galangin and Esophageal-Neoplasms

BACKGROUND Galangin is believed to exert antioxidant effects by inhibition of the NLR family pyrin domain containing 3 (NLRP3) inflammasome, which has been linked to chemotherapy sensitivity in cancers. In this study, we explored the synergistic effect of galangin in combination with the chemotherapy agent 5-fluorouracil (5-FU) in esophageal cancer cells and xenografts. MATERIAL AND METHODS The esophageal squamous epithelium cell line Het-1A and 2 human esophageal cancer cell lines (Eca109, OE19) were used to investigate the effect of galangin with or without 5-FU in vitro through proliferation and invasion analyses, while apoptosis was analyzed in cancer cells. Furthermore, a subcutaneous xenograft tumor model in mice was used to study cancer development in vivo. RESULTS Compared with 5-FU monotherapy, combined galangin and 5-FU treatment reduced human esophageal cancer cell growth activities and invasion abilities. The results suggested that galangin had a chemotherapy-sensitized synergistic antitumor effect induced by 5-FU. The susceptibility of cancer cells to apoptosis, which is linked with chemotherapy sensitivity, was induced by 5-FU and further enhanced by galangin. NLRP3 was identified as being significantly activated by 5-FU, but galangin treatment reversed the effect and inhibited NLRP3 expression, which was accompanied by downregulated interleukin-1b levels. Further investigation showed that the induced apoptotic cascade can be mostly reversed by incubation with an NLRP3 activator, irrespective of AKT signaling. Using xenograft mouse models, we found that galangin exposure further restrained cancer development after 5-FU treatment and increased sensitivity to chemotherapy by suppressing the NLRP3 inflammasome pathway. CONCLUSIONS Our results indicated that galangin played a synergistic anticancer role through NLRP3 inflammasome inhibition when paired with FU-5.

Topics: Animals; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Blotting, Western; Cell Line, Tumor; Down-Regulation; Drug Synergism; Esophageal Neoplasms; Flavonoids; Fluorouracil; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; NLR Family, Pyrin Domain-Containing 3 Protein

Galangin is an active pharmacological ingredient from propolis and Alpinia officinarum Hance, and has been reported to have anti-cancer and antioxidative properties. Berberine, a major component of Berberis vulgaris extract, exhibits potent anti-cancer activities through distinct molecular mechanisms. However, the anticancer effect of galangin in combination with berberine is still unknown. In the present study, we demonstrated that the combination of galangin with berberine synergistically resulted in cell growth inhibition, apoptosis and cell cycle arrest at G2/M phase with the increased intracellular reactive oxygen species (ROS) levels in oesophageal carcinoma cells. Pretreatment with ROS scavenger promoted the apoptosis dramatically induced by co-treatment with galangin and berberine. Treatment with galangin and berberine alone caused the decreased expressions of Wnt3a and β-catenin. Interestingly, combination of galangin with berberine could further suppress Wnt3a and β-catenin expression and induce apoptosis in cancer cells. Additionally, in nude mice with xenograft tumors, the combinational treatment of galangin and berberine significantly inhibited the tumor growth without obvious toxicity. Overall, galangin in combination with berberine presented outstanding synergistic anticancer role in vitro and in vivo, indicating that the beneficial combination of galangin and berberine might provide a promising treatment for patients with oesophageal carcinoma.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Berberine; beta Catenin; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Drug Synergism; Esophageal Neoplasms; Esophageal Squamous Cell Carcinoma; Flavonoids; G2 Phase Cell Cycle Checkpoints; Humans; Male; Mice, Inbred BALB C; Mice, Nude; Oxidative Stress; Reactive Oxygen Species; RNA Interference; Time Factors; Transfection; Tumor Burden; Wnt Signaling Pathway; Wnt3A Protein; Xenograft Model Antitumor Assays