Prognostic value of phosphorylated CREB (p-CREB) for lung cancer. A and B. Immunochemistry staining of p-CREB on a lung cancer tissue microarray (A: 10× magnification; B: 400× magnification). Positive stains (brown) of p-CREB were seen in tumor cell nuclei. C and D. Survival analysis using p-CREB (C) and total CREB (D) expression. The results showed that p-CREB expression correlated better survival. In contrary, expression of unphosphorylated CREB had not prognostic value.