GLUL and lung cancer: A concerted effort was made to circumvent toxicity issues by blocking glutamine availability to cancer cells either through inhibiting its uptake using GPNA(γ-L-glutamyl-p-nitroanilide) in lung cancer [60], or preventing its synthesis by inhibiting glutamine synthase using inhibitors such as BPTES(Bis-2-(5-phenylacetamido-1, 2, 4-thiadiazol-2-yl)ethyl sulfide) [61], compound 968 [62] and L-asparaginase [63].