In this study, resveratrol-loaded solid lipid nanoparticles (Res-SLNs) were successfully designed to treat MDA-MB-231 cells. The Res-SLNs were prepared using emulsification and low-temperature solidification method. The Res-SLNs were spherical, with small size, negative charge, and narrow size distribution. Compared with free resveratrol, the Res-SLNs displayed a superior ability in inhibiting the proliferation of MDA-MB-231 cells. In addition, Res-SLNs exhibited much stronger inhibitory effects on the invasion and migration of MDA-MB-231 cells. Western blot analysis revealed that Res-SLNs could promote the ratio of Bax/Bcl-2 but decreased the expression of cyclinD1 and c-Myc. These results indicate that the Res-SLN may have great potential for breast cancer treatment.

Background MicroRNAs (miRNAs) are a class of small, non-coding RNAs that functioned by targeting specific mRNA. Many studies have reported that, miRNAs play a vital role in cancer progression, they can exert their functions as oncogenes or cancer suppressors. As suggested in previous report, miR-155-5p is up-regulated in breast cancer. Results Here, we found that miR-155-5p promoted cell proliferation and inhibited cell apoptosis in MCF-7. In addition, these effects were reversed when high levels of miR-155-5p were suppressed in MCF7/PR. We determined that TP53INP1 served as a direct target of miR-155-5p through bioinformatic and luciferase assay. These findings confirmed that miR-155-5p was a tumorigenic factor that acted by targeting TP53INP1 and promoted tumor progression and contributed paclitaxel resistance to chemotherapy. Conclusions These results contribute to our understanding of the molecular mechanism underlying breast cancer progression and resistance to chemotherapy.