Ilex kudingcha’s phenolic-rich fraction inhibits murine squamous cell carcinoma (SCC7) through restoring adaptive immunity and Th1-polarized immune balance in vitro and in vivo

Abstract

The Ilex kudingcha methanol extract ethanol supernatent (ESIKME) was analyzed for its phenolic compounds using high-performance liquid chromatography. Murine squamous cell carcinoma (SCC)-7 was treated in vitro and in vivo. ESIKME was found abundant in 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid and modulated the immune response toward Th1-polarized immune balance through changing the splenocytes’ Th1/Th2 cytokine secretion profile in vitro. ESIKME had a significant effect against SCC7 cells in vitro. ESIKME administration by daily gavage for 26 days did not cause any apparent toxicity to SCC7-bearing mice. There were relatively lower tumor weights in the medium dose group (KM, 100 mg/kg b.w./day). KM administration slightly restored the B-cell and T-cell immunity through increasing serum non-specific antibody levels and the splenocytes’ proliferative ability in the experimental mice. KM administration tended to increase Th1-polarized immune balance through increasing (IL-2+TNF-⍺)/IL-10 (Th1/Th2) secretion ratios using splenocytes isolated from the experimental mice. Th1/Th2 cytokine secretion ratios by splenocytes were negatively correlated with tumor weights, revealing that ESIKME inhibits SCC7 through restoring adaptive immunity and Th1-polarized immune balance. Our results are the first to prove that ESIKME, which is a phenolic-rich fraction, inhibits SCC7 through partly restoring adaptive immunity and Th1-polarized immune balance in the tumor-bearing mice.