Figure 2.

25-HC decreases the sensitivity of GC cells to 5-FU. (A) AGS cells and MGC-803 were treated with 25-HC with or without 5-FU (5 µM) for 24 and 48 h and cell proliferation was determined by CCK-8 assay. The absorbance at 450 nm was measured on an ultra-microplate reader. (B) Nude BALB/c mice were injected subcutaneously with AGS cells at 5×10⁶/mouse. When the volumes of tumors reached 100 mm³, the mice were intraperitoneally injected with 5-FU (25 mg/kg) or/and 25-HC (10 mg/kg) every 3 days for 3 weeks. Xenograft tumors were stripped from the nude mice and imaged or tumor weights and tumor volumes were assessed after sacrifice. Results were obtained from 3 independent experiments and are expressed as the means ± SEM. Statistical significance in (A and B) was determined by one-way ANOVA followed by Dunnett's test and Tukey's test, respectively; ^*P<0.05, ^**P<0.01 and ^***P<0.001. 25-HC, 25-hydroxycholesterol; GC, gastric cancer.