Antineoplastic activity of mitomycin C formulated in nanoemulsions-based essential oils on HeLa cervical cancer cells

Combining the essential oils (ESSOs) with the chemotherapeutic agent, mitomycin C (MMC), in nanoparticle can be beneficial in cancer therapy. The aim of the current study was to in vitro evaluate the antineoplastic effect of MMC, formulated in two different nanoemulsions (NE) based on two ESSOs, chamomile (Ch) and garlic (Gar), on HeLa cervical cancer cells. The z-average diameter of Ch-NE has slightly increased from 83.39 ± 12.85 nm to 91.18 ± 5.79 nm when mixed with MMC (Ch-MMC) whereas the z-average diameter of Gar-NE has markedly increased from 50.6 ± 1.96 nm to 75.64 ± 7.13 nm when loaded with MMC (Gar-MMC). The zeta potentials of both of Ch-NE and Ch-MMC, which were -1.91 ± 4.38 mV and -5.44 ± 5.26 mV, respectively, have differed from Gar-NE and Gar-MMC, which were 11.4 ± 2.29 mV and 11.5 ± 2.28 mV, respectively. Compared to MMC solution, the cell viabilities of HeLa cells, measured by the MTT assay, were reduced 42 and 20 times when subjected into Ch-MMC and Gar-MMC, respectively. The light microscopy images revealed that the cell membrane of the HeLa cells treated with Gar-NE or Gar-MMC were more altered relative to the cells treated with Ch-NE or Ch-MMC. In contrast, the nuclei of the HeLa cells, stained with DAPI and treated with Ch-NE or Ch-MMC, were more fragmented than the cells treated with Gar-NE or Gar-MMC, indicating that both of Ch-NE and Ch-MMC have passed the cell membrane and affected the nucleus directly whereas Gar-NE and Gar-MMC have got attached to the cell membrane causing damage to the cell. In conclusion, combining MMC with NE-based ESSOs has increased the cytotoxic effect of the MMC on the HeLa cells with different mechanism of actions.