Yokoyama Seiya, Kitamoto Sho, Higashi Michiyo, Goto Yuko, Hara Taro, Ikebe Dai, Yamaguchi Taketo, Arisaka Yoshifumi, Niihara Toru, Nishimata Hiroto, Tanaka Sadao, Takaori Kyoichi, Batra Surinder K, Yonezawa Suguru
Department of Human Pathology, Field of Oncology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Kagoshima, Japan.
Division of Endoscopy, Chiba Cancer Center, Chiba, Chiba, Japan.
PLoS One. 2014 Apr 8;9(4):e93760. doi: 10.1371/journal.pone.0093760. eCollection 2014.
Mucins (MUC) play crucial roles in carcinogenesis and tumor invasion in pancreatic ductal adenocarcinoma (PDAC) and intraductal papillary mucinous neoplasms (IPMNs). Our immunohistochemistry (IHC) studies have shown a consensus position on mucin expression profiles in pancreatic neoplasms as follows: MUC1-positive but MUC2-negative expression in PDACs; MUC1-negative but MUC2-positive expression in intestinal-type IPMNs (dangerous type); MUC1-negative and MUC2-negative expression in gastric-type IPMNs (safe type); High MUC4 expression in PDAC patients with a poor outcome; and MUC4-positive expression in intestinal-type IPMNs. We also showed that three mucin genes (MUC1, MUC2 and MUC4) expression in cancer cell line was regulated by DNA methylation. We have developed a novel 'methylation-specific electrophoresis (MSE)' method to analyze the DNA methylation status of mucin genes by high sensitivity and resolution. By using the MSE method, we evaluated pancreatic juice samples from 45 patients with various pancreatic lesions. The results were compared with final diagnosis of the pancreatic lesions including IHC of mucin expression in the paired pancreatic tissues. The results indicated that the DNA methylation status of MUC1, MUC2 and MUC4 in pancreatic juice matched with the mucin expression in tissue. Analyses of the DNA methylation status of MUC1, MUC2 and MUC4 were useful for differential diagnosis of human pancreatic neoplasms, with specificity and sensitivity of 87% and 80% for PDAC; 100% and 88% for intestinal-type IPMN; and 88% and 77% for gastric-type IPMN, respectively. In conclusion, MSE analysis of human pancreatic juice may provide useful information for selection of treatment for pancreatic neoplasms.
粘蛋白（MUC）在胰腺导管腺癌（PDAC）和导管内乳头状黏液性肿瘤（IPMN）的致癌作用和肿瘤侵袭过程中发挥着关键作用。我们的免疫组织化学（IHC）研究已就胰腺肿瘤中粘蛋白表达谱达成如下共识：PDAC中MUC1呈阳性但MUC2呈阴性表达；肠型IPMN（危险型）中MUC1呈阴性但MUC2呈阳性表达；胃型IPMN（安全型）中MUC1和MUC2均呈阴性表达；预后不良的PDAC患者中MUC4高表达；肠型IPMN中MUC4呈阳性表达。我们还表明，癌细胞系中三种粘蛋白基因（MUC1、MUC2和MUC4）的表达受DNA甲基化调控。我们开发了一种新型的“甲基化特异性电泳（MSE）”方法，以高灵敏度和分辨率分析粘蛋白基因的DNA甲基化状态。通过使用MSE方法，我们评估了45例患有各种胰腺病变患者的胰液样本。将结果与胰腺病变最终诊断结果进行比较，包括配对胰腺组织中粘蛋白表达的免疫组织化学检测结果。结果表明，胰液中MUC1、MUC2和MUC4的DNA甲基化状态与组织中的粘蛋白表达情况相符。对MUC1、MUC2和MUC4的DNA甲基化状态进行分析，对人类胰腺肿瘤的鉴别诊断有用，对PDAC的特异性和敏感性分别为87%和80%；对肠型IPMN分别为100%和88%；对胃型IPMN分别为88%和77%。总之，对人类胰液进行MSE分析可能为胰腺肿瘤治疗方案的选择提供有用信息。
