Investigation On ROS-responsive Nano Hydrogel System Combines Anti-angiogenic Therapy With Immunotherapy To Overcome Cervical Cancer

Objective:To engineered a ROS-responsive nano-hydrogel co-loaded anti-angiogenic therapy inhibiter and PD-L1 inhibiter,and detected its anti-tumor effects on cervical cancer.Methods:(1)Preparation of hydrogel:prepared and synthesized the PVA solution and ROS-responsive complex ALG-PBA solution,which were skeleton components of the hydrogel.stirred the BMS202 nanoparticles,who was self-assembled by reprecipitation,with PVA solution to formed the PVA coating BMS202 nanoparticles,then mixed the AP solution with it.After mixed or dual-injected the drug loading PVA solution and ROS-responsive complex ALG-PBA,the nano-hydrogel was formed.(2)Investigation to the Characterization of hydrogel:The FT-IR and 1HMR spectrums were detected,the TEM images were captured of BMS nanoparticles and PVA coating BMS nanoparticles,the SEM images were captured of hydrogel;the ROS-response performance,degradation in vivo and biocompatibility were investigated.(3)Investigation of anti-tumor effects in vivo:U14 bearing BALB/c mice were established as animal tumor model.Set group of Control,Gel,AP@Gel,BMS202@Gel,APBMS202@Gel of different treatment,weighted and measured tumor size of the mice every 2days to assessed the tumor growth and survival.Dissociated the tumor tissue and stained with fluorescent antibodies,then detected by FCM to analyses immune cells in tumor.Dissociated the tumor tissue and main organs stained with H&E to evaluated the bio-security of hydrogel.Dissociated the tumor tissue and stained with immunohistochemistry and immunofluorescence to investigated the expression of CD31,α-SMA,PD-L1 and Ki67.Extracted the proteins of tumor tissues and evaluated the expression of PD-L1 by Western Blot.Results:(1)The results of characterization analysis of ALG-PBA indicated the succeed of synthesis.The TEM images of BMS202 nanoparticles and PVA coating BMS202 nanoparticles were met expectation,also as the SEM images of hydrogel.the ROS-response performance,biocompatibility and biodegradation were well.(2)Results of animal experiments showed that,the tumor growth rate of AP-BMS202@Gel was significantly slower than other groups,and the survival duration was longer than other groups.The AP@Gel and BMS202@Gel groups showed the slight delay of tumor growth,and slight extend of survival duration,but has not been controlled in practical.In the analysis of FCM,the increase of CD8+T cells in AP-BMS202@Gel group were significantly differ from other groups.The percentage of MDSCs in APBMS202@Gel group was decreased nearly 50%than Control group,and AP@Gel and BMS202@Gel groups were declined in different degrees.The results of immunohistochemistry and immunofluorescence indicated that,the group of APBMS202@Ge1 showed the highest dual-positive rate of CD31and α-SMA,and the lowest positive rate of HIF-1α,which represented the normalization of vascular and relief of hypoxia.The images of immunofluorescence and western blot showed the APBMS202@Gel and AP@Gel groups were significantly up-regulation of PD-L1 expression,which meant the changed of immunophenotyping.Conclusion:Our survey indicated that,we engineered a ROS-responsive nanohydrogel co-loaded anti-angiogenic therapy inhibiter and PD-L1 inhibiter successfully,which were enhanced anti-tumor effects,relived tumor hypoxia,changed immunophenotyping in animal experiments.