Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
Division of General Surgery, Department of Surgery, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan.
Dis Markers. 2019 Jan 3;2019:4569718. doi: 10.1155/2019/4569718. eCollection 2019.
Osteosarcoma (OS) is the most common and most aggressive primary solid malignant bone tumor in children and young adults and has high rates of recurrence and metastasis. The endoplasmic reticulum (ER) stress pathway is important in regulating the chemo-responsiveness of cancer. However, the role of glucose-regulated protein 94 (GRP94) in regulating the response of OS to chemotherapy has never been explored.
In this study, two OS cell lines, MG63 and 143B cells, were used to evaluate the mechanism by which GRP94 modulates the response of osteosarcoma to chemotherapy. GRP94-knockdown (GRP94-KD) OS cells were generated using short hairpin RNAs, and the response to chemotherapy was assessed using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Cell apoptosis was quantified with propidium iodide (PI) staining and flow cytometry.
Silencing of GRP94 in MG63 and 143B cells did not influence the growth and migration of the cells, but reduced the colony formation. GRP94-KD OS cells were more resistant to paclitaxel, gemcitabine, and epirubicin treatments than cells transfected with the scrambled control, and more cells transfected with the scrambled control underwent apoptosis after paclitaxel, gemcitabine, and epirubicin treatments than GRP94-KD cells.
Therefore, GRP94 silencing may increase the resistance of MG63 and 143B cells to paclitaxel, gemcitabine, and epirubicin treatments by inhibiting the induction of apoptosis. Thus, GRP94 may be a key biomarker for the chemotherapeutic response of OS.
骨肉瘤（OS）是儿童和青少年中最常见和最具侵袭性的原发性实体恶性骨肿瘤，其复发和转移率很高。内质网（ER）应激途径在调节癌症的化疗反应中起着重要作用。然而，葡萄糖调节蛋白 94（GRP94）在调节骨肉瘤对化疗的反应中的作用从未被探索过。
在这项研究中，使用了两种骨肉瘤细胞系，MG63 和 143B 细胞，来评估 GRP94 调节骨肉瘤对化疗反应的机制。使用短发夹 RNA 生成 GRP94 敲低（GRP94-KD）骨肉瘤细胞，并使用 MTT（3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐）测定法评估对化疗的反应。用碘化丙啶（PI）染色和流式细胞术定量细胞凋亡。
沉默 MG63 和 143B 细胞中的 GRP94 并不影响细胞的生长和迁移，但减少了集落形成。与转染 scrambled 对照的细胞相比，GRP94-KD 骨肉瘤细胞对紫杉醇、吉西他滨和表柔比星的治疗更具抵抗力，而在用紫杉醇、吉西他滨和表柔比星处理后，转染 scrambled 对照的细胞比 GRP94-KD 细胞有更多的细胞发生凋亡。
因此，GRP94 沉默可能通过抑制细胞凋亡的诱导，增加 MG63 和 143B 细胞对紫杉醇、吉西他滨和表柔比星治疗的耐药性。因此，GRP94 可能是骨肉瘤化疗反应的关键生物标志物。
