Molecular analysis of the protein tyrosine phosphatase gamma gene in human lung cancer cell lines
Tsukamoto, T.; Takahashi, T.; Ueda, R.; Hibi, K.; Saito, H.; Takahashi, T.
Cancer Research 52(12): 3506-3509
1992
ISSN/ISBN: 0008-5472 PMID: 1596910 Document Number: 404333
The protein tyrosine phosphatase .gamma. (PTP-.gamma.) gene has recently been suggested as a candidate tumor suppresor gene involved in the oncogenesis of human lung and renal cancers, although no direct evidence for PTP.gamma. mutations has been demonstrated thus far. We explored the status of PTP.gamma. in 31 human lung cancer cell lines as well as in various other types of human tumor cell lines. Northern blot analysis revealed that two independent cell lines expressed PTP.gamma. mRNAs with sizes distinct from those in human fetal and adult normal lung. However, our extensive search for mutations in the PTP.gamma. gene failed to identify any abnormalities in the cytoplasmic region, which contains two protein tyrosine phosphatase-like domains. These results warrant further examination of genetic alterations in the extracellular and transmembrane domains of PTP.gamma., which had not been cloned at the time of the present study.