卵巢癌擁有婦癌當中最高的死亡率，關鍵因素之一為其早期症狀通常不明顯，導致多達七成患者確診時已達癌症晚期而有轉移的現象。其中，癌症轉移一直是癌症治療上最需要克服的障礙，了解卵巢癌轉移的機制以及發掘新的治療標的亦是目前非常重要的課題。為了探討造成卵巢癌轉移的機制，我們透過蛋白質體學配合二維差異電泳 (2D-DIGE) 與基質輔助雷射脫附游離飛行時間質譜儀 (MALDI-TOF MS) 分析高轉移能力細胞株TOV21GHI以及低轉移細胞株TOV21GLI間蛋白質的差異。結果顯示數個蛋白質的表現與癌症轉移有顯著關係，其中尿苷二磷酸葡萄糖脫氫酶 (UGDH) 大量表現於TOV21GHI細胞當中;組織微陣列亦顯示UGDH在臨床上大量表現於卵巢癌當中的透明細胞癌與黏液細胞癌，顯示該蛋白與卵巢癌轉移有密切關係。為了探討UGDH在卵巢癌轉移中所扮演的角色，我們利用核糖核酸干擾技術 (RNAi) 去抑制UGDH在細胞中的表現量。結果顯示在使用核糖核酸干擾降低TOV21GHI細胞內UGDH表現量後，細胞爬行、細胞侵襲以及傷口癒合能力顯著的下降;另外，核糖核酸干擾所造成的UGDH蛋白表現量下降也使得卵巢癌細胞週期發生停滯(cell cycle arrest)，更降低裸鼠動物實驗中腫瘤的生長速度。調控機制方面，我們發現UGDH表現量降低使ERK磷酸化程度下降、數種上皮間質轉換(EMT)因子以及基質金屬蛋白酶2(MMP2)的下降，最終促成細胞轉移功能的低下。總結，我們的研究發現UGDH在卵巢癌細胞轉移扮演重要角色及機轉，而UGDH在轉移的上抑制效果使其非常有潛力成為治療卵巢癌轉移的標的。

More than 70% of patients with ovarian cancer are diagnosed in advanced stages. Therefore, it is urgent to identify a promising prognostic marker and understand the mechanism of ovarian cancer metastasis development. By using proteomics approaches, we found that UDP-glucose dehydrogenase (UGDH) was upregulated in highly metastatic ovarian cancer TOV21G cells, characterized by high invasiveness (TOV21GHI), in comparison to its parental control. UGDH catalyzes the biosynthetic oxidation of UDP-glucose to UDP-glucuronic acid, which is a critical step in glycosaminoglycan synthesis. Previous reports demonstrated that UGDH is involved in cell migration, but its specific role in cancer metastasis remains unclear. By performing immunohistochemical staining with tissue microarray, we found overexpression of UGDH in ovarian cancer tissue, but not in normal adjacent tissue. Silencing using RNA interference (RNAi) was utilized to knockdown UGDH, which resulted in a significant decrease in metastatic ability in Transwell migration, Transwell invasion and wound healing assays. The knockdown of UGDH caused cell cycle arrest in the G0/G1 phase and induced a massive decrease of tumor formation rate in vivo. Our data showed that UGDH-depletion led to the downregulation of epithelial-mesenchymal transition (EMT)-related markers as well as MMP2, and inactivation of the ERK/MAPK pathway. In conclusion, we found that the upregulation of UGDH is related to ovarian cancer metastasis and the deficiency of UGDH leads to the decrease of cell migration, cell invasion, wound healing, and cell proliferation ability. Our findings reveal that UGDH can serve as a prognostic marker and that the inhibition of UGDH is a promising strategy for ovarian cancer treatment.

1. Reid, B.M., J.B. Permuth, and T.A. Sellers, Epidemiology of ovarian cancer: a review. Cancer Biol Med, 2017. 14(1): p. 9-32.
2. Naora, H. and D.J. Montell, Ovarian cancer metastasis: integrating insights from disparate model organisms. Nat Rev Cancer, 2005. 5(5): p. 355-66.
3. Allemani, C., et al., Global surveillance of cancer survival 1995-2009: analysis of individual data for 25,676,887 patients from 279 population-based registries in 67 countries (CONCORD-2). Lancet, 2015. 385(9972): p. 977-1010.
4. Whitwell, H.J., et al., Improved early detection of ovarian cancer using longitudinal multimarker models. Br J Cancer, 2020. 122(6): p. 847-856.
5. Nolen, B.M. and A.E. Lokshin, Protein biomarkers of ovarian cancer: the forest and the trees. Future Oncol, 2012. 8(1): p. 55-71.
6. Neesham, D., Ovarian cancer screening. Aust Fam Physician, 2007. 36(3): p. 126-8.
7. Lengyel, E., Ovarian cancer development and metastasis. Am J Pathol, 2010. 177(3): p. 1053-64.
8. Cortez, A.J., et al., Advances in ovarian cancer therapy. Cancer Chemother Pharmacol, 2018. 81(1): p. 17-38.
9. Orr, B. and R.P. Edwards, Diagnosis and Treatment of Ovarian Cancer. Hematol Oncol Clin North Am, 2018. 32(6): p. 943-964.
10. Vetter, M.H. and J.L. Hays, Use of Targeted Therapeutics in Epithelial Ovarian Cancer: A Review of Current Literature and Future Directions. Clinical Therapeutics, 2018. 40(3): p. 361-371.
11. Kim, J.Y., C.H. Cho, and H.S. Song, Targeted therapy of ovarian cancer including immune check point inhibitor. Korean J Intern Med, 2017. 32(5): p. 798-804.
12. Shao, F.P., et al., Efficacy and safety of PARP inhibitors as the maintenance therapy in ovarian cancer: a meta-analysis of nine randomized controlled trials. Bioscience Reports, 2020. 40.
13. Martinez, A., et al., Preclinical and Clinical Immunotherapeutic Strategies in Epithelial Ovarian Cancer. Cancers (Basel), 2020. 12(7).
14. Guan, X., Cancer metastases: challenges and opportunities. Acta Pharm Sin B, 2015. 5(5): p. 402-18.
15. Valastyan, S. and R.A. Weinberg, Tumor metastasis: molecular insights and evolving paradigms. Cell, 2011. 147(2): p. 275-92.
16. Lambert, A.W., D.R. Pattabiraman, and R.A. Weinberg, Emerging Biological Principles of Metastasis. Cell, 2017. 168(4): p. 670-691.
17. Thiery, J.P., et al., Epithelial-mesenchymal transitions in development and disease. Cell, 2009. 139(5): p. 871-90.
18. D'Angelo, G., et al., Glycosphingolipids: synthesis and functions. FEBS J, 2013. 280(24): p. 6338-53.
19. Cheng, J.Y., et al., Globo-H ceramide shed from cancer cells triggers translin-associated factor X-dependent angiogenesis. Cancer Res, 2014. 74(23): p. 6856-66.
20. Chang, W.W., et al., Expression of Globo H and SSEA3 in breast cancer stem cells and the involvement of fucosyl transferases 1 and 2 in Globo H synthesis. Proc Natl Acad Sci U S A, 2008. 105(33): p. 11667-72.
21. Meleady, P., Two-Dimensional Gel Electrophoresis and 2D-DIGE. Methods Mol Biol, 2018. 1664: p. 3-14.
22. Kondo, T., Cancer biomarker development and two-dimensional difference gel electrophoresis (2D-DIGE). Biochim Biophys Acta Proteins Proteom, 2019. 1867(1): p. 2-8.
23. Lin, L.H., et al., Biomarker discovery for neuroendocrine cervical cancer. Electrophoresis, 2014. 35(14): p. 2039-45.
24. Arnold, J.M., et al., UDP-glucose 6-dehydrogenase regulates hyaluronic acid production and promotes breast cancer progression. Oncogene, 2019.
25. Wang, T.P., et al., Down-regulation of UDP-glucose dehydrogenase affects glycosaminoglycans synthesis and motility in HCT-8 colorectal carcinoma cells. Experimental Cell Research, 2010. 316(17): p. 2893-2902.
26. Oyinlade, O., et al., Targeting UDP-alpha-D-glucose 6-dehydrogenase inhibits glioblastoma growth and migration. Oncogene, 2018. 37(20): p. 2615-2629.
27. Wang, X., et al., UDP-glucose accelerates SNAI1 mRNA decay and impairs lung cancer metastasis. Nature, 2019. 571(7763): p. 127-131.
28. Chuang, P.K., et al., Signaling pathway of globo-series glycosphingolipids and beta1,3-galactosyltransferase V (beta3GalT5) in breast cancer. Proc Natl Acad Sci U S A, 2019. 116(9): p. 3518-3523.
29. Roche, J., The Epithelial-to-Mesenchymal Transition in Cancer. Cancers (Basel), 2018. 10(2).
30. Wang, S., et al., Matrix Metalloproteinase Expressions Play Important role in Prediction of Ovarian Cancer Outcome. Sci Rep, 2019. 9(1): p. 11677.
31. Yamaguchi, H. and J. Condeelis, Regulation of the actin cytoskeleton in cancer cell migration and invasion. Biochim Biophys Acta, 2007. 1773(5): p. 642-52.
32. Tang, D.D. and B.D. Gerlach, The roles and regulation of the actin cytoskeleton, intermediate filaments and microtubules in smooth muscle cell migration. Respir Res, 2017. 18(1): p. 54.
33. Maneix, L., et al., 17Beta-oestradiol up-regulates the expression of a functional UDP-glucose dehydrogenase in articular chondrocytes: comparison with effects of cytokines and growth factors. Rheumatology (Oxford), 2008. 47(3): p. 281-8.
34. Wen, Y., et al., UDP-glucose dehydrogenase modulates proteoglycan synthesis in articular chondrocytes: its possible involvement and regulation in osteoarthritis. Arthritis Res Ther, 2014. 16(6): p. 484.
35. Finley, L.W.S., Metabolic signal curbs cancer-cell migration. Nature, 2019. 571(7763): p. 39-40.
36. Hwang, E.Y., et al., Inhibitory effects of gallic acid and quercetin on UDP-glucose dehydrogenase activity. FEBS Lett, 2008. 582(27): p. 3793-7.
37. Muys, B.R., et al., miR-450a Acts as a Tumor Suppressor in Ovarian Cancer by Regulating Energy Metabolism. Cancer Research, 2019. 79(13): p. 3294-3305.
38. Zhao, W., et al., miR-552 promotes ovarian cancer progression by regulating PTEN pathway. J Ovarian Res, 2019. 12(1): p. 121.
39. Diab, Y. and M.Z. Muallem, Targeted Therapy in Ovarian Cancer. A Comprehensive Systematic Review of Literature. Anticancer Res, 2017. 37(6): p. 2809-2815.
40. Rossi, L., et al., Bevacizumab in ovarian cancer: A critical review of phase III studies. Oncotarget, 2017. 8(7): p. 12389-12405.
41. Chase, D.M., D.J. Chaplin, and B.J. Monk, The development and use of vascular targeted therapy in ovarian cancer. Gynecologic Oncology, 2017. 145(2): p. 393-406.
42. Menard, S., et al., Generation of monoclonal antibodies reacting with normal and cancer cells of human breast. Cancer Res, 1983. 43(3): p. 1295-300.
43. Bremer, E.G., et al., Characterization of a glycosphingolipid antigen defined by the monoclonal antibody MBr1 expressed in normal and neoplastic epithelial cells of human mammary gland. J Biol Chem, 1984. 259(23): p. 14773-7.
44. Seo, A., et al., Inherited thrombocytopenia associated with mutation of UDP-galactose-4-epimerase (GALE). Hum Mol Genet, 2019. 28(1): p. 133-142.
45. Demirbas, D., et al., Hereditary galactosemia. Metabolism, 2018. 83: p. 188-196.
46. de Souza, M.D.D., et al., Overexpression of UDP-Glucose 4-Epimerase Is Associated with Differentiation Grade of Gastric Cancer. Disease Markers, 2019. 2019.
47. Sun, X., et al., GALE Promotes the Proliferation and Migration of Glioblastoma Cells and Is Regulated by miR-let-7i-5p. Cancer Manag Res, 2019. 11: p. 10539-10554.
48. Bauer, C.H., et al., Alterations of D-galactose metabolism in Morris hepatomas. Cancer Res, 1980. 40(6): p. 2026-32.
49. da Silveira Mitteldorf, C.A., et al., FN1, GALE, MET, and QPCT overexpression in papillary thyroid carcinoma: molecular analysis using frozen tissue and routine fine-needle aspiration biopsy samples. Diagn Cytopathol, 2011. 39(8): p. 556-61.
50. Blanchard, H., et al., Galectin-1 inhibitors and their potential therapeutic applications: a patent review. Expert Opinion on Therapeutic Patents, 2016. 26(5): p. 537-554.
51. Bacigalupo, M.L., P. Carabias, and M.F. Troncoso, Contribution of galectin-1, a glycan-binding protein, to gastrointestinal tumor progression. World J Gastroenterol, 2017. 23(29): p. 5266-5281.
52. Li, J.M., et al., Upregulation of LGALS1 is associated with oral cancer metastasis. Therapeutic Advances in Medical Oncology, 2018. 10: p. 1-20.
53. Thijssen, V.L., et al., Galectin expression in cancer diagnosis and prognosis: A systematic review. Biochim Biophys Acta, 2015. 1855(2): p. 235-47.
54. Kim, H.J., et al., High galectin-1 expression correlates with poor prognosis and is involved in epithelial ovarian cancer proliferation and invasion. Eur J Cancer, 2012. 48(12): p. 1914-21.
55. Zhu, J., et al., Galectin-1 induces metastasis and epithelial-mesenchymal transition (EMT) in human ovarian cancer cells via activation of the MAPK JNK/p38 signalling pathway. Am J Transl Res, 2019. 11(6): p. 3862-3878.
56. Zhang, P., et al., Galectin-1 overexpression promotes progression and chemoresistance to cisplatin in epithelial ovarian cancer. Cell Death Dis, 2014. 5: p. e991.
57. Huang, D.L., et al., UDP-glucose dehydrogenase as a novel field-specific candidate biomarker of prostate cancer. International Journal of Cancer, 2010. 126(2): p. 315-327.
58. Uhlen, M., et al., Proteomics. Tissue-based map of the human proteome. Science, 2015. 347(6220): p. 1260419.
59. Kossai, M., et al., Ovarian Cancer: A Heterogeneous Disease. Pathobiology, 2018. 85(1-2): p. 41-49.
60. Kurman, R.J. and M. Shih Ie, Molecular pathogenesis and extraovarian origin of epithelial ovarian cancer--shifting the paradigm. Hum Pathol, 2011. 42(7): p. 918-31.
61. Ricci, F., et al., Recent Insights into Mucinous Ovarian Carcinoma. International Journal of Molecular Sciences, 2018. 19(6).
62. Chan, J.K., et al., Do clear cell ovarian carcinomas have poorer prognosis compared to other epithelial cell types? A study of 1411 clear cell ovarian cancers. Gynecologic Oncology, 2008. 109(3): p. 370-376.
63. Hallas-Potts, A., J.C. Dawson, and C.S. Herrington, Ovarian cancer cell lines derived from non-serous carcinomas migrate and invade more aggressively than those derived from high-grade serous carcinomas. Scientific Reports, 2019. 9.
64. Xue, Q., et al., Penfluridol: An antipsychotic agent suppresses lung cancer cell growth and metastasis by inducing G0/G1 arrest and apoptosis. Biomed Pharmacother, 2020. 121: p. 109598.
65. Evron, E., et al., Loss of cyclin D2 expression in the majority of breast cancers is associated with promoter hypermethylation. Cancer Res, 2001. 61(6): p. 2782-7.
66. Matsubayashi, H., et al., Methylation of cyclin D2 is observed frequently in pancreatic cancer but is also an age-related phenomenon in gastrointestinal tissues. Clin Cancer Res, 2003. 9(4): p. 1446-52.
67. Padar, A., et al., Inactivation of cyclin D2 gene in prostate cancers by aberrant promoter methylation. Clin Cancer Res, 2003. 9(13): p. 4730-4.
68. Ding, Z.Y., et al., Prognostic role of cyclin D2/D3 in multiple human malignant neoplasms: A systematic review and meta-analysis. Cancer Med, 2019. 8(6): p. 2717-2729.
69. Wang, L., et al., The Silencing of CCND2 by Promoter Aberrant Methylation in Renal Cell Cancer and Analysis of the Correlation between CCND2 Methylation Status and Clinical Features. PLoS One, 2016. 11(9): p. e0161859.
70. Meyyappan, M., et al., Increased expression of cyclin D2 during multiple states of growth arrest in primary and established cells. Mol Cell Biol, 1998. 18(6): p. 3163-72.
71. Aroui, S., et al., Naringin suppresses cell metastasis and the expression of matrix metalloproteinases (MMP-2 and MMP-9) via the inhibition of ERK-P38-JNK signaling pathway in human glioblastoma. Chem Biol Interact, 2016. 244: p. 195-203.
72. Clarkin, C.E., et al., Regulation of UDP-glucose dehydrogenase is sufficient to modulate hyaluronan production and release, control sulfated GAG synthesis, and promote chondrogenesis. J Cell Physiol, 2011. 226(3): p. 749-61.
73. Xiao, L.J., et al., ADAM17 targets MMP-2 and MMP-9 via EGFR-MEK-ERK pathway activation to promote prostate cancer cell invasion. Int J Oncol, 2012. 40(5): p. 1714-24.
74. Al-Alem, L. and T.E. Curry, Jr., Ovarian cancer: involvement of the matrix metalloproteinases. Reproduction, 2015. 150(2): p. R55-64.
75. Kenny, H.A., et al., The initial steps of ovarian cancer cell metastasis are mediated by MMP-2 cleavage of vitronectin and fibronectin. J Clin Invest, 2008. 118(4): p. 1367-79.
76. Hu, X., et al., Matrix metalloproteinase-9 expression correlates with prognosis and involved in ovarian cancer cell invasion. Arch Gynecol Obstet, 2012. 286(6): p. 1537-43.
77. Zhang, R., et al., MicroRNA-338-3p suppresses ovarian cancer cells growth and metastasis: implication of Wnt/catenin beta and MEK/ERK signaling pathways. J Exp Clin Cancer Res, 2019. 38(1): p. 494.
78. Zhang, L., et al., Tanshinone IIA reverses EGF- and TGF-beta1-mediated epithelial-mesenchymal transition in HepG2 cells via the PI3K/Akt/ERK signaling pathway. Oncol Lett, 2019. 18(6): p. 6554-6562.
79. Geng, X.Q., et al., Ganoderic acid hinders renal fibrosis via suppressing the TGF-beta/Smad and MAPK signaling pathways. Acta Pharmacol Sin, 2019.
80. Grady, G., et al., Inhibiting Hexamer Disassembly of Human UDP-Glucose Dehydrogenase by Photoactivated Amino Acid Cross-Linking. Biochemistry, 2016. 55(22): p. 3157-64.
81. Afratis, N., et al., Glycosaminoglycans: key players in cancer cell biology and treatment. FEBS J, 2012. 279(7): p. 1177-97.
82. Morla, S., Glycosaminoglycans and Glycosaminoglycan Mimetics in Cancer and Inflammation. Int J Mol Sci, 2019. 20(8).
83. Strutz, F., et al., Role of basic fibroblast growth factor-2 in epithelial-mesenchymal transformation. Kidney Int, 2002. 61(5): p. 1714-28.
84. Mundhenke, C., et al., Heparan sulfate proteoglycans as regulators of fibroblast growth factor-2 receptor binding in breast carcinomas. American Journal of Pathology, 2002. 160(1): p. 185-194.
85. Hallou, A., J. Jennings, and A.J. Kabla, Tumour heterogeneity promotes collective invasion and cancer metastatic dissemination. R Soc Open Sci, 2017. 4(8): p. 161007.
86. Roberts, C.M., C. Cardenas, and R. Tedja, The Role of Intra-Tumoral Heterogeneity and Its Clinical Relevance in Epithelial Ovarian Cancer Recurrence and Metastasis. Cancers (Basel), 2019. 11(8).
87. Hanahan, D. and R.A. Weinberg, Hallmarks of cancer: the next generation. Cell, 2011. 144(5): p. 646-74.
88. Ince, T.A., et al., Characterization of twenty-five ovarian tumour cell lines that phenocopy primary tumours. Nature Communications, 2015. 6.
89. Domcke, S., et al., Evaluating cell lines as tumour models by comparison of genomic profiles. Nature Communications, 2013. 4.
90. Wu, C.S., et al., Downregulation of microRNA-15b by hepatitis B virus X enhances hepatocellular carcinoma proliferation via fucosyltransferase 2-induced Globo H expression. Int J Cancer, 2014. 134(7): p. 1638-47.