Positive cyclin T expression as a favorable prognostic factor in treating gastric gastrointestinal stromal tumors.
Positive transcriptional elongation factor b (P-TEFb) contains the catalytic subunit cyclin-dependent kinase 9 (Cdk9) and the regulatory subunit cyclin T. Cyclin T1 and Cdk9 are the key factors of the PTEFb pathways and are overexpressed in the human head and neck carcinoma cell line. However, there have been limited studies regarding the role of cyclin T1 and Cdk9 in gastric gastrointestinal stromal tumors (GISTs). The aim of the present study was to assess the association between cyclin T1 and Cdk9 and their clinical significance in gastric GISTs. A total of 30 gastric GIST patients who underwent either laparoscopic or laparotomic partial gastrectomy were enrolled in the study. The surgical tissue slides were stained with Cdk9 and cyclin T1 antibodies, and the immunohistochemistry scores and disease-free survival (DFS) were analyzed. Ten patients were cyclin T1-positive, and 20 were negative. All 11 patients with recurrent tumors or distant metastases were cyclin T1-negative patients. Old age, large tumor size, a high Ki67 IHC staining score, high mitotic count and negative cyclin T1 staining revealed a worse clinical outcome in univariate analysis. By contrast, the Cdk9 score was not associated with clinical parameters. The Kaplan-Meier survival curve illustrated that the DFS rate of the patients with negative cyclin T1 staining was significantly lower than that of the patients with positive cyclin T1 staining. Positive expression of cyclin T1 was a good prognostic factor in patients with gastric GISTs.
Division of Gastroenterology, Department of Internal Medicine, Tungs' Taichung MetroHarbor Hospital, Taichung 435, Taiwan R.O.C.
Lien-Fu
LF
Lin
Department of Pathology, Tungs' Taichung MetroHarbor Hospital, Taichung 435, Taiwan R.O.C.
Jong-Shiaw
JS
Jin
Department of Applied Chemistry, National Chia-Yi University, Chia-Yi 600, Taiwan R.O.C.
Jui-Chang
JC
Chen
Center of Nano Bio-Detection, National Chung Cheng University Chia-Yi, Chia-Yi 621, Taiwan R.O.C.
Chia-Chi
CC
Huang
Department of Applied Chemistry, National Chia-Yi University, Chia-Yi 600, Taiwan R.O.C.
Jeng-Horng
JH
Sheu
Department of Applied Chemistry, National Chia-Yi University, Chia-Yi 600, Taiwan R.O.C.
Wenlung
W
Chen
Department of Pathology, Tungs' Taichung MetroHarbor Hospital, Taichung 435, Taiwan R.O.C.
Tang-Yi
TY
Tsao
Department of Applied Chemistry, National Chia-Yi University, Chia-Yi 600, Taiwan R.O.C.; Division of General Surgery, Department of Surgery, Tungs' Taichung MetroHarbor Hospital, Taichung 435, Taiwan R.O.C.
Chih-Wei
CW
Hsu
cyclin T1; cyclin-dependent kinase 9; disease-free survival; gastric gastrointestinal stromal tumor