Aberrant prothymosin-alpha expression in human bladder cancer.
OBJECTIVE
To investigate the prothymosin-alpha (PTMA) expression in human bladder cancer using tissue microarrays.


METHODS
Two tissue microarray slides of 50 bladder tumors and 42 paired normal adjacent tissues were investigated using immunohistochemical staining. The staining distribution was categorized as negative, nuclear, cytoplasmic, and mixed expression. Quantitative immunoreactivity was measured using image analysis, as represented by the integrated optical density for each tissue core.


RESULTS
In 36 of 42 normal adjacent tissues, positive PTMA immunoreactivity could be seen in some nuclei of the normal urothelial cells, but not, or only minimally, in the cytoplasm and underlying submucosal tissues. A statistically significant enhancement of PTMA expression was found in bladder tumors of each grade compared with the normal adjacent tissue (P < .0001 for normal adjacent tissues vs grade 1, 2, or 3 tumors, paired t test). Of 48 transitional cell carcinoma specimens, only 4 (8.3%) were graded as negative and 44 (91.7%) were positive for PTMA expression, including nuclear (n = 8), cytoplasmic (n = 12), and mixed expression (n = 24) patterns. A statistically significant correlation was found between high grade and mixed expression (P = 0.0020, chi(2) test).


CONCLUSIONS
Increased PTMA expression was found in human bladder cancers compared with the paired normal adjacent bladder tissue. The distribution of PTMA expression was changed in high-grade tumors. The clinical significance of such an aberrant PTMA expression in bladder cancer is worthy of additional investigation.
Tsai
Yuh-Shyan
YS
Institute of Clinical Medicine, University Hospital and Douliou Branch, National Cheng Kung University College of Medicine, Tainan, Taiwan.
Jou
Yeong-Chin
YC
Lee
Gia-Fong
GF
Chen
Yeong-Chang
YC
Shiau
Ai-Li
AL
Tsai
Hsin-Tzu
HT
Wu
Chao-Liang
CL
Tzai
Tzong-Shin
TS
D006801:Humans; D046228:Microarray Analysis; D011498:Protein Precursors / Q000032:analysis / Q000096:biosynthesis*; D013947:Thymosin / Q000031:analogs & derivatives* / Q000032:analysis / Q000096:biosynthesis; D001749:Urinary Bladder Neoplasms / Q000737:chemistry / Q000378:metabolism*
D011498:Protein Precursors; C040782:prothymosin alpha; D013947:Thymosin