title: Galectin-1-mediated tumor invasion and metastasis, up-regulated matrix metalloproteinase expression, and reorganized actin cytoskeletons.
abstract: Galectin-1 (Gal-1) is a beta-galactose-binding lectin; its expression level has been reported to correlate with tumor progression. Gal-1 is highly expressed in the invasive front of primary tumors and in the cancer cells of metastatic lesions in the lymph nodes of patients with oral squamous cell carcinoma. However, the molecular mechanism of Gal-1 in tumor metastasis is not completely clear. We found that increased Gal-1 expression is closely associated with its high levels of invasion in lung adenocarcinoma and oral squamous cell carcinoma cell lines. Knocking down Gal-1 with small interfering RNA in highly invasive cancer cells reduced their invasion levels. Moreover, the invasion ability of poorly invasive cancer cells was significantly increased after Gal-1 overexpression of Gal-1. Mechanism studies revealed that Gal-1 promoted tumor invasion mainly by up-regulating matrix metalloproteinase (MMP)-9 and MMP-2 and by reorganizing actin cytoskeleton. Gal-1 enhanced the activation of Cdc42, a small GTPase and member of the Rho family, thus increasing the number and length of filopodia on tumor cells. Furthermore, Gal-1-overexpressing cells had higher metastatic abilities in tail vein metastasis assays in vivo. We conclude that Gal-1 is involved in tumor invasion and metastasis by increasing MMP expression and reorganizing cytoskeletons in oral cancers and lung adenocarcinoma.
authors.affiliation: Institute of Basic Medical Sciences, National Cheng Kung University College of Medicine, Tainan, Taiwan.
authors.forename: Ming-Heng
authors.initials: MH
authors.lastname: Wu
authors.forename: Tse-Ming
authors.initials: TM
authors.lastname: Hong
authors.forename: Hui-Wen
authors.initials: HW
authors.lastname: Cheng
authors.forename: Szu-Hua
authors.initials: SH
authors.lastname: Pan
authors.forename: Yu-Ray
authors.initials: YR
authors.lastname: Liang
authors.forename: Hsiao-Chin
authors.initials: HC
authors.lastname: Hong
authors.forename: Wei-Fan
authors.initials: WF
authors.lastname: Chiang
authors.forename: Tung-Yiu
authors.initials: TY
authors.lastname: Wong
authors.forename: Dar-Bin
authors.initials: DB
authors.lastname: Shieh
authors.forename: Ai-Li
authors.initials: AL
authors.lastname: Shiau
authors.forename: Ying-Tai
authors.initials: YT
authors.lastname: Jin
authors.forename: Yuh-Ling
authors.initials: YL
authors.lastname: Chen
mesh_terms: D000199:Actins / Q000378:metabolism*; D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D003599:Cytoskeleton / Q000378:metabolism; D037483:Galectin 1 / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D051379:Mice; D009062:Mouth Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D009361:Neoplasm Invasiveness; D009369:Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D034741:RNA, Small Interfering / Q000235:genetics; D015854:Up-Regulation; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D000199:Actins; D037483:Galectin 1; D034741:RNA, Small Interfering; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D020741:rho GTP-Binding Proteins