Sulforaphane Inhibits Invasion via Activating ERK1/2 Signaling in Human Glioblastoma U87MG and U373MG Cells

Abstract

BackgroundGlioblastoma has highly invasive potential, which might result in poor prognosis and therapeutic failure. Hence, the key we study is to find effective therapies to repress migration and invasion. Sulforaphane (SFN) was demonstrated to inhibit cell growth in a variety of tumors. Here, we will further investigate whether SFN inhibits migration and invasion and find the possible mechanisms in human glioblastoma U87MG and U373MG cells.MethodsFirst, the optimal time and dose of SFN for migration and invasion study were determined via cell viability and cell morphological assay. Further, scratch assay and transwell invasion assay were employed to investigate the effect of SFN on migration and invasion. Meanwhile, Western blots were used to detect the molecular linkage among invasion related proteins phosphorylated ERK1/2, matrix metalloproteinase-2 (MMP-2) and CD44v6. Furthermore, Gelatin zymography was performed to detect the inhibition of MMP-2 activation. In addition, ERK1/2 blocker PD98059 (25 µM) was integrated to find the link between activated ERK1/2 and invasion, MMP-2 and CD44v6.ResultsThe results showed that SFN (20 µM) remarkably reduced the formation of cell pseudopodia, indicating that SFN might inhibit cell motility. As expected, scratch assay and transwell invasion assay showed that SFN inhibited glioblastoma cell migration and invasion. Western blot and Gelatin zymography showed that SFN phosphorylated ERK1/2 in a sustained way, which contributed to the downregulated MMP-2 expression and activity, and the upregulated CD44v6 expression. These molecular interactions resulted in the inhibition of cell invasion.ConclusionsSFN inhibited migration and invasion processes. Furthermore, SFN inhibited invasion via activating ERK1/2 in a sustained way. The accumulated ERK1/2 activation downregulated MMP-2 expression and decreased its activity and upregulated CD44v6. SFN might be a potential therapeutic agent by activating ERK1/2 signaling against human glioblastoma.

Sulforaphane inhibits invasion by phosphorylating ERK1/2 to regulate E-cadherin and CD44v6 in human prostate cancer DU145 cells

“…SFN may suppress cancer progression via a few anti-proliferative mechanisms (12)(13)(14)(15). In a previous study, we found that SFN inhibited invasion in human glioblastoma cells through activation of the ERK1/2 signaling pathway (16). However, whether SFN inhibits invasion in human prostate cancer cells remains to be determined.…”

“…Previous results demonstrated that human chorionic gonadotropin β (hCGβ) promoted cell migration and invasion in human glioblastoma and prostate cancer cells by increasing the expression and activity of MMP-2, resulting from the sustained activation of ERK1/2 (26,27). It was also found that the sustained phosphorylation of ERK1/2 by SFN contributed to the suppression of migration and invasion in human glioblastoma cells (16). Thus, in the present study, we investigated whether SFN inhibited invasion in human prostate cancer cells via sustained activation of ERK1/2 and the downstream signaling.…”

“…Altered expression or dysfunction of CD44 variant 6 (CD44v6) is involved in the aggressive behavior of various types of cancer and correlates with poor prognosis in human malignancies such as breast, leukemia, gastric and colorectal cancer (34)(35)(36)(37). Additionally, SFN-induced ERK1/2 phosphorylation contributed to CD44v6 expression in human glioblastoma cells (16). Therefore, we hypothesized that SFN regulates CD44v6 via the activation of ERK1/2 in human prostate cancer cells.…”

“…MMP-2, which is involved in the degradation of type Iv collagen and gelatin, is expressed at elevated levels in ovarian, uterine, breast, prostate cancer and melanoma (40)(41)(42). Previous results showed that ERK1/2 phosphorylation decreased the expression and activity of MMP-2 in glioblastoma cells (16). Thus, SFN may regulate MMP-2 through the ERK1/2 signaling pathway and contribute to the suppression of invasion in human prostate cancer cells.…”

The role of phytochemicals in modulating intrinsic human cellular defence processes

“…737 In a cell culture model, SFN inhibited glioblastoma cell migration and invasion. 738 SFN (20 µM) reduced the formation of cell pseudopodia by phosphorylating ERK1/2 in a sustained way, contributing to the downregulated MMP-2 (matrix metalloproteinase) expression and activity associated with metastasis.…”