Acute Modulation of PER2 Mrna Expression in Synchronized MCF-7 Breast Cancer Cells Following Honokiol Treatment: An 8-Hour Pilot Investigation

Abstract

Honokiol has been reported to exert broad antineoplastic activity through multiple signaling pathways, while circadian gene dysregulation, including PER2 downregulation, is increasingly recognized in breast cancer. In this pilot study, PER2 expression was examined to determine whether honokiol acutely modulates its levels in synchronized MCF-7 breast cancer cells after 8 h of treatment. Cells were exposed to 5, 10, or 20 µM honokiol, with medium-only and DMSO vehicle controls included for comparison. PER2 mRNA levels were quantified by qRT-PCR and normalized to ACTB using the comparative Ct method. In this experiment, the DMSO vehicle group showed lower PER2 expression than the medium-only control, highlighting a vehicle-associated suppression under the present conditions. Interestingly, honokiol produced a non-linear, concentration-dependent response: treatment with 10 µM honokiol upregulated PER2 expression (~2.90-fold) compared to the DMSO vehicle, showing the strongest capacity to rescue the circadian clock suppression. In contrast, 5 µM and 20 µM doses showed expression levels closer to the DMSO baseline. These data suggest that acute honokiol exposure modulates PER2 expression in a concentration-sensitive manner, effectively rescuing solvent-induced chrono disruption. However, these findings remain preliminary as they are based on a single 8-hour time point, necessitating future time-course and protein-level validations.

Keywords

• Honokiol
• MCF-7
• Per2
• Circadian rhythm
• Breast cancer

Supporting Institution

Niğde Ömer Halisdemir University

Project Number

FMT 2026/1-HIDEP.

Ethical Statement

Ethics committee approval was not required for this study because of there was no study on animals or humans.

Thanks

This research was funded and supported by Niğde Ömer Halisdemir University, Project Number: FMT 2026/1-HIDEP.

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