p27(kip1) and Other Cell-Cycle Protein Expression in Normal and Neoplastic Endocrine Tissues.

Endocrine tumors are often diagnostic challenges. Recent studies have suggested that proteins that regulate cell cycle may have diagnostic and prognostic utility in endocrine tumors. p27(kip1) (p27) is a cyclin-dependent kinase inhibitor that regulates the transition from the G1 to the S phase of the cell cycle.

Neoplasms Causing Nonhyperinsulinemic Hypoglycemia.

Non-islet cell tumor hypoglycemia (NICTH) is uncommon. Many of the tumors associated with NICTH are mesenchymal tumors, although carcinomas are also involved in some cases. High serum levels of insulin-like growth factor II (IGF-II) have been associated with NICTH.

Analysis of TGF-B and TGF-B-RII in Thyroid Neoplasms from the United States, Japan, and China.

Transforming growth factor B (TGF-B) has an inhibitory effect on cell proliferation in various cells and tumors, so loss of TG-B-receptor (TGF-B-R) may lead to increase proliferative activity in these tumors. We compared the expression of TGF-B and TGF-B-Rll in a group of thyroid neoplasms from the United States, Japan, and China to determine if there were differences in the expression of this growth factor or its receptors in various tumor types from different countries. A total 108 neoplastic thyroids from the United States, 42 from Japan, and 46 from China were analyzed for TGF-B1, TGF-B3, and TGF-B-Rll by in situ hybridization with riboprobes.

Oxyphil parathyroid carcinomas: a clinicopathologic and immunohistochemical study of 10 cases.

Oxyphil parathyroid carcinomas are uncommon neoplasms, and the clinicopathologic features of these tumors are largely unknown. We evaluated the clinicopathologic features of oxyphil parathyroid carcinomas and the expression of cytokeratin 14 (CK14), the high-affinity glucose transporter-4 (Glut-4), as well as the cell cycle proteins p27 and Ki67 and compared these with oxyphil parathyroid adenomas and chief cell parathyroid adenomas and carcinomas. Formalin-fixed, paraffin-embedded archival tissues from primary (n = 6) and recurrent (n = 4) oxyphil carcinomas were analyzed and compared with chief cell parathyroid carcinomas (n = 12), oxyphil parathyroid adenomas (n = 38), and chief cell parathyroid adenomas (n = 17) by immunohistochemistry for CK14, Glut-4, p27, and Ki67 using the avidin-biotin peroxidase system.