SPARC and lung cancer: Among the several reported dysregulation mechanisms of SPARC expression, the aberrant methylation at the promoter region of SPARC gene has been widely reported in many solid tumors, such as endometrial, colon, pancreatic, ovarian cancer and lung cancer, and could lead to a worse clinical outcome in this group of patients (Fabrizio et al., 2020; Liu et al., 2018; Nagaraju and El-Rayes, 2013; Zhang et al., 2012).