Consistent with their non-tumorigenic feature, the imPAC2 cells failed to form any subcutaneous masses in the absence of PPCNg scaffold, while the imPAC2-KRAS/TP53R273H cells formed obvious masses without PPCNg scaffold (Fig. 7A-a), and exhibited a highly proliferative feature histologically (Fig. 7A-b), suggesting that concurrent overexpression of oncogenic KRAS and mutant TP53 may be sufficient to render the imPAC2 cells tumor-like phenotype. Here, KRAS is linked to neoplasm.