Table 1.

Growth inhibition, induction of apoptosis, and cell cycle distribution in SW480 human colon cancer cells after treatment with garlic-derived and other organosulfur compounds

CompoundStructure
Growth inhibition*
Apoptosis
Cell cycle distribution
AllylDisulfideIC50 (μmol/L)Sub-G1%G1%S%G2-M%
Control5571825
SAMC++15054201664
SAC+§2561628
DADS++5636382438
DAS+§3542026
Cysteine§6611425
Cystine+§5621820
GSH§5631621
GSSG+§5611920
Propyl-glu§3542323
Benzyl-cys1 Benzyl ringSulfide§6542125
Trityl-cys3 Benzyl ringSulfide0.928381745
  • Abbreviations: GSH, reduced glutathione; GSSG, oxidized glutathione; benzyl-cys, benzyl-S-cysteine; propyl-glu, S-propylglutathione.

  • * Cells were treated with 50 to 250 μmol/L of each compound for 48 hours. Cell numbers were then determined by cell counting and the IC50 values were determined from cell survival curves.

  • Cells were treated with each compound for 48 hours and then stained with propidium iodide and analyzed by flow cytometry for apoptosis, assessed by the sub-G1 population. SAMC, DADS, and trityl-cys were tested at twice their IC50 concentration; other compounds were tested at 300 μmol/L.

  • Cells were treated with each compound for 24 hours and then stained with propidium iodide and analyzed by flow cytometry for cell cycle distribution. SAMC, DADS, and trityl-cys were tested at twice their IC50 concentration and other compounds were tested at 300 μmol/L.

  • § No effects on growth inhibition when tested at up to 250 μmol/L.