Dichloromethane fraction from Ficus hispida L.f. fruit extract suppresses lung cancer through cell cycle arrest and TNF-induced apoptosis.

Abstract

Ficus hispida L.f., a traditional medicinal plant widely distributed in South and Southeast Asia, has long been used in ethnomedicine to treat respiratory disorders, inflammation and tumor-related conditions. Although previous studies have suggested that F. hispida possesses cytotoxic and anti-inflammatory activities, the in vivo antitumor efficacy and underlying mechanisms of its fruit-derived dichloromethane extract remain unclear. This study aimed to investigate the anti-lung cancer activity of the dichloromethane extract of F. hispida fruits (FHF-DE) using integrated phytochemical, cellular, transcriptomic and in vivo approaches. FHF-DE inhibited the proliferation of multiple human lung cancer cell lines (including H1299, A549, H1975, H460, and PC9 cells) as well as murine Lewis lung carcinoma (LLC) line. Flow cytometry indicated G0/G1 arrest in LLC cells and S-phase arrest in H1975 cells. FHF-DE also promoted apoptotic cell death, as indicated by increased Bax expression, decreased Bcl-2 expression, and caspase-3 activation. Transcriptome sequencing and reverse transcription-quantitative (RT-q) PCR analyses indicated enrichment of the TNF signaling pathway, with increased TNF-α and related gene expression (e.g., IRF1, BIRC3). In an LLC allograft mouse model, daily oral administration of FHF-DE (200-400 mg/kg) significantly suppressed tumor growth, without evident hepatotoxicity or nephrotoxicity in H&E staining. This in vivo finding demonstrates the antitumor efficacy of FHF-DE, although, molecular validation of the proposed mechanism in tumor tissues was not performed. Collectively, our in vitro data demonstrate that FHF-DE induces apoptosis and cell cycle arrest in lung cancer cells, with transcriptomic and pharmacological data suggesting a functional association with TNF-related signaling pathways. However, definitive mechanistic proof of direct TNFR1 engagement or extrinsic apoptotic pathway activation, particularly in vivo, requires further investigation. The present study provides preclinical evidence supporting further pharmacological and toxicological evaluation of F. hispida fruit-derived extracts as natural-product-based candidates for lung cancer intervention.