Reverse transcriptase polymerase chain reaction, western blotting, and immunohistochemical analysis were used to examine the expression of RANKL, RANK, and OPG in human NSCLC cell lines with different metastatic potentials, as well as in 52 primary NSCLC samples and 75 NSCLC bone metastasis samples. This evidence concerns the gene TNFRSF11A and non-small cell lung carcinoma.