Affiliations 

  • 1 Universiti Sains Malaysia
MyJurnal

Abstract

Introduction: Resistance towards treatment is one of the challenges in breast cancer therapy. Recent studies show the link between lipoprotein with cancer resistance and progression. Clinical data indicates that oxidized low-density lipoprotein (oxLDL) and very low-density lipoprotein (VLDL) play roles the progression of breast cancer. Therefore, purpose of this study was to determine the roles of lipoproteins on migration of breast cancer cell and compare the effects of oxLDL and VLDL. Methods: Parent MCF-7 cells were purchased from ATCC, while the Tamoxifen-resistant MCF-7 (Tam-R MCF-7) was developed by pulse treatment method. Tam-R cells were treated with gradual increase in tamoxifen concentration for 72 hours in Dulbecco’s Modified Eagle’s medium (DMEM) without phenol red. Cell vi- ability test was done to measure the fold changes of Tam-R MCF-7 cells. Migration characteristics was studied using wound healing assay. Cells were treated with 10 μg/mL of oxLDL and VLDL up to 72 hours. Results: From the cell viability test, Tam-R MCF-7 cells had 4-fold increase of resistance than parental cells. Tam-R MCF-7 had acquired resistance to Tamoxifen and achieved a clinically relevant level of resistance. Lipoproteins were found to cause morphological changes, where cells exhibited elongation and dendritic-like growth compared to control cells. Both MCF-7 parental cells and Tam-R MCF-7 cells showed higher percentage of wound closure when treated with oxLDL. In contrast, VLDL treatment caused reduction in cell migration compared to oxLDL. Conclusion: Findings suggest that oxLDL may further promote resistant breast cancer cell migration compared to VLDL.