Lactoferrin-induced apoptosis and PLD activation in oral squamous cell carcinoma cell line

乳铁蛋白诱导口腔鳞状细胞癌细胞系凋亡和 PLD 激活

• 批准号: 13672128
• 负责人: SAKAI Takayuku
• 金额: $ 2.05万
• 依托单位: Toho University (2002)Tsurumi University (2001)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13672128/
• 关键词: Lactoferrin; Apoptosis; Oral cancer; Phospholipase D; MAP kinase; Tyrosine kinase; Protein kinase C; Inhibitor; フォスフォリバーゼD; PMA; PKC

In the present study, I examined biological mechanisms of apoptosis induced by pepsin hydrolyzed-lactoferrin (lactoferricin) in oral squamous cell carcinoma cell lines.【RESULTS】The treatment of oral cancer cells with pepsin-digested lactoferrin caused changes as followed.1) Suppressed |3H|thymidine incorporation.2) Induced condensation of chromatin stained by Hoechst 33258.3) Induced the fragmentation of DNA.4) Increased the leak of intracellular LDH.5) Increased ERK protein phosphorylation (=activations).6) Elongated serum-induced ERK, JNK protein phosphorylation.7) Stimulated PLD activation.8) Suppressed mRNA expression of PKC ε and η isozymes【Conclusion】In this study, we found that lactoferricin peptides, produced by acid-pepsin hydrolysis of bovine lactoferrin, induced cell death involving apoptotic nuclear change in human oral squamous cell carcinoma cell lines. At early stage of apoptosis, the treatment of lactoferricin induced activations of ERK, and PLD and prolonged serum-induced activations of ERK and JNK at later stage (24-27 hrs). Moreover, 6hrs treatment of lactoferricin peptides decreased mRNA expression levels of protein kinase Cε and η isozymes. These changes of signaling enzymes may play a role in apoptotic process of oral cancer cells induced by lactoferricin peptides.

在本研究中，我研究了胃蛋白酶水解乳铁蛋白（乳铁蛋白）诱导口腔鳞状细胞癌细胞凋亡的生物学机制。【结果】胃蛋白酶消化乳铁蛋白对口腔癌细胞的影响如下：1)抑制bbb3h |胸苷结合。2)诱导Hoechst 3325染色的染色质凝结8.3)诱导dna断裂4)增加细胞内ldh的泄漏5)增加ERK蛋白磷酸化（=活化）。6)延长血清诱导的ERK、JNK蛋白磷酸化。7)受激PLD激活。【结论】本研究发现酸性胃蛋白酶水解牛乳铁蛋白产生的乳铁蛋白肽可诱导人口腔鳞状细胞癌细胞株细胞死亡，并引起细胞核凋亡改变。在细胞凋亡早期，乳铁蛋白处理诱导ERK、PLD活化，并在后期延长血清诱导的ERK、JNK活化（24-27小时）。此外，乳铁蛋白肽处理6小时可降低蛋白激酶Cε和η同工酶的mRNA表达水平。这些信号酶的变化可能在乳铁蛋白肽诱导口腔癌细胞凋亡过程中发挥作用。