In vitro study of 5-FU combined with rhCYGB in treating hypoxia-induced chemotherapy resistance of hepatocellular carcinoma

WANG Yi; HE Shuo; YANG Siyun; ZHANG Jun

doi:10.3969/j.issn.1006-5725.2024.22.005

Abstract：Objective This study explores the efficacy and underlying mechanisms of combining rhCYGB with 5-FU to target hypoxia-induced treatment resistance in liver cancer.The aim is to develop a novel combinato-rial therapy strategy for improving outcomes in patients with refractory liver cancer.Methods The half-maximal inhibitory concentration(IC50)of drugs on liver cancer cells under normoxia and hypoxia was determined,and dose-response curves were generated to assess sensitivity to 5-FU.The combined effects of rhCYGB and 5-FU were analyzed withCompuSyn and SynergyFinder 3.0.Tumor stem cell sphere formation assays and flow cytometry for CD133-positive cells were conducted to evaluate the impact on cancer stemness.Wound healing assays assessed the effects on migration.Results The IC50 values under hypoxia exhibited a significant fold change compared to normoxia(P<0.05),specifically a 15.27-fold,4.25-fold,and 2.34-fold increase for Hep3B,Huh7,and HepG2 cells respectively.Assessment of drug combination effects demonstrated a synergistic interaction between 5-FU and rhCYGB.Compared to the 5-FU monotherapy group,the combination of 5-FU and rhCYGB exerted an inhibitory effect on the formation of liver cancer stem cell spheres(P<0.05)and significantly downregulated the proportion of CD133-positive subpopulations in Hep3B cells(P<0.05).Wound healing assay results revealed a synergistic inhibitory effect on the migration of Hep3B cells after 48 hours of treatment with rhCYGB combined with 5-FU undernormoxia(P<0.05).Conclusions The combination of rhCYGB and 5-FU demonstrates syner-gistic effects in liver cancer.The underlying mechanism may involve the modulation of stemness and cell migration capacity.