Figure 4
From: Radiosensitization by a novel Bcl-2 and Bcl-XL inhibitor S44563 in small-cell lung cancer
S44563 enhanced the efficacy of radiotherapy in SCLC xenograft tumors and prolonged overall survival. (a) H146 (left part) and H69 xenograft tumor (right part). Kaplan–Meier survival curves after treatment with fractionated X-ray irradiation and S44563, alone or in combination. When tumors reached the appropriate size, the mice were randomized into 5–10 mice per group and treated with either S44563 100 mg/kg i.p., × 5 days or X-ray irradiation 2 Gy × 4, × 1 week, or their combination. The pictures are representative of two experiments. For each experiment, 6–10 mice were used for each group. Kaplan–Meier survival curves reflect significantly enhanced antitumor efficacy using IR+ S44563 regimen. The endpoint was relative tumor volume triple the initial tumor volume (RTV3). Log-rank test analysis demonstrated that the combination resulted in improved survival compared with S44563 or radiation alone (P=0.1 in H146 xenografts; P<0.05 in H69 xenografts). (b) Tumor growth volumes curves. Volume growth was analyzed on day 50 for H146 (P=0.1) and on day 37 for H69 xenografts (P=0.1). Standard deviations are shown. (c) H146-bearing mice were treated with S44563 (100 mg/kg, d1–d5), IR (four fractions, 2 Gy per fraction) or both and then were killed 2 h after the last treatment. Tumors were excised and stained for cleaved caspase-3
