Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, USA.
Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, USA.
Exp Cell Res. 2021 Jun 1;403(1):112567. doi: 10.1016/j.yexcr.2021.112567. Epub 2021 Apr 1.
We chose to evaluate Hypoxanthine Guanine Phosphoribosyltransferase (HPRT) as a possible biomarker for prostate cancer due to its involvement in nucleotide synthesis and cell cycle progression. We utilized two prostate cancer cell lines (PC3 and DU145) along with patient tissue and knockdowns to evaluate overall HPRT expression. The surface localization of HPRT was determined utilizing flow cytometry, confocal microscopy, and scanning electron microscopy followed by ADCC to evaluate targeting potential. We found significant upregulation of HPRT within malignant samples with approximately 47% of patients had elevated levels of HPRT compared to normal controls. We also observed a significant association between HPRT and the plasma membrane of DU145 cells (p = 0.0004), but found no presence on PC3 cells (p = 0.14). This was confirmed with scanning electron microscopy and confocal microscopy. ADCC experiments were performed to determine whether HPRT could be used as a target antigen for selective cell-mediated killing. We found that DU145 cells treated with HPRT antibodies had a significantly higher incidence of cell death than both isotype treated samples and PC3 cells treated with the same concentrations of HPRT antibody. Finally, we determined that p53 had a significant impact on HPRT expression both internally and on the surface of cancer cells. These results suggest HPRT as a possible biomarker target for the treatment of patients with prostate cancer.
我们选择评估次黄嘌呤鸟嘌呤磷酸核糖转移酶 (HPRT) 作为前列腺癌的潜在生物标志物，因为它参与核苷酸合成和细胞周期进程。我们使用了两种前列腺癌细胞系 (PC3 和 DU145) 以及患者组织和敲低来评估总体 HPRT 表达。利用流式细胞术、共聚焦显微镜和扫描电子显微镜检测 HPRT 的表面定位，然后进行 ADCC 以评估靶向潜力。我们发现恶性样本中 HPRT 的表达显著上调，约 47%的患者 HPRT 水平高于正常对照。我们还观察到 HPRT 与 DU145 细胞的质膜之间存在显著相关性（p = 0.0004），但在 PC3 细胞中未发现（p = 0.14）。这通过扫描电子显微镜和共聚焦显微镜得到了证实。进行 ADCC 实验以确定 HPRT 是否可用作选择性细胞介导杀伤的靶抗原。我们发现，用 HPRT 抗体处理的 DU145 细胞的细胞死亡发生率明显高于用同种型处理的样品和用相同浓度 HPRT 抗体处理的 PC3 细胞。最后，我们确定 p53 对内源性和癌细胞表面的 HPRT 表达都有显著影响。这些结果表明 HPRT 可作为治疗前列腺癌患者的潜在生物标志物靶标。
