Establishment of a mini-gene expression database for bladder tumor.
OBJECTIVE
Transitional cell carcinoma has been diagnosed mostly in urinary bladder in southern Taiwan and has an exceptionally high mortality rate. To identify the genes associated with bladder cancer, we investigated differential gene expression. Six bladder tumor cDNA libraries were constructed and their sequences were compared and analyzed.


METHODS
mRNA from bladder tumor cell lines or tissue samples were used to construct two regular cDNA libraries and four subtractive cDNA libraries after subtractive hybridization with cDNA derived from normal bladder epithelial cells. Subsequently, more than 100 cDNA inserts from each library were randomly isolated and sequenced, followed by sequence comparisons with nucleotide and protein sequence databases.


RESULTS
After searching the Basic Local Alignment Search Tool (Blast) databases, the cDNA nucleotide sequences were grouped into novel, known, and common gene categories. Since tumor nucleotide sequences are informative and valuable for research, they were organized as a mini-gene expression database (http://bladder.nhri.org.tw/). Interestingly, in one subtractive cDNA library, the ATPase 6 gene was found to be highly expressed in normal bladder epithelial cells and elevated levels of ATPase 6 mRNA were later confirmed by reverse transcription-polymerase chain reaction. However, the role of ATPase 6 in bladder tumorigenesis remains to be investigated.


CONCLUSIONS
The establishment of this database is an important step to enable systematic screening for bladder tumor-associated genes and may also be useful in developing diagnostic and/or therapeutic applications.
Li
Ching
C
Institute of Molecular Medicine, National Cheng Kung University Medical College, Tainan.
Chen
Chin-Chuan
CC
Yang
Te-Hsun
TH
Tzai
Tzong-Shin
TS
Huang
Chia-Hui
CH
Liou
Ji-Tzung
JT
Su
Ih-Jen
IJ
Tzeng
Ching-Cherng
CC
Chiu
Allen W
AW
Shieh
Biehuoy
B
D000251:Adenosine Triphosphatases / Q000235:genetics; D002295:Carcinoma, Transitional Cell / Q000235:genetics* / Q000401:mortality; D004273:DNA, Neoplasm / Q000235:genetics*; D015723:Gene Library; D006801:Humans; D008928:Mitochondria / Q000201:enzymology; D025261:Mitochondrial Proton-Translocating ATPases; D013624:Taiwan / Q000453:epidemiology; D014407:Tumor Cells, Cultured; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000401:mortality
D004273:DNA, Neoplasm; C501005:MT-ATP6 protein, human; D000251:Adenosine Triphosphatases; D025261:Mitochondrial Proton-Translocating ATPases