AUTHOR=Weidemann Sören , Lukas Böhle Jan , Luebke Andreas M., Kluth Martina , Büscheck Franziska , Hube-Magg Claudia , Höflmayer Doris , Möller Katharina , Fraune Christoph , Bernreuther Christian , Rink Michael , Simon Ronald , Menz Anne , Hinsch Andrea , Lebok Patrick , Clauditz Till S , Sauter Guido , Uhlig Ria , Wilczak Waldemar , Steurer Stefan , Burandt Eike , Krech Rainer , Dum David , Krech Till , Marx Andreas , Minner Sarah
TITLE=Napsin A Expression in Human Tumors and Normal Tissues
JOURNAL=Pathology and Oncology Research
VOLUME=27
YEAR=2021
URL=https://www.por-journal.com/journals/pathology-and-oncology-research/articles/10.3389/pore.2021.613099
DOI=10.3389/pore.2021.613099
ISSN=1532-2807
ABSTRACT=Background: Novel aspartic proteinase of the pepsin family A (Napsin A, TAO1/TAO2) is a functional aspartic proteinase which is involved in the maturation of prosurfactant protein B in type II pneumocytes and the lysosomal protein catabolism in renal cells. Napsin A is highly expressed in adenocarcinomas of the lung and is thus commonly used to affirm this diagnosis. However, studies have shown that other tumors can also express Napsin A.
Methods: To comprehensively determine Napsin A expression in normal and tumor tissue, 11,957 samples from 115 different tumor types and subtypes as well as 500 samples of 76 different normal tissue types were evaluable by immunohistochemistry on tissue microarrays.
Results: Napsin A expression was present in 16 different tumor types. Adenocarcinoma of the lung (85.6%), clear cell adenocarcinoma of the ovary (71.7%), clear cell adenocarcinoma of the endometrium (42.8%), papillary renal cell carcinoma (40.2%), clear cell (tubulo) papillary renal cell carcinoma (16.7%), endometrial serous carcinoma (9.3%), papillary thyroid carcinoma (9.3%) and clear cell renal cell carcinoma (8.2%) were among the tumors with the highest prevalence of Napsin A positivity. In papillary and clear cell renal cell carcinoma, reduced Napsin A expression was linked to adverse clinic-pathological features (p ≤ 0.03).
Conclusion: This methodical approach enabled us to identify a ranking order of tumors according to their relative prevalence of Napsin A expression. The data also show that loss of Napsin A is linked to tumor dedifferentiation in renal cell carcinomas.