The oxamate effect and mechanism in inhibiting the proliferation of anaplastic thyroid cancer

Abstract

Objective To evaluate the antitumor effect of oxamate as a lactate dehydrogenase (LDH) inhibitor on Anaplastic human thyroid cancer, and to explore the therapeutic effect of inhibiting cancer metabolism on Anaplastic thyroid cancer (ATC). Methods Immunohistochemistry were used to detect the expression of LDHa in 12 cases of human ATC and adjacent tissues. Methyl thiazol tetrazolium (MTT) assay and plate cloning assay was used to detect the effect of Oxamate on the proliferation of ATC cell lines. The effects of Oxamate on the activity of LDH and the formation of lactate were detected by lactate dehydrogenase kit and lactate detection kit. Western blotting was used to detect changes in protein expression related to cell proliferation. Results Immunohistochemical staining showed that the positive rates of LDHa protein in cancer and adjacent tissues were 46.0% and 14.1% respectively, and the difference was statistically significant (P=0.004) LDH inhibitor oxamate was used to treat Hth83 and SW1736 cell lines in 0, 5, 10, 20, 40, 60, 80, 100 mmol/L, MTT assay showed that the 50% growth inhibitory concentration (IC50) of the Hth83 cell group was 64.3, 24.4, and 10.1 mmol/L, while in the SW1736 cell group, the IC50 values were 82.5 and 51.2, 25.3 mmol/L at 24, 48, and 72 h. The clone formation test indicated that two cell lines clone formation ability was also significantly declined, and the degree of decrease was positively correlated with the drug concentration (P=0.012). This inhibition was accompanied by a decrease in the activity of lactate dehydrogenase and the production of lactate. Western blotting analysis showed that the expression of phosphorylated protein kinase B (p-Akt), Cyclin D1, and phosphorylated glycogen synthase kinase 3β (p-GSK-3β) was down-regulated. Conclusion LDHa is highly expressed in human ATC tissues. Oxamate, as an inhibitor of LDH enzyme, can decrease the proliferation potential of Hth83 and SW1736 cell lines. The possible molecular mechanism is that the Akt-Cyclin D1 protein pathway is inhibited. Key words: Oxamate; Lactate dehydrogenase; Thyroid carcinoma; Proliferation