Division of Neurosurgery, Department of Neurological Surgery, Nihon University School of Medicine, Tokyo 173-8610, Japan.
Division of Anatomical Science, Department of Functional Morphology, Nihon University School of Medicine, Tokyo 173-8610, Japan.
Int J Oncol. 2019 May;54(5):1864-1874. doi: 10.3892/ijo.2019.4743. Epub 2019 Mar 7.
Malignant melanoma is a highly aggressive skin cancer that is highly resistant to chemotherapy. Adjuvant therapy is administered to patients with melanoma that possess no microscopic metastases or have a high risk of developing microscopic metastases. Methylating agents, including dacarbazine (DTIC) and temozolomide (TMZ), pegylated interferon (IFN)‑α2b and interleukin‑2 have been approved for adjuvant immuno‑chemotherapy; however, unsatisfactory results have been reported following the administration of methylating agents. IFN‑β has been considered to be a signaling molecule with an important therapeutic potential in cancer. The aim of the present study was to elucidate whether antitumor effects could be augmented by the combination of TMZ and IFN‑β in malignant melanoma. We evaluated the efficacy of TMZ and IFN‑β by comparing O6‑methylguanine‑DNA transferase (MGMT)‑proficient and ‑deficient cells, as MGMT has been reported to be associated with the resistance to methylating agents. Cell viability was determined by counting living cells with a Coulter counter, and apoptosis was analyzed by dual staining with Annexin V Alexa Fluor® 488 and propidium iodide. The expression of proteins involved in the cell cycle, apoptosis and autophagy was evaluated by western blot analysis. The combined treatment with TMZ and IFN‑β suppressed cell proliferation and induced cell cycle arrest. We also demonstrated that a combination of TMZ and IFN‑β enhanced apoptosis and autophagy more efficiently compared with TMZ treatment alone. These findings suggest that antitumor activity may be potentiated by IFN‑β in combination with TMZ.
恶性黑色素瘤是一种高度侵袭性的皮肤癌，对化疗具有高度耐药性。辅助治疗用于没有显微镜下转移或有发生显微镜下转移高风险的黑色素瘤患者。已批准使用甲基化剂（包括达卡巴嗪[DTIC]和替莫唑胺[TMZ]）、聚乙二醇化干扰素[IFN]-α2b 和白细胞介素-2 进行辅助免疫化疗；然而，使用甲基化剂后的结果并不令人满意。IFN-β 被认为是一种信号分子，在癌症治疗中具有重要的治疗潜力。本研究旨在阐明 TMZ 和 IFN-β 的联合应用是否可以增强恶性黑色素瘤的抗肿瘤作用。我们通过比较 O6-甲基鸟嘌呤-DNA 转移酶（MGMT）阳性和阴性细胞来评估 TMZ 和 IFN-β 的疗效，因为据报道 MGMT 与对甲基化剂的耐药性有关。用库尔特计数器计数活细胞来确定细胞活力，并用 Annexin V Alexa Fluor®488 和碘化丙啶双重染色来分析细胞凋亡。通过 Western blot 分析评估参与细胞周期、细胞凋亡和自噬的蛋白质表达。TMZ 和 IFN-β 的联合治疗抑制细胞增殖并诱导细胞周期停滞。我们还表明，与 TMZ 单独治疗相比，TMZ 和 IFN-β 的联合治疗更有效地增强了细胞凋亡和自噬。这些发现表明 IFN-β 与 TMZ 联合使用可能增强抗肿瘤活性。
