Both cell lines experience elevation of apoptosis following application of sorafenib in a dose dependent manner, as evident from the AnnV/7AAD results. However, while TTFields greatly elevate apoptosis in HepG2 cells, they have a low effect on apoptosis levels in the Huh-7D12 cells, seen both in Figure 1d and in Figure 3c. As was explained in the discussion, this difference between the cell lines may be attributed to the different p53 status, wild type in HepG2 and mutated in Huh-7D12, as there are previous indications of lower TTFields-induced apoptosis in cell lines with mutated p53. As suggested by the reviewer, in order to back up the AnnV/7AAD results we added WB for cleaved PARP, as described in response 3.
Point 7: The authors claim that cytotoxicity was measured “by cell counting using iCyt EC800 (Sony Biotechnology) 123 flow cytometer, and expressed as a percentage relative to the control.” Does this imply that they counted the live cells and plotted the final data as percentage of untreated controls (as figure 1 suggests).