Huang Yaling, Cao Guochun, Wang Hui, Wang Qingling, Hou Yayi
Immunology and Reproduction Biology Lab, Medical School and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, China.
Cell Mol Immunol. 2007 Apr;4(2):135-40.
Midkine (MK), a heparin-binding growth factor, can regulate cell growth, survival and differentiation. MK is expressed at high levels in a variety of human carcinomas. Recently, the urine and serum MK concentration was analyzed in gastric cancer patient. However, the association of the cytokine mRNA expression with the categorical clinicopathological variables of the tumors and the location of its protein expression in the tumor tissues are still elusive. MK mRNA expression from the surgically resected specimens of healthy gastric tissues (9 cases), gastric cancer tissues and the matched non-cancerous tissues adjacent to the cancer (37 cases) were assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time PCR. Immunohistochemical analysis was performed to locate MK in gastric cancer. The expression of MK mRNA in gastric cancer was much higher in tumor tissues than that in the non-cancerous tissues and control tissue samples. And its expression was significantly associated with the pTNM stage and distant metastasis, but not with the differentiation grade, tumor size and nodal involvement. MK protein was ubiquitous in the tumor, especially in the adenoid part of tumors. In addition, it was found in the cytoplasm of tumor cells and highly concentrated in nucleus and nucleolus. The expression level and location of MK in gastric tumor tissues of Chinese patients may be related to the tumor genesis and progression. Further study is necessary on the mechanism of MK in gastric tumorigenesis and tumor growth.
中期因子（MK）是一种肝素结合生长因子，可调节细胞生长、存活和分化。MK在多种人类癌症中高表达。最近，对胃癌患者的尿液和血清MK浓度进行了分析。然而，细胞因子mRNA表达与肿瘤的分类临床病理变量及其在肿瘤组织中的蛋白表达位置之间的关联仍不明确。通过逆转录聚合酶链反应（RT-PCR）和实时PCR评估了9例健康胃组织、胃癌组织以及与癌症相邻的配对非癌组织（37例）手术切除标本中的MK mRNA表达。采用免疫组织化学分析在胃癌中定位MK。胃癌中MK mRNA在肿瘤组织中的表达远高于非癌组织和对照组织样本。其表达与pTNM分期和远处转移显著相关，但与分化程度、肿瘤大小和淋巴结受累无关。MK蛋白在肿瘤中普遍存在，尤其是在肿瘤的腺样部分。此外，在肿瘤细胞的细胞质中发现它，并高度集中在细胞核和核仁中。中国患者胃肿瘤组织中MK的表达水平和位置可能与肿瘤的发生和进展有关。有必要进一步研究MK在胃肿瘤发生和肿瘤生长中的机制。
