Although not enough data are available on the synergistic combination therapy of CIK cells with CTLA-4 in lung cancers, especially in the clinic, which may indicate an intriguing avenue about the need for further investigation, some studies suggest that the quality and quantity of CIK/DC-CIK cells against various tumor cell lines, in vivo and in vitro, are in some way intensified by inhibition of CTLA-4 (Table 2 and Figure 1). This evidence concerns the gene CTLA4 and lung cancer.