CRM197 is a naturally nontoxic
diphtheria toxin mutant that binds and inhibits
heparin-binding
epidermal growth factor-like
growth factor.
CRM197 serves as
carrier protein for
vaccine and other therapeutic agents.
CRM197 also inhibits the growth, migration, invasion, and induces apoptosis in various
tumors.
Vascular cell adhesion molecule-1 (VCAM-1) is an important cell surface adhesion molecule associated with
malignancy of
gliomas. In this work, we aimed to investigate the role and mechanism of
CRM197 combined with
shRNA interference of
VCAM-1 (shRNA-VCAM-1) on the migration, invasion, and apoptosis of
glioblastoma cells. U87 and U251 human
glioblastoma cells were treated with
CRM197 (10 µg/ml) and
shRNA interfering technology was employed to silence
VCAM-1 expression. Cell viability, migration, invasiveness, and apoptosis were assessed with CCK8, Transwell and
Annexin V-PE/7-AAD staining. Activation of cleaved
caspase-3, 8, and 9, activity of
matrix metalloproteinase-2/9 (
MMP-2/9), and expression of phosphorylated Akt (p-Akt) were also checked. Results showed that
CRM197 and shRNA-VCAM-1 not only significantly inhibited the cell proliferation, migration, invasion, but also promoted the apoptosis of U87 and U251 cells. Combined treatment of both displayed enhanced inhibitory effects on the malignant
biological behavior of
glioma cells. The activation of cleaved
caspase-3, 8, 9 was promoted, activity of MMP-2 and MMP-9 and expression of p-Akt were inhibited significantly by the treatment of
CRM197 and shRNA-VCAM-1 alone or in combination, indicating that the combination of
CRM197 with shRNA-VCAM-1 additively inhibited the malignant behavior of human
glioblastoma cells via activating
caspase-3, 8, 9 as well as inhibiting MMP-2, MMP-9, and Akt pathway.