Background & objective: A novel membrane-associated gene CT120 was isolated from chromosome 17p13.3 locus in our laboratory. Its mRNA was not expressed in human normal lung tissues, but was abundant in human lung cancer cell line SPC-A-1. This study was designed to investigate the differential expression patterns of CT120 in different lung cancer and noncancerous tissues using immunohistochemistry and to explore the effects of ectopic expression and overexpression of CT120 on cell growth in vitro and in vivo.
Methods: A polypeptide at the C-terminus of CT120 was selected by bioinformatics, then was synthesized and conjugated to KLH (a high molecular carrier). The chicken anti-CT120 antibody IgY was prepared with the synthesized antigen and was used to determine the different expression patterns of CT120 in various tumor cell lines and in lung cancer and noncancerous tissues. The effects of ectopic expression of CT120 on NIH/3T3 cell growth were investigated through colony formation analysis. The effect of overexpression of CT120 on the cell growth of A549 was analyzed using growth curve assay and tumor formation assay of transfected cells in nude mice.
Results: The novel gene CT120 expressed in various tumor cell lines and expressed remarkably higher in lung cancers than in noncancerous tissues as well as normal lung tissues. Also, it promoted the proliferation of NIH/3T3 and A549 cells in vitro and in vivo.
Conclusion: CT120 gene may be a novel candidate gene closely related to lung carcinogenesis.