Epigenetic targets in hepatocellular carcinoma cells: identification of chaperone protein complexes with histone deacetylases.
OBJECTIVE
The study was designed to find out the protein complex(s) associated with HDAC3 in liver cancer using a modified form of affinity purification coupled with a mass spectrometry technique in HepG2 cells. The organ-specific requirement for HDAC1 and HDAC3 during liver formation in zebrafish and their altered expression in liver cancer tissues indicates they are indispensible for hepato-organogenesis and hepatocarcinogenesis. However, how they exert their function is unknown.


METHODS
HepG2 cells were transfected with either mock or construct-containing HDAC3 using a C-terminal strepIII-HA tag as bait. The bait proteins were purified by double affinity columns and were analyzed on a Thermo LTQ Orbitrap™ (Thermo Scientific, MA, USA) chromatography system.


RESULTS
Affinity purification coupled with mass spectrometry resulted in the identification of 24 putative binders of HDAC3 in HepG2 cells. The majority (83%) of these are novel interactions are reported for the first time in this study.


CONCLUSIONS
This is the first study reporting the affinity purification and identification of protein complexes with two closely related proteins in one cell line. The novel HDAC1 and HDAC3 complexes identified in HepG2 cells could serve as a platform for the design of future therapeutic medicine for the treatment of liver cancer.
Bioproducts Research Chair, College of Science, Department of Zoology, King Saud University, Riyadh 11451, Kingdom of Saudi Arabia.
Muhammad
M
Farooq
Mohammad A M
MA
Wadaan
D000818:Animals; D006528:Carcinoma, Hepatocellular; D002460:Cell Line; D006655:Histone Deacetylases / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms
D006655:Histone Deacetylases