Immunoregulatory Monocyte Subset Promotes Metastasis Associated With Therapeutic Intervention for Primary Tumor.

Systemic and local inflammation associated with therapeutic intervention of primary tumor occasionally promotes metastatic recurrence in mouse and human. However, it remains unclear what types of immune cells are involved in this process. Here, we found that the tissue-repair-promoting Ym1+Ly6Chi monocyte subset expanded as a result of systemic and local inflammation induced by intravenous injection of lipopolysaccharide or resection of primary tumor and promoted lung metastasis originating from circulating tumor cells (CTCs). Deletion of this subset suppressed metastasis induced by the inflammation. Furthermore, transfer of Ym1+Ly6Chi monocytes into naïve mice promoted lung metastasis in the mice. Ym1+Ly6Chi monocytes highly expressed matrix metalloproteinase-9 (MMP-9) and CXCR4. MMP-9 inhibitor and CXCR4 antagonist decreased Ym1+Ly6Chi-monocyte-promoted lung metastasis. These findings indicate that Ym1+Ly6Chi monocytes are therapeutic target cells for metastasis originating from CTCs associated with systemic and local inflammation. In addition, these findings provide a novel predictive cellular biomarker for metastatic recurrence after intervention for primary tumor.

Lysophosphatidic Acid Augments the Gene Expression and Production of Matrix Metalloproteinases-1 and -3 in Human Synovial Fibroblasts in Vitro.

Rheumatoid arthritis (RA) is an inflammatory disease with joint dysfunction following cartilage degradation. The level of lysophosphatidic acid (LPA) has been reported to be augmented in human synovial fluid from patients with RA. However, it remains to be elucidated whether LPA participates in cartilage destruction. In the present study, we have demonstrated that the production of promatrix metalloproteinases (proMMPs)-1 and -3 was augmented along with an increase of extracellular signal-regulated kinase (ERK)1/2 phosphorylation through LPA receptor 1 (LPAR1) in human synovial fibroblasts. These results suggest that LPA transcriptionally increases MMP production by the activation of an LPAR1/ERK1/2 signal pathway in human synovial fibroblasts. Thus, LPA is likely to be a pathological candidate for cartilage degradation in RA.

Involvement of Catechols in Acteoside in the Activation of Promatrix Metalloproteinase-2 and Membrane Type-1-Matrix Metalloproteinase Expression via a Phosphatidylinositol-3-Kinase Pathway in Human Dermal Fibroblasts.

Granulation tissue formation during skin wound healing requires the migration and proliferation of dermal fibroblasts in the wound site, where a subsequent remodeling of extracellular matrices (ECM) occurs. An abnormality of ECM remodeling within the healing wound leads to fibrosis and a contracted scar. To evaluate whether acteoside, a phenylethanoid glycoside isolated from the leaves of Rehmannia glutinosa LIBOSCH., exhibits wound-healing actions, we examined the effect of acteoside on the expression of matrix metalloproteinases (MMPs) in normal human dermal fibroblasts (NHDF). Acteoside dose- and time-dependently augmented the activation of the precursor of MMP-2 (proMMP-2/progelatinase A) in untreated- and interleukin-1ß-treated NHDF, while the alteration of the MMP-2 gene expression was negligible. The acteoside-induced proMMP-2 activation was associated with the augmented membrane-type 1 MMP (MT1-MMP) expression in the NHDF. In addition, the proMMP-2 activation was enhanced by two aglycones in acteoside: caffeic acid and 3,4-dihydroxyphenylethanol, which consist of catechol. However, there was no change in the proMMP-2 activation in other catechol derivatives: homovanillyl alcohol- and homovanillic acid-treated NHDF, indicating that catechols in acteoside were requisite for the regulation of the MMP activation and expression in NHDF. Furthermore, the proMMP-2 activation by acteoside was selectively inhibited by LY294002, a potent phosphatidylinositol-3-kinase (PI3K) inhibitor. These results provide novel evidence that acteoside augments proMMP-2 activation along with an increase in MT1-MMP expression through a PI3K signal pathway in NHDF. Thus, acteoside is likely to be an attractive candidate that facilitates ECM remodeling in the skin wound repair process.

Anti-arthritic actions of ß-cryptoxanthin against the degradation of articular cartilage in vivo and in vitro.

An inverse correlation between the morbidity of rheumatoid arthritis and daily intake of ß-cryptoxanthin has been epidemiologically shown. In this study, we investigated the effects of ß-cryptoxanthin on the metabolism of cartilage extracellular matrix in vivo and in vitro. Oral administration of ß-cryptoxanthin (0.1-1 mg/kg) to antigen-induced arthritic rats suppressed the loss of glycosaminoglycans in articular cartilage, which is accompanied by the interference of aggrecanase-mediated degradation of aggrecan. Inhibition of the interleukin 1α (IL-1α)-induced aggrecan degradation by ß-cryptoxanthin was also observed with porcine articular cartilage explants in culture. ß-Cryptoxanthin (1-10 µM) dose-dependently down-regulated the IL-1α-induced gene expression of aggrecanase 1 (ADAMTS-4) and aggrecanase 2 (ADAMTS-5) in cultured human chondrocytes. Moreover, ß-cryptoxanthin was found to augment the gene expression of aggrecan core protein in chondrocytes. These results provide novel evidence that ß-cryptoxanthin exerts anti-arthritic actions and suggest that ß-cryptoxanthin may be useful in blocking the progression of rheumatoid arthritis and osteoarthritis.

A novel functional site of extracellular matrix metalloproteinase inducer (EMMPRIN) that limits the migration of human uterine cervical carcinoma cells.

EMMPRIN (extracellular matrix metalloproteinase inducer)/CD147, a membrane-bound glycoprotein with two extracellular loop domains (termed loops I and II), progresses tumor invasion and metastasis by increasing the production of matrix metalloproteinase (MMP) in peritumoral stoma cells. EMMPRIN has also been associated with the control of migration activity in some tumor cells, but little is known about how EMMPRIN regulates tumor cell migration. In the present study, EMMPRIN siRNA suppressed the gene expression and production of EMMPRIN in human uterine cervical carcinoma SKG-II cells. An in vitro scratch wound assay showed enhancement of migration of EMMPRIN-knockdown SKG-II cells. In addition, the SKG-II cell migration was augmented by adding an E. coli-expressed human EMMPRIN mutant with two extracellular loop domains (eEMP-I/II), which bound to the cell surface of SKG-II cells. However, eEMP-I/II suppressed the native EMMPRIN-mediated augmentation of proMMP-1/procollagenase-1 production in a co-culture of the SKG-II cells and human uterine cervical fibroblasts, indicating that the augmentation of SKG-II cell migration resulted from the interference of native EMMPRIN functions by eEMP-I/II on the cell surface. Furthermore, a systematic peptide screening method using nine synthetic EMMPRIN peptides coding the loop I and II domains (termed EM1-9) revealed that EM9 (170HIENLNMEADPGQYR184) facilitated SKG-II cell migration. Moreover, SKG-II cell migration was enhanced by administration of an antibody against EM9, but not EM1 which is a crucial site for the MMP inducible activity of EMMPRIN. Therefore, these results provide novel evidence that EMMPRIN on the cell surface limits the cell migration of human uterine cervical carcinoma cells through 170HIENLNMEADPGQYR184 in the loop II domain. Finally, these results should provide an increased understanding of the functions of EMMPRIN in malignant cervical carcinoma cells, and could contribute to the development of clinical strategies for cervical cancer therapy.

Action mechanisms of complementary and alternative medicine therapies for rheumatoid arthritis / 中国结合医学杂志

Rheumatoid arthritis (RA) is characterized as a chronic inflammatory disease in joints and concomitant destruction of cartilage and bone. Cartilage extracellular matrix components, such as type II collagen and aggrecan are enzymatically degraded by matrix metalloproteinases (MMPs) and aggrecanases in RA. Currently, treatments targeting cytokines, including anti-tumor necrosis factor (TNF) α antibodies, soluble TNF receptor, anti-interleukin (IL)-6 receptor antibody, and IL-1 receptor antagonist, are widely used for treating RA in addition to antiantiinflammatory agents and disease-modifying antirheumatic drugs (DMARDs), such as inflmethotrexate, but these treatments have some problems, especially in terms of cost and the increased susceptibility of patients to infection in addition to the existence of low-responders to these treatments. Therefore, therapeutics that can be safely used for an extended period of time would be preferable. Complementary and alternative medicines including traditional Chinese medicines (TCM) have been used for the arthritic diseases through the ages. Recently, there are many reports concerning the anti-arthritic action mechanisms of TCM-based herbal formulas and crude herbal extracts or isolated ingredients. These natural herbal medicines are thought to moderately improve RA, but they exert various actions for the treatment of RA. In this review, the current status of the mechanism exploration of natural compounds and TCM-based herbal formulas are summarized, focusing on the protection of cartilage destruction in arthritic diseases including RA and osteoarthritis.

Anti-arthritic action mechanisms of natural chondroitin sulfate in human articular chondrocytes and synovial fibroblasts.

To clarify the exact anti-arthritic action mechanisms of chondroitin sulfate (CS), we evaluated the effects of CS derived from shark cartilage (CS-SC) composed mainly of chondroitin-6-sulfate and porcine trachea cartilage (CS-PC) composed mostly of chondrotin-4-sulfate on the functions of human articular chondrocytes and synovial fibroblasts. Both CS-SC and CS-PC (from 1 to 100 mug/ml) effectively suppressed the interleukin (IL)-1beta (10 ng/ml)-enhanced gene expression of aggrecanase-1/a disintegrin and metalloproteinase with thrombospondin-like motifs (ADAMTS)-4 and aggrecanase-2/ADAMTS-5 in articular chondrocytes embedded in alginate beads and synovial fibroblasts. In addition, CS-SC and CS-PC overcame the IL-1beta-mediated suppression of the aggrecan core protein mRNA, and suppressed the IL-1beta-enhanced collagenase-3/matrix metalloproteinase (MMP)-13 gene expression in chondrocytes. CS-PC, but not CS-SC effectively recovered the IL-1beta-reduced gene expression of tissue inhibitor of metalloproteinases (TIMP)-3 in chondrocytes, and enhanced the production of TIMP-1 in synovial fibroblasts. It is noteworthy that CS is able to modulate the function of synovial fibroblasts as well as that of chondrocytes. Therefore, CS is very likely to be multifunctional chondroprotective material for degenerative arthritic diseases.

Identification of an active site of EMMPRIN for the augmentation of matrix metalloproteinase-1 and -3 expression in a co-culture of human uterine cervical carcinoma cells and fibroblasts.

OBJECTIVE: Extracellular matrix metalloproteinase inducer (EMMPRIN) is highly expressed on malignant tumor cell surface and accelerates tumor invasion. We previously reported that human uterine cervical carcinoma SKG-II cells exhibit the progression of in-vitro invasiveness by utilizing the enhanced production of matrix metalloproteinase (MMP) in human uterine cervical fibroblasts (HUCF) under an in-vitro co-culture model (Sato T et al., Gynecol Oncol 2004; 92:47-56). The aim of this study was to clarify the active site of EMMPRIN in the augmentation of MMP production in the co-culture of SKG-II cells and HUCF. METHODS: Western and Northern blot analyses were used to examine EMMPRIN and MMP expression in a co-culture of SKG-II cells or EMMPRIN-transfected COS-7 cells and HUCF. A systematic peptide screening method using nine synthetic EMMPRIN peptides was used to identify active site(s) of EMMPRIN for MMP induction. RESULTS: SKG-II cells constitutively expressed 53-kDa EMMPRIN on the cell surface and EMMPRIN production was enhanced under the co-culture. The concomitant augmentation of proMMP-3 production was diminished by adding an EMMPRIN antibody. EMMPRIN-transfected COS-7 cells stimulated HUCF to predominantly augment proMMP-1 and -3 expressions. A systematic peptide screening method revealed that (42)SLNDSATEVTGHRWLK(57) in the first loop domain of EMMPRIN participated in the augmentation of proMMP-1 production. CONCLUSIONS: These results provide a novel mechanism of malignancy of uterine cervical carcinoma, in that the augmentation of EMMPRIN expression by tumor-stromal cell interaction progresses tumor invasion along with the increase of MMP expression via an active site of EMMPRIN, (42)SLNDSATEVTGHRWLK(57).

Nobiletin, a citrus polymethoxy flavonoid, suppresses gene expression and production of aggrecanases-1 and -2 in collagen-induced arthritic mice.

Aggrecanase-1/a disintegrin and metalloproteinase with thrombospondin-like motifs (ADAMTS)-4 and aggrecanase-2/ADAMTS-5 have been shown to play crucial roles in cartilage destruction in arthritic diseases, including rheumatoid arthritis and osteoarthritis. In this study, we examined the effects of nobiletin, a citrus polymethoxy flavone, on the expression and production of ADAMTS-4 and -5 in vitro and in vivo. Nobiletin (16-64muM) interfered with the interleukin (IL)-1beta-mediated ADAMTS-4 and -5 mRNA expression in cultured human synovial fibroblasts. Furthermore, intraperitoneal administration of nobiletin (15, 30, and 60mg/kg) also suppressed ADAMTS-4 and -5 mRNA expression in the joint tissues of collagen-induced arthritic (CIA) mice. Immunohistochemical analysis using an antibody against aggrecan neoepitope (NVTEGE(373)) revealed that aggrecanase-mediated degradation of aggrecan in cartilage was effectively inhibited by nobiletin. These results provide novel evidence that nobiletin effectively interferes with gene expression of ADAMTS-4 and -5, and thereby prevents cartilage destruction in CIA mice.

A citrus polymethoxyflavonoid, nobiletin, is a novel MEK inhibitor that exhibits antitumor metastasis in human fibrosarcoma HT-1080 cells.

The activation of mitogen-activated protein/extracellular signal-regulated kinase (MEK) is well known to be associated with tumor invasion and metastasis. We previously reported that a polymethoxyflavonoid, nobiletin (5,6,7,8,3',4'-hexamethoxyflavone), derived from Citrus depressa (Hayata), inhibits the phosphorylation of MEK and thereby suppresses matrix metalloproteinase (MMP) expression in a tumor-metastasis stimulator, 12-O-tetradecanoyl phorbol 13-acetate (TPA)-stimulated human fibrosarcoma HT-1080 cells [Mol. Cancer Ther. 3 (2004) 839-847]. In the present study, we investigated whether or not nobiletin might directly influence MEK activity to exhibit the antitumor metastatic activity in vitro. MEK kinase assay using myelin basic protein (MBP) revealed that TPA-augmented MEK activity in HT-1080 cells and that the augmented MEK activity was diminished by nobiletin treatment. In addition, the decrease in MEK activity caused by nobiletin was found to inhibit the phosphorylation of extracellular regulated kinases (ERK), a downstream signaling factor for MEK. Furthermore, when an immunoprecipitated active MEK was incubated with nobiletin under cell-free conditions, nobiletin was found to inhibit the MEK-mediated MBP phosphorylation. In contrast, other citrus polymethoxyflavonoids such as 3-hydroxy-5,6,7,8,3',4'-hexamethoxyflavone (natsudaidain) and 3,5,6,7,8,3',4'-heptamethoxyflavone, did not directly inhibit MEK activity. Moreover, natsudaidain and 3,5,6,7,8,3',4'-heptamethoxyflavone exhibited no or less inhibitory effect than nobiletin on the proMMP-9/progelatinase B production in HT-1080 cells. Therefore, these results provide novel evidence that nobiletin directly inhibits MEK activity and decreases the sequential phosphorylation of ERK, exhibiting the antitumor metastatic activity by suppressing MMP expression in HT-1080 cells.

Triptolide, a diterpenoid triepoxide, suppresses inflammation and cartilage destruction in collagen-induced arthritis mice.

Chinese herbal remedy Tripterygium wilfordii Hook. f. (TWHF) has been reported to be therapeutically efficacious in the treatment of rheumatoid arthritis (RA), but its in vivo actions have not been clarified. The purpose of this study was to investigate the effects of triptolide, a diterpenoid triepoxide extracted from TWHF, on inflammation and cartilage destruction in collagen-induced arthritis (CIA) model mice. Histological examination demonstrated that triptolide significantly reduced the inflammatory responses and cartilage damage in the joint tissues. Interestingly, triptolide interfered with CIA-augmented expression of matrix metalloproteinases-13 and -3, which are considered to be key enzymes in the pathological destruction of cartilage, and simultaneously augmented CIA-reduced tissue inhibitors of metalloproteinases-1 and -2 expression in the joints. Moreover, triptolide inhibited prostaglandin E(2) production via selective suppression of the production and gene expression of cyclooxygenase (COX)-2, but not COX-1. The levels of interleukin (IL)-1beta, tumor necrosis factor alpha and IL-6 were also decreased by triptolide in the joint tissues and sera as well as the suppression of CIA-mediated expression of their mRNAs in the joints. In addition, triptolide treatment in vivo was able to reduce an abundance of nuclear factor-kappaB, the transcriptional factor closely related to the inflammatory process, in articular cartilage and synovium in CIA mice. These results suggest that triptolide exerts novel chondroprotective and anti-inflammatory effects on RA, and the therapeutic action of TWHF on RA is, in part, due to the triptolide activities.

Suppressive effect of taurine on platelet-derived growth factor (PDGF) BB-induced c-fos and c-jun mRNA expressions through extracellular signal-regulated kinase (ERK) in mesenchymal cell lines.

Platelet-derived growth factor (PDGF) plays an important role in the pathogenic course of atherosclerosis, pulmonary fibrosis, and glomerulonephritis, and increased activity of the PDGF signaling pathway has been implicated as a contributing factor in the progression of the diseases. Taurine may be a prophylactic amino acid for atherosclerosis not only by decreasing plasma cholesterol level, but also by inhibiting the cell proliferation-signaling pathway. To elucidate how taurine affects the signaling pathway, we investigated the effect of taurine on the expression of immediate-early genes and activation of mitogen-activated protein kinases (MAPKs) in NIH/3T3 cells as standard mesenchymal cells. Taurine inhibited PDGF-BB-induced c-fos and c-jun mRNA expressions dose-dependently, although structural analogues of taurine did not. Taurine decreased the PDGF-induced p44/p42 ERK (extracellular signal-regulated kinase) phosphorylation state dose-dependently, although no phosphorylation was observed on JNK/SAPK (c-Jun N-terminal kinase/stress-activated protein kinase) and p38 MAPK. Further, PDGF-BB-induced tyrosine phosphorylation of the PDGF-beta receptor was not influenced by treatment with taurine, indicating that taurine never affects ligand-receptor interaction, and may act downstream of the PDGF receptor. Thus, the inhibitory mechanism of taurine on PDGF-induced c-fos and c-jun mRNA expressions may depend on the p44/p42 ERK pathway, but not on PDGF-beta receptor tyrosine phosphorylation, JNK/SAPK or p38 MAPK pathway. These results suggest that taurine may suppress the cell proliferation-signaling pathway through the inhibition of ERK activity and immediate-early gene expression.

An antiprogesterone, onapristone, enhances the gene expression of promatrix metalloproteinase 3/prostromelysin-1 in the uterine cervix of pregnant rabbit.

Using a progesterone receptor antagonist, onapristone/ZK 98.299, we examined the in-vivo effects of progesterone on the function of uterine cervix during pregnancy. Onapristone was intravenously administered to pregnant rabbits on day 20 post coitum. After 24 h, the antiprogesterone increased the wet weight of the uterine cervix and decreased the DNA concentration in the cervix. In-situ hybridization also indicated that antiprogesterone augmented the expression of matrix metalloproteinase (MMP)-3/stromelysin-1 mRNA in the uterine cervix. These changes are very similar to those observed and reported thus far in ripened and dilated uterine cervix. These results suggest that during pregnancy, progesterone closely participates in the maintenance of the function of uterine cervix by preventing the production of MMPs and thereby destruction of extracellular matrix, and thus add support to the theory that antiprogesterone has the potential to accelerate for the uterine cervical ripening and dilatation.