Hamigeran G Does Not Affect Golgi Structure or Function in HEK293 Cells

The hamigerans are diterpenoid secondary metabolites isolated from the New Zealand marine sponge Hamigera tarangaensis. Of all the hamigerans that have been isolated and characterised at Victoria University of Wellington, hamigeran G showed the most potent anti-proliferative activity against a mammalian cancer cell line. We previously reported that it might be targeting the Golgi network of cells based on a chemical genomic screen on yeast (Saccharomyces cerevisiae). Here, we investigated the effects of hamigeran G on the Golgi network of mammalian cells and showed that it did not have a significant effect on Golgi apparatus morphology or Golgi network functions such as protein secretion and endocytosis. Results of this study, therefore, conclude that the Golgi network is unlikely to be the primary target of hamigeran G's anti-proliferative activity. Further work is needed to fully elucidate the mechanism of action and target(s) of hamigeran G.