Why could histone be co-immunoprecipitated with keratin 18 in human hepatocellular carcinoma ?

1. Why could histone be co-immunoprecipitated with keratin 18 in human hepatocellular carcinoma? HO, CHIN-CHIN

2. Background-1

4. Human hepatocytes have a very simple cytokeratin (CK) composition and express only one CK pair : CK 8 (type II, 52 kD) andCK 18 (type I, 45 kD). • Van Eken P et al. Human Pathol. 1988;19(5):562-568

5. Methods 1.SDS-PAGE 2.Western blot (Immunoblot) 3.Immunoprecipitation (IPP)

6. Results

8. CK18-IPP 45 kD 14 kD HCC CK

9. Conclusions 1. The cytokeratin molecule is modulated in hepatoma. 2. The hepatoma cytokeratin (HCC CK) is generated from the hepatocyte cytokeratin.

10. Although the HCC CK was derived from CK18 in HCC, however its antigenicity had been changed by the Western blotting.

11. CK18-IPP 45 kD 14 kD HCC CK

12. Background-2

14. CK18-IPP 45 kD 14 kD HCC CK

15. By using reverse-phase HPLC to analyze the chymotrypticdigest of the HCC CKfraction, twenty-one peptides were purified and sequenced.

16. The sequences of N-terminalof these chymotrytic peptidesofHCC CK were matched with those of the N-terminal residues of human histone.

17. Methods and Results

18. T CK18-IPP

19. Conclusion HCC CKs are altered histones in hepatoma.

20. AIM: Why could histone be co-immunoprecipitated with keratin 18 in human hepatocellular carcinoma

21. Methods and Results

22. HCC Normal liver Nuclear isolation extraction CK or histoneImmunoprecipitation Liu’s stain Westen blot assay Whole cells &

23. Tissue Extraction CK18-IPP A CK18 N T2 T3 T1 B Histone Hepatocellular carcinoma Western blot of Western blot of

24. Tissue Extraction Histone-IPP A CK18 B T1 T2 T3 N Histone Hepatocellular carcinoma Western blot of Western blot of

25. histones

26. HCC Normal liver Nuclear isolation extraction CK or histoneImmunoprecipitation Liu’s stain Western blot assay Whole cells &

27. Whole cells of Normal liver tissues;Nuclear isolation of Normal liver tissues A C B D Liu’s stain Whole cells of HCC Nuclear isolation of HCC

28. Pellets N T N T CK18-IPP Supernatants Supernatants Pellets N T N T Western blot of Pellets Supernatants N T N T Western blot of

29. Conclusion Histone is co-immunoprecipitated with keratin 18 in human hepatocellular carcinoma.

30. Speculation The histones were exposed from the nucleiduring the process of extractionbecause the nuclei of hepatocellular carcinoma were more unstable and fragile.

31. Thank You for your attention !