Effect of red laser irradiation and Ajwain essential oil on 2D and 3D culture models of MDA-MB-231 breast cancer cells

Cancer is the second leading cause of death after cardiovascular disease in many societies. One of the traditional methods to control the progression of cancers is chemotherapy, which is often associated with severe complications. Research shows that medicinal plants are an excellent and reliable source for the development of new anticancer drugs. In the present study, the effect of Trachyspermum ammi or Ajwain essential oil (AEO) alone and in combination with low-level laser on 2D and 3D culture of MDA-MB-231 breast cancer cells was investigated. 2D and 3D culture of MDA-MB-231 breast cancer cells were treated with different concentrations of AEO (0 to 100 mu g/mL) for 24 h and low-level laser irradiation at 660 nm and 3 J/cm(2) for 90 s by three methods: (1) treatment with AEO alone, (2) treatment with AEO and then low-level laser irradiation and (3) treatment with low-level laser irradiation and then AEO. The effect of AEO and low-level laser on cell survival, cell morphology changes, and the occurrence of apoptosis was investigated using MTT, light microscopy, and fluorescence microscopy, respectively. The effective concentration (IC50) of AEO in both 2D and 3D cultures of MDA-MB-231 cells was obtained at 35 mu g/mL. Data from the MTT test showed that MDA-MB-231 cells were not destroyed by low-level laser irradiation alone, and also by combination therapy when the cells were first treated with AEO and then exposed to the low-level laser causes more mortality than AEO alone. Images obtained by light microscopy and fluorescence microscopy also confirmed higher cell mortality in the combined method of cell treatment with AEO and then low-level laser. This study showed that in addition to several medicinal properties mentioned in other studies, AEO also has anti-cancer effects, and also a combination treatment of AEO and low-level laser increases the anticancer effects of AEO and further reduces survival of MDA-MB-231 breast cancer cells. Investigation of the anti-cancer effects of AEO and its active ingredients in other cancer cells as well as animal models of tumors are suggested in future studies.