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ERBB3 is required for metastasis formation of melanoma cells.

Tiwary S, Preziosi M, Rothberg PG, Zeitouni N, Corson N, Xu L - Oncogenesis (2014)

Bottom Line: Consistent with this, the ERBB3 ligand, NRG1, is highly expressed in mouse lungs and induces ERBB3-depdnent phosphorylation of AKT in both MA-2 and 451Lu-R cells in vitro.These findings suggest that ERBB3 may serve as a target for treating metastatic melanomas that are resistant to BIs.In support of this, administration of the pan-ERBB inhibitor, canertinib, significantly suppresses the metastasis formation of BI-resistant melanoma cell lines.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY, USA.

ABSTRACT
Melanoma is curable when it is at an early phase but is lethal once it becomes metastatic. The recent development of BRAF(V600E) inhibitors (BIs) showed great promise in treating metastatic melanoma, but resistance developed quickly in the treated patients, and these inhibitors are not effective on melanomas that express wild-type BRAF. Alternative therapeutic strategies for metastatic melanoma are urgently needed. Here we report that ERBB3, a member of the epidermal growth factor receptor family, is required for the formation of lung metastasis from both the BI-sensitive melanoma cell line, MA-2, and the BI-resistant melanoma cell line, 451Lu-R. Further analyses revealed that ERBB3 does not affect the initial seeding of melanoma cells in lung but is required for their further development into overt metastases, indicating that ERBB3 might be essential for the survival of melanoma cells after they reach the lung. Consistent with this, the ERBB3 ligand, NRG1, is highly expressed in mouse lungs and induces ERBB3-depdnent phosphorylation of AKT in both MA-2 and 451Lu-R cells in vitro. These findings suggest that ERBB3 may serve as a target for treating metastatic melanomas that are resistant to BIs. In support of this, administration of the pan-ERBB inhibitor, canertinib, significantly suppresses the metastasis formation of BI-resistant melanoma cell lines.

No MeSH data available.


Related in: MedlinePlus

ERBB3 affects the survival of MA-2 cells in the lung at 24 h after injections. (a) Schematic presentation of the predicted processes for CTCs (circulating tumor cells) to form overt metastases. (b) Representative images of the mouse lungs at 3, 6, 12 or 24 h after intravenous injections of MA-2(shGFP), MA-2(shERBB3#1) or MA-2(shERBB3#2) cells. Green: metastatic melanoma cells (white arrows). Red: autofluorescence of the lung. Blue: DAPI for nuclei. (c) ERBB3 knockdown did not affect the number of fluorescent cells in the lung at 3, 6 or 12 h after tail vein injections. In all, 2–3 mice were used under each condition. NS: not significant. (d) Twenty-four hours after injections, the number of MA-2 cells in the lung was significantly reduced upon ERBB3 knockdown. **P<0.01; ***P<0.001.
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fig3: ERBB3 affects the survival of MA-2 cells in the lung at 24 h after injections. (a) Schematic presentation of the predicted processes for CTCs (circulating tumor cells) to form overt metastases. (b) Representative images of the mouse lungs at 3, 6, 12 or 24 h after intravenous injections of MA-2(shGFP), MA-2(shERBB3#1) or MA-2(shERBB3#2) cells. Green: metastatic melanoma cells (white arrows). Red: autofluorescence of the lung. Blue: DAPI for nuclei. (c) ERBB3 knockdown did not affect the number of fluorescent cells in the lung at 3, 6 or 12 h after tail vein injections. In all, 2–3 mice were used under each condition. NS: not significant. (d) Twenty-four hours after injections, the number of MA-2 cells in the lung was significantly reduced upon ERBB3 knockdown. **P<0.01; ***P<0.001.

Mentions: The formation of overt metastases from circulating tumor cells is thought to go through several steps (Figure 3a): they need to seed the target tissue (for example, lung), survive and then proliferate into overt metastases. We asked at which step ERBB3 may exert its effects on the metastasis formation of melanoma cells. MA-2 cells expressing control or ERBB3 shRNAs were labeled with 5-chloromethylfluorescein diacetate (CMFDA), an intense green fluorescent Cell Tracker dye, before intravenous injections into NSG mice. Lungs were harvested shortly (3, 6 or 12 h) after injections, sectioned and visualized under microscope (see Materials and methods). Green fluorescent cells were readily detectable in the lungs at all time points (Figure 3b, white arrows). No difference in the cell number was observed between control- and ERBB3-knockdown MA-2 cells (Figure 3c), suggesting that ERBB3 does not affect the initial seeding of MA-2 cells in the lung (Figure 3a; step 1). We then examined whether ERBB3 affects the survival of MA-2 cells in the lung at later time points. Lungs were harvested 24 h after the injections, and the number of green fluorescent cells on each lung section was counted (Figure 3b). A significant reduction of labeled cells was observed when ERBB3 was knocked down (Figure 3d), suggesting that ERBB3 might be required for the survival of MA-2 cells after their seeding in the lung.


ERBB3 is required for metastasis formation of melanoma cells.

Tiwary S, Preziosi M, Rothberg PG, Zeitouni N, Corson N, Xu L - Oncogenesis (2014)

ERBB3 affects the survival of MA-2 cells in the lung at 24 h after injections. (a) Schematic presentation of the predicted processes for CTCs (circulating tumor cells) to form overt metastases. (b) Representative images of the mouse lungs at 3, 6, 12 or 24 h after intravenous injections of MA-2(shGFP), MA-2(shERBB3#1) or MA-2(shERBB3#2) cells. Green: metastatic melanoma cells (white arrows). Red: autofluorescence of the lung. Blue: DAPI for nuclei. (c) ERBB3 knockdown did not affect the number of fluorescent cells in the lung at 3, 6 or 12 h after tail vein injections. In all, 2–3 mice were used under each condition. NS: not significant. (d) Twenty-four hours after injections, the number of MA-2 cells in the lung was significantly reduced upon ERBB3 knockdown. **P<0.01; ***P<0.001.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4150209&req=5

fig3: ERBB3 affects the survival of MA-2 cells in the lung at 24 h after injections. (a) Schematic presentation of the predicted processes for CTCs (circulating tumor cells) to form overt metastases. (b) Representative images of the mouse lungs at 3, 6, 12 or 24 h after intravenous injections of MA-2(shGFP), MA-2(shERBB3#1) or MA-2(shERBB3#2) cells. Green: metastatic melanoma cells (white arrows). Red: autofluorescence of the lung. Blue: DAPI for nuclei. (c) ERBB3 knockdown did not affect the number of fluorescent cells in the lung at 3, 6 or 12 h after tail vein injections. In all, 2–3 mice were used under each condition. NS: not significant. (d) Twenty-four hours after injections, the number of MA-2 cells in the lung was significantly reduced upon ERBB3 knockdown. **P<0.01; ***P<0.001.
Mentions: The formation of overt metastases from circulating tumor cells is thought to go through several steps (Figure 3a): they need to seed the target tissue (for example, lung), survive and then proliferate into overt metastases. We asked at which step ERBB3 may exert its effects on the metastasis formation of melanoma cells. MA-2 cells expressing control or ERBB3 shRNAs were labeled with 5-chloromethylfluorescein diacetate (CMFDA), an intense green fluorescent Cell Tracker dye, before intravenous injections into NSG mice. Lungs were harvested shortly (3, 6 or 12 h) after injections, sectioned and visualized under microscope (see Materials and methods). Green fluorescent cells were readily detectable in the lungs at all time points (Figure 3b, white arrows). No difference in the cell number was observed between control- and ERBB3-knockdown MA-2 cells (Figure 3c), suggesting that ERBB3 does not affect the initial seeding of MA-2 cells in the lung (Figure 3a; step 1). We then examined whether ERBB3 affects the survival of MA-2 cells in the lung at later time points. Lungs were harvested 24 h after the injections, and the number of green fluorescent cells on each lung section was counted (Figure 3b). A significant reduction of labeled cells was observed when ERBB3 was knocked down (Figure 3d), suggesting that ERBB3 might be required for the survival of MA-2 cells after their seeding in the lung.

Bottom Line: Consistent with this, the ERBB3 ligand, NRG1, is highly expressed in mouse lungs and induces ERBB3-depdnent phosphorylation of AKT in both MA-2 and 451Lu-R cells in vitro.These findings suggest that ERBB3 may serve as a target for treating metastatic melanomas that are resistant to BIs.In support of this, administration of the pan-ERBB inhibitor, canertinib, significantly suppresses the metastasis formation of BI-resistant melanoma cell lines.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY, USA.

ABSTRACT
Melanoma is curable when it is at an early phase but is lethal once it becomes metastatic. The recent development of BRAF(V600E) inhibitors (BIs) showed great promise in treating metastatic melanoma, but resistance developed quickly in the treated patients, and these inhibitors are not effective on melanomas that express wild-type BRAF. Alternative therapeutic strategies for metastatic melanoma are urgently needed. Here we report that ERBB3, a member of the epidermal growth factor receptor family, is required for the formation of lung metastasis from both the BI-sensitive melanoma cell line, MA-2, and the BI-resistant melanoma cell line, 451Lu-R. Further analyses revealed that ERBB3 does not affect the initial seeding of melanoma cells in lung but is required for their further development into overt metastases, indicating that ERBB3 might be essential for the survival of melanoma cells after they reach the lung. Consistent with this, the ERBB3 ligand, NRG1, is highly expressed in mouse lungs and induces ERBB3-depdnent phosphorylation of AKT in both MA-2 and 451Lu-R cells in vitro. These findings suggest that ERBB3 may serve as a target for treating metastatic melanomas that are resistant to BIs. In support of this, administration of the pan-ERBB inhibitor, canertinib, significantly suppresses the metastasis formation of BI-resistant melanoma cell lines.

No MeSH data available.


Related in: MedlinePlus