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991.
OBJECTIVE: The CXCR4/CXCL12 axis appears crucial in the metastasis of bladder cancer. Our aim was to evaluate the potency of the CXCR4 antagonist, 4F-benzoyl-TE14011 (4F-bTE), as an anti-metastatic drug in this disease. In this study, we assessed the ability of 4F-bTE to inhibit tumor cell motility, invasion through extracellular matrix (ECM), matrix metalloproteinase (MMP) secretion and cytoskeletal responses to chemokine. METHODS: To assess the degree to which cells could migrate and invade ECM under various conditions, we used TCCSUP bladder cancer cells in a Boyden chamber system. To monitor actin polymerization, we stained cells on chamber slides with AlexaFluor 594 phalloidin. To measure matrix-metalloproteinase-2 and -9 (MMP) activity, we used gelatin zymography. To assess the effects of the CXCR4 antagonist 4F-bTE on each of the above parameters, we exposed bladder cancer cells either to chemokine CXCL12, alone, or to both CXCL12 and 4F-bTE. We also monitored cells for apoptotic and necrotic changes during drug treatment. RESULTS: The CXCR4 antagonist 4F-bTE markedly decreased CXCL12-induced bladder cancer cell migration and ECM invasion in Boyden chamber assays. The antagonist also blocked chemokine-induced actin polymerization as well as the induction of MMP-2 and MMP-9 in these cells. CONCLUSION: The CXCR4 antagonist 4F-bTE has the potential to inhibit expression of the metastatic phenotype and may provide therapeutic value to patients. 相似文献
992.
OBJECTIVES: The objective of the present study was to investigate the effect of vaginally and orally administered misoprostol on the local cervical inflammatory response. METHODS: Healthy women with a normal intrauterine pregnancy between 8 and 12 weeks of gestation presenting for an elective termination of pregnancy by vacuum aspiration were recruited into a cohort study with a control and a treatment group. In the treatment group, the women were randomized to misoprostol, 400 mug, given either orally or vaginally 3 h before surgery. Immunohistochemistry staining of CD45, CD68, MMP 8, MMP 9, TIMP 1 and TIMP 2 were assessed in cervical biopsies obtained directly prior to mechanical cervical dilatation and vacuum aspiration. RESULTS: In the treatment group, there was a greater amount of CD45-positive cells in the subepithelium region of the cervix compared to the control group. The staining of CD68 was similar in both groups. The immunostaining of MMP 8 and MMP 9 was greater in the treatment group, while the expression of TIMP 1 and TIMP 2 did not differ between control and treatment groups. CONCLUSIONS: Compared to untreated controls, treatment with misoprostol was associated with a greater expression of inflammatory cells. It could be hypothesized that administration of misoprostol mimics the cervical ripening at term pregnancy by a possible influx and activation of inflammatory cells, which increases MMP 8 and MMP 9 and thereby leads to the degradation of collagen and cervical softening. 相似文献
993.
994.
BACKGROUND: Laminin-5 (Ln-5) cleaved by membrane type 1-matrix metalloproteinase (MT1-MMP) enhances the migration of tumor cells. The purpose of this study was to determine whether or not enhanced expression of both Ln-5 and MT1-MMP was associated with lymph node metastasis in patients with T1 and T2 squamous cell carcinoma (SCC) of the tongue and floor of the mouth. METHODS: By use of biopsy specimens of primary tumors from 57 patients, intratumoral expression of Ln-5 and MT1-MMP was evaluated immunohistochemically and its association with node metastasis analyzed. RESULTS: The tumors were categorized into three groups: Ln-5 focal type/MT1-MMP (-) (group I, n = 14), Ln-5 focal type/ MT1-MMP (+) and Ln-5 diffuse type/MT1-MMP (-) (group II, n = 16), and Ln-5 diffuse type/MT1-MMP (+) (group III, n = 27). The incidence of node metastasis (initial and latent metastases) was two of 14 (14.3%), five of 16 (31.3%), and 15 of 27 (55.6%) in groups I, II, and III, respectively. Multivariate analysis identified tumor thickness (odds ratio, 4.751; p = .0152) and Ln-5/ MT1-MMP expression (odds ratio, 3.795, p = .0304) as independent factors of node metastasis. Moreover, in 35 patients with N0 disease, Ln-5/MT1-MMP expression was the only parameter associated with latent node metastasis (odds ratio, 12.800, p = .0247). CONCLUSION: These results suggest that immunohistochemical evaluation of Ln-5 and MT1-MMP expression is useful for identifying patients with T1 and T2 SCC of the tongue and floor of the mouth who should be treated with elective neck dissection. 相似文献
995.
Matrix metalloproteases (MMPs) are a collection of enzymes capable of cleaving extracellular matrix components, growth factors, and cell-surface receptors. MMPs modulate most aspects of tumorigenesis and are highly expressed in cancer compared with normal tissues. Preclinical studies have demonstrated that head and neck squamous cell carcinomas (HNSCCs) express high levels of MMPs in vivo and that inhibition of these enzymes in vitro and in mouse models decreases invasion and metastasis. However, the clinical trials for MMP inhibitors have failed to demonstrate a significant survival advantage in most cancers. The disparity between preclinical and clinical studies has led to the reevaluation of how MMP functions in cancer and the design of clinical trials for molecularly targeted agents. Mouse model data and analysis of HNSCC tumor specimens suggests that membrane type-1 MMP (MT1-MMP) may be a critical enzyme in tumor cell invasion and survival in vivo. This accumulated data provide evidence for development of selective MT1-MMP inhibitors as therapy in HNSCC. 相似文献
996.
Schisandrin B enhances doxorubicin-induced apoptosis of cancer cells but not normal cells 总被引:8,自引:0,他引:8
The dose-dependent cardiotoxicities of doxorubicin (DOX) significantly limits its anti-cancer efficacies. One of the ways to augment the efficacies of DOX at a relatively low cumulative dose is to use a chemical sensitizer. Here, we demonstrated that schisandrin B (Sch B) significantly enhanced DOX-induced apoptosis of SMMC7721, a human hepatic carcinoma cell line, and of MCF-7, a human breast cancer cell line. This enhancement was irrelevant to the action of Sch B on P-glycoprotein or other drug-transporters, but associated with the activation of caspase-9 rather than caspase-8. The loss of mitochondria membrane potential was observed when cells were treated with DOX and Sch B combined. On the other hand, at the same experimental conditions, Sch B did not enhance the DOX-induced apoptosis of primary rat cardiomyocytes and primary human fibroblasts. Therefore, it is speculative that Sch B may bring benefit to clinical chemotherapy by reducing significantly the cumulative doses of DOX and its associated cardiotoxicities. 相似文献
997.
Inflammation and cancer: how hot is the link? 总被引:21,自引:0,他引:21
998.
Bonfil RD Sabbota A Nabha S Bernardo MM Dong Z Meng H Yamamoto H Chinni SR Lim IT Chang M Filetti LC Mobashery S Cher ML Fridman R 《International journal of cancer. Journal international du cancer》2006,118(11):2721-2726
Metastasis to the bone is a major clinical complication in patients with prostate cancer (PC). However, therapeutic options for treatment of PC bone metastasis are limited. Gelatinases are members of the matrix metalloproteinase (MMP) family and have been shown to play a key role in PC metastasis. Herein, we investigated the effect of SB-3CT, a covalent mechanism-based MMP inhibitor with high selectivity for gelatinases, in an experimental model of PC bone metastases. Intraperitoneal (i.p.) treatment with SB-3CT (50 mg/kg) inhibited intraosseous growth of human PC3 cells within the marrow of human fetal femur fragments previously implanted in SCID mice, as demonstrated by histomorphometry and Ki-67 immunohistochemistry. The anti-osteolytic effect of SB-3CT was confirmed by radiographic images. Treatment with SB-3CT also reduced intratumoral vascular density and bone degradation in the PC3 bone tumors. A direct inhibition of bone marrow endothelial cell invasion and tubule formation in Matrigel by SB-3CT in vitro was also demonstrated. The use of the highly selective gelatinase inhibitors holds the promise of effective intervention of metastases of PC to the bone. 相似文献
999.
Sillanpää SM Anttila MA Voutilainen KA Ropponen KM Sironen RK Saarikoski SV Kosma VM 《International journal of cancer. Journal international du cancer》2006,119(8):1792-1799
We investigated the expression and prognostic significance of matrix metalloproteinase (MMP) -7, its relation to beta-catenin expression and clinicopathological factors in epithelial ovarian cancer. The expression of MMP-7 was analyzed immunohistochemically in a series of 284 primary epithelial ovarian cancers, their 36 metastases and 8 normal ovaries. In cancers with endometrioid histology, a high percentage area of MMP-7 expression and an intense MMP-7 signal was significantly associated with nuclear positivity of beta-catenin in cancer cells (p = 0.003, chi2 = 8.853 and p = 0.030, chi2 = 4.713, respectively). In all tumors and nonendometrioid subgroup, a low percentage area of MMP-7 positive tumor cells was significantly correlated with a high histological grade of the tumor (p = 0.003 and 0.005, respectively), in all tumors also with advanced stage of the tumor (p = 0.002) and large primary residual tumor (p = 0.005). A 10-year disease-related survival (DRS) was significantly better when the percentage area of MMP-7 expression in cancer cells was high, when compared to low (p = 0.0008). A high percentage area of intense MMP-7 signal in cancer cells predicted a significantly more favorable DRS and recurrence-free survival (RFS) (p = 0.0003 and 0.0052, respectively). In multivariate analysis, a high percentage area of intense MMP-7 signal in tumor cells was an independent prognostic factor, predicting favorable DRS and RFS. The present study showed that intense MMP-7 signal in tumor cells is an independent prognostic factor predicting better survival in epithelial ovarian cancer. 相似文献
1000.
BACKGROUND AND OBJECTIVES: In this study, we identified matrix metalloproteinase (MMP)-2 and 9 expression in exophytic papilloma (EP), inverted papilloma (IP) with dysplasia, IP with carcinoma, and invasive squamous cell carcinoma (SCC). We also compared the presence of MMP-2 and 9 with human papilloma virus (HPV) infection. METHODS: The nasal tissue were stained with monoclonal antibodies to MMP-2 and 9. The results were analyzed using quantitative immunohistochemical analysis. In situ hybridization studies for HPV DNA for 6/11, 16/18, and 31/33 were also performed on the tissue. RESULTS: Significant increase of MMP-2 and 9 were observed in IP with moderate and severe dysplasia, IP with carcinoma, and invasive SCC compared to control nasal mucosa. Among IP, HPV 6/11-positive was present in 41% and HPV 16/18-positive was present in 31%. In HPV 6/11 and 16/18-positive IP, significant increase of MMP-2 and 9 were observed. CONCLUSIONS: Precancerous lesions of IP exhibited elevated levels of MMP-2 and 9 and these expression may be associated with early events in IP carcinogenesis. HPV infection would be an early event in a multistep process of malignant formation of IP. 相似文献