Anticancer Properties of Essential Oils and Other Natural Products

Table 2

In vitro studies of essential oils in combination with conventional chemotherapy agents.

Cell lines	Chemotherapy drug used alone and concentration	EO constituent used alone and concentration	Combined EO and chemotherapy drug		Reference
Prostate cancer cell (DU-145)	Docetaxel IC50 2.8 nM	d-limonene IC50 2.8 mM	IC50 docetaxel 1.9 mM and d-limonene 0.2 mM		[22]
Human breast cancer (MCF-7)	Paclitaxel 0.025 µg/mL^−1 resulted in 28% cell growth inhibition	β-caryophyllene resulted in no inhibition of cell growth	β-caryophyllene 2.5 µg/mL^−1 and Paclitaxel 0.025 µg/mL^−1 resulted in 50% cell growth inhibition	β-caryophyllene 10 µg/mL^−1 and Paclitaxel 0.025 µg/mL^−1 resulted in 68% cell growth inhibition	[23]
Human colorectal adenocarcinoma (DLD-1)	Paclitaxel 0.025 µg/mL^−1 resulted in 17.3% cell growth inhibition	β-caryophyllene resulted in no inhibition of cell growth	β-caryophyllene 2.5 µg/mL^−1 and Paclitaxel 0.025 µg/mL^−1 resulted in 91% cell growth inhibition	β-caryophyllene 10 µg/mL^−1 and Paclitaxel 0.025 µg/mL^−1 resulted in 189% cell growth inhibition	[23]
Mouse fibroblast (L-929)	Paclitaxel 0.025 µg/mL^−1 resulted in 18.4% cell growth inhibition	β-caryophyllene resulted in no inhibition of cell growth	β-caryophyllene 2.5 µg/mL^−1 and Paclitaxel 0.025 µg/mL^−1 resulted in 36% cell growth inhibition	β-caryophyllene 10 µg/mL^−1 and Paclitaxel 0.025 µg/mL^−1 resulted in 123% cell growth inhibition	[23]