Abstract：
Cancer metabolism has emerged as a potential target for innovative therapeutic approaches in the treatment of cancer. Cancer metabolism has received much attention, particularly in relation to glucose metabolism. It has been observed that human malignancies have high levels of glucose-6-phosphate dehydrogenase (G6PD) activity which is an important enzyme of glucose metabolism. This overactivity is associated with the cell death and angiogenesis, highlighting its potential as a viable target for cancer treatment. This study was conducted to examine the methanolic extracts from the seeds, bark and leaves of litchi (Litchi chinensis Sonn.) in order to discover effective compounds targeting G6PD and potentially active entities against liver cancer. Plant extract screening for the target protein was carried out through enzymatic activity assay. The recombinant plasmid pET-24a-HmG6PD was expressed in E. coli (BL21-DE3) strain, then purified and assessed using metal affinity chromatography with Ni-NTA columns and SDS-PAGE. The cytotoxicity of plant extracts against liver cancer HepG2 cells was assessed using the MTT assay. All three extracts demonstrated significant inhibitory effects (>80% inhibition) against G6PD. They were then subjected to testing at various concentrations, and their IC50 values were subsequently determined. The extracts of litchi (leaf, IC50: 1.199 μg/mL; bark, IC50: 2.350 μg/mL; seeds, IC50: 1.238 μg/mL) displayed significant inhibition of G6PD activity at lower concentrations. Subsequently, the leaf extract of litchi was further assessed for its impact on HepG2 cell lines in a dose-dependent manner and exhibited strong potential as an inhibitor of cancer cell progression. Moreover, the results of acute toxicity study in mice revealed nontoxic effects of litchi leaf extract on hepatocytes. The results imply that Litchi chinensis leaf extract could be considered as a promising candidate for safer drug development in the treatment of liver cancer.
摘要：
癌症代谢已成为癌症治疗中创新治疗方法的潜在靶标。癌症的代谢受到了广泛的关注,特别是与葡萄糖代谢有关。已经观察到人类恶性肿瘤具有高水平的葡萄糖-6-磷酸脱氢酶(G6PD)活性,其是葡萄糖代谢的重要酶。这种过度活动与细胞死亡和血管生成有关，强调其作为癌症治疗的可行靶点的潜力。这项研究是为了检查从种子中提取的甲醇，荔枝的树皮和叶子（荔枝。)，以发现靶向G6PD的有效化合物和针对肝癌的潜在活性实体。通过酶活性测定进行植物提取物对靶蛋白的筛选。重组质粒pET-24a-HmG6PD在大肠杆菌(BL21-DE3)中表达,然后使用Ni-NTA柱的金属亲和层析和SDS-PAGE进行纯化和评估。使用MTT测定法评估植物提取物对肝癌HepG2细胞的细胞毒性。所有三种提取物均表现出对G6PD的显著抑制作用(>80%抑制)。然后对它们进行各种浓度的测试，随后测定其IC50值。荔枝的提取物（叶，IC50:1.199μg/ml;树皮,IC50:2.350μg/ml;种子,IC50：1.238μg/ml）在较低浓度下显示出对G6PD活性的显着抑制。随后，以剂量依赖性方式进一步评估了荔枝叶提取物对HepG2细胞系的影响,并显示出作为癌细胞进展抑制剂的强大潜力.此外，小鼠急性毒性研究结果揭示了荔枝叶提取物对肝细胞的无毒作用。结果表明，荔枝叶提取物可被认为是治疗肝癌的更安全药物开发的有希望的候选药物。
