Acute Monocytic Leukemia (AML) is the most common myeloid leukemia, accounting for ~25% of adult and 15-20% of childhood leukaemia in the Western world. The average incidence of AML is 1 - 3 per 100,000 individuals, except in the United States and Australia, where it is 2 - 6 per 100,000. Current treatment of AML is aggressive and can include chemotherapy and bone marrow transplant or peripheral blood stem cell transplant. Within 2 years of remission, ~75% of patients have a recurrence, and aggressive therapy is re-initiated. Many AML patients die of their disease, primarily because of persistent or relapsed AML. Novel action therapeutic agents are needed. Our laboratory has compounds isolated from Australian marine sponges. We screened two purified compounds from Aplysilla rosea (a South Australian marine sponge) for their anticancer activities towards a human Acute Monocytic Leukemia cell line (THP-1) and a control non-cancer derived human lymphoblastoid cell line (WIL2-NS). The MTT colourimetric assay was run in 96-well microplates and used to screen for cell killing following treatment of THP-1 or WIL2-NS for 24h with 5 concentrations of each compound (167 µg/ml, 16.7 µg/ml, 1.67 µg/ml, 0.167 µg/ml and 0.0167 µg/ml). Data will be presented exploring the differential sensitivity of the two cell lines. Although, relative survival of both cell lines decreased at the highest concentrations for one of the compounds. One compound at lower concentrations is showing a greater decrease in relative survival in for the AML cell line than the lymphoblastoid cell line. The full data set will be presented at the conference.