title: Early evaluation for treatment efficacy of 5-fluorouracil and hyperthermia on HCT-116 colon cancer cells by fluorine-18-fluorodeoxyglucose uptake.
abstract: BACKGROUND
  Fluorine-18-fluorodeoxyglucose ((18)F-FDG) positron emission tomography imaging can be used to assess the treatment efficacy of chemotherapy and prognosis. The aim of this study was to determine the uptake rate of (18)F-FDG in colon cancer HCT-116 cells, and to evaluate the treatment efficacy of chemotherapy, hyperthermia and thermo-chemotherapy through the uptake inhibition rate of (18)F-FDG.
  
  
  METHODS
  The uptake rate of (18)F-FDG in HCT-116 cells was determined at various experimental conditions. The inhibition rate of cell growth, uptake rate of (18)F-FDG and uptake inhibition rate of (18)F-FDG in HCT-116 cells treated with 5-fluorouracil (5-FU) at various concentrations were determined. In HCT-116 cells subjected to chemotherapy (5-FU, 100 µg/ml), hyperthermia (43°C, 40 minutes) and thermo-chemotherapy for 24 hours, the inhibition rate of cell growth and uptake inhibition rate of (18)F-FDG were determined; early apoptosis, the morphology and ultrastructure of HCT-116 cells were examined; and the contents of glucose and lactate dehydrogenase (LDH) in the cell culture medium of HCT-116 cells were determined. One-way analysis of variance (ANOVA) and correlation analyses were conducted by using SPSS 16.0 software.
  
  
  RESULTS
  The uptake rate of (18)F-FDG in HCT-116 cells was (44.25 ± 2.19)%. Under the condition of adding 5-FU at various concentrations for 24 hours, the uptake rate of (18)F-FDG was negatively correlated with 5-FU dosage (r = -0.879, P < 0.01); the inhibition rate of cell growth revealed a positive correlation with the uptake inhibition rate of (18)F-FDG (r = 0.831, P < 0.01). In HCT-116 cells subjected to hyperthermia, chemotherapy, and thermo-chemotherapy for 24 hours, the uptake inhibition rates of (18)F-FDG were (12.94 ± 2.80)%, (28.25 ± 4.59)%, and (21.60 ± 3.68)%, respectively. The early apoptotic rates of HCT-116 cells were (9.80 ± 0.16)%, (19.80 ± 2.40)%, and (15.70 ± 1.80)%, respectively. Moreover, the contents of glucose and LDH in cell culture medium of HCT-116 cells after treatments were higher than those before treatment.
  
  
  CONCLUSIONS
  The uptake inhibition rate of (18)F-FDG can be used for early evaluation of hyperthermia and 5-FU treatment efficacy on cancer cells although hyperthermia (43°C, 40 minutes) does not reveal the synergistic effect on 5-FU at the low dosage.
authors.affiliation: Department of Oncology, the First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Zhen-xin
authors.initials: ZX
authors.lastname: Wang
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.forename: Sheng-ming
authors.initials: SM
authors.lastname: Deng
authors.forename: Shao-ji
authors.initials: SJ
authors.lastname: Chen
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D003110:Colonic Neoplasms / Q000378:metabolism*; D005334:Fever / Q000378:metabolism*; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism*; D005472:Fluorouracil / Q000494:pharmacology*; D045325:HCT116 Cells; D006801:Humans; D046529:Microscopy, Electron, Transmission
chemical_list: D019788:Fluorodeoxyglucose F18; D005472:Fluorouracil