Oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral cavity. Here, we provide molecular evidence associated with the anti-metastatic effect of silibinin by showing a marked inhibition of the invasion and motility of SCC-4 tongue cancer cells, with 89% and 66.4% of inhibition, respectively, by 100 μM of silibinin. This effect was associated with a reduced expression of MMP-2 and u-PA, together with an enhanced expression of TIMP-2 and PAI-1. Silibinin also exerted an inhibitory effect on the phosphorylation of ERK1/2. Additionally, pre-treatment of SCC-4 cancer cells with 10 and 20 μM of U0126, a specific MEK inhibitor, resulted in a reduced expression of MMP-2 (18.7 and 51.4%) and u-PA (19.2 and 48.9%) concomitantly with a marked inhibition of cell invasion (13.7 and 45.7%). Finally, silibinin was evidenced by its inhibition of the metastasis of Lewis lung carcinoma (LLC) cells in vivo. These results suggested that silibinin can reduce the invasion and metastasis of tumor cells, and such a characteristic may be of great value in the development of a potential cancer therapy.
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References
1.
Agarwal C, Singh RP, Dhanalakshmi S, Tyagi AK, Tecklenburg M, Sclafani RA, Agarwal R -2003-. Silibinin upregulates the expression of cyclin-dependent kinase inhibitors and causes cell cycle arrest and apoptosis in human colon carcinoma HT-29 cells. Oncogene22:8271–8282.
2.
Agarwal R, Katiyar SK, Lundgren DW, Mukhtar H -1994-. Inhibitory effect of silymarin, an anti-hepatotoxic flavonoid, on 12-O-tetradecanoylphorbol-13-acetate-induced epidermal ornithine decarboxylase activity and mRNA in SENCAR mice. Carcinogenesis15:1099–1103.
3.
Azzam HS, Thompson EW -1992-. Collagen-induced activation of the M-r- 72,000 type IV collagenase in normal and malignant human fibroblastoid cells. Cancer Res52:4540–4544.
4.
Canto MT, Devesa SS -2002-. Oral cavity and pharynx cancer incidence rates in the United States, 1975–1998. Oral Oncol38:610–617.
5.
Chen PN, Chu SC, Chiou HL, Kuo WH, Chiang CL, Hsieh YS -2006-. Mulberry anthocyanins, cyanidin 3-rutinoside and cyanidin 3-glucoside, exhibited an inhibitory effect on the migration and invasion of a human lung cancer cell line. Cancer Lett -in press-.
6.
Chu SC, Chiou HL, Chen PN, Yang SF, Hsieh YS -2004-. Silibinin inhibits the invasion of human lung cancer cells via decreased productions of urokinase-plasminogen activator and matrix metalloproteinase-2. Mol Carcinog40:143–149.
7.
Geletu G, Plamadeala P, Gogalniceanu D, Zeilhofer HF, Popescu E, Moscalu M -2004-. [Urokinase-type plasminogen activator -uPA- and its inhibitor—new prognostic factors in oral squamous cell carcinoma]. Rev Med Chir Soc Med Nat Iasi108:79–84.
8.
Kurahara S, Shinohara M, Ikebe T, Nakamura S, Beppu M, Hiraki A, et al. -1999-. Expression of MMPS, MT-MMP, and TIMPs in squamous cell carcinoma of the oral cavity: correlations with tumor invasion and metastasis. Head Neck21:627–638.
9.
Lee YK, So IS, Lee SC, Lee JH, Lee CW, Kim WM, et al. -2005-. Suppression of distant pulmonary metastasis of MDA-MB 435 human breast carcinoma established in mammary fat pads of nude mice by retroviral-mediated TIMP-2 gene transfer. J Gene Med7:145–157.
10.
Lev DC, Onn A, Melinkova VO, Miller C, Stone V, Ruiz M, et al. -2004-. Exposure of melanoma cells to dacarbazine results in enhanced tumor growth and metastasis in vivo. J Clin Oncol22:2092–2100.
11.
Liotta LA, Tryggvason K, Garbisa S, Hart I, Foltz CM, Shafie S -1980-. Metastatic potential correlates with enzymatic degradation of basement membrane collagen. Nature284:67–68.
12.
Maheshwari H, Agarwal R, Patil C, Katare OP -2003-. Preparation and pharmacological evaluation of silibinin liposomes. Arzneimittelforschung53:420–427.
13.
Mallikarjuna G, Dhanalakshmi S, Singh RP, Agarwal C, Agarwal R -2004-. Silibinin protects against photocarcinogenesis via modulation of cell cycle regulators, mitogen-activated protein kinases, and Akt signaling. Cancer Res64:6349–6356.
14.
Myoung H, Hong SP, Yun PY, Lee JH, Kim MJ -2003-. Anti-cancer effect of genistein in oral squamous cell carcinoma with respect to angiogenesis and in vitro invasion. Cancer Sci94:215–220.
15.
Rao JS -2003-. Molecular mechanisms of glioma invasiveness: the role of proteases. Nat Rev Cancer3:489–501.
16.
Sato H, Takino T, Miyamori H -2005-. Roles of membrane-type matrix metalloproteinase-1 in tumor invasion and metastasis. Cancer Sci96:212–217.
17.
Shimada T, Nakamura H, Yamashita K, Kawata R, Murakami Y, Fujimoto N, et al. -2000-. Enhanced production and activation of progelatinase A mediated by membrane-type 1 matrix metalloproteinase in human oral squamous cell carcinomas: implications for lymph node metastasis. Clin Exp Metastasis18:179–188.
18.
Sigounas G, Sallah S, Sigounas VY -2004-. Erythropoietin modulates the anticancer activity of chemotherapeutic drugs in a murine lung cancer model. Cancer Lett214:171–179.
19.
Steele VE, Kelloff GJ, Wilkinson BP, Arnold JT -1990-. Inhibition of transformation in cultured rat tracheal epithelial cells by potential chemopreventive agents. Cancer Res50:2068–2074.
20.
Stetler-Stevenson WG, Aznavoorian S, Liotta LA -1993-. Tumor cell interactions with the extracellular matrix during invasion and metastasis. Annu Rev Cell Biol9:541–573.
21.
Valente P, Fassina G, Melchiori A, Masiello L, Cilli M, Vacca A, et al. -1998-. TIMP-2 over-expression reduces invasion and angiogenesis and protects B16F10 melanoma cells from apoptosis. Int J Cancer75:246–253.
22.
Vihinen P, Ala-aho R, Kahari VM -2005-. Matrix metalloproteinases as therapeutic targets in cancer. Curr Cancer Drug Targets5:203–220.
23.
von Schonfeld J, Weisbrod B, Muller MK -1997-. Silibinin, a plant extract with antioxidant and membrane stabilizing properties, protects exocrine pancreas from cyclosporin A toxicity. Cell Mol Life Sci53:917–920.
24.
Westermarck J, Kahari VM -1999-. Regulation of matrix metallo-proteinase expression in tumor invasion. FASEB J13:781–792.
25.
Whitley BR, Palmieri D, Twerdi CD, Church FC -2004-. Expression of active plasminogen activator inhibitor-1 reduces cell migration and invasion in breast and gynecological cancer cells. Exp Cell Res296:151–162.
26.
Zhang X, Liu Y, Gilcrease MZ, Yuan XH, Clayman GL, Adler-Storthz K, et al. -2002-. A lymph node metastatic mouse model reveals alterations of metastasis-related gene expression in metastatic human oral carcinoma sublines selected from a poorly metastatic parental cell line. Cancer95:1663–1672.
