Down-regulation of the human PRL-3 gene is associated with the metastasis of primary non-small cell lung cancer.
BACKGROUND
Phosphatase of the regenerating liver (PRL)-3 protein tyrosine phosphatase gene is expressed in colon cancer metastasis. To investigate the role of this gene in metastatic lung cancer, we compared PRL-3 gene expression between primary cancers, metastatic lung cancer, and normal lung tissue.


METHODS
Five metastatic tumor and normal samples from non-small cell lung cancer patients were obtained at the National Hospital Organization Kumamoto Medical Center (Kumamoto, Japan). For a quantitative evaluation of RNA expression by PCR, we used Taqman PCR methods.


RESULTS
Although PRL-3 gene expression levels in the primary lesions were slightly decreased compared with those in the normal tissues, those in the metastatic lesions were extremely down-regulated in the synchronous metastatic case. In 2 of these 3 cases, the metastatic tumors showed down-regulated PRL-3 gene expression at 10 times less than that of the normal tissue, and the other tumor showed a slightly weaker expression.


CONCLUSIONS
These data suggest that a down-regulation of the PRL-3 gene is important in lung cancer metastasis and provide a new hypothesis of lung cancer metastases.
Yamashita
Shin-ichi
S
Department of Surgery, National Hospital Organization Kumamoto Medical Center, Kumamoto, Japan.
Masuda
Yoshiko
Y
Matsumoto
Katsutaka
K
Okumura
Yasuhiro
Y
Matsuzaki
Hosei
H
Kurizaki
Takashi
T
Haga
Yoshio
Y
Katafuchi
Shigeru
S
Murayama
Toshihiko
T
Ikei
Satoshi
S
Kawahara
Katsunobu
K
D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000556:secondary*; D015536:Down-Regulation; D015870:Gene Expression; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D009363:Neoplasm Proteins / Q000235:genetics*; D017027:Protein Tyrosine Phosphatases / Q000235:genetics*
D009363:Neoplasm Proteins; C484730:PTP4A3 protein, human; D017027:Protein Tyrosine Phosphatases