Attempts to find out the exact biology of a special type of blood cancer called Acute Promyelocytic Leukemia (APL) went in vain till last month when two groups of researchers from both sides of the Atlantic tasted success. Their findings, published in a recent issue of the journal 'Nature', clearly show the mechanism behind the disease and also indicate the possible curative approach. The scientists have identified a particular cluster of cells called Histone Deacetylase Complex (HDAC), inhibition of whose activities have a positive bearing on the treatment of the disease.Two teams from the Salk Institute of Biological Studies, California and Perugia University (Italy), have suggested pharmacological manipulation of those cells or that of a specific inhibitor called Trichostatin-a (TSA) is a viable approach to the treatment of human leukemia.