Effect of 7-hydroxystaurosporine on glioblastoma cell invasion and migration1

Abstract

Aim: To investigate the effect of 7‐hydroxystaurosporine (UCN‐01), a selective protein kinase C (PKC) inhibitor, on cell growth, migration, and invasion in invasive human glioblastoma U‐87MG cells. Methods: PKC activity was determined based on the PKC‐catalyzed transfer of the 32P‐phosphate group from [g‐32P]ATP into a PKC‐specific peptide substrate. Cell viability was measured by MTT assay. Cell invasion and migration were evaluated by a Boyden chamber assay and scratch wound assay, respectively. Protein expression was analyzed using Western blot assay. The formation of 3‐dimensional cellular aggregates was examined by a cell‐cell aggregation assay. Results: UCN‐01 treatment resulted in concentration‐and time‐dependent inhibition of U‐87MG cell growth at higher doses (>100 nmol/L), and reduced cell invasion and migration capability at less cytotoxic doses (<100 nmol/L). UCN‐01 significantly repressed PKC activity. Consistent with this result, UCN‐01 blocked cell invasion stimulated by phorbel 12‐myristate‐13‐acetate (PMA) and ethanol (EtOH), 2 PKC activators. Enforced expression of the tumor suppressor genes BRCA1 and PTEN increased the anti‐invasion potential of UCN‐01. Exposure to UCN‐01 caused a dose‐dependent increase in cell adhesion molecule E‐cadherin. The effect of UCN‐01 on the formation of cell‐cell aggregation was significantly reduced by the addition of an anti‐E‐cadherin antibody. Conclusion: UCN‐01 inhibits the invasion and migration of human glioma cells. Accordingly, UCN‐01 can have potential clinical applications for the treatment of human glioma metastasis.

The protein kinase C inhibitor, H7, inhibits tumor cell invasion and metastasis in mouse melanoma via suppression of ERK1/2

“…Thus, PKC has been newly targeted for the treatment of cancer. Recently, the PKC inhibitor, 7-hydroxystaurosporine, was shown to inhibit tumor cell invasion and migration [19], but the mechanism by which it inhibits cell invasion and metastasis are unknown. In the present study, we investigated the mechanism by which H7, a PKC inhibitor, inhibits tumor cell invasion and metastasis in the mouse melanoma cell line B16BL6.…”

Epidermal Growth Factor Receptor Variant III–Induced Glioma Invasion Is Mediated through Myristoylated Alanine-Rich Protein Kinase C Substrate Overexpression

“…Furthermore, it is well known that PKC plays a major role in glioma cell invasion (11)(12)(13). One of the most common substrates of PKC is myristoylated alanine-rich PKC substrate (MARCKS).…”

Radiotherapy in Conjunction with 7-Hydroxystaurosporine: A Multimodal Approach with Tumor pO2as a Potential Marker of Therapeutic Response

“…Accordingly, cell cycle checkpoint inhibitors are being investigated in the hope that they will enhance cell killing after DNA damage by preventing cell cycle arrest, thereby driving cells to mitotic catastrophe. An added advantage with inhibitors such as UCN-01 is that extremely low concentrations (10–100 n M ) could be used to enhance therapeutic outcome (14, 15, 21, 22, 25, 26). Surprisingly, in spite of its inhibitory effect on various malignant cells, there have not been attempts to investigate its potential application in a multimodal approach along with external-beam radiotherapy.…”

“…Among these, UCN-01 (7-hydroxystaurosporine) was discovered by Eastman et al to inhibit S and G 2 checkpoint arrest in various malignant cell lines (15–17). UCN-01 inhibits Chk1 and has been investigated extensively in combination with chemotherapy (15, 18–21). However, little is known about its possible in vivo efficacy in conjunction with radiotherapy.…”