The inhibitor had divergent effects on AML cell proliferation during coculture with chemokine-releasing MSCs; for one patient, growth inhibition was seen (median proliferation corresponding to 9,457 vs. 3,502 cpm), for three other patients, increased proliferation was observed (21,323 vs. 26,253 cpm, 10,934 vs. 19,713 cpm, and 55,257 vs. 74,956 cpm, respectively), and for the last patient, only a minor effect of CCL28 was seen (4,800 vs. 4,392 cpm) in the cocultures. The gene discussed is CCL28; the disease is acute myeloid leukemia.