Aim: In the current in vitro study, we tried to examine the possible role of
resveratrol as a sensitizer in combination with radiotherapy or hyperthermia.
Background: Breast cancer is the most common malignancy for women and one of the most
common worldwide. It has been suggested that using non-invasive radiotherapy alone
cannot eliminate cancer cells. Hyperthermia, which is an adjuvant modality, induces cancer
cell death mainly through apoptosis and necrosis. However, cancer cells can also develop
resistance to this modality.
Objective: The objective of this study was to determine possible potentiation of apoptosis
when MCF-7 cells treated with resveratrol before hyperthermia or radiotherapy.
Methods: MCF-7 cancer cells were treated with different doses of resveratrol to achieve
IC50%. Afterwards, cells treated with the achieved concentration of resveratrol were exposed
to radiation or hyperthermia. Proliferation, apoptosis and the expression of pro-apoptotic
genes were evaluated using flow cytometry, MTT assay and real-time PCR. Results for each
combination therapy were compared to radiotherapy or hyperthermia without resveratrol.
Results: Both irradiation or hyperthermia could reduce the viability of MCF-7 cells.
Furthermore, the regulation of Bax and caspase genes increased, while Bcl-2 gene
expression reduced. Resveratrol potentiated the effects of radiation and hyperthermia on
Conclusion: Results of this study suggest that resveratrol is able to induce the regulation of
pro-apoptotic genes and attenuate the viability of MCF-7 cells. This may indicate the
sensitizing effect of resveratrol in combination with both radiotherapy and hyperthermia.