A Tumor-Specific Tissue-Penetrating Peptide Enhances the Efficacy of Chemotherapy Drugs in Gastric Cancer

PURPOSE: C-end rule (CendR) peptides are found to enhance the penetration of chemotherapeutic agents into tumor cells, while GX1 is a peptide that homes to gastric cancer (GC) vasculature. This study aimed to synthesize a novel peptide GX1-RPAKPAR (GXC) and to explore the effect of GXC on sensitizing GC cells to chemotherapeutic agents. MATERIALS AND METHODS: Intracellular Adriamycin concentration analysis was applied to conform whether GXC peptide increases the penetration of chemotherapeutic agents into GC cells in vitro. The effect of GXC peptide on sensitizing GC cells to chemotherapeutics was validated by apoptosis assay and in vitro/vivo drug sensitivity assay. The specificity of GXC to GC tissue was validated by ex vivo fluorescence imaging. RESULTS: In vitro, administration of GXC significantly increased Adriamycin concentrations inside SGC-7901 cells, and enhanced the efficacy of chemotherapeutic agents by decreasing the IC50 value. In vivo, FITC-GXC specifically accumulated in GC tissue. Moreover, systemic co-injection with GXC peptide and Adriamycin statistically improved the therapeutic efficacy in SGC-7901 xenograft models, surprisingly, without obviously increasing side effects. CONCLUSION: These results demonstrated that co-administration of the novel peptide GXC with chemotherapeutic agents may be a potential way to enhance the efficacy of anticancer drugs in GC treatment.

Treatment of acute tubular necrosis by autologous bone marrow stem cells transplantation through renal artery in the rabbits / 中国病理生理杂志

AIM: To observe the effects and location of autologous bone marrow stem cells(BMSCs) transplanted through renal artery into ischemic-reperfusion(I/R) injured kidney.METHODS: BMSCs were collected from rabbits after isolated and then labeled with 5-bromo-2-deoxyuridine(BrdU).Twenty-eight rabbits were subjected to clamping renal pedicles for 105 min and divided into the transplantation group and control group randomly.BrdU labeled BMSCs or saline were injected into the kidney by renal artery,respectively.Before and after I/R at the 1st,3rd, 5th,7th,14th,21th and 28th d,the venous blood was collected to measure serum Cr and BUN.In the same time,renal tissue was collected for pathological and immunohistochemical study.RESULTS: After I/R,serum Cr and BUN levels in the rabbits in two groups became higher,and on the 1st and 3rd d after I/R,reached the highest level.On the 7th d the serum Cr and BUN levels in transplantation group were lower than those in control group.On the 28th d the levels of serum Cr(90.1?11.1) ?mol/L and BUN(8.0?1.5) mmol/L in transplantation group were significantly lower than those in control group(135.6?32.5) ?mol/L and(10.9?2.5) mmol/L,respectively(P