Expression of chemokines in gastrointestinal cancer

背景资料。最近的研究表明，一些癌前组织、恶性肿瘤以及培养的癌细胞系都具有分泌趋化因子的能力。巨噬细胞炎性蛋白-1β(MIP-β)属于C-C趋化因子家族，参与多种炎症过程。然而，MIP-β对肿瘤生长的影响尚不清楚。应用抗MIP-1β的特异性单抗，采用免疫组织化学方法检测手术切除的胃癌组织中MIP-1β的表达，并比较不同组织学类型的胃癌组织中MIP-1的表达情况。MIP1β在34.6%的分化型癌中呈弱阳性表达，但其在各细胞的表达强度均低于正常上皮。未分化癌在实质型和弥漫型中呈不同的染色模式。MIP-β在所有实体型生长的未分化癌中完全缺失。相比之下，68%的非实性低分化癌和83%的印戒细胞癌组织中MIP-1β呈强阳性表达。尤其是在浸润性病变前部的癌细胞中，MIP1β呈强阳性表达。在任何病理类型中，MIP-1β的表达水平与癌组织中单个核细胞的浸润程度均无明显相关性。我们的结果提示，胃上皮细胞中MIP-1β的产生可能与胃癌的发生或发展有关，尽管它似乎在肿瘤组织中免疫细胞的募集中并不起主要作用。尤其是MIP1β可能参与了未分化表型胃癌细胞的侵袭过程。

Background. Recently, it has been shown that some precancerous tissues and malignant tumors as well as cultured cancer cell lines are capable of secreting chemokines. Macrophage inflammatory protein-1 β(MIP-β) belongs to the C-C chemokine family that is implicated in a wide range of inflammatory processes. However, how the MIP-β affect tumor growth is unknown.Method. With the specific mAb to MIP-1β, we examined the expression of MIP-1β in surgically resected gastric carcinomas using immunohistochemistry, and compared the expression pattern in various carcinomas with different histology.Result. Weak staining of MIP-1β was detected in 34.6% of differentiated carcinomas, but their staining intensity in each cell was less prominent than in normal epithelium. Undifferentiated carcinomas showed contrasted staining pattern between solid type and diffuse type. MIP-β was completely absent in all the undifferentiated carcinoma with solid type growth pattern. In contrast, MIP-1β was strongly expressed in 68% of non-solid type of poorly differentiated carcinoma and 83% of signet-ring cell carcinoma samples. In particular, MIP-1β was strongly stained in carcinoma cells at the front of invasive lesions. In any pathological types, the expression level of MIP-1β did not have a significant correlation with the degree of mononuclear cell infiltration in cancer tissue.Conclusion. Our results suggest the possibility that MIP-1β production in gastric epithelium may be related to the development or progression of gastric cancer, although it does not seem to play a major role in the recruitment of immune cells in cancer tissue. Especially, MIP-1β may contribute to the invasion step of gastric carcinoma cells with undifferentiated phenotype.