Someone said HL-7702 is one kind of normal liver cell can be cultured, but others said the background or origion of HL-7702 is not clear. I don't know which one is right.
I've worked extensively with HepG2 cells, they're not quite normal (none of the cell lines will be - to grow as cell lines, they will be abnormal in some way!) However, their background is quite well defined:
you can get them to behave very liver cell like by using a special medium (see attached file).
Perhaps you could tell us a little bit more about what you want the cells for, then we could maybe advise on appropriate ones?
It is quite a good idea to use two cell lines for basic research stuff, to exclude possibility that your interesting mechanism of action isn't an artefact of the cell line and it's particular mutations...