SLC6A14 and cancer: The beneficial consequences of increased expression and activity of these transporters relate to cancer-cell survival and proliferation in multiple ways: acquisition of essential amino acids (SLC7A5 and SLC6A14), glutamine (SLC7A5, SLC1A5, SLC6A14 and SLC38A5), methionine (SLC7A5, SLC6A14 and SLC38A5), serine (SLC1A5, SLC7A5, SLC6A14, SLC38A5, and SLC43A2), and cystine (SLC7A11).