Tigecycline affects RAC1 and OXPHOS and shows antitumor effect in hepatocellular carcinoma

Yu, Haochen (2022): Tigecycline affects RAC1 and OXPHOS and shows antitumor effect in hepatocellular carcinoma. Dissertation, LMU München: Medizinische Fakultät

Abstract

Background: Currently, hepatocellular carcinoma (HCC) has a high morbidity and mortality rate and corresponding treatment options are limited. Liver transplantation is highly limited by organ supply and liver resection is limited by high recurrence rates and there are no adjuvant therapy options to date. As antibiotic research progressed, antitumor effects of antibiotics were discovered. Therefore, we chose Tigecycline, a glycylcycline antibiotic, as the subject of our study to investigate the anti-HCC effects and to explore its mechanism to provide a perioperative antitumor therapy option. Methods: HCC cells and hepatocytes were treated with different concentra-tions of Tigecycline. MTT and CV were used to assay their cell viability and to calculate IC50. Sphere formation assays measured changes in cell stem-ness. To assess changes in cell migration and invasion capabilities, wound healing and transwell assays are used. RAC1 was identified as a possible target for Tigecycline by bioinformatics analysis. The expression of key markers was detected using Western blot and RT-PCR. DCHA was utilized to measure reactive oxygen species generation during Tigecycline therapy. FACS was used to detect alterations in cell cycle following Tigecycline treat-ment and changes in mitochondrial function were detected via seahorse anal-ysis. Results: After Tigecycline treatment of HCC cells the viability was reduced significantly. The sensitivity of HCC cells to Tigecycline was higher than that of immortalized normal hepatocytes THLE-2. Tigecycline inhibited both migration and invasion of HCC cells. HCC or hepatocytes cells showed increased expression of RAC1, decreased ROS production, reduced mitochondrial function and arrested in S-phase of the cell cycle after Tigecycline treatment. The inhibition of HCC cells is enhanced when Tigecycline is used in combination with Everolimus. Conclusion： Our study firstly revealed the inhibitory effect of Tigecycline on HCC. Inhibition of RAC1, cell cycle arrest, reduction of ROS and mitochondrial oxidative phosphorylation may all be involved in the process. Most importantly, we also studied the effects of Tigecycline on normal hepatocytes and found that it caused limited damage to normal hepatocytes. Our findings provide more possibilities for the clinical use of Tigecycline in HCC.

• Dokumententyp: Dissertationen (Dissertation, LMU München)
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften ; 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• Fakultäten: Medizinische Fakultät
• Sprache der Hochschulschrift: Englisch
• Datum der mündlichen Prüfung: 22. Juli 2022
• 1. Bericht­erstatter:in: Bazhin, Alexandr