Caffeine suppresses the progression of human glioblastoma via cathepsin B and MAPK signaling pathway.

Glioblastoma has aggressive proliferative and invasive properties. We investigated the effect of caffeine on the invasion and the anti-cancer effect in human glioblastomas. Caffeine reduced the invasion in U-87MG, GBM8401 and LN229 cells. Caffeine decreased mRNA, protein expression, and activity of cathepsin B. Besides, mRNA and protein expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) was upregulated by caffeine treatment, whereas matrix metalloproteinase-2 (MMP-2) was downregulated. The expression of Ki67, p-p38, phospforylated extracellular regulated protein kinases (p-ERK), and membranous integrin ß1 and ß3 was decreased by caffeine. The Rho-associated protein kinase (ROCK) inhibitor, Y27632, blocked the caffeine-mediated reduction of cathepsin B, phosphorylated focal adhesion kinase (p-FAK), and p-ERK, and invasion. Moreover, caffeine decreased the tumor size, cathepsin B and Ki67 expression in animal model. Caffeine reduced the invasion of glioma cells through ROCK-cathepsin B/FAK/ERK signaling pathway and tumor growth in orthotopic xenograft animal model, supporting the anti-cancer potential in glioma therapy.

First evidence that Ecklonia cava-derived dieckol attenuates MCF-7 human breast carcinoma cell migration.

We investigated the effect of Ecklonia cava (E. cava)-derived dieckol on movement behavior and the expression of migration-related genes in MCF-7 human breast cancer cell. Phlorotannins (e.g., dieckol, 6,6'-biecko, and 2,7″-phloroglucinol-6,6'-bieckol) were purified from E. cava by using centrifugal partition chromatography. Among the phlorotannins, we found that dieckol inhibited breast cancer cell the most and was selected for further study. Radius™-well was used to assess cell migration, and dieckol (1-100 µM) was found to suppress breast cancer cell movement. Metastasis-related gene expressions were evaluated by RT-PCR and Western blot analysis. In addition, dieckol inhibited the expression of migration-related genes such as matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF). On the other hand, it stimulated the expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. These results suggest that dieckol exerts anti-breast cancer activity via the regulation of the expressions of metastasis-related genes, and this is the first report on the anti-breast cancer effect of dieckol.

Selaginella tamariscina (Beauv.) possesses antimetastatic effects on human osteosarcoma cells by decreasing MMP-2 and MMP-9 secretions via p38 and Akt signaling pathways.

Selaginella tamariscina is a traditional medicinal plant for treatment of some advanced cancers in the Orient. However, the effect of S. tamariscina on metastasis of osteosarcoma and the underlying mechanism remain unclear. We tested the hypothesis that S. tamariscina suppresses cellular motility, invasion and migration and also investigated its signaling pathways. This study demonstrates that S. tamariscina, at a range of concentrations (from 0 to 50 µg/mL), concentration-dependently inhibited the migration/invasion capacities of three osteosarcoma cell lines without cytotoxic effects. Zymographic and western blot analyses revealed that S. tamariscina inhibited the matrix metalloproteinase (MMP)-2 and MMP-9 enzyme activity, as well as protein expression. Western blot analysis also showed that S. tamariscina inhibits phosphorylation of p38 and Akt. Furthermore, SB203580 (p38 inhibitor) and LY294002 (PI3K inhibitor) showed the similar effects as S. tamariscina in U2OS cells. In conclusion, S. tamariscina possesses an antimetastatic activity in osteosarcoma cells by down-regulating MMP-2 and MMP-9 secretions and increasing TIMP-1 and TIMP-2 expressions through p38 and Akt-dependent pathways. S. tamariscina may be a powerful candidate to develop a preventive agent for osteosarcoma metastasis.

Molecular mechanism depressing PMA-induced invasive behaviors in human lung adenocarcinoma cells by cis- and trans-cinnamic acid.

Dietary polyphenols have been reported as an effective phytochemical for health protection and cinnamic acid (CA) is one of the polyphenols that has been demonstrated having chemopreventive potential. It was known that the early and distal metastasis might lead to the high mortality of patients with lung adenocarcinoma. We previously compared and verified the inhibitory effect of cis-CA and trans-CA on phorbol-12-myristate-13-acetate (PMA)-induced invasion of human lung adenocarcinoma A549 cells. The aim of this study was to explore the underlying molecular mechanism. By gelatin zymography and semi-quantitative RT-PCR, the activities and mRNA of MMP-9/MMP-2 exerted a significantly (p<.05) dose-dependent reduction by treating with cis-CA and trans-CA. Western blots further showed that the cis-CA- and trans-CA-inhibited MMPs might partly through modulating TIMP-1 and the PAI-2-regulated uPA activity. In molecular level, the AP-1 and NF-κB as well as the downstream of the MAPK pathway might be involved in cis-CA- and trans-CA-inhibited MMPs expression. This study disclosed the molecular mechanism underlying the anti-invasive activity of cis-CA and trans-CA and concluded the cis- and trans-form of CA should be a safe and potential agent to prevent lung tumor cells from metastasizing.

Up-regulation of TIMP-1 by genipin inhibits MMP-2 activities and suppresses the metastatic potential of human hepatocellular carcinoma.

AIM OF THE STUDY: Hepatocellular carcinoma is one of the most malignant human cancers with high metastatic potential. The aim of this study is to investigate the anti-metastatic effect of genipin and its underlying mechanism. EXPERIMENTAL APPROACH: The anti-metastatic potential of genipin was evaluated by both cell and animal model. Wound healing and invasion chamber assays were introduced to examine the anti-migration and anti-invasion action of genipin in human hepatocellular carcinoma cell HepG2 and MHCC97L; orthotopical implantation model was used for in vivo evaluation. Gelatin Zymography, Immunoblotting, quantitative real-time polymerase chain reaction and ELISA assays were used to study the mechanisms underlying genipin's anti-metastatic effect. KEY RESULTS: Genipin suppresses the motility and invasiveness of HepG2 and MHCC97L at non-toxic doses, which may be correlated to the inhibition of genipin on MMP-2 activities in the cells. No significant reduced expression of MMP-2 was observed either at mRNA or at protein level. Furthermore, genipin could specifically up-regulate the expression of TIMP-1, the endogenous inhibitor of MMP-2 activities. Silencing of TIMP-1 by RNA interference abolishes genipin's anti-metastaic effect. Activation of p38 MAPK signaling was observed in genipin-treated cells, which is responsible for the TIMP-1 overexpression and MMP-2 inhibition. Presence of SB202190, the p38 MAPK inhibitor, attenuates the anti-metastatic potential of genipin in hepatocellular carcinoma. Orthotopical implantation model showed that genipin could suppress the intrahepatic metastatic as well as tumor expansion in liver without exhibiting potent toxicity. CONCLUSION: Our findings demonstrated the potential of genipin in suppressing hepatocellular carcinoma metastasis, and p38/TIMP-1/MMP-2 pathway may be involved as the key mechanism of its anti-metastasis effect.

Atorvastatin sensitizes human non-small cell lung carcinomas to carboplatin via suppression of AKT activation and upregulation of TIMP-1.

Platinum-based chemotherapy is the standard treatment for advanced non-small-cell lung carcinomas (NSCLCs). However, the antitumoral effect of carboplatin displays unsatisfactory in NSCLCs treatment due to the AKT pathway-mediated carboplatin insensitive in NSCLCs treatment. Previous studies have shown that statins have antitumor activity, but it is unknown whether atorvastatin can reverse carboplatin resistance in lung cancer. Treatment with atorvastatin and carboplatin reduced the growth of xenograft A549 tumors in nude mice and enhanced the survival rate compared with carboplatin alone. Atorvastatin in combination with carboplatin had stronger effects on growth inhibition and apoptosis of NSCLC than either agent used individually. Carboplatin conferred anti-invasive effect in NSCLC cells mainly through inhibition of AKT activity and resultant upregulation of TIMP-1. However, the inhibitory effect on AKT activity by carboplatin was short-term. Additional atorvastatin administration resulted in synergistic inhibition of NSCLC cell invasion and stimulation of TIMP-1 expression with carboplatin through stronger and persistent inhibition of AKT activity both in vivo and in vitro. The synergy of atorvastatin and carboplatin was confirmed using another human lung carcinoma cell line (H1299). Altogether, our data demonstrate that atorvastatin may overcome carboplatin resistance in lung cancer by suppressing AKT activity and upregulating TIMP-1. A combination of atorvastatin and carboplatin may be an effective strategy in clinical therapy against NSCLCs.

Regulation of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) by non-steroidal anti-inflammatory drugs (NSAIDs).

NSAIDs are known to be inhibitors of cyclooxygenase-2 (COX-2) accounting for their anti-inflammatory and anti-tumor activities. However, the anti-tumor activity cannot be totally attributed to their COX-2 inhibitory activity as these drugs can also inhibit the growth and tumor formation of COX-2-null cell lines. Several potential targets aside from COX-2 for NSAIDs have been proposed. 15-Hydroxyprostaglandin dehydrogenase (15-PGDH), a key prostaglandin catabolic enzyme, was recently shown to be a tumor suppressor. Effects of NSAIDs on 15-PGDH expression were therefore studied. Flurbiprofen, indomethacin and other NSAIDs stimulated 15-PGDH activity in colon cancer HT29 cells as well as in lung cancer A549 cells and glioblastoma T98G cells. (R)-flurbiprofen and sulindac sulfone, COX-2 inactive analogs, also stimulated 15-PGDH activity indicating induction of 15-PGDH is independent of COX-2 inhibition. Stimulation of 15-PGDH expression and activity by NSAIDs was examined in detail in colon cancer HT29 cells using flurbiprofen as a stimulant. Flurbiprofen stimulated 15-PGDH expression and activity by increasing transcription and translation and by decreasing the turnover of 15-PGDH. Mechanism of stimulation of 15-PGDH expression is not clear. Protease(s) involved in the turnover of 15-PGDH remains to be identified. However, flurbiprofen down-regulated matrix metalloproteinase-9 (MMP-9) which was shown to degrade 15-PGDH, but up-regulated tissue inhibitor of metalloproteinase-1 (TIMP-1), an inhibitor of MMP-9 contributing further to a slower turnover of 15-PGDH. Taken together, NSAIDs may up-regulate 15-PGDH by increasing the protein expression as well as decreasing the turnover of 15-PGDH in cancer cells.

Effect of 1, 25 dihydroxyvitamin D(3) on matrix metalloproteinases MMP-7, MMP-9 and the inhibitor TIMP-1 in pulmonary tuberculosis.

Matrix metalloproteinases (MMPs) play a vital role in the pathogenesis of several inflammatory diseases including tuberculosis through tissue remodeling. 1, 25(OH)(2)D(3) has several well recognized biological functions including suppression of MMP production. The influence of 1, 25(OH)(2)D(3) on MMP-7, MMP-9 and tissue inhibitor of metalloproteinase-1 (TIMP-1), production was studied in 43 pulmonary tuberculosis (PTB) patients and 44 healthy controls (HC). Peripheral blood mononuclear cells (PBMCs) were cultured with culture filtrate antigen (CFA) of Mycobacterium tuberculosis (MTB) and live MTB with or without 1, 25(OH)(2)D(3) (10(-7) M) for 48 h and the culture supernatants were assayed for MMP-7, MMP-9, TIMP-1 and cytokines IFN-gamma and TNF-alpha using ELISA. In HC and PTB, the levels of MMP-7, MMP-9 and TIMP-1 were not altered by CFA and live MTB stimulation in both groups. However, a significant decrease in the spontaneous production of MMP-7 (p=0.007), and an increase in MMP-9 (p=0.07) and TIMP-1 (p=0.0001) were observed in PTB patients as compared to HC. Vitamin D(3) significantly reduced the MMP-7 (p=0.0001) and MMP-9 (p=0.0001) and increased the TIMP-1 (p=0.005) level in antigen stimulated and unstimulated cultures of PTB as compared to HC. A significant positive correlation between MMP-9 and IFN-gamma was observed in unstimulated cultures of both HC (p=0.05) and PTB patients (p=0.0007). The present study suggests that 1, 25(OH)(2)D(3) suppresses the production of MMPs and enhances the level of TIMP-1 in tuberculosis. The present study suggests that 1, 25(OH)(2)D(3) may probably play an important role in the pathological process in tuberculosis by downregulating the levels of MMPs and upregulating the levels of TIMPs.

Effects of bisphosphonate on matrix metalloproteinase enzymes in human periodontal ligament cells.

BACKGROUND: The host response is a critical component in the pathogenesis of periodontitis. In fact, the clinical benefits associated with regulating the host response have been demonstrated in studies using several different classes of drugs. Biophosphates are one host-modulating class of drugs that has demonstrated this ability. These drugs are clinically effective at reducing bone resorption and have shown the ability to inhibit host degradative enzymes, specifically the matrix metalloproteinases (MMPs). Therefore, the purpose of this study was to investigate the regulatory effects of a bisphosphonate, tiludronate, on MMP levels and activity in human periodontal cells. METHODS: MMP-1 and MMP-3 were assessed in cultured human periodontal ligament cells treated with a bisphosphonate, tiludronate. Reverse transcription-polymerase chain reaction was used to identify mRNA levels for both enzymes, and also for tissue inhibitors (TIMP-1). Enzyme immunoassay (EIA) and immunocytochemistry were used to assess MMP proteins in these cell cultures. Enzyme activity was assessed using FITC-conjugated substrates and quantitated using spectrophotofluorometry. RESULTS: Tiludronate significantly inhibited both MMP-1 and MMP-3 activity in a concentration-dependent manner. A maximal reduction in activity of 35% was achieved for each of the enzymes at a 10(-4) M concentration. Tiludronate did not have a significant effect on the mRNA levels for MMP-1, MMP-3, or TIMP-1. Similarly, there were no effects noted for either MMP-1 or MMP-3 on the protein level. CONCLUSIONS: This study demonstrates an inhibitory effect of tiludronate on the activity of both MMP-1 and MMP-3. These effects appear to occur without altering either mRNA or protein levels for these enzymes, supporting a possible mechanism of action that involves the ability of bisphosphonates to chelate cations from the MMPs. Furthermore, these results support the continued investigation of these drugs as potential therapeutic agents in periodontal disease.