<i>In Vitro</i> Assessment of Silybin-Doxorubicin HCl Combination Therapy for Breast Cancer

Background: This study focuses on the assessment of the antitumor potential of a combination of doxorubicin hydrochloride and silybin for the treatment of breast cancer. Method: Spectrophotometric analysis, Fourier-transform infrared (FTIR) spectroscopy, and differential scanning calorimetry (DSC) were used to assess the physicochemical characteristics of drugs and their combination. The calibration curve of both drugs obeyed Beer-Lambert’s law. Further spectrophotometric analysis validated the quantification method by confirming the linearity of calibration curves. There were no notable changes in the distinct functional groups observed in the FTIR spectra, suggesting the absence of any chemical interactions. A shifted peak in the drug mixture indicated interaction without degradation, while DSC thermograms showed distinctive thermal transitions. Antiproliferative effects were assessed using cytotoxicity tests on MCF-7 breast cancer cell lines. Results: The silybin-to-doxorubicin mixture in a 2:1 ratio produced the strongest total growth inhibition (TGI = 40 µg/mL) in cytotoxicity tests, which showed modest antiproliferative action. Cellular changes produced by drug concentrations and various ratios were evaluated using morphological analysis, which revealed a concentration-dependent cytotoxic effect. Conclusion: A moderate anticancer activity of a combination of silybin and doxorubicin hydrochloride shows a future direction for continued study.