Objective: To observe the effect of protein kinase D1 (PKD1) on the growth and metabolism of oral squamous cell carcinoma HSC-4 cells and related molecular mechanisms in the tumor microenvironment.
Methods: HSC-4 cell lines were transfected with shRNA plasmids. Three groups (Wild, control-shRNA, and PKD1-shRNA) were cultured under acidic or hypoxic environment for a certain time. Western blot was used to detect the expression of autophagy-related and glycolytic-related proteins. The proliferation changes were detected by CCK-8 kits.
Results: The PKD1-knockdown HSC-4 cell line was established. PKD1 silencing increased autophagy activity. Under hypoxic and acidic conditions, the PKD1-knockdown HSC-4 cells showed lower proliferation than the parental cells. PKD1-knockdown also decreased the expression of hypoxia induciblefactor 1α (HIF-1α) and pyruvate kinase M2 (PKM2).
Conclusions: Under hypoxic and acidic conditions, PKD1 gene silencing can increase apoptotic autophagy activity. Downregulated PKD1 gene expression can reduce the glycolysis of oral squamous cell carcinoma cells and inhibit tumor cell proliferation. This study revealed the important role of PKD1 in the metabolism and growth of oral squamous cell carcinoma, making it a possible target for the treatment of oral squamous cell carcinoma.
目的 探讨在酸性缺氧微环境中，蛋白激酶D1（PKD1）对口腔鳞癌HSC-4细胞生长、代谢的调控作用和相关分子机制。方法 口腔鳞癌HSC-4细胞稳定转染PKD1，将未转染组、对照组和转染组细胞分别置于酸性或缺氧环境下进行培养，Western blot检测细胞中PKD1敲除率及细胞自噬相关蛋白和糖酵解相关蛋白表达情况，CCK8试剂盒检测细胞增殖。结果 实验成功建立了PKD1基因沉默的稳定细胞株；酸性环境下，PKD1沉默后细胞自噬活性升高；缺氧环境下，相对于对照组，PKD1基因沉默后细胞缺氧诱导因子1α（HIF-1α）和糖酵解中丙酮酸激酶（PKM2）的表达均显著降低；酸性和缺氧环境下，相对于对照组，PKD1基因沉默后细胞的生长速度显著降低。结论 在酸性和缺氧环境下，PKD1基因沉默可促使口腔鳞癌细胞凋亡性自噬活性升高，且下调PKD1基因表达可抑制口腔鳞癌细胞糖酵解，进而抑制肿瘤细胞增殖。揭示PKD1在口腔鳞癌代谢和生长中的作用，使其成为口腔鳞癌治疗的可能靶点。.
Keywords: cell proliferation; glycolysis metabolism; oral squamous cell carcinoma; protein kinase D1; tumor microenvironment.