Interestingly, previous studies have shown that upregulation of HSPB5 expression in idiopathic pulmonary fibrosis (IPF) can reduce the expression of TRIM33 and weaken the interaction between TRIM33 and Smad4, thus hindering the ubiquitination and nuclear output of Smad4 [12]. Here, TRIM33 is linked to idiopathic pulmonary fibrosis.