Identification of differentially expressed genes in lung tissues of nickel-exposed rats using suppression subtractive hybridization.

Occupational exposure to nickel compound, such as nickel refining, electroplating, and in conjunction with other metals, is harmful to the health, causing respiratory distress, and lung and nasal cancer. In this work, the different gene expression patterns of lung tissues from nickel-exposed rats and controls were investigated. The suppression subtractive hybridization (SSH) method was used to generate two subtracted cDNA libraries with gene transcripts differentially expressed after nickel inducing. Dot-blot hybridizations were used to confirm differential ratios of expression of obtained SSH clones. Out of 768 unique SSH clones, which were chosen randomly from the two subtraction libraries (384 of each), 319 could be verified as differentially expressed. According to blast screening and functional annotation, 28% genes in nickel-induced cDNA library were related to cell differentiation, whereas 21% in driver library were related to oxygen transport. Two novel expressed sequence tags (ESTs; NCBI Accession No. FC809414 and No. FC809411) in nickel-induced cDNA library were obtained. The genes detected in the present study are probably important genes associated with nickel-induced lung cancer.