TGFβ is associated with decreased half-life of RXFP1 in human lung fibroblasts. GAP scores were calculated on the IPF patients in the LTRC dataset, and the patients were assigned a GAP stage from 1 to 3. Gene expression by microarray for RXFP1 (A), RXFP2 (B), and RXFP3 (C) were plotted as a function of increasing GAP stage. For GAP 1, n = 45; GAP 2, n = 75; and GAP 3, n = 14. Data were analyzed by Kruskal-Wallis, and p values are indicated in the panel. D, donor (n = 3), and E, IPF (n = 3) lung fibroblasts were processed for quantitative RT-PCR for RXFP1 at several time points following incubation with TGFβ and actinomycin D. Data represent the percentage of relative abundance of RXFP1 mRNA remaining compared with the 0-h time point, and the best fit curves for RXFP1 decay were plotted. F, dark line indicates data representing relative abundance of RXFP1 expression of RXFP1 mRNA remaining compared with the 0-h time point for donor fibroblasts. Dotted line indicates the percentage of relative abundance of RXFP1 expression in IPF fibroblasts at the indicated time points normalized to the levels of RXFP1 mRNA of donor fibroblasts at the 0-h time point. Data represent the relative abundance of miR-144-3p (ΔΔCt) remaining compared with the 0-h time point, and the best fit curves for miR-144-3p decay were plotted.