GREM1 and idiopathic pulmonary fibrosis: Interestingly, 3 out of the 4 markers (GREM1, MMP7, CTHRC1 and FHL2) identified by Kaminski and colleagues [43] as having a significant negative correlation with %DlCO and as markers that separate IPF patients by disease severity were expressed at a higher level in Subset 2 of GSE47460 (Kaminski-LGRC bulk expression cohort) [14–17] (S2 Fig), which suggested a differential prognosis for the two subsets of IPF patients.