Identification of two genes differentially expressed upon different spatial configuration of the MGH-U3 human bladder cancer cells

By using mRNA differential display technology, we have compared gene expression in neoconfluent (actively proliferating) and 14-day confluent (non-proliferative) MGH-U3 cells. Two clones (6.17.6 and 10.9.2) displayed significantly increased expression in the 14-day confluent MGH-U3 cells, as confirmed by Northern blot analysis. Nucleotide sequence showed that clone 6.17.6 was part of the human insulin-like growth factor binding protein-5 (IGFBP-5) cDNA, while clone 10.9.2 was part of a human gene with unknown function (clone HSI12602). The differential IGFBP-5 expression in this model system was also evidenced by Western analysis. The possible anti-proliferative role of IGFBP-5 in this model system is briefly discussed.