Annexin A2 Expression in the Aerogenous Spread of Pulmonary Invasive Mucinous Adenocarcinoma with Gastric Lineage

Spread through air spaces (STAS) is a unique form of lung cancer progression associated with a worse prognosis. However, the mechanisms underlying STAS and the associated proteins remain unclear. Annexin A2 (ANX A2), which is a membrane-binding protein involved in cell adhesion, is known to promote...

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Bibliographic Details
Main Authors: Kazumori Arai, Tomohiro Iwasaki, Chinatsu Tsuchiya, Akihiro Sonoda
Format: Article
Language:English
Published: Hindawi Limited 2020-01-01
Series:Case Reports in Oncological Medicine
Online Access:http://dx.doi.org/10.1155/2020/2492636
Description
Summary:Spread through air spaces (STAS) is a unique form of lung cancer progression associated with a worse prognosis. However, the mechanisms underlying STAS and the associated proteins remain unclear. Annexin A2 (ANX A2), which is a membrane-binding protein involved in cell adhesion, is known to promote cancer invasion. In this report, we describe the immunohistochemical analysis of ANX A2 expression in an invasive mucinous adenocarcinoma (IMAC) resected from a 63-year-old man in whom the tumor cells had detached from the alveolar wall and exhibited STAS. At the detachment site, we observed cytoplasmic ANX A2 positivity on the basal side and in the exfoliative gap, as well as reduced collagen IV positivity expression. This biomarker pattern suggested an IMAC with gastric lineage. We hypothesize that ANX A2 is secreted from the basal sides of tumor cells and induces tumor cell detachment by degrading the basement membrane. A further comparison of this case with an IMAC with nongastric lineage suggested the following probabilities: (1) ANX A2 likely contributes to STAS in a manner that is dependent on its subcellular localization. (2) Both the subcellular localization of ANX A2 and the detachment site depend on tumor cell characteristics, including the biomarker immunophenotype.
ISSN:2090-6706
2090-6714