To explore the expression spectra of apoptosis-related gene pnas-2 in normal tissues and acute leukemia (AL) patient tissues, the expressions of pnas-2 gene in tissues including heart, brain, placenta, lung, liver, skeletal muscle, kidney, pancreas, spleen, lymph node, thymus, leukocyte, bone marrow and fetal liver were detected by Northern blot. The expressions of pnas-2 in samples including 44 de novo, 9 non-CR, 27 CR and 12 relapsed AL patients were measured by real-time RT-PCR and Northern blot, and the expression levels of pnas-2 in normal and tumor tissues from 31 patients with malignancies were also detected. The results showed that pnas-2 was not expressed in the most tissues except in placenta. The results of real-time PCR indicated that pnas-2 expressions in samples of de novo, non-CR and relapsed patients ware significantly higher than that in CR, tumor tissues and normal tissues. In serial monitoring of 7 AL patients, the expression level of pnas-2 was high at first visit examination, but remarkably decreased after remission, and the pnas-2 expression level increased again when relapsed. It is concluded that the pnas-2 is specifically up-regulated in acute leukemia patients, which might be an oncogene and participate in leukemogenesis.