Activation of the human HOTAIR promoter by Col-1. A) A549 cells were transfected with either pGL3 Basic luciferase reporter (Basic-Luc) or the human HOTAIR promoter-controlled luciferase reporter in the pGL3 Basic backbone (HOTAIR-Luc). The mRNA levels of the firefly luciferase reporter were measured using qRT-PCR and normalized to the co-transfected renilla luciferase reporter. A fold change in the expression of the firefly luciferase reporter was obtained by setting the values of Basic-Luc to one. B) The mRNA levels of the HOTAIR promoter-controlled luciferase reporter were measured in rBM ± Col-1 3-D cultures of A549 cells using qRT-PCR. A fold change in the mRNA levels of the luciferase reporter was obtained by setting the values from the rBM 3-D culture to one. Mean and standard deviations were obtained from three independent experiments. ** indicated a P value < 0.01 as determined using unpaired two tail student T test.