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MicroRNA-22 regulates hypoxia signaling in colon cancer cells.

ABSTRACT: MicroRNAs (MiRNAs) are short, non-coding RNA that regulate a variety of cellular functions by suppressing target protein expression. We hypothesized that a set of microRNA regulate tumor responses to hypoxia by inhibiting components of the hypoxia signaling pathway. We found that miR-22 expression in human colon cancer is lower than in normal colon tissue. We also found that miR-22 controls hypoxia inducible factor 1? (HIF-1?) expression in the HCT116 colon cancer cell line. Over-expression of miR-22 inhibits HIF-1? expression, repressing vascular endothelial growth factor (VEGF) production during hypoxia. Conversely, knockdown of endogenous miR-22 enhances hypoxia induced expression of HIF-1? and VEGF. The conditioned media from cells over-expressing miR-22 contain less VEGF protein than control cells, and also induce less endothelial cell growth and invasion, suggesting miR-22 in adjacent cells influences endothelial cell function. Taken together, our data suggest that miR-22 might have an anti-angiogenic effect in colon cancer.

SUBMITTER: Yamakuchi M

PROVIDER: S-EPMC3100326 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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MicroRNA-22 regulates hypoxia signaling in colon cancer cells.

Yamakuchi Munekazu M Yagi Shusuke S Ito Takashi T Lowenstein Charles J CJ

PloS one 20110523 5

MicroRNAs (MiRNAs) are short, non-coding RNA that regulate a variety of cellular functions by suppressing target protein expression. We hypothesized that a set of microRNA regulate tumor responses to hypoxia by inhibiting components of the hypoxia signaling pathway. We found that miR-22 expression in human colon cancer is lower than in normal colon tissue. We also found that miR-22 controls hypoxia inducible factor 1α (HIF-1α) expression in the HCT116 colon cancer cell line. Over-expression of m ...[more]

PMID: 21629773

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