Co-expression of parathyroid hormone and chromogranin A in secondary hyperparathyroidism: a functional marker for secretory activity of hyperplastic nodules.
The relationship between secretion of parathyroid hormone (PTH) and biologic characteristics, including cell proliferation or monoclonality, is not yet fully understood. To evaluate secretory activity of glands or nodules histopathologically, we focused on the co-expression of chromogranin A (CgA) and parathyroid hormone (PTH) in each gland or nodule. A total of 55 glands from 38 patients with normal parathyroid glands, hyperplastic glands (diffuse and nodular) and primary adenomas were compared. Co-expression of PTH and CgA was decreased to 44.4% in diffuse hyperplastic glands, and to 39.6% in 91 hyperplastic nodules, in contrast to normal glands and primary adenomas that showed constant co-expression of PTH and CgA. Immunohistochemical study of PTH showed a coarse granular pattern predominantly in PTH-positive/CgA-positive nodules, and a dot-like pattern mainly in PTH-positive/CgA-negative nodules. Laser scanning microscopy and immunoelectron microscopy confirmed that a dot-like pattern is based on a positive reaction of PTH at the Golgi apparatus. MIB-1 LI was 12.6 +/- 11.6 in PTH-positive/CgA-positive, and 19.3 +/- 27.3 in PTH-positive/CgA-negative nodules. In conclusion, a combination of PTH and CgA could provide more information about the physiologic state of secretory activity of each nodule than does the simple observation of PTH immunoreactivity.
Tanaka
Reika
R
Division of Nephrology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, Bohseidai, Isehara, Kanagawa, Japan.
Umemura
Shinobu
S
Kakuta
Takatoshi
T
Fujisaki
Tomotaka
T
Sakai
Hideto
H
Saitoh
Akira
A
Osamura
R Yoshiyuki
RY
D000236:Adenoma / Q000378:metabolism / Q000473:pathology; D053379:Chromogranin A; D002864:Chromogranins / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000378:metabolism* / Q000473:pathology; D006965:Hyperplasia / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000096:biosynthesis; D008297:Male; D018613:Microscopy, Confocal; D016253:Microscopy, Immunoelectron; D008875:Middle Aged; D010280:Parathyroid Glands / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure*; D010281:Parathyroid Hormone / Q000096:biosynthesis*; D010282:Parathyroid Neoplasms / Q000378:metabolism / Q000473:pathology
C506150:CHGA protein, human; D053379:Chromogranin A; D002864:Chromogranins; D019394:Ki-67 Antigen; D010281:Parathyroid Hormone