Copper zinc superoxide dismutase, nuclear DNA content, and progression in human gliomas

To our knowledge, there have been no previous reports regarding the immunoh istochemistry and image cytometry to demonstrate elevated Copper/zinc super oxide dismutase (Cu/Zn SOD) expression and numbers of the clonal cells in h uman gliomas. In 30 well-studied patients with gliomas, immunoreactivity fo r Cu/Zn SOD and cytometric evidence of DNA ploidy in the G2M cell cycle pha se were evaluated from routinely prepared tissue blocks. Cu/Zn SOD positive tumor cells were shown in 8 of 13 glioblastomas (mean qu antitative immunoreactivity SOD score; 1), 3 of 8 anaplastic gliomas (score ; 0.6), and none of 9 low-grade gliomas. The differences in SOD score was n ot significant. In hypertetraploid glioblastomas, time to progression was s horter than for hypertetraploid of anaplastic gliomas, while SOD scores wer e not significantly different. The same relationship held for tetraploid sp ecimens. Considering variables in combination, hypertetraploid gliomas with high SOD immunoreactivity showed a significantly short time to progression (p < 0.05) (1-5 months after radiotherapy and chemotherapy) compared with hypertetraploid, low-SOD immunoreactivity gliomas or tetraploid, low-SOD im munoreactivity gliomas. The tumor cells with high SOD activity also tended to be resistant for radi otherapy and anticancer drugs. Those results were suggested that the high g rade glioma with a single clone and low SOD activity were effective for rad iotherapy associated with oxidative stress, and that the high grade gliomas with more than two clones and high SOD activity were very less effective f or same therapy. Cu/Zn SOD activity and the degree of the clonality in human gliomas should be very important factors influencing a choice of oxidative cytotoxic treat ment.