Different response to oleic acid administration in hepatocellular carcinoma vs non tumorigenic hepatocyte cell lines

Thanks to the presence of high levels of monounsaturated fatty acids, extra virgin olive oil is beneficial for health as it is associated with protection against liver steatosis, some types of cancer and cardiovascular diseases. Here we study different responses between hepatocarcinoma cell lines (Hep3B and Huh7.5) vs a healthy hepatocyte control (THLE-2) following the treatment with oleic acid (OA), in particular we have observed a dose-dependent response (50-300 M). First of all, we observed a different neutral lipid accumulation between the hepatocarcinoma cells and the healthy control. Moreover, we have found a differential viability rate; a reduction of hepatocarcinoma cell lines at 300 M OA dosage but unchanged vitality in healthy hepatocytes through Alamar Blue staining. Furthermore, we evaluated the apoptotic rate by western blot, we have found that the levels of cleaved PARP appear differently modulated in the hepatocarcinoma cell lines following the treatment with OA. We also found that, while hepatocarcinoma cell lines respond to dose-dependent OA treatment with autophagic flux reduction, healthy controls do not significantly modulate their autophagic flux, thus hypothesizing a protective role of autophagy in hepatocytes cell vitality. In order to better investigate the different autophagic response of Huh7.5 and Hep3B carcinoma cells as compared to healthy THLE-2 cells we analyzed the levels of perilipin-2 since it has been previously shown to have a crucial role in liver autophagy regulation. We interestingly found that in Huh7.5 and Hep3B carcinoma cells dose-dependent OA (50-300 M) treatment is associated to increasing perilipin-2 levels. Such results are in agreement with previous studies showing and inverse relationship between perilipin-2 and autophagy levels. Further experiments are ongoing to manipulate autophagy in order to investigate at molecular level the beneficial effects of OA in counteracting hepatocarcinoma.