Cytotoxic effects of Ridolfia segetum (L.) Moris phytoproducts in cancer cells

Ethnopharmacological relevance: The past few years have witnessed an increasing interest in essential oils (EOs) as potential therapeutic agents against a wide variety of pathologies, including cancer. EOs extracted from Ridolfia segetum (L.) Moris (R. segetum) are a clear example of a phytoproduct with therapeutic applications, as it is widely used in traditional medicine due to its antioxidant and anti-inflammatory properties, and these properties were already validated by previous studies. Although, it is well established that inflammation is a key hallmark of cancer, with a key role promoting tumorigenesis, and being chronic inflammation often associated with tumorigenic processes, there are no previous studies regarding the assessment of the antitumoural potential of R. segetum EOs.

Aim of the study: The present study intends to be the first to evaluate the antitumoural proprieties of R. segetum EO phytoproducts in cancer cell models.

Materials and methods: For this, R. segetum EOs were extracted from plants collected at either flowering (RS_Fl) or fruiting (RS_Fr) stage. The impact on proliferation and viability of treatment with R. segetum EO extracts was assessed using in vitro 2D and 3D models.

Results: Both R. segetum EOs presented effective antiproliferative/viability effects, evidence noted by low IC₅₀ values in 2D models, and significant reduction of spheroid size in 3D in vitro models. Mechanistically, treatment with R. segetum EOs was associated with an altered G1 (associated with p21 stabilisation), and subsequent induction of apoptosis.

Conclusions: Overall, these results indicate that R. segetum EOs have potential as suitable antitumoural therapeutic agents.

Keywords: Antitumour activity; Essential oil; Natural products; Ridolfia segetum.