Trans-10,cis-12, not cis-9,trans-11, conjugated linoleic acid decreases ErbB3 expression in HT-29 human colon cancer cells

Figure 1 Trans-10,cis-12 (t10c12) CLA abrogates the growth stimulatory effect of heregulin (HRG )-β. HT-29 cells were plated in 24-well plates at 50000 cells/well in DMEM/F12 supplemented with 10% fetal bovine serum. A day later, the monolayers were serum-starved with serum-free DMEM/F12 supplemented with 5 μg/mL transferrin, 0.1 mg/mL BSA, and 5 ng/mL selenium for 24 h. After serum-starvation, cells were incubated in serum-free medium in the absence or presence of 4 μmol/L t10c12 (A) or c9t11 (B) with or without 20 ng/mL HRG-β. Cell numbers were estimated by the MTT assay. Each bar represents the mean±SE (n = 6). Comparisons between groups that yielded significant differences are indicated by different letters above each bar. For example, ^aP<0.05 vs 0 μmol/L t10c12, ^cP<0.05 vs 0 μmol/L t10c12 + HRGβ, ^eP<0.05 vs 4 μmol/L t10c12.