HIPK2 and idiopathic pulmonary fibrosis: In agreement with these findings, a previous study showed reduction in HIPK2 expression, due to a loss of heterozygosity (LOH) at HIPK2 locus 7q32.34, in human lung fibroblasts derived from IPF patients [97], although the molecular mechanisms underlying HIPK2 reduction and its correlation with IPF was not determined.