人類凝血酶調節素 (TM) 是一個表現於血管內皮細胞表面的醣蛋白，由五個功能區域所構成，包含N-terminal lectin-like domain (TMD1)，EGF-like domain (TMD2) ， serine and theronine-rich domain (TMD3)， transmembrane domain (TMD4) ，以及 C-terminal cytoplasmic domain (TMD5)。TM最早被報導是具有能調控凝血機制的因子，然而在後來的研究，卻發現TM不只是表現在血管的內皮細胞，而且也表現在血管以外的其他細胞上。另外TM也被發現具有調控細胞之間連結、刺激血管新生、抗發炎及抑制癌生長的功能。Endosialin在序列與結構上與TM具有高度的相似性，然而直至目前為止，endosialin的生物功能尚未被研究清楚。由先前的研究，我們發現TMD1可能有抑制癌轉移的能力。在本篇研究，我們利用了反轉錄聚合酶連鎖反應，分析了endosialin、TM與CD93在不同細胞株的表現量，接著檢測內生性endosialin的表現情況。我們亦構築了TM跟endosialin 之lectin-like domain的重組蛋白 (TMD1及ESD1) ，經由哺乳動物細胞及酵母菌系統大量表現並純化之，利用TMD1及ESD1去施打老鼠後，發現皆能抑制小鼠黑色素瘤細胞的轉移能力，但並不直接影響小鼠黑色素瘤細胞的生長速率。

Thrombomodulin (TM), a glycoprotein on vascular endothelial cell surfaces, is structurally composed of five domains: N-terminal lectin-like domain (TMD1), EGF-like domain (TMD2), serine and threonine-rich domain (TMD3), transmembrane domain (TMD4), and a C-terminal cytoplasmic domain (TMD5). TM functions as a cofactor to modulate coagulation. However, previous studies have revealed that TM is not only found on vascular endothelial cells but also expressed at extravascular sites. In previous studies, TM was found to regulate cell-cell adhesion, induce angiogenesis, modulate inflammation, and inhibit cancer growth. Endosialin has high homology to TM by structural comparison and sequence alignment, but the biological functions of endosialin are still not clear. In previous studies, we have found the TMD1 may possess anti-cancer metastatic activity. In this study, we first analyzed the expression level of eodosialin, TM and CD93 in different cells by Reverse Transcriptase-Polymerase Chain Reaction. The expression patterns of endogenous endosialin were dissected . The lectin-like domain of TM (TMD1) and endosialin (ESD1) were constructed, expressed and purified. We tested the anti-cancer metastatic activity of TMD1 and ESD1 using the mice metastasis model. We found that TMD1 and ESD1 could effectively inhibit the metastastic ability of mice melanoma cells, but did not affect the growth rate of mice melanoma cells.

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