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Functional consequences of WNT3/Frizzled7-mediated signaling in non-transformed hepatic cells.

ABSTRACT: We have previously demonstrated that WNT3 and Frizzled7 (FZD7) expression levelswere upregulated in hepatocellular carcinoma (HCC) and that they directly interact to activate the canonical Wnt/?-catenin pathway in HCC cell lines. In this study, we investigated the functional consequences of WNT3 and FZD7 expression levels in non-transformed hepatic cells to address the question of whether WNT3/FZD7-mediated signal transduction could be involved in cellular transformation. After stable transfection of WNT3 and FZD7, the activation of the Wnt/?-catenin pathway was confirmed by western blot, immunostaining and quantitative real-time reverse transcriptase-PCR (qRT-PCR) analysis in two non-transformed hepatocyte-derived cell lines. In vitro characteristics of the malignant phenotype were measured, including cell proliferation, migration, invasion and anchorage-independent growth in soft agar. Stable expression of WNT3 and FZD7 in the two cell lines led to cellular accumulation of ?-catenin and expression of downstream target genes activated by this pathway. In the stable WNT3/FZD7-expressing clones, hepatic cell proliferation, migration, invasion as well as soft agar colony formation were enhanced compared with the non-transformed control cells. The epithelial-mesenchymal transition (EMT) factors, Twist, Snail and Vimentin, were increased in cells expressing WNT3 and FZD7. However, the WNT3/FZD7-expressing cells did not form tumors in vivo. We conclude that activation of the WNT3/FZD7 canonical pathway has a role in the early stages of hepatocarcinogenesis by promoting the acquisition of a malignant phenotype with features of EMT.

SUBMITTER: Nambotin SB

PROVIDER: S-EPMC3503290 | biostudies-other | 2012 Oct

REPOSITORIES: biostudies-other

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Functional consequences of WNT3/Frizzled7-mediated signaling in non-transformed hepatic cells.

Nambotin S B SB Tomimaru Y Y Merle P P Wands J R JR Kim M M

Oncogenesis 20121022

We have previously demonstrated that WNT3 and Frizzled7 (FZD7) expression levelswere upregulated in hepatocellular carcinoma (HCC) and that they directly interact to activate the canonical Wnt/β-catenin pathway in HCC cell lines. In this study, we investigated the functional consequences of WNT3 and FZD7 expression levels in non-transformed hepatic cells to address the question of whether WNT3/FZD7-mediated signal transduction could be involved in cellular transformation. After stable transfecti ...[more]

PMID: 23552403

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Dataset Information

Functional consequences of WNT3/Frizzled7-mediated signaling in non-transformed hepatic cells.

Publications

Functional consequences of WNT3/Frizzled7-mediated signaling in non-transformed hepatic cells.

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