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Newly generated heparanase knock-out mice unravel co-regulation of heparanase and matrix metalloproteinases.

Zcharia E, Jia J, Zhang X, Baraz L, Lindahl U, Peretz T, Vlodavsky I, Li JP - PLoS ONE (2009)

Bottom Line: Heparanase, a mammalian endo-beta-D-glucuronidase, specifically degrades heparan sulfate proteoglycans ubiquitously associated with the cell surface and extracellular matrix.Co-regulation of heparanase and MMPs was also noted by a marked decrease in MMP (primarily MMP-2,-9 and 14) expression following transfection and over-expression of the heparanase gene in cultured human mammary carcinoma (MDA-MB-231) cells.It is conceivable that MMP-2 and MMP-14, which exert some of the effects elicited by heparanase (i.e., over branching of mammary glands, enhanced angiogenic response) can compensate for its absence, in spite of their different enzymatic substrate.

View Article: PubMed Central - PubMed

Affiliation: Department of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.

ABSTRACT

Background: Heparanase, a mammalian endo-beta-D-glucuronidase, specifically degrades heparan sulfate proteoglycans ubiquitously associated with the cell surface and extracellular matrix. This single gene encoded enzyme is over-expressed in most human cancers, promoting tumor metastasis and angiogenesis.

Principal findings: We report that targeted disruption of the murine heparanase gene eliminated heparanase enzymatic activity, resulting in accumulation of long heparan sulfate chains. Unexpectedly, the heparanase knockout (Hpse-KO) mice were fertile, exhibited a normal life span and did not show prominent pathological alterations. The lack of major abnormalities is attributed to a marked elevation in the expression of matrix metalloproteinases, for example, MMP2 and MMP14 in the Hpse-KO liver and kidney. Co-regulation of heparanase and MMPs was also noted by a marked decrease in MMP (primarily MMP-2,-9 and 14) expression following transfection and over-expression of the heparanase gene in cultured human mammary carcinoma (MDA-MB-231) cells. Immunostaining (kidney tissue) and chromatin immunoprecipitation (ChIP) analysis (Hpse-KO mouse embryonic fibroblasts) suggest that the newly discovered co-regulation of heparanase and MMPs is mediated by stabilization and transcriptional activity of beta-catenin.

Conclusions/significance: The lack of heparanase expression and activity was accompanied by alterations in the expression level of MMP family members, primarily MMP-2 and MMP-14. It is conceivable that MMP-2 and MMP-14, which exert some of the effects elicited by heparanase (i.e., over branching of mammary glands, enhanced angiogenic response) can compensate for its absence, in spite of their different enzymatic substrate. Generation of viable Hpse-KO mice lacking significant abnormalities may provide a promising indication for the use of heparanase as a target for drug development.

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Morphological appearance of mammary glands from wt vs. Hpse-KO mice.Whole-mount preparations of mammary glands from 3-month-old virgin mice were stained with hematoxylin. Hpse-KO derived mammary glands (right panel) showed abundant side branches and alveolar structures compared with glands from age-matched wt animals (left panel).
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pone-0005181-g003: Morphological appearance of mammary glands from wt vs. Hpse-KO mice.Whole-mount preparations of mammary glands from 3-month-old virgin mice were stained with hematoxylin. Hpse-KO derived mammary glands (right panel) showed abundant side branches and alveolar structures compared with glands from age-matched wt animals (left panel).

Mentions: We have previously reported that transgenic virgin mice over-expressing the human heparanase gene (hpa-tg mice) exhibited abnormal abundant branching of ducts in the mammary gland and precocious alveolar structures, typical of pregnant mice [36]. Notably, these differences decreased during late stages of pregnancy and during involution and did not affect the function of the mammary gland. To our surprise, a similar morphology was noted in the mammary glands of 3-month old virgin homozygous Hpse-KO mice (Fig. 3, right panels), as compared to poorly developed mammary glands seen in the wt virgin mice (Fig. 3, Left panels). However, unlike the hpa-tg vs. control mice [36], there was no significant difference between the wt and Hpse-KO mice in the width of the primary ducts.


Newly generated heparanase knock-out mice unravel co-regulation of heparanase and matrix metalloproteinases.

Zcharia E, Jia J, Zhang X, Baraz L, Lindahl U, Peretz T, Vlodavsky I, Li JP - PLoS ONE (2009)

Morphological appearance of mammary glands from wt vs. Hpse-KO mice.Whole-mount preparations of mammary glands from 3-month-old virgin mice were stained with hematoxylin. Hpse-KO derived mammary glands (right panel) showed abundant side branches and alveolar structures compared with glands from age-matched wt animals (left panel).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2664924&req=5

pone-0005181-g003: Morphological appearance of mammary glands from wt vs. Hpse-KO mice.Whole-mount preparations of mammary glands from 3-month-old virgin mice were stained with hematoxylin. Hpse-KO derived mammary glands (right panel) showed abundant side branches and alveolar structures compared with glands from age-matched wt animals (left panel).
Mentions: We have previously reported that transgenic virgin mice over-expressing the human heparanase gene (hpa-tg mice) exhibited abnormal abundant branching of ducts in the mammary gland and precocious alveolar structures, typical of pregnant mice [36]. Notably, these differences decreased during late stages of pregnancy and during involution and did not affect the function of the mammary gland. To our surprise, a similar morphology was noted in the mammary glands of 3-month old virgin homozygous Hpse-KO mice (Fig. 3, right panels), as compared to poorly developed mammary glands seen in the wt virgin mice (Fig. 3, Left panels). However, unlike the hpa-tg vs. control mice [36], there was no significant difference between the wt and Hpse-KO mice in the width of the primary ducts.

Bottom Line: Heparanase, a mammalian endo-beta-D-glucuronidase, specifically degrades heparan sulfate proteoglycans ubiquitously associated with the cell surface and extracellular matrix.Co-regulation of heparanase and MMPs was also noted by a marked decrease in MMP (primarily MMP-2,-9 and 14) expression following transfection and over-expression of the heparanase gene in cultured human mammary carcinoma (MDA-MB-231) cells.It is conceivable that MMP-2 and MMP-14, which exert some of the effects elicited by heparanase (i.e., over branching of mammary glands, enhanced angiogenic response) can compensate for its absence, in spite of their different enzymatic substrate.

View Article: PubMed Central - PubMed

Affiliation: Department of Oncology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.

ABSTRACT

Background: Heparanase, a mammalian endo-beta-D-glucuronidase, specifically degrades heparan sulfate proteoglycans ubiquitously associated with the cell surface and extracellular matrix. This single gene encoded enzyme is over-expressed in most human cancers, promoting tumor metastasis and angiogenesis.

Principal findings: We report that targeted disruption of the murine heparanase gene eliminated heparanase enzymatic activity, resulting in accumulation of long heparan sulfate chains. Unexpectedly, the heparanase knockout (Hpse-KO) mice were fertile, exhibited a normal life span and did not show prominent pathological alterations. The lack of major abnormalities is attributed to a marked elevation in the expression of matrix metalloproteinases, for example, MMP2 and MMP14 in the Hpse-KO liver and kidney. Co-regulation of heparanase and MMPs was also noted by a marked decrease in MMP (primarily MMP-2,-9 and 14) expression following transfection and over-expression of the heparanase gene in cultured human mammary carcinoma (MDA-MB-231) cells. Immunostaining (kidney tissue) and chromatin immunoprecipitation (ChIP) analysis (Hpse-KO mouse embryonic fibroblasts) suggest that the newly discovered co-regulation of heparanase and MMPs is mediated by stabilization and transcriptional activity of beta-catenin.

Conclusions/significance: The lack of heparanase expression and activity was accompanied by alterations in the expression level of MMP family members, primarily MMP-2 and MMP-14. It is conceivable that MMP-2 and MMP-14, which exert some of the effects elicited by heparanase (i.e., over branching of mammary glands, enhanced angiogenic response) can compensate for its absence, in spite of their different enzymatic substrate. Generation of viable Hpse-KO mice lacking significant abnormalities may provide a promising indication for the use of heparanase as a target for drug development.

Show MeSH
Related in: MedlinePlus