Sox2 expression correlates with metastatic progression of adenocarcinoma. (A) Sox2 expression in Lung squamous cells carcinoma, adenocarcinoma and metastatic adenocarcinoma was analyzed from stage I/II or stage IV patients samples by immunohistochemistry. (B) Semi-quantitative scoring was performed for adenocarcinoma samples and the tumors with score of one or more was considered positive for Sox2 expression and listed. (C) Median score for Sox2 expression was calculated and plotted for different stages of NSCLC progression. The mean (± SD) of score is mentioned in parenthesis. Metastatic tumors showed significantly (p = 0.01) higher expression of Sox2.