Expression of Cux-1, p21, and p27 protein in livers from wild type and transgenic mice. Fifty micrograms of nuclear extract prepared from 8-month-old transgenic and wild type livers was subjected to SDS–PAGE and transferred to nitrocellulose membranes. The presence of Cux-1, p21, p27, and β-actin (as a loading control) was detected by Western blot analysis as described in the ‘‘Materials and Methods.’’ Cux-1 protein was elevated in the transgenic livers compared to wild type. p21 expression was decreased in the transgenic livers, compared to wild type, while p27 expression was unchanged.