Considering that GPC1 was expressed in about 70% of PDAC cases (Table 1) and because several previous reports have described the oncogenic roles of glypicans in cancer, for example, GPC3 associated with the progression of malignant tumors of several types, including mesotheliomas and ovarian cancer, or a role for GPC1 in pancreatic cancer progression, we analyzed the role of GPC1 in pancreatic cancers using in vitro assays. This evidence concerns the gene GPC1 and mesothelioma.