Figure 1.

Simultaneous deletion of CtsB and CtsS reduces angiogenic switching and tumor growth but does not affect tumor invasion. (A) Angiogenic switching was assessed in 10.5-wk-old wild-type RT2 or CtsB^−/−S^−/− RT2 mice (n = 10 mice for both genotypes) by manually counting the number of angiogenic islets in the pancreas. The graph shows the average number of angiogenic islets per mouse. (B) Cumulative tumor volume, represented as the sum of the volumes of all tumors per mouse, was calculated for 13.5-wk-old wild-type RT2 (n = 57) and CtsB^−/−S^−/− RT2 (n = 46) mice. (C) Graph depicting the average number of tumors per mouse in wild-type and CtsB^−/−S^−/− RT2 animals at the 13.5-wk endpoint. The following numbers of animals were analyzed per group: wild-type RT2, n = 52; CtsB^−/−S^−/− RT2, n = 37. (D) Quantitation of Ki67⁺ cells in wild-type and CtsB^−/−S^−/− RT2 tumors relative to the total number of DAPI⁺ cells showed an 85% decrease in cell proliferation in tumors deficient for both CtsB and CtsS. All tumors from five wild-type RT2 and 11 CtsB^−/−S^−/− RT2 mice were analyzed. (E) Graph showing the proportions of encapsulated, microinvasive (IC1), and invasive (IC2) carcinomas in wild-type RT2 and CtsB^−/−S^−/− RT2 mice at 13.5 wk. The following numbers of samples were analyzed: wild-type RT2, 18 mice, 97 tumors; CtsB^−/−S^−/− RT2, 14 mice, 68 tumors. The graphs show mean + SEM. Statistical significance was calculated by unpaired two-tailed Student's t-test (A–D) or using a cumulative logit model with generalized estimating equations to correct for correlations within individual mice (E). (n.s.) Nonsignificant; (***) P < 0.001.