Rheumatoid arthritis (RA) and osteoarthritis (OA), two common types of arthritis, affect the joints mainly by targeting the synovium and cartilage. Increasing evidence indicates that a significant network connects synovitis and cartilage destruction during the progression of arthritis. We recently demonstrated that hypoxia-inducible factor (HIF)-2alpha causes RA and OA by regulating the expression of catabolic factors in fibroblast-like synoviocytes (FLS) or chondrocytes. To address the reciprocal influences of HIF-2alpha on FLS and chondrocytes, we applied an in vitro co-culture system using a transwell apparatus. When co-cultured with HIF-2alpha-overexpressing chondrocytes, FLS exhibited increased expression of matrix metalloproteinases and inflammatory mediators, similar to the effects induced by tumor-necrosis factor (TNF)-alpha treatment of FLS. Moreover, chondrocytes co-cultured with HIF-2alpha-overexpressing FLS exhibited upregulation of Mmp3 and Mmp13, which is similar to the effects induced by interleukin (IL)-6 treatment of chondrocytes. We confirmed these differential HIF-2alpha-induced effects via distinct secretory mediators using Il6-knockout cells and a TNF-alpha-blocking antibody. The FLS-co-culture-induced gene expression changes in chondrocytes were significantly abrogated by IL-6 deficiency, whereas TNF-alpha neutralization blocked the alterations in gene expression associated with co-culture of FLS with chondrocytes. Our results further suggested that the observed changes might reflect the HIF-2alpha-induced upregulation of specific receptors for TNF-alpha (in FLS) and IL-6 (in chondrocytes). This study broadens our understanding of the possible regulatory mechanisms underlying the crosstalk between the synovium and cartilage in the presence of HIF-2alpha, and may suggest potential new anti-arthritis therapies.
Animals ; Arthritis/genetics/*immunology/pathology ; Arthritis, Rheumatoid/genetics/immunology/pathology ; Basic Helix-Loop-Helix Transcription Factors/genetics/*immunology ; Cells, Cultured ; Chondrocytes/immunology/metabolism/*pathology ; Coculture Techniques ; Fibroblasts/immunology/metabolism/*pathology ; Gene Expression Regulation ; Interleukin-6/genetics/*immunology ; Male ; Mice ; Mice, Inbred C57BL ; Osteoarthritis/genetics/immunology/pathology ; Synovial Membrane/immunology/metabolism/*pathology ; Tumor Necrosis Factor-alpha/genetics/*immunology ; Up-Regulation

OBJECTIVETo evaluate the immunophenotype conversion of fibroblasts and its clinical significance in the process of breast tumor stromal remodeling.

METHODSCD34, FAP-α, p63 and a-SMA were detected by immunohistochemistry in 273 breast biopsies, including 60 normal breast tissues, 46 atypical ductal hyperplasia (ADH), 60 ductal carcinoma in situ (DCIS), 47 DCIS microinvasive carcinoma (DCIS-MI) and 60 invasive ductal carcinoma (IDC).

RESULTSThe positive expression rates of CD34, FAP-α and α-SMA in the stromal fibroblasts of normal breast tissues were 93.3%, 6.7% and 18.3%, respectively. Those in the stromal fibroblasts of ADH tissues were 95.7%, 4.3% and 10.9%, respectively. Those in the stromal fibroblasts of DCIS tissues were 95.0%, 8.3% and 15.0%, respectively. Those in the IDC tissues were 35.0%, 85.0% and 93.3%, respectively. The expressions of CD34, α-SMA and FAP-α in the stromal fibroblasts of normal, ASH and DCIS breast tissues did not show significant differences (χ(2) = 1.142, P = 0.896). The main immunophenotype of stromal fibroblasts in the tumor-host interface at the invasive front of ADH and DCIS lesions was CD34(+)α-SMA(+)FAP-α(+). There were statistically significant differences in the expression of CD34, α-SMA and FAP-α between IDC and ADH, DCIS and normal breast tissues (χ(2) = 8.351, P < 0.001). The immunophenotype of stromal fibroblasts in the IDC and DCIS-MI breast tissues was CD34(-) α-SMA(+) FAP-α(+).

CONCLUSIONSImmunophenotype conversion from CD34(+) α-SMA(-) FAP-α(-) to CD34(-) α-SMA(+)FAP-α(+) may be a sensitive indicator to judge whether DCIS has microinvasion. Detection of the immunophenotype conversion of stromal fibroblasts may be helpful to determine the presence of microinvasion, and to improve the diagnostic accuracy rate of DCIS.

Breast ; Breast Neoplasms ; immunology ; pathology ; Carcinoma in Situ ; Carcinoma, Ductal, Breast ; Carcinoma, Intraductal, Noninfiltrating ; Fibroblasts ; immunology ; Gelatinases ; metabolism ; Humans ; Hyperplasia ; Immunohistochemistry ; Immunophenotyping ; Membrane Proteins ; metabolism ; Serine Endopeptidases ; metabolism

Myeloid-related protein (MRP)8/MRP14 is an endogenous Toll-like receptor 4 (TLR4) ligand and is abundant in synovial fluid (SF) of rheumatoid arthritis (RA) patients. Belonging to damage-associated molecular patterns, it amplifies proinflammatory mediators and facilitates a wide range of inflammatory and autoimmune diseases. Interleukin (IL)-17-producing T-helper (Th)17 cells have a crucial role in RA pathogenesis, and IL-6 is the key factor promoting Th17 differentiation. We investigated whether the level of MRP8/MRP14 is positively associated with IL-6 and IL-17 levels in RA SF and found that MRP8/MRP14 level had a significant correlation with IL-6 and IL-17 levels in RA SF. We also observed that MRP8-induced IL-17 production by peripheral blood mononuclear cells but MRP14 did not. Upon stimulation with MRP8, IL-6 production was enhanced by RA fibroblast-like synoviocytes (FLS) and was further elevated by coculturing RA FLS with activated CD4+ T cells. Moreover, we demonstrated that MRP8-activated IL-6 production by RA FLS promoted differentiation of Th17 cells using the coculture system consisting of CD4+ T cells and RA FLS. In addition, IL-6 blockade attenuated Th17 polarization of CD4+ T cells in the cocultures. Inhibitor studies revealed that MRP8 increased IL-6 production in RA FLS via TLR4/phosphoinositide 3-kinase/nuclear factor-kappaB and mitogen-activated protein kinase signaling pathways. Our results show that MRP8 has a crucial role in stimulating IL-6 expression by RA FLS, and subsequently promotes Th17 differentiation in RA, suggesting that neutralizing MRP8 level in RA synovium may be an effective therapeutic strategy in RA treatment.
ATP-Binding Cassette Transporters/*metabolism ; Adult ; Aged ; Arthritis, Rheumatoid/*pathology ; CD4-Positive T-Lymphocytes/metabolism ; Calgranulin B/metabolism ; Cell Differentiation/*immunology ; Fibroblasts/*metabolism/pathology ; Humans ; Inflammation Mediators/metabolism ; Interleukin-17/metabolism ; Interleukin-6/*biosynthesis ; Middle Aged ; Signal Transduction/immunology ; Synovial Fluid/cytology ; Synovial Membrane/metabolism/pathology ; Th17 Cells/*pathology ; Toll-Like Receptor 4/metabolism ; *Up-Regulation

OBJECTIVE: To investigate a possible role of CD147 in the production of matrix metalloproteinase-9 (MMP-9) by fibroblasts and the invasion of melanoma cells. METHODS: We cocultured CD147-expression melanoma cells with fibroblasts and examined the MMP-9 expression of fibroblasts by zymography and the invasion of melanoma cells by transwell invasion assay. RESULTS: MMP-9 expression was enhanced in conditioned media, while cocultured with melanoma cells in a dose-dependent manner, and CD147 antibody inhibited the production of MMP-9 in the fibroblasts. When fibroblasts were cultured at the bottom of the lower compartment of transwell invasion model, the number of melanoma cells that invaded significantly increased. Addition of anti-CD147 antibody to the upper compartment transwell invasion model resulted in the significant inhibition of the melanoma cell invasion in reconstituted basement membrane. CONCLUSION CD147 expressed in melanoma cells plays an important role in the melanoma cell invasion by stimulating the production of MMP-9 by fibroblasts.
Basigin ; immunology ; pharmacology ; Coculture Techniques ; Fibroblasts ; cytology ; metabolism ; Humans ; Matrix Metalloproteinase 9 ; biosynthesis ; genetics ; Melanoma ; pathology ; Neoplasm Invasiveness ; Tumor Cells, Cultured

Cytosolic retinoic acid-inducible gene I (RIG-I) is an important innate immune RNA sensor and can induce antiviral cytokines, e.g., interferon-β (IFN-β). Innate immune response to hepatitis B virus (HBV) plays a pivotal role in viral clearance and persistence. However, knowledge of the role that RIG-I plays in HBV infection is limited. The woodchuck is a valuable model for studying HBV infection. To characterize the molecular basis of woodchuck RIG-I (wRIG-I), we analyzed the complete coding sequences (CDSs) of wRIG-I, containing 2778 base pairs that encode 925 amino acids. The deduced wRIG-I protein was 106.847 kD with a theoretical isoelectric point (pI) of 6.07, and contained three important functional structures [caspase activation and recruitment domains (CARDs), DExD/H-box helicases, and a repressor domain (RD)]. In woodchuck fibroblastoma cell line (WH12/6), wRIG-I-targeted small interfering RNA (siRNA) down-regulated RIG-I and its downstrean effector-IFN-β transcripts under RIG-I' ligand, 5'-ppp double stranded RNA (dsRNA) stimulation. We also measured mRNA levels of wRIG-I in different tissues from healthy woodchucks and in the livers from woodchuck hepatitis virus (WHV)-infected woodchucks. The basal expression levels of wRIG-I were abundant in the kidney and liver. Importantly, wRIG-I was significantly up-regulated in acutely infected woodchuck livers, suggesting that RIG-I might be involved in WHV infection. These results may characterize RIG-I in the woodchuck model, providing a strong basis for further study on RIG-I-mediated innate immunity in HBV infection.
Animals ; Cell Line, Tumor ; Cloning, Molecular ; DEAD Box Protein 58 ; antagonists & inhibitors ; genetics ; immunology ; Fibroblasts ; immunology ; pathology ; Gene Expression ; Hepatitis B ; genetics ; immunology ; pathology ; veterinary ; Hepatitis B Virus, Woodchuck ; Immunity, Innate ; Interferon-beta ; genetics ; immunology ; Isoelectric Point ; Kidney ; immunology ; pathology ; virology ; Liver ; immunology ; pathology ; virology ; Marmota ; genetics ; immunology ; virology ; Open Reading Frames ; Protein Domains ; RNA, Double-Stranded ; RNA, Small Interfering ; genetics ; metabolism ; Rodent Diseases ; genetics ; immunology ; pathology ; virology

The interactions between the tumor microenvironment and tumor cells determine the behavior of the primary tumors. Whether cancer-associated fibroblasts (CAF) have a tumor progressive or a protective role likely depends on the type of tumor cells and the CAF subpopulation. In the present study, we analyzed the prognostic significance of CAF subpopulations in colorectal cancer (CRC). CAF phenotypes were analyzed in 302 CRC patients by using antibodies against podoplanin (PDPN), alpha-smooth muscle actin (alpha-SMA), and S100A4. The relationship between the CAF phenotypes and 11 clinicopathological parameters were evaluated and their prognostic significance was analyzed from the disease-free and overall survival times. We observed that at the tumor invasive front, PDPN CAFs were present in 40% of the cases, and S100A4 or alpha-SMA CAFs were detected in all the cases. PDPN/S100A4 and alpha-SMA/S100A4 dual-stained CAFs were observed in 10% and 40% of the cases, respectively. The PDPN+ CAFs were associated with 6 favorable clinicopathological parameters and prolonged disease-free survival time. The PDPN-/alpha-SMA(high) CAFs were associated with 6 aggressive clinicopathological parameters and tended to exhibit shorter disease-free survival time. On the other hand, the PDPN-/S100A4(high) CAFs were associated with 2 tumor progression parameters, but not with disease prognosis. The PDPN+ CAF phenotype is distinct from the alpha-SMA or S100A4 CAFs in that it is associated with less aggressive tumors and a favorable prognosis, whereas the PDPN-/alpha-SMA(high) or PDPN-/S100A4(high) CAFs are associated with tumor progression in CRC. These findings suggest that CAFs can be a useful prognostic biomarker or potential targets of anti-cancer therapy in CRC.
Actins/immunology/*metabolism ; Adult ; Aged ; Aged, 80 and over ; Antibodies/immunology ; Carcinoembryonic Antigen/blood ; Colorectal Neoplasms/*diagnosis/mortality/pathology ; Disease-Free Survival ; Female ; Fibroblasts/cytology/metabolism ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Membrane Glycoproteins/immunology/*metabolism ; Middle Aged ; Neoplasm Staging ; Phenotype ; Prognosis ; S100 Proteins/immunology/*metabolism ; Tumor Markers, Biological/metabolism

Down syndrome critical region 1 (DSCR1), an oxidative stress-response gene, interacts with calcineurin and represses its phosphatase activity. Recently it was shown that hydrogen peroxide inactivates calcineurin by proteolytic cleavage. Based on these facts, we investigated whether oxidative stress affects DSCR1-mediated inactivation of calcineurin. We determined that overexpression of DSCR1 leads to increased proteolytic cleavage of calcineurin. Convertsely, knockdown of DSCR1 abolished calcineurin cleavage upon treatment with hydrogen peroxide. The PXIIXT motif in the COOH-terminus of DSCR1 is responsible for both binding and cleavage of calcineurin. The knockdown of overexpressed DSCR1 in DS fibroblast cells also abrogated calcineurin proteolysis by hydrogen peroxide. These results suggest that DSCR1 has the ability to inactivate calcineurin by inducing proteolytic cleavage of calcineurin upon oxidative stress.
Adenoviridae/genetics ; Adult ; Animals ; Calcineurin/antagonists & inhibitors/*metabolism ; Cells, Cultured ; Chromatin Immunoprecipitation ; Down Syndrome/*metabolism/pathology ; Fibroblasts/metabolism/pathology ; Humans ; Hydrogen Peroxide/pharmacology ; Immunoglobulin G/immunology ; Intracellular Signaling Peptides and Proteins/*physiology ; Male ; Mice ; Mice, Inbred ICR ; Muscle Proteins/*physiology ; Neuroblastoma/genetics/metabolism/pathology ; Neurons/cytology/metabolism ; Oxidants/pharmacology ; Oxidative Stress ; Peptide Fragments/immunology ; RNA, Messenger/genetics/metabolism ; RNA, Small Interfering/pharmacology ; Rabbits ; Reverse Transcriptase Polymerase Chain Reaction ; Skin/pathology ; Young Adult

OBJECTIVETo investigate the expression of discoidin domain receptor 2 (DDR2) of fibroblast-like synovial cells in improved adjuvant-induced animal (AIA) model for rheumatoid arthritis (RA) and to provide evidence for DDR2's antagonist use clinically.

METHODSAIA was modified by administrating 0.1 mL of complete Freund's adjuvant (CFA, mixed with 5 mg Bacillus Calmette-Guerin vaccine/mL) into rats' right hind paws and 0.125 mL tumor necrosis factor-alpha (2 U/mL) into right ankles and subpatellar fatty tissue. The expression of DDR2 in fibroblast-like synovial cells was assessed using immunohistochemistry, immunofluorescence histochemistry, and in situ hybridization methods. Levels of anti-collagen II antibody were measured using enzyme-linked immunosorbent assay.

RESULTSGiven the terms mentioned above, we found a more practical rat model, apparently decreasing immunization time (average 3-5 days). DDR2 can be detected upon the 15th day of immunization; expression gradually increased with time going on, and reaching a peak 35 days after immunization before gradually decreasing. Serum anti-collagen II antibody showed similar expression patterns as DDR2, but reached peak later than DDR2, about 40 days after immunization.

CONCLUSIONRegular expression of DDR2 in animal models infers its important role in the pathological process of RA.

Animals ; Antibodies ; blood ; Arthritis, Experimental ; etiology ; metabolism ; Arthritis, Rheumatoid ; chemically induced ; metabolism ; BCG Vaccine ; Collagen Type II ; immunology ; Discoidin Domain Receptors ; Female ; Fibroblasts ; drug effects ; metabolism ; pathology ; Freund's Adjuvant ; Rats ; Rats, Sprague-Dawley ; Receptor Protein-Tyrosine Kinases ; metabolism ; Receptors, Mitogen ; metabolism ; Synovial Fluid ; cytology ; metabolism

Triptolide (TPT), an active compound extracted from Chinese herb Tripterygium wilfordii , has been used in therapy of rheumatoid arthritis (RA). In this study, after synovial fibroblasts from rheumatoid arthritis (RASFs) were treated with TPT, we investigated its effect on the differentiation of Th17 cells. Firstly, the mRNA level of cyclooxygenase (COX) wad detected by qRT-PCR and the protein level of prostaglandin E2 (PGE2) was tested by ELISA in RASFs treated with different concentrations (0, 10, 50, 100 nmol L-1 ) of TPT. Then after TPT pre-treated RASFs and RA CD4 + T cells wer e co-cultured for 3 days in the presence or absence of PGE2, IL-17 and IFN-gamma production in CD4 T cell subsets were detected by flow cytometry. The results showed TPT decreased the mRNA experssion of COX2 and the secretion of PGE2 in RASFs in a dose-dependent manner(P <0. 05). We further found that differentiation of Thl7 cells was downregulated in a dose-dependent manner, and exogenous PGE2 could reverse the inhibition of Th17 cell differentiation(P <0. 05). Taken together, our results demonstrated that TPT inhibited the mRNA level of COX2 and the secretion of PGE2 in RASFs, which partly led to impaired Th17 cell differentiation in vitro.
Arthritis, Rheumatoid ; drug therapy ; enzymology ; immunology ; Cell Differentiation ; drug effects ; Cell Line ; Cyclooxygenase 2 ; genetics ; metabolism ; Dinoprostone ; metabolism ; Diterpenes ; pharmacology ; Epoxy Compounds ; pharmacology ; Fibroblasts ; drug effects ; immunology ; Gene Expression Regulation, Enzymologic ; drug effects ; Humans ; Middle Aged ; Phenanthrenes ; pharmacology ; Synovial Fluid ; drug effects ; Th17 Cells ; drug effects ; pathology