PMID- 28548062
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20200930
IS  - 2227-9059 (Print)
IS  - 2227-9059 (Electronic)
IS  - 2227-9059 (Linking)
VI  - 2
IP  - 1
DP  - 2014 Mar 5
TI  - Gulonolactone Addition to Human Hepatocellular Carcinoma Cells with Gene Transfer 
      of Gulonolactone Oxidase Restores Ascorbate Biosynthesis and Reduces Hypoxia 
      Inducible Factor 1.
PG  - 98-109
LID - 10.3390/biomedicines2010098 [doi]
AB  - Humans are unable to synthesise ascorbate (Vitamin C) due to the lack of a 
      functional gulonolactone oxidase (Gulo), the enzyme that catalyses the final step 
      in the biosynthesis pathway. Ascorbate is a vital micronutrient required for many 
      biological functions, including as a cofactor for metalloenzymes that regulate 
      the transcription factor hypoxia-inducible factor-1 (HIF-1), which governs cell 
      survival under hypoxia. In most animals, ascorbate is made in liver cells. This 
      study aimed to restore ascorbate synthesis to human hepatocellular carcinoma 
      HepG2 cells and determine the effect of internally produced ascorbate on HIF-1 
      activation. HepG2 cells were gene-modified with a plasmid encoding the mouse Gulo 
      cDNA, tested for genomic incorporation by PCR and ascorbate synthesis by high 
      performance liquid chromatography. Levels of HIF-1 protein were measured using 
      Western blotting. Gulo-modified HepG2 cells showed increased adherence compared 
      to control HepG2 cells. A PCR-positive clone synthesised ascorbate when the Gulo 
      substrate, l-gulono-1,4-lactone, was supplied. Intracellular ascorbate 
      concentrations reached 5% of saturation levels (6 nmol/10(6) cells). Addition of 
      ascorbate or gulonolactone reduced HIF-1 accumulation in the Gulo clone, but also 
      in parental HepG2 cells. Our data confirm the requirement for a number of factors 
      in addition to Gulo in the ascorbate biosynthesis pathway in human cells.
FAU - Flett, Teresa
AU  - Flett T
AD  - Mackenzie Cancer Research Group, Department of Pathology, University of Otago, PO 
      Box 4345, Christchurch 8140, New Zealand. flete688@student.otago.ac.nz.
FAU - Campbell, Elizabeth J
AU  - Campbell EJ
AD  - Mackenzie Cancer Research Group, Department of Pathology, University of Otago, PO 
      Box 4345, Christchurch 8140, New Zealand. elizabeth.campbell@otago.ac.nz.
FAU - Phillips, Elisabeth
AU  - Phillips E
AD  - Mackenzie Cancer Research Group, Department of Pathology, University of Otago, PO 
      Box 4345, Christchurch 8140, New Zealand. elisabeth.phillips@otago.ac.nz.
FAU - Vissers, Margreet C M
AU  - Vissers MCM
AD  - Centre for Free Radical Research, Department of Pathology, University of Otago, 
      PO Box 4345, Christchurch 8140, New Zealand. margreet.vissers@otago.ac.nz.
FAU - Dachs, Gabi U
AU  - Dachs GU
AD  - Mackenzie Cancer Research Group, Department of Pathology, University of Otago, PO 
      Box 4345, Christchurch 8140, New Zealand. gabi.dachs@otago.ac.nz.
LA  - eng
PT  - Journal Article
DEP - 20140305
PL  - Switzerland
TA  - Biomedicines
JT  - Biomedicines
JID - 101691304
PMC - PMC5423483
OTO - NOTNLM
OT  - HIF-1
OT  - gene therapy
OT  - vitamin C
COIS- The authors declare no conflict of interest.
EDAT- 2014/03/05 00:00
MHDA- 2014/03/05 00:01
PMCR- 2014/03/05
CRDT- 2017/05/27 06:00
PHST- 2013/12/20 00:00 [received]
PHST- 2014/02/26 00:00 [revised]
PHST- 2014/02/26 00:00 [accepted]
PHST- 2017/05/27 06:00 [entrez]
PHST- 2014/03/05 00:00 [pubmed]
PHST- 2014/03/05 00:01 [medline]
PHST- 2014/03/05 00:00 [pmc-release]
AID - biomedicines2010098 [pii]
AID - biomedicines-02-00098 [pii]
AID - 10.3390/biomedicines2010098 [doi]
PST - epublish
SO  - Biomedicines. 2014 Mar 5;2(1):98-109. doi: 10.3390/biomedicines2010098.