SPARC and idiopathic pulmonary fibrosis: However, this link was widely reported both at transcript and protein levels, both in cell lines and primary tumor tissues (Fabrizio et al., 2020; Liu et al., 2018; Li et al., 2022; Nagaraju and El-Rayes, 2013) and was also in vitro confirmed in our study, since SPARC expression was restored in the UIP lung cell line FF24 upon treatment with the demethylating agent 5-Aza-Cdr.