B3GNT2, a Polylactosamine Synthase, Regulates Glycosylation of EGFR in H7721 Human Hepatocellular Carcinoma Cells

  • Qiu, Hao (Department of Biochemistry and Molecular Biology, Medical School of Soochow University) ;
  • Duan, Wei-Ming (Department of Oncology, The First Affiliated Hospital of Soochow University) ;
  • Shu, Jie (Department of Biochemistry and Molecular Biology, Medical School of Soochow University) ;
  • Cheng, Hong-Xia (Department of Biochemistry and Molecular Biology, Medical School of Soochow University) ;
  • Wang, Wei-Ping (Department of Biochemistry and Molecular Biology, Medical School of Soochow University) ;
  • Huang, Xin-En (Jiangsu Cancer Hospital & Research Institute) ;
  • Chen, Hui-Li (Department of Biochemistry and Molecular Biology, Medical School of Soochow University)
  • Published : 2015.01.22


The epidermal growth factor receptor (EGFR) is an important surface receptor with N-glycans in its extracellular domain, whose glycosylation is essential for its function, especially in tumor cells. Here, we demonstrated that polylactosamine is markedly increased in H7721 hepatocellular carcinoma cells after treatment with EGF, while it apparently declined after exposure to all-trans retinoic acid (ATRA). In the study of the enzymatic mechanism of this phenomenon, we explored changes in the expression of poly-N-acetyllactosamine (PLN) branching glycosyltransferases using RT-PCR. Among the four glycosyltransferases with altered expression, GnT-V was most elevated by EGF, while GnT-V and B3GNT2 were most declined by ATRA. Next, we conducted co-immunoprecipitation experiments to test whether B3GNT2 and EGFR associate with each other. We observed that EGFR is a B3GNT2-targeting protein in H7721 cells. Taken together, these findings indicated that the altered expression of B3GNT2 will remodel the PLN stucture of EGFR in H7721 cells, which may modify downstream signal transduction.


Supported by : National Nature Science Foundation of China


  1. Akira T, Yuko K, Hiroyasu I, et al (2007). Polylactosamine on glycoproteins influences basal levels of lymphocyte and macrophage activation. Proc Natl Acad Sci USA, 104, 15829-34.
  2. Andreea C, Anca C, Raluca C, et al (2014). Crosstalk between EGFR and p53 in hepatocellular carcinoma. Asian Pac J Cancer Prev, 15, 8069-73.
  3. Bishayee S (2000). Role of conformational alteration in the epidermal growth factor receptor (EGFR) function. Biochem Pharmacol, 60, 1217-23.
  4. Bosetti C, Turati F, La Vecchia C (2014). Hepatocellular carcinoma epidemiology. Best Pract Res Clin Gastroenterol, 28, 753-70.
  5. Dall'Olio F (2000). The sialyl-alpha2, 6-lactosaminyl-structure: Biosynthesis and functional role. Glycoconj J, 17, 669-76.
  6. Dube DH, Bertozzi CR. Glycans in cancer and inflammation- Potential for therapeutics and diagnostics. Nat Rev Drug Discov, 4, 477-88.
  7. Elola MT, Chiesa ME, Alberti AF, et al (2005). Galectin-1 receptors in different cell types. J Biomed Sci, 12, 13-29.
  8. Greenfield C, Hiles I, Waterfield MD, et al (1989). Epidermal growth factor binding induces a conformational change in the external domain of its receptor. Embo J, 8, 4115-23.
  9. Guo HB, Johnson H, Randolph M, et al (2009). Knockdown of GnT-Va expression inhibits ligand-induced downregulation of the epidermal growth factor receptor and intracellular signaling by inhibiting receptor endocytosis. Glycobiology, 19, 547-59.
  10. Guo P, Wang QY, Guo HB, et al (2004). N-Acetylglucosaminyltransferase V modifies the signaling pathway of epidermal growth factor receptor. Cell Mol Life Sci, 61, 1795-804.
  11. Guo P, Chen HJ, Wang QY, et al (2005). Down regulation of N-acetylglucosaminyltransferase V facilitates all-trans retinoic acid to induce apoptosis of human hepatocarcinoma cells. Mol Cell Biochemis, 284, 103-10.
  12. Hakomori S (1999). Antigen structure and genetic basis of histo-blood groups A, B and O: Their changes associated with human cancer. Biochim Biophys Acta, 1473, 247-66.
  13. Kasai K, Hirabayashi J (1996). Galectins: Afamily of animal lectins that decipher glycocodes. J Biochem, 119, 1-8.
  14. Keating E, Nohe A, Petersen NO (2008). Studies of distribution, location and dynamic properties of EGFR on the cell surface measured by image correlation spectroscopy. Eur Biophys J, 37, 469-81.
  15. Lemmon MA, Bu Z, Ladbury JE, et al (1997). Two EGF molecules contribute additively to stabilization of the EGFR dimer. Embo J, 16, 281-94.
  16. Liu J, Liu H, Zhang W, et al (2013). N-acetylglucosaminyltransferase V confers hepatoma cells with resistance to anoikis through EGFR/PAK1 activation. Glycobiology, 23, 1097-109.
  17. Peter LL, Jennifer JK, Suzanne RP (2009). Association of ${\beta}-1$, 3-N-acetylglucosaminyltransferase 1 and ${\beta}-1$, 4-galactosyltransferase 1, trans-Golgi enzymes involved in coupled poly-N-acetyllactosamine synthesis. Glycobiology, 19, 655-64.
  18. Sebastian S, Settleman J, Reshkin SJ, et al (2006). The complexity of targeting EGFR signalling in cancer: From expression to turnover. Biochim Biophys Acta. 1766, 120-39.
  19. Soderquist AM, Todderud G, Carpenter G (1988). The role of carbohydrate as a post-translational modification of the receptor for epidermal growth factor. Adv Exp Med Biol, 231, 569-82.
  20. Sun QC, Liu MB, Shen HJ, et al (2013). Inhibition by Imatinib of expression of o-glycan-related glycosyltransferases and tumor-associated carbohydrate antigens in the K562 human leukemia cell line. Asian Pac J Cancer Prev, 14, 2447-51.
  21. Takahashi M, Yokoe S, Asahi M, et al (2008). N-glycan of ErbB family plays a crucial role in dimer formation and tumor promotion. Biochim Biophys Acta, 1780, 520-4.
  22. Togayachi A, Kozono Y, Kuno A, et al (2010). Beta3GnT2 (B3GNT2), a major polylactosamine synthase: analysis of B3GNT2-deficient mice. Methods Enzymol, 479, 185-204.
  23. Tsuda T, Ikeda Y, Taniguchi N (2000). The Asn-420-linked sugar chain in human epidermal growth factor receptor suppresses ligand-independent spontaneous oligomerization. Possible role of a specific sugar chain in controllable receptor activation. J Biol Chem, 275, 21988-94.
  24. Ullrich A, Coussens L, Hayflick JS, et al (1984). Human epidermal growth factor receptor cDNA sequence and aberrant expression of the amplified gene in A431 epidermoid carcinoma cells. Nature, 309, 418-25.
  25. Zhou D (2003). Why are glycoproteins modified by poly-Nacetyllactosamine glyco-conjugates? Curr Protein Pept Sci, 4, 1-9.