In contrast to TN-C and TN-W, we recently demonstrated that (i) TN-X is down-regulated at both mRNA and protein levels in the six cancers with the highest incidence and mortality worldwide (i.e. lung, breast, colorectal, prostate, stomach and liver cancers) and (ii) a low level of TNXB transcripts is correlated with a worse overall survival in patients suffering from breast or lung cancers (27). This evidence concerns the gene TNC and lung carcinoma.