An integrated technique for identification of differential genes expressed in patients with cancer.

To develop a method for identification of differential gene expression between different cell populations, several convenient techniques of molecular biology, including subtractive hybridization, suppression PCR, T/A cloning and sequencing, were used to identify genes expressed differentially in CD45+ and CD45- cells isolated from U266 cell line of multiple myeloma. Our results showed that the levels of abundant genes scale down 20 times through subtractive hybridization. Plasmid DNA from CD45- cell clones was hybridized with forward or backward cDNA probes synthesized from CD45- and CD45- cells, respectively. A few of differentially expressed genes reconfirmed by RT-PCR were identified from 500 expressed clones of CD45+ cells. It is concluded that a strategy for gene expression identification developed from conventional molecular biological methods can be used in different laboratories.