Application Of Multifunctional Iron-based Organic Framework Materials In The Treatment Of Oral Squamous Cell Carcinoma

Objectives:The incidence rate of oral squamous cell carcinoma ranks sixth among all cancers,which seriously affects the appearance and quality of life of patients and is also the main cause of cancer death.Although great progress has been made in diagnosis and treatment,the 5-year survival rate is still less than 50%,so it is necessary to develop new and effective treatment methods.Photodynamic therapy(PDT)is a new non-invasive treatment method,which has been widely used in the treatment of human oral squamous cell carcinoma.On the other hand,significant progress has been made in the design and development of anticancer drugs based on inducing iron death of tumor cells.Nanoparticles show unique advantages in inducing iron death of tumor cells due to their low toxicity,high stability and high carrier capacity.Iron based organic framework(FeMOF)is a subclass of MOF structure,which has excellent chemical and thermal stability under water and physiological conditions.Its structural surface area is large,and its cytotoxicity is negligible,but it is easy to decompose under acidic conditions(pH5.0～6.0).In this study,FeMOF was used as a nano-carrier to modify the targeted peptide on the surface of the carrier,and then adsorb iron death inducer and photosensitizer to develop a new type of anti-tumor nano-material MIL-53@cMBP@SRF-Ce6,to achieve the targeted release of therapeutic drugs,reduce the systemic toxicity and side effects of chemotherapy drugs,and achieve the synergistic anticancer effect of photodynamic therapy and chemotherapy drugs.Methods:1.Synthesis and characterization of materials.Nano-metallic organic framework MIL-53 was prepared by oil bath stirring method,and then polyethylene glycol(PEG)was modified on its surface,followed by targeted polypeptide(cMBP)MIL-53@cMBP(MM).Finally,the iron death inducer sorafenib(SRF)and photosensitizer dihydroporphyrin e6(Ce6)were adsorbed on MM to build a nano anti-tumor treatment platform,expressed as MIL-53@cMBP@SRF-Ce6(MMSC);It was characterized by transmission electron microscopy(TEM),dynamic light scattering(DLS),X-ray diffraction spectroscopy(XRD),Fourier transform infrared absorption spectroscopy(FTIR)and other instruments.2.Evaluation of the performance of nanoparticles: understand the degradation behavior and stability test of nanomaterials in vitro.DLS detects the change of the particle size of MIL-53 in different pH conditions and solutions.Evaluate the catalytic performance in vitro(including catalase activity,peroxidase activity and · OH generation).3.Study on antitumor effect and mechanism in vitro: establish cell model with Cal-27 cells for cytotoxicity test;Hoechst/PI staining reagent was used to carry out the live/dead staining experiment on Cal-27 cells to detect the viability of cells treated with nanomaterials;DCFH-DA probe was used to detect the changes of intracellular reactive oxygen species(ROS)level;Western blot was used to verify the anti-tumor mechanism and material targeting function of nanomaterials.4.Preliminary evaluation of safety: HaCaT cells were used to establish a model to detect the toxicity of nanomaterials to normal cells,and fresh eye blood of mice was used for hemolysis test of materials.Results:1.Synthesis and characterization of MMSC: The anti-tumor nanometer preparation MMSC was successfully synthesized by chemical methods.TEM results showed that the MMSC nanoparticles had uniform spherical shape;DLS results show that the hydrated particle size of the nanoparticles is about 128.2 ± 0.1nm;Its Zeta potential value is-15.4 m V;FTIR showed that the cMBP polypeptide was successfully modified on the surface of the material.XDR suggested that the encapsulation of sorafenib and porphyrin e6 did not affect the crystal structure of MIL53.2.Evaluation results of nanoparticle performance: DLS detected that the particle size of MIL-53 changed significantly in acidic environment,and weak acid environment can destroy the framework of MIL-53;It has good stability in water and DMEM+10% FBS solution;The dissolved oxygen experiment shows that MMSC can catalyze H2O2 to generate O2,and the nano material has catalase-like activity.After TMB and H2O2 are added to the nano-material solution,a typical absorption peak can be observed at 652nm;Through MB degradation experiment,it was detected that MMSC could catalyze the decomposition of H2O2 to generate · OH,and its catalytic decomposition ability was concentration dependent,which fully showed that MMSC had POD-like enzyme activity,and in acidic environment,MMSC had higher POD-like enzyme activity.3.Research results of anti-tumor effect and mechanism in vitro: Cal-27 cytotoxicity test results showed that MMSC could effectively destroy tumor cells under near-infrared(NIR)light irradiation;Using DCFH-DA probe,it was found that a large amount of ROS was produced in the cells after MMSC+NIR treatment;Western blot showed that the expression of GPX4 and p-MET in tumor cells decreased significantly after MMSC+NIR treatment.4.Preliminary safety evaluation results: MIL-53 and MMSC have no obvious cytotoxicity to HaCaT cells;Cell hemolysis test showed that the material did not cause obvious hemolysis.Conclusion:A new type of anti-tumor nano-material MMSC has been successfully developed.The nano-particles have uniform morphology,suitable particle size,good biocompatibility and low toxicity.Under near-infrared light irradiation,it can effectively kill tumor cells,and preliminarily explore the anti-tumor mechanism.