However, tumor tissues are thought to be hetero-geneous in IL-6 expression as the previous results on NSCLC cell lines indicated IL-6 expression in only 53% of NSCLC cell lines among the NSCLC cell lines tested [15, 16] and the report on patient tumor tissues also showed heterogeneous expression of IL-6 in lung tumor tissues [14]. This evidence concerns the gene IL6 and non-small cell lung carcinoma.