AML-MSC co-cultures increase Cox-2 in MSCs in an IL1β- and ARC-dependent manner. A. Cox-2 expression in MSCs (CD90+) and OCI-AML3 (CD45+) cells cultured alone or co-cultures, without or with IL1β (100 ng/ml) and/or ILIRA (100 ng/ml) treatments for 48 h. The upper panel is the histogram of one representative experiment and the lower panel is the results of 3 independent experiments with 3 different MSCs. B. Cox-2 expression in MSCs (CD90+) and primary patient samples (CD45+) (n = 3, Table 1, samples 1-3) cultured alone or co-cultures, without or with IL1β (25 pg/ml, 100 pg/ml, or 100 ng/ml) and/or ILIRA (100 ng/ml) treatments for 48 h. The same MSC was used for all three co-cultures. C. Cox-2 expression in MSC and OCI-AML3 cells by flow cytometry under MSCs co-cultured with control or ARC KD OCI-AML3 (left), control or ARC KD MSCs co-cultured with OCI-AML3 (center), or control or ARC KD MSCs co-cultured with control or ARC KD OCI-AML3 (right) for 48 h. Vec, vector control. Three independent experiments were performed.