FNDC4 and idiopathic pulmonary fibrosis: Of the thirty-five novel candidate hub genes from the brown module, 14 genes (CDH3, CFI, CHRDL2, COL10A1, CRABP2, DCLK1, DOK5, FNDC4, GPX8, SCRG1, SPRR1A, STEAP1, STEAP2, and TDO2) were found to be overexpressed in all the three IPF stages (Table 2).