# Screening of Theaflavins That Inhibit Proliferation of Nasopharyngeal Carcinoma Cells Through Metabolomics Approaches

## TL;DR

This study shows that theaflavin-3,3'-digallate (TF3) can inhibit the growth and spread of nasopharyngeal carcinoma cells and induce apoptosis, with changes in key metabolic pathways.

## Contribution

The study identifies TF3 as a potential antitumor agent by revealing its dose-dependent effects on NPC cells and associated metabolic disruptions.

## Key findings

- TF3 significantly inhibits proliferation, migration, and invasion of nasopharyngeal carcinoma cells in a concentration-dependent manner.
- Metabolomics analysis revealed 584 altered metabolites, primarily affecting ABC transporter and amino acid biosynthesis pathways.
- Hoechst staining confirmed TF3-induced apoptosis in cancer cell lines.

## Abstract

To study the inhibitory mechanism of theaflavins on nasopharyngeal carcinoma cells to define a solid Chinese herbal antitumor remedy through metabolomics approaches. Various concentrations of theaflavin‐3,3′‐digallate (TF3) were examined for their effects on proliferation, migration, invasion, and apoptosis of nasopharyngeal carcinoma (NPC) cells by CCK‐8, colony‐forming assay, wound healing assay, trans‐well migration assay, and Hoechst staining assay. Moreover, metabolomics analysis along with UHPLC‐Q‐TOF mass spectrometry and UHPLC‐Q‐Exactive Orbitrap mass spectroscopic analyses were also performed. (1) The CCK‐8 assay results highlighted the activity of CNE‐2 cells exposed to TF3 significantly declined in a concentration‐dependent way. (2) The colony formation assay elucidated TF3 inhibitory effects on the colony formation and proliferation of CNE‐2 cells and C666‐1 cells. The higher the concentration of TF3, the more obvious inhibition in cell proliferation was seen. (3) The scratch test results also confirmed the migration ability of CNE‐2 and C666‐1 cells following the treatment of TF3. By increasing the concentration of TF3, more significant inhibition in the migration and invasion of cancer cells has been observed. (4) Hoechst staining further confirmed that TF3 could induce apoptosis in both of these cancer cell lines in a dose‐dependent way. Metabolomics studies generated about 584 metabolic products of significant alterations in tea polyphenol‐treated NPC cells. Multivariate analyses (PCA, PLS‐DA, OPLS‐DA) help establish precise group separation and model reliability, while differential metabolites were mainly enriched in ABC transporter and amino acid biosynthesis pathways. These findings suggest that tea polyphenols modulate key metabolic networks associated with cancer cell proliferation. TF3 has significantly declined proliferation, migration, and NPC cell invasion.

This study investigated the effects of theaflavin‐3,3′‐digallate (TF3) markedly suppresses the proliferation, migration, invasion of nasopharyngeal carcinoma cells while promoting apoptosis in a dose‐dependent manner. Metabolomic profiling identified 584 altered metabolites, revealing key disruptions in ABC transporter activity and amino acid biosynthesis. TF3 potentially inhibited NPCs growth through targeting metabolic disruption.