The expression levels of SOX2 in tumor and tumor-free tissue in the lungs of PLGA-PEI-si-m/hVDAC1-B- and PLGA-PEI-si-NT-treated mice using specific antibodies showed that SOX2 levels were higher in the tumor-free than in the tumor lung tissue in both the PLGA-PEI-si-m/hVDAC1-B- and PLGA-PEI-si-NT-treated mice (Figure 5A). Here, SOX2 is linked to neoplasm.