Fig. 5. SF1126 activates p38 signaling in CRC cells. HT-29 cells were treated with 5 μM SF1126 or LY294002 ("LY") plus JQ1 for 2h. Expression of listed proteins in total cell lysates were tested (A). HT-29 cells were pretreated for 30 min with 5 μM of SB203580 or SB239063, followed by the SF1126 treatment. Cell viability and apoptosis were tested by the MTT assay (B) and TUNEL fluorescence intensity assay (C), respectively. Stable HT-29 cells, with p38 shRNA ["sh-p38 (-1)/(-2)"] or scramble control shRNA ("sh-C"), were treated with 5 μM of SF1126 for 2h; listed proteins were shown (D). Cells were also cultured for 48 or 72h, and cell viability (E) and apoptosis (F) were tested. HT-29 cells, pretreated with SB203580 (5 μM) or with p38 shRNA ["sh-p38 (-1)"], were treated with 5 μM LY plus JQ1 for 72h, and cell viability was tested (G). The primary human colon cancer cells ("pri-Can-2") were treated with 5 μM SF1126 for 2h; expression of listed proteins are shown (H). Primary cancer cells were pretreated for 30 min with 5 μM SB203580 or SB239063, followed by 5 μM of SF1126 treatment for 72h; cell viability was tested (I). "DMSO" stands for 0.1% dimethyl sulfoxide. *p< 0.05 vs. the "C" group. ^# p< 0.05 vs. "SF1126" treatment in the "DMSO" group or in the "sh-C" group. The experiments were repeated three times, with similar results obtained.