(A) Effect of JQ1 treatment (0.5 μM for 24 hr) on the phosphorylation level of PI3K pathway proteins including GSK3β (S9) in DLBCL and BL cell line panel, as determined by a luminex multiplex assay.
(B) Western blot confirming sustained effects of JQ1 on c-MYC, GSK3β (S9) and total GSK3β levels in TMD8 cells for up to 48 hr.
(C) Confirmatory western blots showing similar effects of JQ1 and CPI-203 (1 μM, 24 hr) on p-GSK3β S9, total GSK3β, and β-catenin levels in 2 BL cell lines (RAJI and CA-46). Numbers below β-catenin blots indicate fold-change of protein expression versus DMSO (normalized to the relative loading controls) evaluated by densitometry analysis using the ImageJ software.
(D) Nuclear-cytoplasmic fractionation experiments confirming increased nuclear β-catenin levels in ABC-derived DLBCL cell lines (TMD8, HBL-1) following treatment with BET inhibitors (JQ1 or CPI-203 0.5 μM for 24 hr). Vinculin and lamin B1 were used as loading controls for cytoplasmic and nuclear fractions, respectively. Numbers indicate fold-change of nuclear β-catenin protein expression versus DMSO (normalized to the relative loading controls), evaluated by densitometry analysis, using the ImageJ software. N, nuclear protein fractions; C, cytoplasmic protein fractions.
(E) Effect of JQ1 treatment (0.5 μM for 24 hr) on cytokine-chemokine levels as measured by a multiplex assay in 9 representative DLBCL cell lines of ABC and GCB origin (SUDHL-4, SUDHL-6, SUDHL-8, DB, BJAB, TMD8, HBL-1, and U2932), and 1 BL cell line (CA-46). As shown, JQ1 upregulated the PI3K-dependent chemokines MIP-1α and MIP1β mostly in ABC and BL cell lines. In some cell lines, cytokine levels were below detection. Results are shown as average fold change value of cytokine-chemokine concentration in cell culture supernatants (versus DMSO) of 3 independent experiments.
(F) Standard ELISA confirming significant MIP-1α upregulation in ABC-derived DLBCL cell lines (TMD8, HBL-1) and BL cell lines (CA-46) after treatment with JQ1 or CPI-203 0.5 μM for 24 hr. Error bars represent SEM of triplicate experiments. Differences between groups (JQ1 or CPI versus DMSO) were calculated with the Student’s t test. *p < 0.05, **p < 0.01. BD (below detection).