title: EGCG inhibits growth of human pancreatic tumors orthotopically implanted in Balb C nude mice through modulation of FKHRL1/FOXO3a and neuropilin.
abstract: Human pancreatic cancer is currently one of the fourth leading causes of cancer-related mortality with a 5-year survival rate of less than 5 %. Since pancreatic carcinoma is largely refractory to conventional therapies, there is a strong medical need for the development of novel and innovative cancer preventive strategies. The forkhead transcription factors of the O class (FOXO) play a major role in cell proliferation, angiogenesis, metastasis, and tumorigenesis. The objectives of this study were to examine whether FKHRL1/FOXO3a modulates antitumor activity of (-)-epigallocatechin-3-gallate (EGCG), an active ingredient in green tea, in pancreatic cancer model in vivo. PANC-1 cells were orthotopically implanted into Balb c nude mice and gavaged with EGCG after tumor formation. Cell proliferation and apoptosis were measured by Ki67 and TUNEL staining, respectively. The expression of PI3K, AKT, ERK, and FOXO3a/FKHRL1 and its target genes were measured by the western blot analysis and/or q-RT-PCR. FOXO-DNA binding was measured by gel shift assay. EGCG-treated mice showed significant inhibition in tumor growth which was associated with reduced phosphorylation of ERK, PI3K, AKT, and FKHRL1/FOXO3a, and modulation of FOXO target genes. EGCG induced apoptosis by upregulating Bim and activating caspase-3. EGCG modulated markers of cell cycle (p27/KIP1), angiogenesis (CD31, VEGF, IL-6, IL-8, SEMA3F, and HIF1α), and metastasis (MMP2 and MMP7). The inhibition of VEGF by EGCG was associated with suppression of neuropilin. EGCG inhibited epithelial-mesenchymal transition by upregulating the expression of E-cadherin and inhibiting the expression of N-cadherin and Zeb1. These data suggest that EGCG inhibits pancreatic cancer orthotopic tumor growth, angiogenesis, and metastasis which are associated with inhibition of PI3K/AKT and ERK pathways and activation of FKHRL1/FOXO3a. As a conclusion, EGCG can be used for the prevention and/or treatment of pancreatic cancer.
authors.affiliation: Department of Pathology and Laboratory Medicine, The University of Kansas Cancer Center, The University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA. sshankar@kumc.edu
authors.forename: Sharmila
authors.initials: S
authors.lastname: Shankar
authors.forename: Luke
authors.initials: L
authors.lastname: Marsh
authors.forename: Rakesh K
authors.initials: RK
authors.lastname: Srivastava
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D021441:Carcinoma, Pancreatic Ductal / Q000098:blood supply / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D000071316:Forkhead Box Protein O3; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009389:Neovascularization, Pathologic / Q000517:prevention & control; D039921:Neuropilins / Q000378:metabolism*; D010179:Pancreas / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000098:blood supply / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D047368:Tumor Burden / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D014408:Biomarkers, Tumor; C499517:FOXO3 protein, human; D000071316:Forkhead Box Protein O3; D051858:Forkhead Transcription Factors; D039921:Neuropilins; D018809:Proliferating Cell Nuclear Antigen; D002392:Catechin; C045651:epigallocatechin gallate