Can I use microarray data for signaling pathway analysis in cancer cell? For example, compare normal and tumor tissue microarray data to find deferentially expressed genes, and then put them into DAVID or GO to check which "signaling" pathway(s) they are involved in. I know that signaling pathway is based on post-transcriptional modification. But I believe that the gene of some members involved in certain signaling pathway should be turn on if the certain signaling pathway is on, hence I can get some useful information about signaling pathway from microarray data. I just wonder why almost no articles are talking about using microarray data for "signaling" pathway analysis. Is my concept incorrect ? Or actually there are some related papers that I've missed ?