PGPIPN induced tumor growth inhibition associated with cell apoptosis.

<p>(A) TUNEL assay shows the apoptotic tumor cells in PGPIPN-treated samples extracted from xenograft mice (×400). (B) Apoptotic index was calculated as following formula: AI = (the number apoptotic cell/the total number of cells )× 100% (mean ± <i>SD</i>,n = 6), **<i>P</i><0.01. (C) DNA fragment assay shows that PGPIPN induced tumor DNA degradation in high dose PGPIPN group (high) and low dose PGPIPN group (low), but not in normal saline group (NS). (D) Protein levels of BCL2 and Bax were examined by western blot in tumor samples extracted from xenografted mice (top panel). The band intensities were measured by Imaging J software and summarized (bottom panel). The data are from 6 tumors of each group, *<i>P</i><0.05, **<i>P</i><0.01 compared with NS group.