Intermediary metabolite profiling showed a similar decrease in utilization of glutamine and a significant reduction in key TCA metabolites such as α-keto-Glutarate, succinate and fumarate in NF1 associated cell lines (MPNST and ST8814) compared to wild-type NF1 cell lines (LS141 and STS26T) as well as in MPNST tumor xenograft samples in vivo. The gene discussed is NF1; the disease is neoplasm.