SLPI and nasopharyngeal carcinoma: In their review [53], Bouchard et al. reported that secretory leukocyte peptidase inhibitor (SLPI) expression was highly up-regulated in pancreatic, papillary thyroid, uterine cervix, endometrial, and ovarian cancers; by contrast, SLPI was underexpressed in nasopharyngeal carcinoma, bladder tumors, and some breast carcinomas, although the overexpression of this protein correlates with more invasive forms of breast carcinoma [54,55,56].