Fig 7.

Examination of subcutaneous tumourigenesis and solid tumour development in nude mice. Treatment (72 hrs) of U251MG cells: control (untreated control), transfection with a plasmid vector expressing scrambled siRNA (treated control), 100 nM taxol, transfection with a plasmid vector expressing Bcl-2 siRNA and taxol + Bcl-2 siRNA. (A) Inhibition of subcutaneous tumourigenesis in nude mice. The U251MG cells (carrying the luciferase gene) were treated as mentioned above and the, injected under the dorsal of skin of nude mice. Beginning from day 3, the mice received intraperitoneal injection of nothing (control) or scrambled siRNA vector or taxol or Bcl-2 siRNA vector or taxol + Bcl-2 siRNA vector on alternate days for 20 days. On day 21, the mice were injected with luciferin and visualized for luciferase activity. The data are representative of six mice in each treatment group. (B) Inhibition of solid tumour development in the subcutaneous tissue of nude mice. The U251MG cells (not carrying the luciferase gene) were treated as mentioned above, harvested and suspended in an equal volume of the Matrigel, and 100 μl of this suspension (5 × 10⁶ cells) was injected subcutaneously in nude mice. The animals were left for 2 weeks without any treatment. Afterwards, the mice received intraperitoneal injection of nothing (control) or scrambled siRNA vector or taxol or Bcl-2 siRNA vector or taxol + Bcl-2 siRNA vector on alternate days for 4 weeks. At the end of the sixth week, the tumours were surgically removed, weighed and photographed. (C) Longitudinal measurement of tumour volume in nude mice using a digital vernier caliper. The data are presented as mean ± S.D. of six animals in each treatment group. (D) Measurement of tumour weight following the treatments. The data are presented as mean ± S.D. of six animals in each treatment group (*P < 0.001 when compared with the scrambled siRNA treatment mean values and #P < 0.001 when compared with taxol or Bcl-2 siRNA treatment mean values).