Furthermore, although an in vitro tumor formation assay in Patu-89088T and PANC-1 cells confirmed that tumorigenesis was enhanced in COX7A2L-deficient cells cultured in glutamine-containing medium (Figure 7H-I) in comparison with that in glutamine-depleted medium (Figure 7J), an in vivo tumorigenesis assay, which generated nutrient-poor microenvironment during tumor growth, showed that COX7A2L expression promoted the growth of PDAC cells when compared with COX7A2L KD (Figure S6A-E). Here, COX7A2L is linked to neoplasm.