Nature Med. 5, 828– 831 (1999).

On page 829, the legend for Fig 1 was incorrect. The corrected figure and legend are shown here. We regret this error.

Fig. 1 Skin carcinogenesis in wild-type and TNF-α–/– mice. a, Initiation promotion. Mice were treated with one dose of 25 μg DMBA and then 4 μg TPA three times weekly for 15 weeks. C57Bl6/129 (▪), n = 14; TNF-α–/– (), n = 15. b, Initiation promotion. Mice were treated with one dose of 25 μg DMBA and then 4 μg TPA twice weekly for 15 weeks. Balb/c (▪), n = 14; TNF-α–/– (), n = 13. c, Complete carcinogenesis. Mice were treated with 5.1 μg DMBA twice weekly for 20 weeks. C57Bl6/129 (▪), n = 15; TNF-α–/– (), n = 20. d, Initiation promotion. Mice were treated with one dose of 25 μg DMBA and then 4 μg TPA twice weekly. C57Bl6/129 (▪), n = 15; MCP-1–/– (), n = 15.