To the Editor:

This letter serves as an acknowledgment that in the Introduction section of our article on the influence of casein kinase II on human rhabdomyosarcoma cells published in Clinical Cancer Research (1), the text of paragraph 2, lines 7 through 42 on page 6651 was directly copied from an article by David W. Litchfield in Biochemical Journal (2).

Further, segments of the Discussion section on page 6658 of our article were also copied from the article in Biochemical Journal, specifically, column 1, paragraph 1, lines 10 through 19, and column 2, lines 6 through 10.

We sincerely regret this error and wish to offer the assurance that it was an oversight and was unintentional. We offer our genuine and most sincere apology to Dr. Litchfield and the Biochemical Journal and to the readers of Clinical Cancer Research.

Izeradjene K, Douglas L, Delaney A, Houghton JA. Influence of casein kinase II in tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis in human rhabdomyosarcoma cells.
Clin Cancer Res
Litchfield DW. Protein kinase CK2: structure, regulation and role in cellular decisions and death.
Biochem J