Selective Inhibitory Effect of Cannabidiol from Cannabis Sp. Plants on Tumour Cell Proliferation

Cannabidiol is a non-psychoactive phytocannabinoid with growing interest as a potential antitumour agent in veterinary medicine due to its modulatory effects on cell proliferation and survival. The aim of this preliminary in vitro study was to evaluate the impact of cannabidiol on non-tumourigenic MCF-10A and tumourigenic MCF-7 breast cell lines using colorimetric measurement of metabolic activity (MTS assays) and the real-time cell analyser xCELLigence system (RTCA). Cannabidiol stimulated the metabolic activity of MCF-10A cells at all tested concentrations and time points, with maximal effects at 24 and 48 hours, while enhanced adhesion was observed after 72 hours. In contrast, MCF-7 cells showed a decrease in metabolic activity at 20 μM after 24 and 48 hours, alongside a consistent decrease in adhesion across all conditions, most pronounced at 48 hours. The Pearson correlation test revealed a strong positive correlation (r = 0.7768) between the MTS assay and xCELLigence system results. These findings suggest the selective effects of cannabidiol on tumour cells and support its potential as a targeted bioactive agent. To fully understand its efficacy in the context of various tumour types, more robust research into its mechanisms and safety is needed.