Figure 5. Effect of pan IR700 based PIT on UMUC5 xenograft.

About 3 million cells (per animal) re-suspended in 100µl of Matrigel : PBS (1:1) were injected subcutaneously on the right thigh of female athymic nude mice. Tumors were measured two times a week using external calipers. Tumor volumes were calculated using a formula Tumor volume (mm³) = Tumor length (mm) × Tumor breadth (mm)² × 0.5. After 7 days of injection of UMUC5 cells, tumors of volumes 50 – 100 mm³ were seen in all the injected mice. The mice were randomized to groups of 10/treatment.

A. (i) H & E staining of UMUC5 xenograft showing morphology and (ii) Staining of hEGFR for UMUC5 xenografts shows very high expression of EGFR similar to UMUC5 cells in vitro.

B. Both groups of mice received 120µg of pan IR700/animal by i.v. injection. Control group (blue solid squares) did not receive any near IR radiation, whereas experimental mice (pink solid circles) received 100J/cm² and 50J/cm² NIR 24 hours and 48 hours post pan IR700 injection respectively. Tumor growth was attenuated in experimental mice (pan IR700 + NIR group).

C. At the end of the experiment the mice were euthanized and tumors were dissected out and weighted. Control group (blue solid squares) had significantly higher tumor weights (median – 0.5 g) than the experimental group (pink solid circles) (median weight – 0.2 g).