We have elucidated the pharmacological action of the anti-
matrix metalloproteinase inhibitor BE16627B on
glioma cells. The study was limited to the noncytotoxic dose range. The aim of the study was to investigate whether the cytotoxicity of
BE16627B, an anti-
MMP agent, is related to apoptosis in the human
malignant glioma cell lines U87MG, U251MG, and U373MG. MTT assay was performed to detect the cytotoxic dose range.
Agarose gel electrophoresis was performed with purified genomic
DNA following exposure to 20 to 500 microM
BE16627B for 24 h, compared with 0 microM for the control group. Transmission electron microscopy (TEM) was employed to study nuclear fragmentation following exposure to 0, 20, and 500 microM of the agent for 24 h. An in situ endolabeling assay was performed to determine the index of apoptotic induction. MTT assay revealed that concentrations of 100 microM and above were cytotoxic.
DNA laddering was demonstrated in
agarose gel electrophoresis. TEM disclosed condensing and fragmentation of the
chromatin. None of these changes were observed in the control group and the noncytotoxic dose group. The in situ endolabeling study disclosed that the apoptotic index was significantly elevated by cytotoxic doses of this agent (U373MG; control, 4.0%; 500 microM, 68.5%). These results indicated that cytotoxic concentrations of
BE16627B induced apoptosis in human
malignant glioma cell lines. In our previous report, this agent inhibited activity of
MMP in noncytotoxic concentrations. Further study should be done to determine the pharmacological action of toxic
BE16627B.