ASN-LINKED OLIGOSACCHARIDES IN LECTIN-RESISTANT TUMOR-CELL MUTANTS WITH VARYING METASTATIC POTENTIAL
ASN-LINKED OLIGOSACCHARIDES IN LECTIN-RESISTANT TUMOR-CELL MUTANTS WITH VARYING METASTATIC POTENTIAL
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DOI：
10.1111/j.1432-1033.1986.tb10455.x
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发表时间：
1986-12-01
期刊：
影响因子：
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通讯作者：
CARVER, JP
中科院分区：
文献类型：
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作者：
DENNIS, JW;LAFERTE, S;CARVER, JP
MDW 4是转移性鼠肿瘤MDAY D2的麦胚凝集素抗性突变体，先前已显示当静脉内注射到同基因小鼠中时转移性差，而当皮下注射到同基因小鼠中时无转移性。W 4 EB 8是MDW 4的一种经凝集素选择的MDW 4亚系，其对凝集素的敏感性和静脉注射小鼠时的转移表型介于MDAY-D2和MDW 4细胞之间。MDAY-D2、MDW 4和W 4 EB 8细胞中Asn连接的寡糖用肽N-糖苷酶酶解，用氚化硼氢化钠还原，并通过Concanavalin-A-Sepharose亲和层析和高效液相色谱（HPLC）分级分离。通过糖苷酶消化和大小，气液色谱/质谱法和质子核磁共振相结合的主要馏分的结构进行了测定。野生型和突变型细胞将高甘露糖型结构加工成双触角（GlcNAc）2（Man）3（GlcNAc）2。在MDAY-D2细胞中，该结构被进一步加工成唾液酸化的四触角复合物，其具有终止于唾液酸或α 1 -3-连接的半乳糖的含聚乳糖胺的触角。MDW 4细胞具有比MDAY-D2细胞多四倍或五倍的（GlcNAc）2（Man）3（GlcNAc）2和在野生型细胞中未发现的三触角（GlcNAc）3（Man）3（GlcNAc）2（即2，2，6-取代的三甘露糖基核心）的主要组分。部分回复突变体W 4 EB 8具有中间水平的突变体（GlcNAc）3（Man）3（GlcNAc）2和唾液酸化复合型碳水化合物。结果表明，在实验转移测定中，肿瘤细胞中从不完全复合型到唾液酸化的三-四-触角复合型碳水化合物的表达的转变可增强肿瘤细胞的转移潜力。此外，体细胞杂交分析表明，MDW 4细胞的缺陷与中国仓鼠卵巢突变体Lec 8的缺陷相同：UDP-半乳糖转运到高尔基体中的缺陷。
MDW4, a wheat germ agglutinin-resistant mutant of the metastatic murine tumor MDAY D2 has previously been shown to be poorly metastatic when injected intravenously and non-metastatic when injected subcutaneously into syngeneic mice. W4EB8, a Bandeiraea simplicifolia (BSII) lectin-selected subline of MDW4 has previously been shown to be intermediate between that of MDAY-D2 and MDW4 cell for sensitivity to lectin and metastatic phenotype when injected intravenously into mice. The Asn-linked oligosaccharides from MDAY-D2, MDW4 and W4EB8 cells were released enzymatically with peptide N-glycosidase, reduced with tritiated sodium borohydride and fractionated by Concanavalin-A-Sepharose affinity chromatography and high-performance liquid chromatography (HPLC). Structures of the major fractions were determined by a combination of glycosidase digestion and sizing, gas-liquid chromatography/mass spectrometry and by proton nuclear magnetic resonance. Wild-type and mutant cells processed high-mannose-type structures to biantennary (GlcNAc)2(Man)3(GlcNAc)2. In MDAY-D2 cells this structure was processed further to sialylated tetra-antennary complex with polylactosamine-containing antennae terminating in either sialic acid or .alpha.1-3-linked galactose. MDW4 cells had four or five times more (GlcNAc)2(Man)3(GlcNAc)2 than MDAY-D2 cells and a major component of tri-antennary (GlcNAc)3(Man)3(GlcNAc)2 (i.e. 2,2,6-substituted tri-mannosyl core) that was not found in wild-type cells. The partial revertant, W4EB8 had intermediate levels of mutant (GlcNAc)3(Man)3(GlcNAc)2 and sialylated complex-type carbohydrates. The results indicate that a shift in expression from incomplete complex type to sialylated tri-tetra-antennary complex-type carbohydrates in tumor cell may enhance the metastatic potential of tumor cells in the experimental metastasis assay. In addition, somatic cell hybridization analysis indicated that the defect in MDW4 cells was identical to that of the Chinese hamster ovary mutant Lec8: a deficiency in UDP-galactose transport into the golgi.