Matrix detachment and proteasomal inhibitors diminish Sulf-2 expression in breast cancer cell lines and mouse xenografts

• Published in: Clinical & experimental metastasis Vol. 30; no. 4; pp. 407 - 415
• Main Authors: Khurana, Ashwani, Jung-Beom, Deok, He, Xiaoping, Kim, Sung-Hoon, Busby, Robert C., Lorenzon, Laura, Villa, Massimo, Baldi, Alfonso, Molina, Julian, Goetz, Matthew P., Shridhar, Viji
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.04.2013; Springer Nature B.V
• Subjects: Animals; Apoptosis; Biomedical and Life Sciences; Biomedicine; Blotting, Western; Breast Neoplasms - drug therapy; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Cancer Research; Carcinoma, Ductal, Breast - drug therapy; Carcinoma, Ductal, Breast - metabolism; Carcinoma, Ductal, Breast - secondary; Carcinoma, Lobular - drug therapy; Carcinoma, Lobular - metabolism; Carcinoma, Lobular - secondary; Cell Proliferation; Extracellular Matrix - metabolism; Female; Hematology; Humans; Immunoenzyme Techniques; Mice; Neoplasm Grading; Oncology; Proteasome Inhibitors - pharmacology; Real-Time Polymerase Chain Reaction; Research Paper; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - genetics; RNA, Small Interfering - genetics; Sulfotransferases - antagonists & inhibitors; Sulfotransferases - genetics; Sulfotransferases - metabolism; Surgical Oncology; Tumor Cells, Cultured; Xenograft Model Antitumor Assays; Breast cancer; Sulfatase 2; Growth factor
• ISSN: 0262-0898; 1573-7276
• DOI: 10.1007/s10585-012-9546-5

Sulfatase 2 (Sulf-2) has been previously shown to be upregulated in breast cancer. Sulf-2 removes sulfate moieties on heparan sulfate proteoglycans which in turn modulate heparin binding growth factor signaling. Here we report that matrix detachment resulted in decreased Sulf-2 expression in breast cancer cells and increased cleavage of poly ADP-ribose polymerase. Silencing of Sulf-2 promotes matrix detachment induced cell death in MCF10DCIS cells. In an attempt to identify Sulf-2 specific inhibitor, we found that proteasomal inhibitors such as MG132, Lactacystin and Bortezomib treatment abolished Sulf-2 expression in multiple breast cancer cell lines. Additionally, we show that Bortezomib treatment of MCF10DCIS cell xenografts in mouse mammary fat pads significantly reduced tumor size, caused massive apoptosis and more importantly reduced Sulf-2 levels in vivo. Finally, our immunohistochemistry analysis of Sulf-2 expression in cohort of patient derived breast tumors indicates that Sulf-2 is significantly upregulated in autologous metastatic lesions compared to primary tumors ( p  < 0.037, Pearson correlation, Chi-Square analysis). In all, our data suggest that Sulf-2 might play an important role in breast cancer progression from ductal carcinoma in situ into an invasive ductal carcinoma potentially by resisting cell death.