Skip to content
Licensed Unlicensed Requires Authentication Published by De Gruyter March 1, 2013

Betaine homocysteine methyltransferase (BHMT)-dependent remethylation pathway in human healthy and tumoral liver

  • Hélène Pellanda EMAIL logo

Abstract

Carcinogenesis is a multi-step and multifactorial process. It includes genetic, epigenetic, nutritional and environmental factors, which are closely interconnected. Human hepatocellular carcinoma (HCC) is among the most frequent and lethal cancers. Imbalance in the S-adenosylmethionine (SAM) concentration, the main methyl group donor, strongly influences the development of HCC. Key enzymes of carbon metabolism are greatly reduced in patients with cirrhosis and HCC. These alterations play a role in genetic instability and epigenetic modifications (DNA methylation, and histone modifications), however, the molecular underlying mechanisms are still poorly understood. We aimed to investigate betaine homocysteine methyltransferase (BHMT) expression in HepG2 cells and human hepatocarcinoma tissues. Tumor and surrounding healthy tissue were compared. HepG2 cells and tumor samples showed a strong decrease in BHMT transcripts resulting from the transcription of a splicing variant that contained a frameshift mutation generating a premature termination codon and gene loss of function. This splicing variant, not detected in normal adult and fetal liver, cannot be explained by any mechanism involving the known splicing consensus sequences. BHMT activity was abolished in HepG2 cells and protein expression was detected neither in HepG2 cells nor in five of the six tumor samples investigated. Further investigation is needed to elucidate whether this abnormal BHMT transcription is part of cause or consequence of liver carcinogenesis.


Corresponding author: Hélène Pellanda, INSERM U 954, Faculté de Médecine – BP 184, 54511 Vandoeuvre les Nancy, France, Phone: +333 83 683292, Fax: +333 83 683279

Acknowledgments: Financial support to complete this work was provided by the Ligue Contre le Cancer (Grant project CIRCE), France.

Conflict of interest statement

Authors’ conflict of interest disclosure: The authors stated that there are no conflicts of interest regarding the publication of this article.

Research funding: None declared.

Employment or leadership: None declared.

Honorarium: None declared.

References

1. Ueland PM. Choline and betaine in health and disease. J Inherit Metab Dis 2011;34:3–15.10.1007/s10545-010-9088-4Search in Google Scholar

2. Michel V, Yuan Z, Ramsubir S, Bakovic M. Choline transport for phospholipid synthesis. Exp Biol Med (Maywood) 2006;231:490–504.10.1177/153537020623100503Search in Google Scholar

3. Zeisel SH. Dietary choline: biochemistry, physiology, and pharmacology. Annu Rev Nutr 1981;1:95–121.10.1146/annurev.nu.01.070181.000523Search in Google Scholar

4. Porter RK. Mammalian mitochondrial inner membrane cationic and neutral amino acid carriers. Biochim Biophys Acta 2000;1459:356–62.10.1016/S0005-2728(00)00172-9Search in Google Scholar

5. Lever M, Slow S. The clinical significance of betaine, an osmolyte with a key role in methyl group metabolism. Clin Biochem 2010;43:732–44.10.1016/j.clinbiochem.2010.03.009Search in Google Scholar PubMed

6. Delgado-Reyes CV, Wallig MA, Garrow TA. Immunohistochemical detection of betaine-homocysteine S-methyltransferase in human, pig, and rat liver and kidney. Arch Biochem Biophys 2001;393:184–6.10.1006/abbi.2001.2474Search in Google Scholar PubMed

7. Garcia-Tevijano ER, Berasain C, Rodríguez JA, Corrales FJ, Arias R, Martín-Duce A, et al. Hyperhomocysteinemia in liver cirrhosis: mechanisms and role in vascular and hepatic fibrosis. Hypertension 2001;38:1217–21.10.1161/hy1101.099499Search in Google Scholar PubMed

8. Mato JM, Corrales FJ, Lu SC, Avila MA. S-Adenosylmethionine: a control switch that regulates liver function. Faseb J 2002;16:15–26.10.1096/fj.01-0401revSearch in Google Scholar PubMed

9. Lu SC, Alvarez L, Huang ZZ, Chen L, An W, Corrales FJ, et al. Methionine adenosyltransferase 1A knockout mice are predisposed to liver injury and exhibit increased expression of genes involved in proliferation. Proc Natl Acad Sci USA 2001;98:5560–5.10.1073/pnas.091016398Search in Google Scholar PubMed PubMed Central

10. Mato JM, Lu SC. Role of S-adenosyl-L-methionine in liver health and injury. Hepatology 2007;45:1306–12.10.1002/hep.21650Search in Google Scholar PubMed

11. Ventura P, Rosa MC, Abbati G, Marchini S, Grandone E, Vergura P, et al. Hyperhomocysteinaemia in chronic liver diseases: role of disease stage, vitamin status and methylenetetrahydrofolate reductase genetics. Liver Int 2005;25:49–56.10.1111/j.1478-3231.2005.01042.xSearch in Google Scholar

12. Buchman AL, Dubin MD, Moukarzel AA, Jenden DJ, Roch M, Rice KM, et al. Choline deficiency: a cause of hepatic steatosis during parenteral nutrition that can be reversed with intravenous choline supplementation. Hepatology 1995;22:1399–403.Search in Google Scholar

13. Zeisel SH, Da Costa KA, Franklin PD, Alexander EA, Lamont JT, Sheard NF, et al. Choline, an essential nutrient for humans. Faseb J 1991;5:2093–8.10.1096/fasebj.5.7.2010061Search in Google Scholar

14. Fischer LM, DaCosta KA, Kwock L, Stewart PW, Lu TS, Stabler SP, et al. Sex and menopausal status influence human dietary requirements for the nutrient choline. Am J Clin Nutr 2007;85:1275–85.10.1093/ajcn/85.5.1275Search in Google Scholar

15. Vance DE, Li Z, Jacobs RL. Hepatic phosphatidylethanolamine N-methyltransferase, unexpected roles in animal biochemistry and physiology. J Biol Chem 2007;282:33237–41.10.1074/jbc.R700028200Search in Google Scholar

16. Kharbanda KK, Mailliard ME, Baldwin CR, Beckenhauer HC, Sorrell MF, Tuma DJ. Betaine attenuates alcoholic steatosis by restoring phosphatidylcholine generation via the phosphatidylethanolamine methyltransferase pathway. J Hepatol 2007;46:314–21.10.1016/j.jhep.2006.08.024Search in Google Scholar

17. Copeland DH, Salmon WD. The occurrence of neoplasms in the liver, lungs, and other tissues of rats as a result of prolonged choline deficiency. Am J Pathol 1646;22:1059–79.Search in Google Scholar

18. Salmon WD, Copeland DH. Liver carcinoma and related lesions in chronic choline deficiency. Ann N Y Acad Sci 1954;57:665–77.Search in Google Scholar

19. Ghoshal AK, Farber E. The induction of liver cancer by dietary deficiency of choline and methionine without added carcinogens. Carcinogenesis 1984;5:1367–70.10.1093/carcin/5.10.1367Search in Google Scholar

20. Yokoyama S, Sells MA, Reddy TV, Lombardi B. Hepatocarcinogenic and promoting action of a choline-devoid diet in the rat. Cancer Res 1985;45:2834–42.Search in Google Scholar

21. Laird PW, Jaenisch R. The role of DNA methylation in cancer genetic and epigenetics. Annu Rev Genet 1996;30:441–64.10.1146/annurev.genet.30.1.441Search in Google Scholar

22. Wainfan E, Dizik M, Stender M, Christman JK. Rapid appearance of hypomethylated DNA in livers of rats fed cancer-promoting, methyl-deficient diets. Cancer Res 1989;49:4094–7.Search in Google Scholar

23. Avila MA, Berasain C, Torres L, Martín-Duce A, Corrales FJ, Yang H, et al. Reduced mRNA abundance of the main enzymes involved in methionine metabolism in human liver cirrhosis and hepatocellular carcinoma. J Hepatol 2000;33:907–14.10.1016/S0168-8278(00)80122-1Search in Google Scholar

24. Frau M, Tomasi ML, Simile MM, Demartis MI, Salis F, Latte G, et al. Role of transcriptional and post-transcriptional regulation of methionine adenosyltransferases in liver cancer progression. Hepatology 2012;56:165–75.10.1002/hep.25643Search in Google Scholar PubMed

25. Duce AM, Ortiz P, Cabrero C, Mato JM. S-adenosyl-L-methionine synthetase and phospholipid methyltransferase are inhibited in human cirrhosis. Hepatology 1988;8:65–8.10.1002/hep.1840080113Search in Google Scholar PubMed

26. Teng YW, Mehedint MG, Garrow TA, Zeisel SH. Deletion of betaine-homocysteine S-methyltransferase in mice perturbs choline and 1-carbon metabolism, resulting in fatty liver and hepatocellular carcinomas. J Biol Chem 2011;286:36258–67.10.1074/jbc.M111.265348Search in Google Scholar

27. Pellanda H, Namour F, Fofou-Caillierez M, Bressenot A, Alberto JM, Chery C, et al. A splicing variant leads to complete loss of function of Betaine-homocysteine methyltransferase (BHMT) gene in hepatocellular carcinoma. Int J Biochem Cell Biol 2012;44:385–92.10.1016/j.biocel.2011.11.014Search in Google Scholar

28. Liang CR, Leow CK, Neo JC, Tan GS, Lo SL, Lim JW, et al. Proteome analysis of human hepatocellular carcinoma tissues by two-dimensional difference gel electrophoresis and mass spectrometry. Proteomics 2005;5:2258–71.10.1002/pmic.200401256Search in Google Scholar

29. Sun W, Xing B, Sun Y, Du X, Lu M, Hao C, et al. Proteome analysis of hepatocellular carcinoma by two-dimensional difference gel electrophoresis: novel protein markers in hepatocellular carcinoma tissues. Mol Cell Proteomics 2007;6:1798–808.10.1074/mcp.M600449-MCP200Search in Google Scholar

30. Ichikawa A, Ohashi Y, Terada S, Natsuka S, Ikura K. In vitro modification of betaine-homocysteine S-methyltransferase by tissue-type transglutaminase. Int J Biochem Cell Biol 2004;36:1981–92.10.1016/j.biocel.2004.02.014Search in Google Scholar

31. Feng Q, Kalari K, Fridley BL, Jenkins G, Ji Y, Abo R, et al. Betaine-homocysteine methyltransferase: human liver genotype-phenotype correlation. Mol Genet Metab 2011;102:126–33.10.1016/j.ymgme.2010.10.010Search in Google Scholar

32. Green RE, Lewis BP, Hillman RT, Blanchette M, Lareau LF, Garnett AT, et al. Widespread predicted nonsense-mediated mRNA decay of alternatively-spliced transcripts of human normal and disease genes. Bioinformatics 2003;19(Suppl 1):i118–21.10.1093/bioinformatics/btg1015Search in Google Scholar

33. Ou X, Yang H, Ramani K, Ara AI, Chen H, Mato JM, et al. Inhibition of human betaine-homocysteine methyltransferase expression by S-adenosylmethionine and methylthioadenosine. Biochem J 2007;401:87–96.10.1042/BJ20061119Search in Google Scholar

34. Ji C, Shinohara M, Kuhlenkamp J, Chan C, Kaplowitz N. Mechanisms of protection by the betaine-homocysteine methyltransferase/betaine system in HepG2 cells and primary mouse hepatocytes. Hepatology 2007;46:1586–96.10.1002/hep.21854Search in Google Scholar

40. Finkelstein JD, Martin JJ. Methionine metabolism in mammals. Distribution of homocysteine between competing pathways. J Biol Chem 1984;259:9508–13.10.1016/S0021-9258(17)42728-1Search in Google Scholar

35. Halpern BC, Clark BR, Hardy DN, Halpern RM, Smith RA. The effect of replacement of methionine by homocystine on survival of malignant and normal adult mammalian cells in culture. Proc Natl Acad Sci USA 1974;71:1133–6.10.1073/pnas.71.4.1133Search in Google Scholar

36. Mecham JO, Rowitch D, Wallace CD, Stern PH, Hoffman RM. The metabolic defect of methionine dependence occurs frequently in human tumor cell lines. Biochem Biophys Res Commun 1993;117:429–34.10.1016/0006-291X(83)91218-4Search in Google Scholar

37. Ashe H, Clark BR, Chu F, Hardy DN, Halpern BC, Halpern RM, et al. N5-methyltetrahydrofolate: homocysteine methyltransferase activity in extracts from normal, malignant and embryonic tissue culture cells. Biochem Biophys Res Commun 1974;57:417–25.10.1016/0006-291X(74)90947-4Search in Google Scholar

38. Chango A, Nour AA, Bousserouel S, Eveillard D, Anton PM, Guéant JL. Time course gene expression in the one-carbon metabolism network using HepG2 cell line grown in folate-deficient medium. J Nutr Biochem 2009;20: 312–20.10.1016/j.jnutbio.2008.04.004Search in Google Scholar

39. Marguerite V, Beri-Dexheimer M, Ortiou S, Guéant JL, Merten M. Cobalamin potentiates vinblastine cytotoxicity through downregulation of mdr-1 gene expression in HepG2 cells. Cell Physiol Biochem 2007;20:967–76.10.1159/000110457Search in Google Scholar

41. Mato JM, Martinez-Chantar ML, Lu SC. Methionine metabolism and liver disease. Annu Rev Nutr 2008;28:273–93.10.1146/annurev.nutr.28.061807.155438Search in Google Scholar

42. Cellarier E, Durando X, Vasson MP, Farges MC, Demiden A, Maurizis JC, et al. Methionine dependency and cancer treatment. Cancer Treat Rev 2003;29:489–99.10.1016/S0305-7372(03)00118-XSearch in Google Scholar

43. Durando X, Thivat E, Gimbergues P, Cellarier E, Abrial C, Dib M, et al. Methionine dependency of cancer cells: a new therapeutic approach? Bull Cancer 2008;95:69–76.Search in Google Scholar

44. Battaglia-Hsu SF, Akchiche N, Noel N, Alberto JM, Jeannesson E, Orozco-Barrios CE, et al. Vitamin B12 deficiency reduces proliferation and promotes differentiation of neuroblastoma cells and up-regulates PP2A, proNGF, and TACE. Proc Natl Acad Sci USA 2009;106:21930–5.10.1073/pnas.0811794106Search in Google Scholar PubMed PubMed Central

45. Lai SC, Nakayama Y, Sequeira JM, Quadros EV. Down-regulation of transcobalamin receptor TCbIR/CD320 by siRNA inhibits cobalamin uptake and proliferation of cells in culture. Exp Cell Res 2011;317:1603–7.10.1016/j.yexcr.2011.02.016Search in Google Scholar PubMed PubMed Central

Received: 2012-10-11
Accepted: 2012-11-30
Published Online: 2013-03-01
Published in Print: 2013-03-01

©2013 by Walter de Gruyter Berlin Boston

Downloaded on 26.2.2024 from https://www.degruyter.com/document/doi/10.1515/cclm-2012-0689/html
Scroll to top button