Cytotoxicity of camptothecin against human PCC/PGL cells in primary cultures.

Dissociated primary tumor cells from PCCs or PGLs representing different genotypes were cultured in the presence of 1 uM or 10 uM camptothecin compared to control medium. Counts were derived by counting all stained cells defined by a randomly placed square coverslip in a 35 mm culture dish (see Figure 1). All counts were done at 2 weeks except for tumor 7 (**), which was counted at 1 week because of extensive cell death caused by particular sensitivity to camptothecin. The two tumors listed as sporadic negative were tested negative for MEN2 RET mutation and for SDHB, SDHC and SDHD mutations and deletions.