Network Pharmacology and Preliminary in Vitro Evaluation of Piper longum (Indian Long Pepper) in Breast Cancer

Abstract

Background and Objectives: Piper longum (Indian Long Pepper) contains phytochemicals reported to have anticancer activity, but their targets and effects in breast-cancer models remain uncertain. This exploratory study combined network pharmacology, analysis of public breast cancer data, molecular docking, MCF-7 viability, DNA cell cycle, and apoptosis assays.

Methods: Nineteen compounds from P. longum fruit were identified using the literature and phytochemical databases. Target prediction tools and cancer gene databases were used to identify interactions with breast cancer genes. Protein–protein interaction, gene ontology, and pathway analyses highlighted key targets. Molecular docking was used to evaluate binding affinities, and in vitro assays assessed cytotoxicity in MCF-7 breast cancer cells.

Results: This study revealed 600 common gene targets between P. longum compounds and breast cancer. Compound-target-disease network analysis prioritized Norcepharadione B, Aristolodione, Pellitorine, Aristolactam AII, and N-isobutyl decadienamide as candidate compounds. Significant breast cancer genes (TP53, CTNNB1, STAT3, SMAD3, EGFR, and HSP90AA1) were central to these interactions. Notably, HSP90AA1 showed the most favorable predicted docking scores with Norcepharadione B and Aristolactam AII. Additionally, the aqueous extract of P. longum significantly inhibited the MCF-7 MTT signal, with an IC50 of 3.75 μg/mL.

Conclusion and Implications for Translation: In this study, Piper longum phytochemicals were linked to key cancer genes. Molecular docking of the top five compounds with six genes showed that Norcepharadione B had the strongest affinity for HSP90AA1, indicating its potential to modulate HSP90AA1-mediated pathways, including ER and HER2 signaling. These interactions suggest therapeutic relevance. Furthermore, aqueous P. longum extract inhibited MCF-7 cellular metabolism at the IC₅₀ dose, possibly through cell-cycle arrest or apoptosis, which is currently under further investigation in our laboratory. These findings support further testing of defined P. longum compounds in breast-cancer models, but they do not yet establish therapeutic activity or mechanism.