up and treatment can vary greatly, is often challenging due to the lack of specific biomarkers. Although miRNAs play an important role in the regulation of carcinogenesis and inflammation, the relationship between miRNA and orbital lymphoproliferative diseases remains unknown. A comprehensive analysis of 2,565 miRNAs was performed in biopsied specimens and serum of 17 cases with IgG4-ROD and 21 cases with orbital MALT lymphoma. We identified specific miRNA signatures, their miRNA target pathways, and network analysis associated with IgG4-ROD and orbital MALT lymphoma. Machine-learning analysis identified miR-202-3p and miR-7112-3p as the best discriminators of IgG4-ROD and orbital MALT lymphoma, respectively. In the tissue pathway, Longevity regulating pathway in IgG4-ROD and MAPK signaling pathway in orbital MALT lymphoma were most enriched by downregulated miRNAs. This is the first evidence of the miRNA profile in biopsied specimens and serum of patients with IgG4-ROD and orbital MALT lymphoma. These data will be useful for developing diagnostic and therapeutic interventions, as well as elucidating of these disorders. A total of 14 biopsied specimen of patients with 6 IgG4 related ophthalmic disease (IgG4-ROD) and 8 orbital mucosa associated lymphoid tissue (MALT) lymphoma and a total of 35 serum of patients with 11 IgG4-ROD, 13 orbital MALT lymphoma and 11 healthy individual were characterized using the 3D-Gene® Human miRNA Oligo Chip (Toray Industries, Inc.).