Comprehensive Analysis of the Chemical Composition and In Vitro Cytotoxic Mechanisms of Pallines Spinosa Flower and Leaf Essential Oils Against Breast Cancer Cells

Abstract

Background/Aims: In our quest for new natural anticancer agents, we studied the cytotoxicity of the essential oils extracted from flowers and leaves of Pallines spinosa. Methods: The essential oils were extracted by hydrodistillation and solid phase microextraction (SPME) from flowers and leaves of the plant and their composition was determined by GC/GC-MS. The cytotoxicity of the oils was evaluated against MCF-7 and MDA-MB-231 breast adenocarcinomas, and the non-cancerous MCF-10-2A cells, using a flow cytometry-based assay Apoptosis was evaluated by flow cytometry, nuclear staining, caspases activation, and Western blotting techniques, and cell cycle by measuring DNA contents. Results: The hydrodistilled flower oil contained mainly sesquiterpenes (96.39%), while the leaf sample was dominated by oxygenated-sesquiterpenes (51.60%) and sesquiterpene-hydrocarbons (34.06%). In contrast, the SPME oil contained mainly monoterpene-hydrocarbons (44.09%) and sesquiterpene-hydrocarbons (34.15%) in the flower and leaf samples, respectively. The cytotoxicity of the flower oil against MCF-7 (IC₅₀ 0.25 ± 0.03 µg/mL) and MDA-MB-231 (IC₅₀ 0.21 ± 0.03 µg/mL) was much stronger than the leaf oil (IC₅₀ 2.4 ± 0.5 µg/mL and 1.5 ± 0.1 µg/mL, respectively). The toxicity of the flower oil was ∼5 to 8-times less in normal MCF-10-2A (IC₅₀ 1.3 ± 0.2 µg/mL) and blood mononuclear cells (2.80 ± 0.45 µg/mL) as compared to breast and hematological cancer cells, respectively. Both oils induced a caspase-dependent and -independent apoptosis in MCF-7 and MDA-MB-231 cells, and altered the levels of Bcl-2 and Bax proteins. In addition, the oils arrested cell cycle in both cancer cell lines at G0/G1 phase by modulating the expression of cyclin D1, CDK4 and p21 proteins. Conclusion: The cytotoxicity of P. spinosa oils were mediated by apoptosis and cell cycle arrest, suggesting the potential use of their bioactive compounds as natural anticancer compounds.

Essential Oils’ Potential in Breast Cancer Treatment: An Overview

“…The L-PSEO was composed of 51.60% of oxygenated STs and 34.06% of SQ hydrocarbons. F-PSEO had stronger anticancer results for MCF7 and MDA-MB-231 and both EOs induced a caspase-dependent and caspase-independent apoptosis and altered the levels of Bcl-2 and Bax proteins [46].…”

Flowers for cancer treatment: From beauty to duty

“…Thus, the ethanolic FE of Thevetia peruviana stimulated apoptosis of cervical cancer HeLa cells triggered by TNFα or TRAIL, two ligands of death receptors, by activating caspase-3 and PARP. Notably, FE of T. peruviana diminished the expression of the anti-apoptotic protein survivin (Managit, Sakurai, and Saiki, 2017) A FE containing essential oils of Pallines spinosa decreased cell viability of breast cancer cells while a minor effect was detected in immortalized mammary epithelial cells (Saleh et al, 2017). This effect was accompanied by a decrease of the anti-apoptotic protein Bcl-2 and an increase of the pro-apoptotic protein Bax Flowers from Antirrhium majus are among the most popular edible flowers, frequently used from preparing foods and drinks.…”

Chemical composition and biological activities of the essential oils from Vitex-agnus castus, Ocimum campechianum and Ocimum carnosum

“…Plants essential oils can be used as alternative sources of Ae. aegypti larval control agents (Aguiar et al 2010, Gois et al 2011, Dias & Moraes 2014, Pavela 2015, Carvalho et al 2016, De Sousa et al 2016, Mendes et al 2017, Nascimento et al 2017, Mar et al 2018, and have been reported to show cytotoxic activity when tested on human cancer cell lines (Gautam et al 2014, Lesgards et al 2014, De Sousa et al 2016, Kumar et al 2016, Saleh et al 2017, Tavakoli et al 2017, Vasilijevic et al 2018.…”