The original data of IHC scoring. The expression of CKS1 and p27KIP1 had been tested in 168 cases of paraffin-embedded tissue from the primary NPC patients and 49 cases of non-cancerous nasopharyngeal control specimen from independent patients by IHC. The percentage of positive cells was divided into five grades (percentage scores):<10% (0), 11–25% (1), 26–50% (2), 51–75%(3), and >75% (4). The intensity of staining was divided into four grades (intensity scores): no staining (0), light brown (1), brown (2),and dark brown (3). Staining positivity was determined by the formula: overall scores = percentage score × intensity score. The total score ranged from 0 to 12, with negative staining (0–1) and positive expression (2–12). At last, 0 presented negative staining and 1 presented positive staining in the data file. (XLS 42 kb