Likewise, the HCC biomarker cystatin C, an inhibitor of cystein proteinases, showed significantly higher levels also in sera from lung cancer patients [132], and the HCC and lung cancer putative biomarker alpha-1 acid glycoprotein 1, an acute phase protein, was found as well elevated in sera and tumor tissues from patients affected by gastric carcinoma [133]. Here, CST3 is linked to lung cancer.