Correction for “Strategy for reversing resistance to a single anticancer agent in human prostate and pancreatic carcinomas,” by Irina V. Lebedeva, Ilyas Washington, Devanand Sarkar, Jennifer A. Clark, Robert L. Fine, Paul Dent, David T. Curiel, Nicholas J. Turro, and Paul B. Fisher, which was first published February 27, 2007; 10.1073/pnas.0700042104 (Proc. Natl. Acad. Sci. U.S.A. 104, 3484–3489). The authors note that Fig. 4 appeared incorrectly. Specifically, the authors note the Western blot image presented in the first panel of Fig. 4 was an earlier blot, reflecting the correct experimental results but not of publication quality, used as a placeholder while drafting the manuscript. Publication quality blots were obtained but the original placeholder blot was not replaced. The corrected figure and its legend appear below. The online version has been corrected.