OBJECTIVE: Recent investigations have revealed DNA mismatch repair (MMR) gene mutations are closely related with carcinogenesis of endometrial cancer; however the impact of MMR protein expression on prognosis is not determined. Correlations between MMR-related protein expression and clinicopathological factors of endometrial cancers are analyzed in the present study. METHODS: A total of 191 endometrial cancer tissues treated between 1990 and 2007 in our hospital were enrolled. Immunoreactions for MSH2, MLH1, MSH6, and PMS2 on tissue microarray specimens and clinicopathological features were analyzed retrospectively. RESULTS: Seventy-six cases (40%) had at least one immunohistochemical alteration in MMR proteins (MMR-deficient group). There were statistically significant differences of histology, International Federation of Gynecology and Obstetrics (FIGO) stage, and histological grade between MMR-deficient group and the other cases (MMR-retained group). Response rate of first-line chemotherapy in evaluable cases was slightly higher in MMR-deficient cases (67% vs. 44%, p=0.34). MMR-deficient cases had significantly better progression-free and overall survival (OS) compared with MMR-retained cases. Multivariate analysis revealed MMR status was an independent prognostic factor for OS in endometrial cancers. CONCLUSION: MMR-related proteins expression was identified as an independent prognostic factor for OS, suggesting that MMR was a key biomarker for further investigations of endometrial cancers.
Adaptor Proteins, Signal Transducing/deficiency/metabolism ; Adenosine Triphosphatases/deficiency/metabolism ; Adult ; Aged ; Aged, 80 and over ; Chemotherapy, Adjuvant ; *DNA Mismatch Repair ; DNA Repair Enzymes/deficiency/*metabolism ; DNA-Binding Proteins/deficiency/*metabolism ; Endometrial Neoplasms/*diagnosis/drug therapy/genetics/pathology ; Female ; Humans ; Kaplan-Meier Estimate ; Middle Aged ; MutS Homolog 2 Protein/deficiency/metabolism ; Neoplasm Proteins/deficiency/metabolism ; Nuclear Proteins/deficiency/metabolism ; Prognosis ; Retrospective Studies ; Tumor Markers, Biological/*metabolism

Melanoma inhibiting activity/cartilage-derived retinoic acid-sensitive protein (MIA/CD-RAP) is a small soluble protein secreted from malignant melanoma cells and from chondrocytes. Recently, we revealed that MIA/CD-RAP can modulate bone morphogenetic protein (BMP)2-induced osteogenic differentiation into a chondrogenic direction. In the current study we aimed to find the molecular details of this MIA/CD-RAP function. Direct influence of MIA on BMP2 by protein-protein-interaction or modulating SMAD signaling was ruled out experimentally. Instead, we revealed inhibition of ERK signaling by MIA/CD-RAP. This inhibition is regulated via binding of MIA/CD-RAP to integrin alpha5 and abolishing its activity. Active ERK signaling is known to block chondrogenic differentiation and we revealed induction of aggrecan expression in chondrocytes by treatment with MIA/CD-RAP or PD098059, an ERK inhibitor. In in vivo models we could support the role of MIA/CD-RAP in influencing osteogenic differentiation negatively. Further, MIA/CD-RAP-deficient mice revealed an enhanced calcified cartilage layer of the articular cartilage of the knee joint and disordered arrangement of chondrocytes. Taken together, our data indicate that MIA/CD-RAP stabilizes cartilage differentiation and inhibits differentiation into bone potentially by regulating signaling processes during differentiation.
Animals ; Bone Morphogenetic Proteins/metabolism ; Cartilage/*cytology/metabolism ; *Cell Differentiation ; Chondrocytes/cytology/enzymology ; Extracellular Matrix Proteins/deficiency/*metabolism ; Extracellular Signal-Regulated MAP Kinases/metabolism ; Humans ; Integrin alpha5/metabolism ; Mesenchymal Stem Cells/cytology/metabolism ; Mice ; Neoplasm Proteins/deficiency/*metabolism ; Osteogenesis ; Protein Binding ; Signal Transduction ; Smad Proteins/metabolism

The paracaspase MALT1 is essential for the activation of NF-κB in response to T cell receptor (TCR) stimulation. It recruits downstream TRAF6 and activates the E3 ligase activity of TRAF6 to polyubiquitinate several targets, which ultimately leads to NF-κB activation. Here we identified ubiquitin-specific protease 2a (USP2a) as a MALT1-associated protein by biochemical affinity purification. Endogenous USP2a constitutively interacted with TRAF6, but dynamically interacted with MALT1 and CARMA1 in a stimulation-dependent manner. RNA interference (RNAi)-mediated silencing of USP2a attenuated TCR-induced NF-κB activation and production of interleukin-2 (IL-2). In addition, the ubiquitination of MALT1 and TRAF6 were both suppressed by USP2a knockdown. By knockdown and reconstitution assays, we found that USP2a mediated the interaction between MALT1 and TRAF6 in a catalytic activity-dependent manner. Furthermore, USP2a deSUMOylated TRAF6. Our findings implicate that USP2a plays an important role in TCR signaling by deSUMOylating TRAF6 and mediating TRAF6-MALT1 interaction.
Caspases ; metabolism ; Endopeptidases ; deficiency ; genetics ; metabolism ; Gene Knockdown Techniques ; HEK293 Cells ; Humans ; Interleukin-2 ; biosynthesis ; Jurkat Cells ; Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein ; NF-kappa B ; metabolism ; Neoplasm Proteins ; metabolism ; Receptors, Antigen, T-Cell ; metabolism ; Signal Transduction ; Sumoylation ; TNF Receptor-Associated Factor 6 ; metabolism