Abstract
The effects of NIN1/RPN12 binding protein 1 homolog (NOB1) on the pathogenesis of osteosarcoma and its expression on the chemosensitivity to cisplatin were investigated. Seventy-four patients with osteosarcoma who received surgical resection in The Affiliated Hospital of Southwest Medical University (Sichuan, China) from September 2013 to September 2016 were enrolled in this study. The expression of NOB1 in cancer and cancer-adjacent tissues of patients was detected by reverse transcription-polymerase chain reaction, and the relationship between NOB1 expression and the pathogenesis of osteosarcoma was analyzed. The expression of NOB1 in osteosarcoma MG-63 cells was interfered with using small interfering ribonucleic acid (siRNA). Western blotting was used to detect the transfection efficiency and changes in apoptosis indicators. Cell Counting Kit-8 (CCK-8) assay was used to examine changes in the sensitivity of cells to cisplatin. The effect of NOB1 knockout on cell apoptosis was examined by flow cytometry. In patients with osteosarcoma, the level of NOB1 mRNA in cancer tissues was significantly higher than that in cancer-adjacent tissues (p<0.05), and the expression of NOB1 was correlated with Ennecking staging and tumor size (p<0.05). The expression level of the apoptotic indicator caspase-3 was activated after siRNA interfered with NOB1 expression, thus reducing the expression level of anti-apoptotic indicator B-cell lymphoma 2. CCK-8 results showed that the downregulation of NOB1 increased the sensitivity of MG-63 cells to cisplatin (p<0.05). In addition, flow cytometry showed that the downregulation of NOB1 significantly promoted the apoptosis of MG-63 cells. NOB1 is significantly upregulated in patients with osteosarcoma, thus reducing the curative effect of cisplatin chemotherapy, which indicates that the prognosis is poor.