Jiang Wen G, Davies Gaynor, Martin Tracey A, Parr Christian, Watkins Gareth, Mason Malcolm D, Mansel Robert E
Metastasis and Angiogenesis Research Group, University Department of Surgery, Wales College of Medicine, Cardiff University, Cardiff, CF14 4XN, UK.
Int J Mol Med. 2006 Apr;17(4):583-90.
MT1-MMP (membrane type-1 matrix metalloproteinase), otherwise known as MMP14 is a proteolytic enzyme known to be involved in degradating extracellular matrix and assist progression of cancer invasion and progression. We investigated the impact of targeting the expression of MT1-MMP in breast cancer and its clinical relevance. Human breast cancer cell line MDA-MB-231 was used. Expression of MT1-MMP in the breast cancer cell line was manipulated by way of retroviral ribozyme transgene. The in vitro invasion, growth and cell migration were determined on cell lines transfected with either the transgene or control plasmid. Protein and message levels of MMP14 was also assessed using immunohistochemistry and real-time quantitative analysis, and correlated with clinical and pathological information of the patients. Retroviral ribozyme transgene to human MT1-MMP successfully knocked down the levels of MT1-MMP mRNA from MDA-MB-231 cells. Reduction of MT1-MMP from the breast cancer cells resulted in significant reduction of in vitro invasiveness and loss of response to an invasion stimulus, HGF, compared with control and wild-type cells. The invasion index for MT1-MMP knockdown cells were 13+/-3.1 (without HGF) and 16.4+/-2.3 (with HGF, p=0.14), and the index for transfection control cells 25.3+/-4.3 (without HGF) and 40.4+/-4.1 (with HGF, p=0.0049). Transfection with the transgenes did not change the rate of cell growth. In clinical breast cancer, MT1-MMP staining was both membranous and cytoplasmic. Tumour cells displayed stronger staining compared with normal mammary epithelial cells. Tumour tissues had a marginally higher levels of the MMP14 transcript (8.6+/-1.9), compared with normal tissues (4.7+/-1.4), p=0.13. No significant difference was observed between node positive and node negative tumours (9.0+/-2.2 vs 8.7+/-3.1, p=0.24). Marginally higher levels of the MMP14 transcript were seen in tumours which developed metastasis and local recurrence. However, tumours from patients who died of breast cancer related causes had significantly higher levels of the transcript, compared with tumours from patients who remained disease-free 10 years after initial surgery (12.2+/-2.5 vs 6.3+/-1.2, p=0.0091). MT1-MMP is a proteolytic enzyme that is pivotal in controlling the invasiveness of breast cancer cells. It is highly expressed in aggressive breast tumours and is associated with clinical outcome. The enzyme is a potential therapeutic target in breast cancer.
MT1-MMP（膜型-1基质金属蛋白酶），也被称为MMP14，是一种蛋白水解酶，已知其参与细胞外基质的降解，并促进癌症侵袭和进展。我们研究了靶向MT1-MMP在乳腺癌中的表达的影响及其临床相关性。使用了人乳腺癌细胞系MDA-MB-231。通过逆转录病毒核酶转基因来调控乳腺癌细胞系中MT1-MMP的表达。在转染了转基因或对照质粒的细胞系上测定体外侵袭、生长和细胞迁移情况。还使用免疫组织化学和实时定量分析评估MMP14的蛋白和信息水平，并将其与患者的临床和病理信息相关联。针对人MT1-MMP的逆转录病毒核酶转基因成功降低了MDA-MB-231细胞中MT1-MMP mRNA的水平。与对照细胞和野生型细胞相比，乳腺癌细胞中MT1-MMP的减少导致体外侵袭性显著降低，并丧失了对侵袭刺激物HGF的反应。MT1-MMP敲低细胞的侵袭指数在无HGF时为13±3.1，在有HGF时为16.4±2.3（p = 0.14），而转染对照细胞的指数在无HGF时为25.3±4.3，在有HGF时为40.4±4.1（p = 0.0049）。转基因转染并未改变细胞生长速率。在临床乳腺癌中，MT1-MMP染色呈膜性和胞质性。肿瘤细胞的染色比正常乳腺上皮细胞更强。肿瘤组织中MMP14转录本的水平略高于正常组织（8.6±1.9），正常组织为（4.7±1.4），p = 0.13。在淋巴结阳性和阴性肿瘤之间未观察到显著差异（9.0±2.2对8.7±3.1，p = 0.24）。在发生转移和局部复发的肿瘤中，MMP14转录本水平略高。然而，与初次手术后10年仍无疾病的患者的肿瘤相比，死于乳腺癌相关原因的患者的肿瘤转录本水平显著更高（12.2±2.5对6.3±1.2，p = 0.0091）。MT1-MMP是一种在控制乳腺癌细胞侵袭性方面起关键作用的蛋白水解酶。它在侵袭性乳腺癌中高表达，并与临床结果相关。该酶是乳腺癌中一个潜在的治疗靶点。
