CTSK and acute myeloid leukemia: Feature plots of ACTA2+ AML cells showed selective expression of known LAM and AML markers, including ACTA2, PMEL, FIGF, and CTSK, and several key sphingolipid pathway genes, including ASAH1, DEGS1, SPHK1, and SPHK2, were selectively expressed in the same ACTA2+ AML cell cluster (Figure 1H).