Synergistic upregulation of ADAMTS4 (aggrecanase-1) by cytokines and its suppression in knee osteoarthritic synovial fibroblasts

The ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family includes nine members with aggrecan-degrading activity, i.e., ADAMTS1, 4, 5, 8, 9, 15, 16, 18, and 20. However, their systematic expression profile in knee osteoarthritis (OA) synovium and effects of cytokines and growth factors on the expression in OA synovial fibroblasts remain elusive. In this study, expression of all nine aggrecanolytic ADAMTS species was assessed by quantitative real-time PCR in OA and control normal synovial tissues. OA synovial fibroblasts were treated with interleukin-1α (IL-1α), IL-1β, tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), vascular endothelial growth factor165, and heparin-binding epidermal growth factor, and analyzed for the expression of the ADAMTS species. The signaling pathways and inhibition of ADAMTS4 expression by high-molecular-weight hyaluronan, adalimumab, tocilizumab, and signaling molecule inhibitors were studied. ADAMTS1, 4, 5, 9, and 16 were expressed in OA synovium, but only ADAMTS4 expression was significantly higher in OA as compared to normal synovium. IL-1α, TNF-α, and TGF-β markedly increased ADAMTS4 expression, while their effects were minimal for the other ADAMTS species. ADAMTS4 was synergistically upregulated by treatment with IL-1α and TNF-α, IL-1α and TGF-β, or IL-1α, TNF-α and TGF-β. The signaling molecules' inhibitors demonstrated that IL-1α-induced ADAMTS4 expression is predominantly through TGF-β-associated kinase 1 (TAK1), and the TNF-α-stimulated expression is via TAK1 and nuclear factor-κB (NF-κB). The TGF-β-promoted expression was through the activin receptor-like kinase 5 (ALK5)/Smad2/3, TAK1, and non-TAK1 pathways. Adalimumab blocked TNF-α-stimulated expression. ADAMTS4 expression co-stimulated with IL-1α, TNF-α and TGF-β was abolished by treatment with adalimumab, TAK1 inhibitor, and ALK5/Smad2/3 inhibitor. These data demonstrate marked and synergistic upregulation of ADAMTS4 by IL-1α, TNF-α and TGF-β in OA synovial fibroblasts, and suggest that concurrent therapy with an anti-TNF-α drug and inhibitor(s) may be useful for prevention against aggrecan degradation in OA.

Inhibitory effects of Sanguisorba officinalis root extract on HYBID (KIAA1199)-mediated hyaluronan degradation and skin wrinkling

OBJECTIVES

Hyaluronan (HA), an important constituent of extracellular matrix in the skin, has many biological activities such as hydration that contributes to firmness and bounciness of the skin. We have reported that reduction in HA in the papillary dermis and over-expression of HYBID (HYaluronan Binding protein Involved in hyaluronan Depolymerization, alias KIAA1199 or CEMIP), a key molecule for HA degradation in skin fibroblasts, are implicated in facial skin wrinkling in Japanese and Caucasian women. However, little or no information is available for substances which inhibit the HYBID-mediated HA degradation.

METHODS

Inhibition of Sanguisorba officinalis root extract and ziyuglycoside I, one of the components of Sanguisorba officinalis root extract, to the HYBID-mediated HA degradation was assessed by size-exclusion chromatography of HA depolymerized by stable transfectants of HYBID in HEK293 cells (HYBID/HEK293 cells) or normal human skin fibroblasts (Detroit 551 cells and NHDF-Ad cells). The HYBID mRNA and protein expression was examined by quantitative real-time PCR and immunoblotting in the skin fibroblasts treated with Sanguisorba officinalis root extract, and size distribution of newly produced HA was evaluated by preparing metabolically radiolabelled HA. A double-blind, randomized and placebo-controlled study was carried out in the 21 healthy Japanese women, who were topically treated with the formulation containing Sanguisorba officinalis root extract or the placebo on each side of the face including crow's foot area.

RESULTS

Sanguisorba officinalis root extract, but not ziyuglycoside I, abolished HYBID-mediated HA degradation by HYBID/HEK293 cells. Sanguisorba officinalis root extract also inhibited HYBID-mediated HA degradation in skin fibroblasts by down-regulating HYBID mRNA and protein expression. Although control untreated skin fibroblasts produced polydispersed HA, the cells treated with Sanguisorba officinalis root extract produced only high-molecular-weight HA. Treatment with Sanguisorba officinalis root extract-formulated lotion significantly improved skin elasticity, and reduced skin wrinkling scores at the outer eye corner compared with the placebo formulation.

CONCLUSION

Sanguisorba officinalis root extract showed an anti-HYBID-mediated HA degradation activity and anti-wrinkle activity on human facial skin, which is accompanied by the improvement in elasticity. Our study provides the possibility of a new strategy to inhibit HYBID-mediated HA degradation for anti-wrinkle care.

ADAMTS1 inhibits lymphangiogenesis by attenuating phosphorylation of the lymphatic endothelial cell-specific VEGF receptor

Angiogenesis and lymphangiogenesis play roles in malignant tumor progression, dissemination, and metastasis. ADAMTS1, a member of the matrix metalloproteinase family, is known to inhibit angiogenesis. Recombinant ADAMTS1 was shown to strongly inhibit angiogenesis. We investigated whether ADAMTS1 inhibited lymphangiogenesis in the present study. We examined cell proliferation and cell migration in normal human dermal lymphatic microvascular endothelial cells (HMVEC-dLy) transduced with or without adenoviral human ADAMTS1 gene therapy. We then examined the VEGFC/VEGFR3 signal transduction pathway in ADAMTS1-transduced HMVEC-dLy. Cell proliferation and tube formation in Matrigel were significantly lower with transduced ADAMTS1 than with control (non-transduced HMVEC-dLy). The phosphorylation of VEGFR3 was also attenuated by ADAMTS1 gene therapy in HMVEC-dLy. Immunoprecipitation assays revealed that ADAMTS1 formed a complex with VEGFC. Our results demonstrated that ADAMTS1 inhibited lymphangiogenesis in vitro. The data highlight the new function of ADAMTS1 in the regulation of lymphangiogenesis and the therapeutic potential of ADAMTS1 in cancer therapy.

Tumor growth inhibitory effect of ADAMTS1 is accompanied by the inhibition of tumor angiogenesis

Angiogenesis plays an important role in tumor progression. Several reports have demonstrated that a disintegrin and metalloproteinase with thrombospondin motifs1 (ADAMTS1) inhibited angiogenesis via multiple mechanisms. The aim of this study was to investigate the effect of ADAMTS1 on endothelial cells in vitro and on tumor growth with regard to angiogenesis in vivo. We examined the effects of the transfection of ADAMTS1 using two constructs, full-length ADAMTS1 (full ADAMTS1) and catalytic domain-deleted ADAMTS1 (delta ADAMTS1). Transfection of both the full ADAMTS1 and delta ADAMTS1 gene constructs demonstrated the secretion of tagged-ADAMTS1 protein into the conditioned medium, so we examined the effects of ADAMTS1-containing conditioned medium on endothelial cells. Both types of conditioned media inhibited endothelial tube formation, and this effect was completely abolished after immunoprecipitation of the secreted protein from the medium. Both types of conditioned media also inhibited endothelial cell migration and proliferation. We then examined the impact of ADAMTS1 on endothelial cell apoptosis. Both conditioned media increased the number of Annexin V-positive endothelial cells and caspase-3 activity and this effect was attenuated when z-vad was added. These results indicated that ADAMTS1 induced endothelial cell apoptosis. We next examined the effects of ADAMTS1 gene transfer into tumor-bearing mice. Both full ADAMTS1 and delta ADAMTS1 significantly inhibited the subcutaneous tumor growth. Collectively, our results demonstrated that ADAMTS1 gene transfer inhibited angiogenesis in vitro and in vivo, likely as a result of the induction of endothelial cell apoptosis by ADAMTS1 that occurs independent of the protease activity.

The 3'-untranslated region of ADAMTS1 regulates its mRNA stability

ADAMTS1 (a disintegrin and metalloproteinase with thrombospondin motifs 1) is an inflammatory-induced gene. We have previously reported that ADAMTS1 was strongly but transiently expressed in the infarcted heart. In this study, we investigated whether a 3'-untranslated region (UTR) affects the mRNA stability of this gene. When stimulated with tissue necrosis factor (TNF)-alpha, the expression level of ADAMTS1 mRNA rapidly increased, but the induction of ADAMTS1 mRNA peaked at 6h after stimulation, after which the expression levels of ADAMTS1 mRNA decreased. The 3'-UTR ADAMTS1 mRNA contains multiple adenine and uridine-rich elements, suggesting that the 3'-UTR may regulate gene stability. The addition of actinomycin D, an RNA synthesis inhibitor, demonstrated the decay of induced ADAMTS1 mRNA by TNF-alpha. Furthermore, a region containing multiple AUUUA motifs within the ADAMTS1 3'-UTR destabilized transfected Enhanced Green Fluorescence Protein (EGFP) mRNA expression. These results demonstrated that the ADAMTS1 3'-UTR may regulate the expression of ADAMTS1 mRNA.

Frequent deletion of ING2 locus at 4q35.1 associates with advanced tumor stage in head and neck squamous cell carcinoma

BACKGROUND

Loss of heterozygosity (LOH) in the ING family members has been shown in head and neck squamous cell carcinoma (HNSCC) except for ING2. Like all the other members of ING family, ING2, which is located at chromosome 4q35.1, is a promising tumor suppressor gene (TSG). In this study, we performed LOH analysis of ING2 in HNSCC and compared it with clinicopathological variables.

MATERIALS AND METHODS

We performed LOH analysis in DNAs from 80 paired of normal and HNSCC tissues, using a specifically designed microsatellite marker on chromosome 4q35.1, which detects allelic loss of ING2. TP53 mutation analysis and its relationship with ING2 chromosomal deletion were also performed in available 68 of the samples. The correlation between LOH status and clinicopathological characteristics was evaluated by using statistical methods. The overall survival (OS) and disease free survival (DFS) were also determined.

RESULTS

LOH was detected in 54.6% (30/55) of the informative samples. Statistical significance was obtained between LOH and tumor (T) stage (P = 0.02), application of radiotherapy and chemotherapy. Positive node status (N) appeared to be the only independent prognostic factor for both OS (P = 0.031) and DFS (P = 0.044).

CONCLUSIONS

Our study showed allelic loss of 4q35.1 in HNSCC. The high percentage of LOH suggests ING2 as a candidate TSG in HNSCC. High LOH frequency was statistically associated with advanced T stage, suggesting that ING2 LOH might occur in late stages during HNSCC progression.