Objective To explore the biological behavior and mechanism of isovitexin(Isov)on pancreatic cancer cells.Methods Isov was used to treat the human normal pancreatic ductal epithelial cells HPDE and PC cell lines,and CCK-8 was used to detect the cell proliferation and calculate the half inhibitory concentration(IC50).The PC cell line PANC-1 cells were grouped into the control group,the Isov group,the Isov+in-miR-NC group,the Isov+in-miR-339-5p group,the Isov+in-miR-339-5p+si-NC group and the Isov+in-miR-339-5p+si-HSPA8 group.The survival,migration and invasion of PANC-1 cells were detected by CCK-8,scratch healing assay and Transwell assay.Real time fluorescence quantitative PCR was used to detect the mRNA expression of miR-339-5p and heat shock protein family A member 8(HSPA8)in PANC-1 cells.Western blot assay was used to detect protein HSPA8 expression in various groups of cells.Dual luciferase reporter gene was used to detect the targeting effect of miR-339-5p and HSPA8.A xenograft nude mouse model was used to determine the in vivo anticancer effects of Isov.Results Isov inhibited PC cell proliferation but had little cytotoxicity to HPDE cells.Isov could obviously reduce the survival rate and scratch healing rate of PANC-1 cells,reduce the number of invasive cells,up-regulate miR-339-5p expression and down-regulate HSPA8 mRNA and protein levels(P＜0.05),while these effects were blocked by down-regulated miR-339-5p(P＜0.05).In addition,HSPA8 was the target gene of miR-339-5p,and knockdown of HSPA8 reversed the regulatory effect of Isov on the malignant biological behavior of PANC-1 cells.In vivo studies confirmed that after Isov treatment,the tumor volume and weight of nude mice decreased,the expression of miR-339-5p was increased and the expression of HSPA8 mRNA was decreased(P＜0.05).Conclusion Isov may inhibit the proliferation,migration and invasion of PC cells through the miR-339-5p/HSPA8 axis.

Objective To explore the biological behavior and mechanism of isovitexin(Isov)on pancreatic cancer cells.Methods Isov was used to treat the human normal pancreatic ductal epithelial cells HPDE and PC cell lines,and CCK-8 was used to detect the cell proliferation and calculate the half inhibitory concentration(IC50).The PC cell line PANC-1 cells were grouped into the control group,the Isov group,the Isov+in-miR-NC group,the Isov+in-miR-339-5p group,the Isov+in-miR-339-5p+si-NC group and the Isov+in-miR-339-5p+si-HSPA8 group.The survival,migration and invasion of PANC-1 cells were detected by CCK-8,scratch healing assay and Transwell assay.Real time fluorescence quantitative PCR was used to detect the mRNA expression of miR-339-5p and heat shock protein family A member 8(HSPA8)in PANC-1 cells.Western blot assay was used to detect protein HSPA8 expression in various groups of cells.Dual luciferase reporter gene was used to detect the targeting effect of miR-339-5p and HSPA8.A xenograft nude mouse model was used to determine the in vivo anticancer effects of Isov.Results Isov inhibited PC cell proliferation but had little cytotoxicity to HPDE cells.Isov could obviously reduce the survival rate and scratch healing rate of PANC-1 cells,reduce the number of invasive cells,up-regulate miR-339-5p expression and down-regulate HSPA8 mRNA and protein levels(P＜0.05),while these effects were blocked by down-regulated miR-339-5p(P＜0.05).In addition,HSPA8 was the target gene of miR-339-5p,and knockdown of HSPA8 reversed the regulatory effect of Isov on the malignant biological behavior of PANC-1 cells.In vivo studies confirmed that after Isov treatment,the tumor volume and weight of nude mice decreased,the expression of miR-339-5p was increased and the expression of HSPA8 mRNA was decreased(P＜0.05).Conclusion Isov may inhibit the proliferation,migration and invasion of PC cells through the miR-339-5p/HSPA8 axis.

Objective:To construct bacterial cytoplasmic membrane nanovesicles(BMV)with overexpressing programmed death 1(PD-1),denoted as BMV-PD-1 and evaluate the targeting efficacy of BMV-PD-1 towards transplanted lung tumor tissues in mice.Methods:The fusion plasmid ClyA-PD-1-EGFP fused by PD-1 and Cytolysin A(ClyA)was transferred into Escherichia coli BL21-Codonplus through plasmid transformation.Laser confocal microscopy,SDS-PAGE,and WB were used to detect the expression of the fusion protein ClyA-PD-1-EGFP.Bacterial membranes were extracted and processed with an extruder to generate BMV-PD-1.TEM and NTA were utilized to assess the morphology,size distribution,and zeta potential of BMV-PD-1,while WB was used to verify the presence of PD-1 protein.Laser confocal imaging was conducted to monitor the uptake of BMV-PD-1 by Lewis lung cancer cells.A C57BL/6J mouse subcutaneous transplant tumor model of LLC lung cancer cells was constructed,and the tumor targeting of BMV-PD-1 was evaluated by small animal imaging system.Results:Laser confocal microscopy images demonstrated that the plasmid ClyA-PD-1-EGFP was transferred into BL21-Codonplus and successfully expressed into protein.SDS-PAGE results suggested that ClyA-PD-1-EGFP was overexpressed in BL21-Codonplus.WB analysis indicated that PD-1 was expressed in bacteria and highly expressed in BMV-PD-1(P<0.001).NTA and TEM analyses revealed that BMV-PD-1 were spherical vesicles with a diameter of(145±14)nm and a negative surface charge.Laser confocal imaging showed that the high expression of PD-1 significantly increased the uptake of BMV-PD-1 by lung cancer cells(P<0.01).In vivo imaging of small animals further confirmed that the high expression of PD-1 can effectively improve cancer targeting of BMV-PD-1(P<0.01).Conclusion:In this study,bacterial plasma membrane nanovesicles BMV-PD-1 with high PD-1 expression are successfully constructed,and it is found that PD-1 overexpression markedly improve the mouse lung cancer xenograft tissue targeting specificity of BMV-PD-1,laying the groundwork for further development of BMV-PD-1 as a carrier for targeted drug delivery systems in tumors.