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A miR-130a-YAP positive feedback loop promotes organ size and tumorigenesis.

Shen S, Guo X, Yan H, Lu Y, Ji X, Li L, Liang T, Zhou D, Feng XH, Zhao JC, Yu J, Gong XG, Zhang L, Zhao B - Cell Res. (2015)

Bottom Line: Organ size determination is one of the most intriguing unsolved mysteries in biology.Here we report that the YAP signaling is sustained through a novel microRNA-dependent positive feedback loop. miR-130a, which is directly induced by YAP, could effectively repress VGLL4, an inhibitor of YAP activity, thereby amplifying the YAP signals.Furthermore, the Drosophila Hippo pathway target bantam functionally mimics miR-130a by repressing the VGLL4 homolog SdBP/Tgi.

View Article: PubMed Central - PubMed

Affiliation: Life Sciences Institute and Innovation Center for Cell Signaling Network Hangzhou, Zhejiang 310058, China.

ABSTRACT
Organ size determination is one of the most intriguing unsolved mysteries in biology. Aberrant activation of the major effector and transcription co-activator YAP in the Hippo pathway causes drastic organ enlargement in development and underlies tumorigenesis in many human cancers. However, how robust YAP activation is achieved during organ size control remains elusive. Here we report that the YAP signaling is sustained through a novel microRNA-dependent positive feedback loop. miR-130a, which is directly induced by YAP, could effectively repress VGLL4, an inhibitor of YAP activity, thereby amplifying the YAP signals. Inhibition of miR-130a reversed liver size enlargement induced by Hippo pathway inactivation and blocked YAP-induced tumorigenesis. Furthermore, the Drosophila Hippo pathway target bantam functionally mimics miR-130a by repressing the VGLL4 homolog SdBP/Tgi. These findings reveal an evolutionarily conserved positive feedback mechanism underlying robustness of the Hippo pathway in size control and tumorigenesis.

No MeSH data available.


Related in: MedlinePlus

miR-130a mediates the oncogenic potential of YAP. (A) YAP-regulated microRNAs. microRNAs regulated by YAP were determined by microRNA microarrays. microRNAs with a P-value of < 0.01 in ectopic YAP-expressing MCF10A cells and a signal of more than 500 in control cells were selected and the heatmap was drawn using Matlab. (B, C) YAP induces miR-130a expression. MicroRNAs were extracted and miR-130a expression levels were determined by quantitative RT-PCR. Experiments were performed in triplicates. * and ** indicate a P-value of < 0.05 and < 0.01, respectively, as calculated by student's t-test. (D) miR-130a plays a role in YAP-induced cell proliferation. Pre-miR-130a or the miR-130a sponge was expressed with YAP-S127A or YAP-5SA in HepG2 stable cells. Cell viability was determined by CellTiter-Blue assay. (E, F) miR-130a in cellular transformation induced by YAP-5SA. Vector (Vec) or YAP-5SA-expressing HepG2 stable cells transfected with negative control (NC) or miR-130a inhibitor (E) or HMLE stable cells infected with empty vector or YAP-5SA with or without pre-miR-130a (F) were cultured in soft agar for 20 days. Colonies were stained with crystal violet, photographed and quantified by ImageJ (details are shown in inserts). (G and H) miR-130a in YAP-induced tumorigenesis in vivo. Nude mice were injected on the two flanks with 6 × 106(G) or 1 × 107(H) HepG2 stable cells. Tumors were dissected after 3 (G) or 4 (H) weeks and were photographed.
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fig1: miR-130a mediates the oncogenic potential of YAP. (A) YAP-regulated microRNAs. microRNAs regulated by YAP were determined by microRNA microarrays. microRNAs with a P-value of < 0.01 in ectopic YAP-expressing MCF10A cells and a signal of more than 500 in control cells were selected and the heatmap was drawn using Matlab. (B, C) YAP induces miR-130a expression. MicroRNAs were extracted and miR-130a expression levels were determined by quantitative RT-PCR. Experiments were performed in triplicates. * and ** indicate a P-value of < 0.05 and < 0.01, respectively, as calculated by student's t-test. (D) miR-130a plays a role in YAP-induced cell proliferation. Pre-miR-130a or the miR-130a sponge was expressed with YAP-S127A or YAP-5SA in HepG2 stable cells. Cell viability was determined by CellTiter-Blue assay. (E, F) miR-130a in cellular transformation induced by YAP-5SA. Vector (Vec) or YAP-5SA-expressing HepG2 stable cells transfected with negative control (NC) or miR-130a inhibitor (E) or HMLE stable cells infected with empty vector or YAP-5SA with or without pre-miR-130a (F) were cultured in soft agar for 20 days. Colonies were stained with crystal violet, photographed and quantified by ImageJ (details are shown in inserts). (G and H) miR-130a in YAP-induced tumorigenesis in vivo. Nude mice were injected on the two flanks with 6 × 106(G) or 1 × 107(H) HepG2 stable cells. Tumors were dissected after 3 (G) or 4 (H) weeks and were photographed.

Mentions: Profiling of Hippo pathway target genes in mammalian cells or tissues has not yet revealed the key mediator of size regulation and tumorigenesis in vivo3,10,12. To examine whether microRNAs may mediate YAP functions we profiled YAP-induced microRNAs in MCF10A cells by microarray (Figure 1A). Validation of the hits showed that miR-130a was one of the best-induced microRNAs by YAP (Figure 1B and Supplementary information, Figure S1A). More importantly, knockdown of endogenous YAP and TAZ substantially reduced pri- and mature miR-130a levels in multiple cell lines (Figure 1C and Supplementary information, Figure S1B).


A miR-130a-YAP positive feedback loop promotes organ size and tumorigenesis.

Shen S, Guo X, Yan H, Lu Y, Ji X, Li L, Liang T, Zhou D, Feng XH, Zhao JC, Yu J, Gong XG, Zhang L, Zhao B - Cell Res. (2015)

miR-130a mediates the oncogenic potential of YAP. (A) YAP-regulated microRNAs. microRNAs regulated by YAP were determined by microRNA microarrays. microRNAs with a P-value of < 0.01 in ectopic YAP-expressing MCF10A cells and a signal of more than 500 in control cells were selected and the heatmap was drawn using Matlab. (B, C) YAP induces miR-130a expression. MicroRNAs were extracted and miR-130a expression levels were determined by quantitative RT-PCR. Experiments were performed in triplicates. * and ** indicate a P-value of < 0.05 and < 0.01, respectively, as calculated by student's t-test. (D) miR-130a plays a role in YAP-induced cell proliferation. Pre-miR-130a or the miR-130a sponge was expressed with YAP-S127A or YAP-5SA in HepG2 stable cells. Cell viability was determined by CellTiter-Blue assay. (E, F) miR-130a in cellular transformation induced by YAP-5SA. Vector (Vec) or YAP-5SA-expressing HepG2 stable cells transfected with negative control (NC) or miR-130a inhibitor (E) or HMLE stable cells infected with empty vector or YAP-5SA with or without pre-miR-130a (F) were cultured in soft agar for 20 days. Colonies were stained with crystal violet, photographed and quantified by ImageJ (details are shown in inserts). (G and H) miR-130a in YAP-induced tumorigenesis in vivo. Nude mice were injected on the two flanks with 6 × 106(G) or 1 × 107(H) HepG2 stable cells. Tumors were dissected after 3 (G) or 4 (H) weeks and were photographed.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4559818&req=5

fig1: miR-130a mediates the oncogenic potential of YAP. (A) YAP-regulated microRNAs. microRNAs regulated by YAP were determined by microRNA microarrays. microRNAs with a P-value of < 0.01 in ectopic YAP-expressing MCF10A cells and a signal of more than 500 in control cells were selected and the heatmap was drawn using Matlab. (B, C) YAP induces miR-130a expression. MicroRNAs were extracted and miR-130a expression levels were determined by quantitative RT-PCR. Experiments were performed in triplicates. * and ** indicate a P-value of < 0.05 and < 0.01, respectively, as calculated by student's t-test. (D) miR-130a plays a role in YAP-induced cell proliferation. Pre-miR-130a or the miR-130a sponge was expressed with YAP-S127A or YAP-5SA in HepG2 stable cells. Cell viability was determined by CellTiter-Blue assay. (E, F) miR-130a in cellular transformation induced by YAP-5SA. Vector (Vec) or YAP-5SA-expressing HepG2 stable cells transfected with negative control (NC) or miR-130a inhibitor (E) or HMLE stable cells infected with empty vector or YAP-5SA with or without pre-miR-130a (F) were cultured in soft agar for 20 days. Colonies were stained with crystal violet, photographed and quantified by ImageJ (details are shown in inserts). (G and H) miR-130a in YAP-induced tumorigenesis in vivo. Nude mice were injected on the two flanks with 6 × 106(G) or 1 × 107(H) HepG2 stable cells. Tumors were dissected after 3 (G) or 4 (H) weeks and were photographed.
Mentions: Profiling of Hippo pathway target genes in mammalian cells or tissues has not yet revealed the key mediator of size regulation and tumorigenesis in vivo3,10,12. To examine whether microRNAs may mediate YAP functions we profiled YAP-induced microRNAs in MCF10A cells by microarray (Figure 1A). Validation of the hits showed that miR-130a was one of the best-induced microRNAs by YAP (Figure 1B and Supplementary information, Figure S1A). More importantly, knockdown of endogenous YAP and TAZ substantially reduced pri- and mature miR-130a levels in multiple cell lines (Figure 1C and Supplementary information, Figure S1B).

Bottom Line: Organ size determination is one of the most intriguing unsolved mysteries in biology.Here we report that the YAP signaling is sustained through a novel microRNA-dependent positive feedback loop. miR-130a, which is directly induced by YAP, could effectively repress VGLL4, an inhibitor of YAP activity, thereby amplifying the YAP signals.Furthermore, the Drosophila Hippo pathway target bantam functionally mimics miR-130a by repressing the VGLL4 homolog SdBP/Tgi.

View Article: PubMed Central - PubMed

Affiliation: Life Sciences Institute and Innovation Center for Cell Signaling Network Hangzhou, Zhejiang 310058, China.

ABSTRACT
Organ size determination is one of the most intriguing unsolved mysteries in biology. Aberrant activation of the major effector and transcription co-activator YAP in the Hippo pathway causes drastic organ enlargement in development and underlies tumorigenesis in many human cancers. However, how robust YAP activation is achieved during organ size control remains elusive. Here we report that the YAP signaling is sustained through a novel microRNA-dependent positive feedback loop. miR-130a, which is directly induced by YAP, could effectively repress VGLL4, an inhibitor of YAP activity, thereby amplifying the YAP signals. Inhibition of miR-130a reversed liver size enlargement induced by Hippo pathway inactivation and blocked YAP-induced tumorigenesis. Furthermore, the Drosophila Hippo pathway target bantam functionally mimics miR-130a by repressing the VGLL4 homolog SdBP/Tgi. These findings reveal an evolutionarily conserved positive feedback mechanism underlying robustness of the Hippo pathway in size control and tumorigenesis.

No MeSH data available.


Related in: MedlinePlus