Esophageal cancer is a common cancer among ethnic Chinese. The reported incidence of esophageal cancer has increased many fold in the past decades and is apparently still rising. Nuclear matrix forms the scaffold of the nucleus and participates in various nuclear functions. Cancer specific nuclear matrix proteins have been identified in several tumor systems. 2-D gel analysis shows the presence of novel nuclear matrix proteins in ATRA treated tumor cells and these proteins are cell line specific. Our preliminary study also shows ATRA altered the nuclear matrix density of tumor cells. The significance of these nuclear matrix proteins is discussed.