Carbohydrate- Dependent Epithelial Cancer Metastasis

已有文献表明，上皮细胞的恶变与结构有关 细胞表面碳水化合物的变化。许多临床研究已经将这些与癌症相关的因素联系起来 糖类抗原临床预后差，包括转移。碳水化合物依赖型 已经观察到癌症转移，但这一过程背后的机制尚未确定。 我们先前通过以下方法鉴定了模拟抗Lewis A抗体表位的IELLQAR(L-肽) 筛选展示噬菌体文库的多肽。当将L多肽注射到野生型小鼠体内时，它们 抑制SLeX依赖的黑色素瘤肺定植。然而，肺定植也发生在突变型 E-选择素、P-选择素和L多肽缺乏的小鼠可抑制其定植，但不包括 这些选择素在这个过程中。这些发现表明，L多肽对定植的干扰确实 不需要E-和P-选择素。我们的初步数据表明，L多肽受体是前信使核糖核酸。 剪接因子(SFRS)和膜联蛋白AI(Anxal)。 PI还研究了高尔基体加工α-甘露糖苷酶II(MIL)和α-甘露糖苷酶在体内的作用 LLX(MX)。MIL/MX双零小鼠胚胎未显示复杂的A/-糖链， 说明MIL和MX共同参与了复合型N-糖链的合成。MIL/MX 双空体在出生后不久就是致命的。根据这些研究结果，具体目标如下： (1)用条件MIL/MX双空标法测定A/-葡聚糖L-选择素配体的体内活性 老鼠。内皮和造血细胞特异性MIL/MX双基因敲除(Tie2-Cre：Mllfaxp/Floxp/MX-/-) 将生成并分析高内皮微静脉(HEV)中L-选择素配体的活性，(2)到 定义SFRs和Anxal的碳水化合物结合活性，(3)确定靶向凋亡是否通过以下方式发生 安赛尔装订。Anxal已被确定为肿瘤特异的内皮标记物，我们发现了If肽， 优先与安慰剂结合。因此，我们将开发一种针对细胞凋亡的方法来 用IF-肽检测小鼠肿瘤血管内皮细胞，以及(4)测定Anxal 在内皮细胞表面表达促进血管生成和识别潜在的机制 依赖阿昔洛韦的内皮细胞激活，包括与硫酸乙酰肝素结合。 这些研究将为更好地理解潜在的机制提供信息 碳水化合物依赖的癌症转移和开发新的治疗策略 上皮癌。

It is well documented that malignant transformation of epithelial cells is associated with structural changes in cell surface carbohydrates. Many clinical studies have correlated those cancer-associated carbohydrate antigens with poor clinical prognosis, including metastasis. Carbohydrate-dependent cancer metastasis has been observed, but the mechanisms underlying this process are not yet defined. We previously identified IELLQAR (l-peptide) that mimics the epitope of anti-Lewis A antibody by screening peptide displaying phage libraries. When l-peptides were injected into wild type mice, they inhibited sLex-dependent melanoma lung colonization. However, lung colonization also occurs in mutant mice lacking both E- and P-selectins and l-peptide inhibits the colonization, excluding the involvement of these selectins in this process. These findings suggest that l-peptide interference with colonization does not require E- and P-selectins. Our preliminary data show that the l-peptide receptors are pre-mRNA splicing factor (Sfrs) and AnnexinAI (Anxal). The PI also studied the in vivo roles of the Golgi processing a-mannosidase II (Mil) and alphamannosidase llx (MX). Mil/MX double null mouse embryos showed no complex type A/-glycans, indicating that Mil and MX together are responsible for the complex type N-glycan synthesis. Mil/MX double nulls were lethal shortly after birth. Based on these findings, the specific aims are: (1) To determine A/-glycan-based L-selectin ligand activity in vivo using conditional Mil/MX double null mice. Endothelial and hematopoietic cell-specific Mil/MX double knockouts (Tie2-Cre:Mllftaxp/floxp/MX-/-) will be generated and analyzed for L-selectin ligand activity in high endothelial venules (HEVs), (2) to define carbohydrate-binding activity of Sfrs and Anxal, (3) to determine if targeted apoptosis occurs by Anxal binding. Anxal has been identified as a tumor-specific endothelial marker, and we identified IFpeptide, which binds preferentially to Anxal. Thus we will develop a method to target apoptosis to endothelial cells of tumor vasculature in the mouse using IF-peptide, and (4) to determine if Anxal expressed on the endothelial surface promotes angiogenesis and identify mechanisms underlying Anxal-dependent endothelial cell activation including binding to heparan sulfate. These studies will provide information for better understand of the mechanisms underlying carbohydrate-dependent cancer metastasis and help for developing new therapeutic strategies against epithelial cancer.