Table I.

Regression of KS-like lesions in vivo by paclitaxela

Expt.TreatmentMice TreatedLesion Size at Sacrifice (mean cm2)bRegressing Area % (mean)c
1Paclitaxel 200 μg (five doses)20.642.5
Paclitaxel 500 μg (five doses)20.4462.5
Saline solution (five doses)20.510.0
2Paclitaxel 500 μg (two doses)31.166.0
Saline solution (two doses)10.90.0
  • a Four- to 6-wk-old CD1 nu/nu mice were inoculated s.c. with KSC (3 × 106) to induce formation of KS-like lesions as described previously (4 ). Twenty-four hours later, the animals were injected i.p. daily for 5 days with 200 μg or 500 μg of paclitaxel (Expt. 1), or they received only two doses (500 μg) on days 0 and 3 (Expt. 2). Control animals were injected with saline solution. On day 6 the mice were sacrificed, and KS-like lesions present at the injection site were excised in toto and processed for histologic examination by hematoxylin-eosin staining of lesion cross-sections.

  • b Lesion area (cm2) determined as described in Materials and Methods by caliper measurement of the two major perpendicular diameters.

  • c Percentage (%) of the regression area over the whole KS-like lesion area, characterized by necrotic tissue and cells with picnotic nuclei, inflammatory cell infiltration (macrophages and polymorphonucleated cells), and absence of vessels.