Antiproliferative activity of the combination of doxorubicin/quercetin on MCF7 breast cancer cell line: A combined study using colorimetric assay and synchrotron infrared microspectroscopy

Breast cancer is the most common type of cancer among females worldwide. Doxorubicin (Dox) is one of the main chemotherapy drugs used in neoadjuvant and adjuvant breast cancer therapy. Dox-induced cardiotoxicity limits its use to a definite period and a definite cumulative dose. On the other hand, quercetin (Quer), a natural antioxidant, has been successfully reported to protect cardiomyocytes from Dox toxicity. Our aim is to optimize Dox regimen by assessing Quer effect on Dox cytotoxicity in a breast cancer cell model, MCF7 using a classic in vitro technique as well as Fourier Transform Infrared (FTIR) microspectroscopy. The cancer cells were exposed to Dox, Quer, or the combination of both agents for 72 incubation hours. Cell proliferation was assessed by using the classical colorimetric Sulforhodamine B (SRB) assay and JC1 dye. MCF7cells were further investigated by FTIR microspectroscopy to correlate SRB results with the changes in the distinctive IR spectra of the cells. Our results show that Quer exerts an antiproliferative effect and enhances the cytotoxicity of Dox in MCF7 cells. Results obtained from both the in vitro assays and FTIR microspectroscopy showed that Quer potentiates the effect of Dox in breast cancer cells.