Transcriptional regulation of E-cadherin and oncoprotein E7 by valproic acid in HPV positive cell lines

Document Type : Original Article


1 Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

2 Colorectal Research Center, Iran University of Medical Sciences, Tehran, Iran

3 Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran


Objective(s): Valproic acid (VPA) has proven to be as one of the most promising useful drug with anticancer properties.In this study, we investigate the VPA effects on E-cadherin expression in HeLa, TC1, MKN45, and HCT116 cell lines.  This study assesses the effects of VPA on human papillomavirus E7 expression in HPV positive cell lines.
Materials and Methods: Cell lines were treated by2 mmol/l VPA and expression of E-cadherin and E7 was analyzed by quantitative real-time PCR. Student’s t test and ANOVA were used to determine changes in expression levels.
Results:The results revealed that mean of E-cadherin expression is increased by VPA 1.8 times in HCT116 and MKN45 cell lines, also the mean of E-cadherin mRNA levels is up-regulated 2.9 times in HeLa and TC1 cell lines. So, E-cadherin augmentation induced by VPA in HeLa and TC-1, HPV positive cell lines, is higher than HPV negative cell lines MKN45 and HCT116. The mean of HPV E7 expression is decreased by VPA, 4.6 times in in HeLa and TC-1 cell lines. 
Conclusion: This study demonstrates that re-expression of E-cadherin by VPA in HPV positive cell lines is more than HPV negative cell lines. Whereas, HPV E7 reduces the expression of E-cadherin, reduction of HPV E7 expression by VPA is related to more augmentation of E-cadherin in HPV positive cell lines. So, this study demonstrates that VPA has more anticancer properties in HPV positive cell lines, and could potentially be a promising candidate for cervical cancer treatment.


1. Pisani P, Bray F, Parkin DM. Estimates of the world-wide prevalence of cancer for 25 sites in the adult population. Int J Cancer 2002; 97:72-81.
2. Rossi A, Ciafre S, Balsamo M, Pierimarchi P, Santoro MG. Targeting the heat shock factor 1 by RNA interference: a potent tool to enhance hyper thermo chemotherapy efficacy in cervical cancer. Cancer Res 2006; 66:7678–7685.
3. Cogliano V, Baan R, Straif K, Grosse Y, Secretan B, El Ghissassi F. Carcinogenicity of human papilloma-viruses. Lancet Oncol 2005; 6:204.
4. zur Hausen H. Papillomaviruses and cancer: from basic studies to clinical application. Nat Rev Cancer 2002; 2:342-3450.
5. Boyer SN, Wazer DE, Band V. E7 protein of human papilloma virus-16 induces degradation of retinoblastoma protein through the ubiquitin-proteasome pathway. Cancer Res 1996; 56:4620-4624.
6. Scheffner M, Werness BA, Huibregtse JM, Levine AJ, Howley PM. The E6 oncoprotein encoded by human papillomavirus types 16 and 18 promotes the degradation of p53. Cell 1990; 63:1129-1136.
7. Gonzalez Martin A. Molecular biology of cervical cancer. Clin Transl Oncol 2007; 9:347-354.
8. Ellis L, Atadja PW, Johnstone RW. Epigenetics in cancer: targeting chromatin modifications. Mol Cancer Ther 2009; 8:1409-1420.
9. Wang GG, Allis CD, Chi P. Chromatin remodeling and cancer, Part I: covalent histone modifications. Trends Mol Med 2007; 13:363-372.
10. Marks P, Rifkind RA, Richon VM, Breslow R, Miller T, Kelly WK. Histone deacetylases and cancer: causes and therapies. Nat Rev Cancer 2001; 1:194-202.
11. Bellarosa D, Bressan A, Bigioni M, Parlani M, Maggi CA, Binaschi M. SAHA/ Vorinostat induces the expression of the CD137 receptor/ ligand system and enhances apoptosis mediated by soluble CD137 receptor in a human breast cancer cell line. Int J Oncol 2012; 41:1486-1494.
12. Feng L, Pan M, Sun J, Lu H, Shen Q, Zhang S, et al. Histone deacetylase 3 inhibits expression of PUMA in gastric cancer cells. J Mol Med 2013; 91:49-58.
13. Takai N, Narahara H. Human endometrial and ovarian cancer cells: histone deacetylase inhibitors exhibit antiproliferative activity, potently induce cell cycle arrest, and stimulate apoptosis. Curr Med Chem 2007; 14:2548-2553.
14. Johannessen CU, Johannessen SI. Valproate: past, present, and future. CNS Drug Rev 2003; 9:199-216.
15. Cinatl JJr, Cinatl J, Driever PH, Kotchetkov R, Pouckova P, Kornhuber B, et al. Sodium valproate inhibits in vivo growth of human neuroblastoma cells. Anticancer Drugs 1997; 8:958-963.
16. Blaheta RA, Michaelis M, Driever PH, Cinatl JJr. Evolving anticancer drug valproic acid: insights into the mechanism and clinical studies. Med Res Rev 2005; 25:383-397.
17. Blaheta RA, Cinatl J Jr. Anti-tumor mechanisms of valproate: a novel role for an old drug. Med Res Rev 2002; 22:492-511.
18. Blaheta RA, Nau H, Michaelis M, Cinatl J Jr. Valproate and valproate-analogues: potent tools to fight against cancer. Curr Med Chem 2002; 9:1417-1433.
19. Beecken WD, Engl T, Ogbomo H, Relja B, Cinatl J, Bereiter-Hahn J, et al.  Valproic acid modulates NCAM polysialylation and polysialyltransferase mRNA expression in human tumor cells. Int Immunopharmacol 2005; 5:757-769.
20. Tsanou E, Peschos D, Batistatou A, Charalabopou-los A, Charalabopoulos K. The E-cadherin adhesion molecule and colorectal cancer. A global literature approach. Anticancer Res 2008; 28:3815-3826.
21. Berx G, Staes K, van Hengel J, Molemans F, Bussemakers MJ, van Bokhoven A, et al. Cloning and characterization of the human invasion suppressor gene E-cadherin (CDH1). Genomics 1995; 26:281-289.
22. Peinado H, Olmeda D, Cano A. Snail, Zeb and bHLH factors in tumour progression: an alliance against the epithelial phenotype? Nat Rev Cancer 2007; 7:415-428.
23. Simoes-Correia J, Figueiredo J, Oliveira C, van Hengel J, Seruca R, van Roy F, et al. Endoplasmic reticulum quality control: a new mechanism of E-cadherin regulation and its implication in cancer. Hum Mol Genet 2008; 17:3566-3576.
24. Oliveira C, Senz J, Kaurah P, Pinheiro H, Sanges R, Haegert A, et al. Germline CDH1 deletions in hereditary diffuse gastric cancer families. Hum Mol Genet 2009; 18:1545-1555.
25. Pinheiro H, Bordeira-Carrico R, Seixas S, Carvalho J, Senz J, Oliveira P, et al. Allele-specific CDH1 downregulation and hereditary diffuse gastric cancer. Hum Mol Genet 2010; 19:943-952.
26. Onder TT, Gupta PB, Mani SA, Yang J, Lander ES, Weinberg RA. Loss of E-cadherin promotes metastasis via multiple downstream transcriptional pathways. Cancer Res 2008; 68:3645-3654.
27. Karam R, Carvalho J, Bruno I, Graziadio C, Senz J, Huntsman D, et al. The NMD mRNA surveillance pathway downregulates aberrant E-cadherin transcripts in gastric cancer cells and in CDH1 mutation carriers. Oncogene 2008; 27:4255-4260.
28. Larue L, Bellacosa A. Epithelial-mesenchymal transition in development and cancer: role of phosphatidylinositol 39 kinase/AKT pathways. Oncogene 2005; 24:7443-7454.
29. Livak KJ, Schmittgen TD. Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C (T)) Method. Methods 2001; 25:402-408.
30. Martel C, Harper F, Cereghini S, Noe V, Mareel M, Cremisi C. Inactivation of retinoblastoma family proteins by SV40 T antigen results in creation of a hepatocyte growth factor/scatter factor autocrine loop associated with an epithelial-fibroblastoid conversion and invasiveness. Cell Growth Differ 1997; 8:165-178.
31. Caberg JH, Hubert PM, Begon DY, Herfs MF, Roncarati PJ, Boniver JJ, et al. Silencing of E7 oncogene restores functional E-cadherin expression in human papillomavirus 16-transformed keratino-cytes. Carcinogenesis 2008; 29:1441-1447.
32. Adhya D, Basu A. Epigenetic modulation of host: new insights into immune evasion by viruses. J Biosci 2010; 35:647-663.
33. Bestor TH. The DNA methyltransferases of mammals. Hum Mol Genet 2000;9:2395-2402.
34. Razin A. CpG methylation, chromatin structure and gene silencing-a three-way connection. EMBO J 1998; 17:4905-4908.
35. Fuks F,Burgers WA, Brehm A, Hughes-Davies L, Kouzarides T. DNA methyltransferase Dnmt1 associates with histone deacetylase activity. Nat Genet 2000; 24:88-91.
36. Fuks F, Burgers WA, Godin N, Kasai M, Kouzarides T. Dnmt3a binds deacetylases and is recruited by a sequence-specific repressor to silence transcription. EMBO J 2001; 20:2536-2544.
37. Fuks F, Hurd PJ, Deplus R, Kouzarides T. The DNA methyltransferases associate with HP1 and the SUV39H1 histone methyltransferase. Nucleic Acids Res 2003; 31:2305-2312.
38. Fuks F, Hurd PJ, Wolf D, Nan X, Bird AP, Kouzarides T. The methyl-CpG-binding protein MeCP2 links DNA methylation to histone methylation. J Biol Chem 2003; 278:4035-4040.
39. Burgers W, Fuks F, Kouzarides T. DNA methyl-transferases get connected to chromatin. Trends Genet 2002; 18:275-277.
40. Thiery JP. Epithelial-mesenchymal transitions in tumour progression. Nat Rev Cancer 2002; 2:442-454.
41. Gumbiner BM. Regulation of cadherin-mediated adhesion in morphogenesis. Nat Rev Mol Cell Biol 2005; 6:622-634.
42. Larue L, Bellacosa A. Epithelial-mesenchymal transition in development and cancer: role of phosphatidylinositol 39 kinase/AKT pathways. Oncogene 2005; 24:7443-7454.
43. Hagemann T, Bozanovic T, Hooper S, Ljubic A, Slettenaar VI, Wilson JL, et al. Molecular profiling of cervical cancer progression. Br J Cancer 2007; 6:321-328.
44. Yuecheng Y, Hongmei L, Xiaoyan X. Clinical evaluation of E-cadherin expression and its regulation mechanism in epithelial ovarian cancer. Clin Exp Metastasis 2006; 23:65-74.
45. Carico E, Atlante M, Bucci B, Nofroni I, Vecchione A. E-cadherin and alpha-catenin expression during tumor progression of cervical carcinoma. Gynecol Oncol 2001; 80:156-161.
46. D'Costa ZJ, Jolly C, Androphy EJ, Mercer A, Matthews CM, Hibma MH. Transcriptional repression of E-Cadherin by Human Papillomavirus Type 16 E6. PLoS One 2012; 7: ):e48954.
47. Laurson J, Khan S, Chung R, Cross K, Raj K. Epigenetic repression of E-cadherin by human papillomavirus 16 E7 protein. Carcinogenesis 2010; 31:918-926.
48. Annicotte JS, Iankova I, Miard S, Fritz V, Sarruf D, Abella A, et al. Peroxisome proliferator-activated receptor gamma regulates E-cadherin expression and inhibits growth and invasion of prostate cancer. Mol Cell Biol 2006; 26:7561-7574.
49. Shan Z, Feng-Nian R, Jie G, Ting Z. Effects of valproic acid on proliferation, apoptosis, angiogenesis and metastasis of ovarian cancer in vitro and in vivo. Asian Pac J Cancer Prev 2012; 13:3977-3982.
50. Feng D, Wu J, Tian Y, Zhou H, Zhou Y, Hu W, et al. Targeting of histone deacetylases to reactivate tumour suppressor genes and its therapeutic potential in a human cervical cancer xenograft model. PLoS One 2013; 19:8.
51. Moody TW, Switzer C, Santana-Flores W, Ridnour LA, Berna M, Thill M, et al. Dithiolethione modified valproate and diclofenac increase E-cadherin expression and decrease proliferation of non-small cell lung cancer cells. Lung Cancer 2010; 68:154-160.
52. Zhang L, Wang G, Wang L, Song C, Wang X, Kang J. Valproic acid inhibits prostate cancer cell migration by up-regulating E-cadherin expression. Pharmazie 2011; 66:614-618.
53. Iacopino F, Urbano R, Graziani G, Muzi A, Navarra P, Sica G. Valproic acid activity in androgen-sensitive and -insensitive human prostate cancer cells. Int J Oncol 2008; 32:1293-1303.
54. de la Cruz-Hernández E, Pérez-Cárdenas E, Contreras-Paredes A, Cantú D, Mohar A, Lizano M,                 et al.  The effects of DNA methylation and histone deacetylase inhibitors on human papillomavirus early gene expression in cervical cancer, an in vitro and clinical study. Virol J 2007; 4:18.
55. Chen J, Ghazawi FM, Bakkar W, Li Q. Valproic acid and butyrate induce apoptosis in human cancer cells through inhibition of gene expression of Akt/protein kinase B. Mol Cancer 2006;n 5:71.
56. Sami S, Höti N, Xu HM, Shen Z, Huang X. Valproic acid inhibits the growth of cervical cancer both in vitro and in vivo. J Biochem 2008; 144:357-362.
57. Tsai C, Leslie JS, Franko-Tobin LG, Prasnal MC, Yang T, Vienna Mackey L, et al. Valproic acid suppresses cervical cancer tumor progression possibly via activating Notch1 signaling and enhances receptor-targeted cancer chemotherapeutic via activating somatostatin receptor type II. Arch Gynecol Obstet 2013; 288:393-400.