Novel Molecular Pharmacological Strategy in Clinical Therapeutic Research

差异显示是一种依靠聚合酶链反应来鉴定相关组织样品之间信使RNA差异的技术。我们采用了一种改进的差异显示技术，称为荧光差异显示（FDD），以确定在正常和恶性乳腺组织中差异表达的基因。从FDD指纹图谱中，我们确定了总共5，837条谱带中约3%（185条谱带）的强度变化。这185个条带中的每一个都代表了差异表达的基因，我们将注意力集中在钙结合EF-手蛋白超家族的成员caltractin基因的表达上。北方杂交结果显示，乳腺癌组织中caltractin mRNA的表达水平均高于相应的正常组织（5/5），而且caltractin基因在其他恶性肿瘤如肝细胞癌（HCC）、胃癌和平滑肌肉瘤中也有高水平表达。原位杂交结果显示，肿瘤浸润淋巴细胞（TIL）中的caltractin mRNA表达较强，而恶性肿瘤细胞中的caltractin mRNA表达较弱。我们的数据表明，caltractin基因可能与TIL的功能和潜在的治疗靶点。

Differential display is a technique which relies on the polymerase chain reaction to identify messenger RNA differences between related tissue samples. We have employed an improved differential display technique, called fluorescent differential display (FDD), to identify the genes that are differentially expressed in normal and malignant mammary tissues. From FDD fingerprints, we identified changes in intensity of approximately 3% (185 bands) of a total of 5, 837 bands. Each of these 185 bands represented a differentially expressed gene, and we focused our attention on the expression of the gene for caltractin, a member of the calcium-binding EF-hand protein superfamily. Northern blot analysis revealed that the level of mRNA for caltractin was higher in breast carcinoma than in corresponding normal tissue in all cases tested (5/5).Moreover, high-level expression of the gene for caltractin was also recognized in other malignant tumors, such as hepatocellular carcinoma (HCC), gastric cancer and leiomyosarcoma. The results of in situ hybridization showed strong stainings for caltractin mRNA in tumor-infiltrating lymphocytes (TIL), but not in malignant tumor cells. Our data suggests that the caltractin gene might be associated with the function of TIL and potential therapeutic target.