Targeting the hsa-miR-155-5p-BACH1-MMP-9 Signaling Hub in Lung Cancer: A Novel Anticancer Mechanism of Thymoquinone.

OBJECTIVE

Lung cancer (LC) remains a leading cause of cancer mortality worldwide. Thymoquinone (TQ), a bioactive compound derived from Nigella sativa, possesses anti-inflammatory and antioxidant properties, but its precise mechanisms concerning miRNA regulation in LC are poorly defined. This study investigates the anti-cancer potential of TQ through modulation of microRNA signaling in LC.

METHODS

We employed an integrated approach combining bioinformatic predictions with rigorous experimental validation in A549 lung adenocarcinoma cells and SHP-77 human small-cell lung carcinoma (SCLC) cells. Bioinformatic analyses predicted miRNA targets, and experimental techniques included dual-luciferase reporter assays, miRNA inhibition, TaqMan RT-qPCR, cell-based ELISA, and Western blotting to dissect the molecular pathway.

RESULTS

We identified the transcription factor BACH1 as a direct and novel target of hsa-miR-155-5p. TQ potently suppressed interferon-γ-induced expression of both hsa-miR-155-5p and its target, BACH1. This TQ-mediated suppression led to subsequent downregulation of the key metastasis-promoter Matrix Metalloproteinase-9 (MMP-9). Genetic inhibition of miR-155-5p or direct BACH1 inhibition phenocopied the effects of TQ, confirming the functional significance of this axis. Thus, we define a novel oncogenic signaling cascade-the hsa-miR-155-5p/BACH1/MMP-9 axis that is effectively disrupted by TQ.

CONCLUSIONS

This represents the first evidence that TQ exerts its anti-cancer effects in LC through the modulation of the critical signaling cascade (hsa-miR-155-5p → BACH1 → MMP-9). Our findings establish TQ as a multi-targeted agent capable of simultaneously inhibiting miRNA-mediated oncogenic signaling and protein-level effectors. The dual therapeutic action of TQ represents a novel therapeutic strategy and underscores its potential for synergistic combination therapies.