In this study, as examples, we found that lncRNAs, HCCL5, HOTAIRM1, LINC00364 and PCBP2-OT1, which have been reported to promote the growth of cancer cells using pcDNA3/3.1, could not play the same role when expressed by lentiviral vector pCDH. This evidence concerns the gene HOTAIRM1 and cancer.