Comprehensive Histopathological and Biochemical Analyzes of Prostatic Amyloid Bodies (Corpora Amylacea) From Autopsy Samples From Japanese Patients.

Background: Amyloid bodies (corpora amylacea) are found in the prostate and other organs, and their abnormal accumulation can lead to amyloidosis. However, it remains unclear how the constituents and pathological significance of amyloid bodies differ between tissues.

Methods: We performed pathological, proteomic, and biochemical analyzes of prostatic amyloid bodies isolated from 53 consecutive patients who underwent pathological autopsy at Kumamoto University from 2006 to 2017. Amyloid bodies were isolated using laser microdissection, and their constituents were analyzed by liquid chromatography-tandem mass spectrometry, immunohistochemistry, and immunoblotting.

Results: Prostatic amyloid bodies were found in samples from 47 of the 53 patients (89%). The most frequently detected proteins were lactoferrin (100%), S100-A9 (90.9%), prostate-specific antigen (90.9%), and cytoskeleton-associated protein 2-like (90.9%). Amyloid-associated proteins, such as apolipoprotein E (72.7%), vitronectin (54.5%), and serum amyloid P component (36.4%), were also present but were less prevalent. Prostatic amyloid bodies were more common in patients with benign prostatic hyperplasia (N = 25) than in other patients (N = 28).

Conclusions: These results suggest that amyloid bodies from different tissues may share some constituents. Our findings support further investigation to determine the relationship between the constituents of prostatic amyloid bodies and the pathophysiology of prostatic diseases.