Sulfatase 2 promotes breast cancer progression through regulating some tumor-related factors

Abstract

In previous studies Sulf2 has been evidenced to play an important role in tumor progression through editing sulfate moieties on heparan sulfate proteoglycans (HSPGs) and modulating heparin binding growth factors. However, the role of Sulf2 in breast cancer progression is still poorly understood. In the present study, we hypothesized that Sulf2 promoted breast cancer progression. Two different breast cancer cell lines, MCF-7 and MDA-MB-231, were chosen for this study because of high and low Sulf2 expression levels. We also altered their Sulf2 expression by establishing Sulf2 knockdown and overexpressing breast cancer cell lines MCF-7 shSulf2 and MDA-MB-231 Sulf2. To evaluate the functions of Sulf2, cell proliferation, apoptosis, cell cycle, invasion, mobility and adhesion of these cell lines were measured in vitro, and xenograft formation, invasion and metastasis ability were examined in vivo. Furthermore, expression of related genes were screened and were certified in these cell lines. We found that Sulf2 increased breast cancer proliferation, invasion, mobility and adhesion both in vitro and in vivo. Sulf2 also decreased cisplatin inducing breast cancer apoptosis without affecting the cell cycle. Sulf2 upregulated c-fos induced growth factor (FIGF) and nuclear receptor subfamily 4 group A member 3 (NR4A3) expression and downregulated the cluster of differentiation 82 (CD82) and platelet-derived growth factor C (PDGFC) expression in breast cancer. Our data confirmed that Sulf2 promoted breast cancer progression and regulated the expression of tumor-related genes in breast cancer.

Sulfatase 2 facilitates lymphangiogenesis in breast cancer by regulating VEGF-D

“…MCF-7 cells release high levels of Sulf2 protein in the supernatant which was confirmed in our previous study (6). The MCF-7 cells were cultured in DMEM until 80% confluence and were subsequently cultured in OptiMEM (HyClone Laboratories, Inc.) for another 72 h. The supernatant was collected and concentrated using Amicon Ultra filters 30 D (Millipore, Billerica, MA, USA) and then was kept in 50 mM HEPES buffer (pH 8.0; Biochrom GmbH, Berlin, Germany) for further study.…”

“…Equal amounts of proteins from the cells were resolved on SDS-PAGE and then transferred onto PVDF membranes as previously described (6). The membranes were separately probed with rabbit anti-FIGF (1:1,000, PAB4879; Abnova, Atlanta, GA, USA), rabbit anti-AKT1 (1:1,000, ab32505), rabbit anti-pAKT1 (s473) (1:1,000, ab66138; both from Abcam, Cambridge MA, USA), rabbit anti-mouse LYVE-1 (1:1,000, ab36993; AngioΒio, San Diego, CA, USA), rabbit anti-GAPDH (1:500; Sigma-Aldrich) for 1 h. Subsequently, the membranes were washed with TBST, and then incubated with goat anti-rabbit HRP (1:500; Sigma-Aldrich) for 1 h. Bound antibody chemiluminescence was detected using chemiluminescence kits (Thermo Fisher Scientific, Darmstadt, Germany).…”

“…Previously, we demonstrated that VEGF-D/FIGF, a member of the VEGF family, was upregulated by Sulf2 (6). In this study, we hypothesized that Sulf2 facilitates lymphangiogenesis in breast cancer by regulating VEGF-D. To evaluate the functions of Sulf2 in lymphangiogenesis in breast cancer, we examined the proliferation, apoptosis, cell cycle, mobility and tube-like structure formation of LECs in vitro , as well as lymphangiogenesis in mouse ears and xenografts in vivo .…”

“…The Sulf family includes two structurally similar endogenous sulfatases (Sulf1 and Sulf2) with 64% homology in highly conserved heparin-binding domains, but with different functions (2–4). Sulfatase 2 (Sulf2) is an extracellular endoglucosamine-6-sulfatase and considered as a bona fide cancer-causing agent in multiple types of cancer (6,7). Sulf2 is overexpressed in many tumor cells and was shown to promote tumorigenesis in many human cancers such as hepatocellular (8), pancreatic (9), ovarian (10), breast (6,10), and non-small cell lung carcinoma (11).…”

“…Sulfatase 2 (Sulf2) is an extracellular endoglucosamine-6-sulfatase and considered as a bona fide cancer-causing agent in multiple types of cancer (6,7). Sulf2 is overexpressed in many tumor cells and was shown to promote tumorigenesis in many human cancers such as hepatocellular (8), pancreatic (9), ovarian (10), breast (6,10), and non-small cell lung carcinoma (11). Sulf2 also increased the activities of growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor-1 (FGF-1), and certain chemokines such as stromal cell-derived factor-1 (SDF-1) and secondary lymphoid-tissue chemokine (SLC), stimulating the biological functions of endothelial cells to promote angiogenesis (5,12).…”