Posted: Monday, April 11, 2022
Julia H. Carter, PhD, of the Wood Hudson Cancer Research Laboratory, Newport, Kentucky, and colleagues conducted a study to determine whether cathepsin L may be an independent prognostic factor in urinary bladder cancer after controlling for disease stage and grade. The results of this retrospective analysis, which were presented during the American Association for Cancer Research (AACR) Annual Meeting 2022 (Abstract 5130), suggested the loss of this cysteine endopeptidase may be associated with increased intracellular levels of the growth factor receptors responsible for cell proliferation and disease progression
Tumor samples from 41 women and 92 men were classified according to subtype, depth of invasion, and grade. Immunohistochemical analyses were performed to assess the expression levels of cathepsin L and the prognostic marker Ki67.
A high level of cathepsin L expression was detected in normal urothelium (P < .0001). The levels of cathepsin L expression seemed to be similar between normal urothelium and stage 0 grade 1 (P = .9070), 2 (P = .2560), and 3 (P = .0722) urinary bladder cancers; however, in stage 0 grade 4 urinary bladder cancer, the level of cathepsin L expression appeared to be significantly reduced (P = .0011). The investigators reported a significant reduction in the level of cathepsin L expression in grade 3 and 4 papillary tumors versus grade 1 and 2 papillary tumors (P = .0002) and in grade 3 and 4 nonpapillary tumors versus grade 3 and 4 papillary tumors (P = .0133).
In each disease subtype, grade, and stage, cell proliferation detected by Ki67 expression seemed to significantly increase when the level of cathepsin L expression was reduced (P < .0001). Significantly reduced expression levels of cathepsin L were found to be associated with tumor recurrence (P = .03) and urinary bladder cancer–related death (P < .0001).
Disclosure: The study authors reported no conflicts of interest.