Pairwise analysis

The directions of expression change of the remaining non-tissue-specific DE-lncRNAs were checked in six patients with both primary and metastatic tumors by calculating the mean expression values of DE-lncRNAs in metastatic tumors for each patient and comparing them against the expression value of their corresponding primary tumor from the same patient. For the patient with two primary tumors, the means of expression values of DE-lncRNAs in both primary and metastatic tumors were calculated separately and compared against each other. lncRNAs that displayed expression changes in opposite directions in more than two patients were removed from the list of DE-lncRNAs of interest.