Qianran Hong,1 Weiye Lin,1 Yici Yan,1 Shuangyu Chen,1 Jiayang Li,1 Jieru Yu,2 Ying Zhu,3 Shengliang Qiu1 

1The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, Zhejiang, 310006, People’s Republic of China; 2School of Basic Medical Sciences, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, People’s Republic of China; 3Department of Medical Oncology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, Zhejiang, People’s Republic of China

Correspondence: Ying Zhu, Department of Medical Oncology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, People’s Republic of China, Email ying.zhu@zcmu.edu.cn Shengliang Qiu, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, Zhejiang, 310006, People’s Republic of China, Email shengliang.qiu@zcmu.edu.cn

Purpose: To explore the mechanism of Huashi Jiedu Decoction (HJD) synergizing with 5-fluorouracil (5-Fu) in gastric cancer (GC) therapy.
Methods: MicroRNAs (miRNAs) and genes involved in HJD-mediated GC treatment were identified using ultra-high-performance liquid chromatography coupled with quadrupole-Orbitrap mass spectrometry, network pharmacology, Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and molecular docking. The effects of HJD on 5-Fu sensitivity in BGC-823 cells were evaluated with 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and Western blotting. Synergistic effects in vector-transfected and miRNA-21-3p knockdown cells were assessed by colony formation, wound healing, transwell assays, and flow cytometry (FCM). An in vivo study evaluated the impact of HJD on 5-Fu sensitivity, measuring miRNA-21-3p, tumor protein p53 (p53), N-cadherin, vimentin, and E-cadherin in tumors, along with tumor volume and weight.
Results: miRNA-21-3p and p53 were key targets in HJD’s therapeutic effect on GC. RT-qPCR showed that HJD combined with 5-Fu reduced miRNA-21-3p and upregulated p53 in vector cells and increased p53 mRNA (p < 0.01) and protein (p < 0.05) compared to 5-Fu alone. These effects were abolished in miRNA-21-3p knockdown cells. The combination reduced colony formation by 48.92% (p < 0.01), suppressed transwell migration by 28.5% (p < 0.01), and inhibited wound healing by 81.9% compared to 5-Fu monotherapy (p < 0.001), with no effects in knockdown cells. FCM showed a 15.1% increase in G0/G1 phase arrest (p < 0.05). In vivo, the combination significantly reduced tumor volume (p < 0.05) and weight by 18.7%, with concomitant miRNA-21-3p downregulation (p < 0.0001), EMT marker suppression (N-cadherin, vimentin), and tumor suppressor activation (p53, E-cadherin) versus 5-Fu alone.
Conclusion: HJD enhances 5-Fu’s effects on GC by regulating the miRNA-21-3p/p53 pathway and modulating cadherin expression, supporting its potential as an adjunctive treatment in GC.

Keywords: huashi jiedu decoction, 5-fluorouracil, gastric cancer, miRNAs, p53