Limits...
Downregulation of developmentally regulated endothelial cell locus-1 inhibits the growth of colon cancer.

Zou X, Qiao H, Jiang X, Dong X, Jiang H, Sun X - J. Biomed. Sci. (2008)

Bottom Line: Gene transfection of Del1-shRNA downregulated expression of Del1 in LS-174T cells in vivo and in vitro, but did not alter the proliferative or survival properties of cells in vitro.Both Del1-shRNA and VEGF-shRNA gene therapies exhibited anti-tumor activities and they also showed a synergistic effect in suppressing growth of colon tumors by anti-angiogenesis and anti-proliferation.Although further investigation to clarify the mechanisms explaining the role of Del1 in tumor growth, and the interaction between VEGF and Del1, is required, the results indicate that downregulation of Del1 presents a potent therapeutic strategy to combat colon cancer.

View Article: PubMed Central - HTML - PubMed

Affiliation: The Hepatosplenic Surgery Center, Department of General Surgery, The First Clinical College of Harbin Medical University, Harbin 150001, PR China. zouxiaolongbs@163.com

ABSTRACT
Developmentally regulated endothelial cell locus-1 (Del1) is an embryonic angiogenic factor expressed in early embryonic endothelial cells, but recently has been found to be expressed in some forms of cancers including colon and breast cancers, and melanoma, and human cancer cell lines. Overexpression of Del1 accelerates tumor growth by enhancing vascular formation, implying Del1 may be a potential target for anti-angiogenic cancer therapy. The study aims to investigate whether downregulation of Del1 could inhibit the growth of tumors established in nude Balb/c mice by subcutaneous implantation of human LS-174T colon cancer cells. The shRNA expression vectors targeting human Del1, and vascular endothelial growth factor (VEGF) were constructed. Gene transfection of Del1-shRNA downregulated expression of Del1 in LS-174T cells in vivo and in vitro, but did not alter the proliferative or survival properties of cells in vitro. Gene transfection of VEGF-shRNA downregulated expression of both VEGF and Del1 in LS-174T cells in vivo and in vitro. Both Del1-shRNA and VEGF-shRNA gene therapies exhibited anti-tumor activities and they also showed a synergistic effect in suppressing growth of colon tumors by anti-angiogenesis and anti-proliferation. Although further investigation to clarify the mechanisms explaining the role of Del1 in tumor growth, and the interaction between VEGF and Del1, is required, the results indicate that downregulation of Del1 presents a potent therapeutic strategy to combat colon cancer.

Show MeSH

Related in: MedlinePlus

shRNA gene transfection downregulates gene expression in vivo. Established LS-174T tumors (~100 mm3 in volume) were injected with either control vector (A, C), Del1-shRNA (B) or VEGF-shRNA (D) expression plasmids. Illustrated are representative tumor sections prepared 4 days following gene transfer, stained brown with Abs against Del1 (A, B) or VEGF (C, D). Tumoral expression of Del1 (E) or VEGF (F) was detected by Western blot analysis. Blots of homogenates from tumors injected with control vector (lane 1) and shRNA plasmid (lane 2) were stained with Abs against Del1 (upper row) (E), or VEGF (upper row) (F), and an anti-β-actin Ab (lower row). The density of each band was measured and normalized to that of β-actin. *Indicates a significant difference at P < 0.05 in the band intensities of Del1 or VEGF between control vector transfected groups.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2666667&req=5

Figure 2: shRNA gene transfection downregulates gene expression in vivo. Established LS-174T tumors (~100 mm3 in volume) were injected with either control vector (A, C), Del1-shRNA (B) or VEGF-shRNA (D) expression plasmids. Illustrated are representative tumor sections prepared 4 days following gene transfer, stained brown with Abs against Del1 (A, B) or VEGF (C, D). Tumoral expression of Del1 (E) or VEGF (F) was detected by Western blot analysis. Blots of homogenates from tumors injected with control vector (lane 1) and shRNA plasmid (lane 2) were stained with Abs against Del1 (upper row) (E), or VEGF (upper row) (F), and an anti-β-actin Ab (lower row). The density of each band was measured and normalized to that of β-actin. *Indicates a significant difference at P < 0.05 in the band intensities of Del1 or VEGF between control vector transfected groups.

Mentions: A DNA/FuGENE™ 6 transfection vehicle containing shRNA expression vectors was injected into established LS-174T tumors (~100 mm3). Immunohistochemical staining of tumor sections prepared from tumors 4 days after transfection revealed that Del1 was intensely expressed in control vector-treated tumors (Figure 2A), whereas Del1-shRNA transfection resulted in markedly downregulation of Del1 in situ (Figure 2B). The results were confirmed by Western blot analysis (Figure 2E). Similarly, gene transfection of VEGF-shRNA greatly downregulated expression of VEGF in situ (Figure 2C vs. Figure 2D) as revealed by immunohistochemical analysis and confirmed by Western blot analysis (Figure 2F).


Downregulation of developmentally regulated endothelial cell locus-1 inhibits the growth of colon cancer.

Zou X, Qiao H, Jiang X, Dong X, Jiang H, Sun X - J. Biomed. Sci. (2008)

shRNA gene transfection downregulates gene expression in vivo. Established LS-174T tumors (~100 mm3 in volume) were injected with either control vector (A, C), Del1-shRNA (B) or VEGF-shRNA (D) expression plasmids. Illustrated are representative tumor sections prepared 4 days following gene transfer, stained brown with Abs against Del1 (A, B) or VEGF (C, D). Tumoral expression of Del1 (E) or VEGF (F) was detected by Western blot analysis. Blots of homogenates from tumors injected with control vector (lane 1) and shRNA plasmid (lane 2) were stained with Abs against Del1 (upper row) (E), or VEGF (upper row) (F), and an anti-β-actin Ab (lower row). The density of each band was measured and normalized to that of β-actin. *Indicates a significant difference at P < 0.05 in the band intensities of Del1 or VEGF between control vector transfected groups.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2666667&req=5

Figure 2: shRNA gene transfection downregulates gene expression in vivo. Established LS-174T tumors (~100 mm3 in volume) were injected with either control vector (A, C), Del1-shRNA (B) or VEGF-shRNA (D) expression plasmids. Illustrated are representative tumor sections prepared 4 days following gene transfer, stained brown with Abs against Del1 (A, B) or VEGF (C, D). Tumoral expression of Del1 (E) or VEGF (F) was detected by Western blot analysis. Blots of homogenates from tumors injected with control vector (lane 1) and shRNA plasmid (lane 2) were stained with Abs against Del1 (upper row) (E), or VEGF (upper row) (F), and an anti-β-actin Ab (lower row). The density of each band was measured and normalized to that of β-actin. *Indicates a significant difference at P < 0.05 in the band intensities of Del1 or VEGF between control vector transfected groups.
Mentions: A DNA/FuGENE™ 6 transfection vehicle containing shRNA expression vectors was injected into established LS-174T tumors (~100 mm3). Immunohistochemical staining of tumor sections prepared from tumors 4 days after transfection revealed that Del1 was intensely expressed in control vector-treated tumors (Figure 2A), whereas Del1-shRNA transfection resulted in markedly downregulation of Del1 in situ (Figure 2B). The results were confirmed by Western blot analysis (Figure 2E). Similarly, gene transfection of VEGF-shRNA greatly downregulated expression of VEGF in situ (Figure 2C vs. Figure 2D) as revealed by immunohistochemical analysis and confirmed by Western blot analysis (Figure 2F).

Bottom Line: Gene transfection of Del1-shRNA downregulated expression of Del1 in LS-174T cells in vivo and in vitro, but did not alter the proliferative or survival properties of cells in vitro.Both Del1-shRNA and VEGF-shRNA gene therapies exhibited anti-tumor activities and they also showed a synergistic effect in suppressing growth of colon tumors by anti-angiogenesis and anti-proliferation.Although further investigation to clarify the mechanisms explaining the role of Del1 in tumor growth, and the interaction between VEGF and Del1, is required, the results indicate that downregulation of Del1 presents a potent therapeutic strategy to combat colon cancer.

View Article: PubMed Central - HTML - PubMed

Affiliation: The Hepatosplenic Surgery Center, Department of General Surgery, The First Clinical College of Harbin Medical University, Harbin 150001, PR China. zouxiaolongbs@163.com

ABSTRACT
Developmentally regulated endothelial cell locus-1 (Del1) is an embryonic angiogenic factor expressed in early embryonic endothelial cells, but recently has been found to be expressed in some forms of cancers including colon and breast cancers, and melanoma, and human cancer cell lines. Overexpression of Del1 accelerates tumor growth by enhancing vascular formation, implying Del1 may be a potential target for anti-angiogenic cancer therapy. The study aims to investigate whether downregulation of Del1 could inhibit the growth of tumors established in nude Balb/c mice by subcutaneous implantation of human LS-174T colon cancer cells. The shRNA expression vectors targeting human Del1, and vascular endothelial growth factor (VEGF) were constructed. Gene transfection of Del1-shRNA downregulated expression of Del1 in LS-174T cells in vivo and in vitro, but did not alter the proliferative or survival properties of cells in vitro. Gene transfection of VEGF-shRNA downregulated expression of both VEGF and Del1 in LS-174T cells in vivo and in vitro. Both Del1-shRNA and VEGF-shRNA gene therapies exhibited anti-tumor activities and they also showed a synergistic effect in suppressing growth of colon tumors by anti-angiogenesis and anti-proliferation. Although further investigation to clarify the mechanisms explaining the role of Del1 in tumor growth, and the interaction between VEGF and Del1, is required, the results indicate that downregulation of Del1 presents a potent therapeutic strategy to combat colon cancer.

Show MeSH
Related in: MedlinePlus