Methoxyeugenol regulates the p53/p21 pathway and suppresses human endometrial cancer cell proliferation

Plant-derived compounds are a reservoir of natural chemicals and can act as drug precursors or prototypes and pharmacological probes. Methoxyeugenol is a natural compound found in plant extracts, such as nutmeg (Myristica fragrans), and it presents anthelmintic, antimicrobial, anti-inflammatory activities. Recently, interest in the anticancer activity of plant extracts is increasing and the therapeutic activity of methoxyeugenol against cancer has not yet been explored.

The present study aimed to evaluate the cancer-suppressive role and the molecular signaling pathways of methoxyeugenol in human endometrial cancer (Ishikawa) cell line.

Proliferation, viability, and cell toxicity were assessed by direct counting, MTT assay, and LDH enzyme release assay, respectively. Antiproliferative effect were evaluated by nuclear morphological changes along with the cellular mechanisms of apoptosis and senescence by flow cytometry. The underlying molecular and cellular mechanisms were investigated by RT-qPCR, reactive oxygen species (ROS) levels, mitochondrial dysfunction, and proliferative capacity.

Methoxyeugenol treatment significantly inhibited the proliferation and viability of Ishikawa cells. Probably triggered by the higher ROS levels and mitochondrial dysfunction, the gene expression of p53 and p21 increased and the gene expression of CDK4/6 decreased in response to the methoxyeugenol treatment. The rise in nuclear size and acidic vesicular organelles corroborate with the initial senescence-inducing signals in Ishikawa cells treated with methoxyeugenol. The antiproliferative effect was not related to cytotoxicity and proved to effectively reduce the proliferative capacity of endometrial cancer cells even after treatment withdrawal. These results demonstrated that methoxyeugenol has a promising anticancer effect against endometrial cancer by rising ROS levels, triggering mitochondrial instability, and modulating cell signaling pathways leading to an inhibition of cell proliferation.