Construction Of Ferroptosis Antitumor Nanosystems Targeting Hepatoma Cells And Experimental Studies Of Their Activities

Liver cancer is one of the most common malignant tumors,ranking sixth in incidence and third in mortality among all tumors.Hepatocellular carcinoma(HCC)accounts for about 90%of all primary liver cancers.Since most of patients are diagnosed at an intermediate or advanced stage,resulting in poor outcomes for liver cancer treatment.Significant improvements have been made in the treatment of liver cancer,but recent years have seen a slowdown in improvement as many treatment strategies have reached the limits of intensive therapy.Furthermore,the side effects become more obvious during long-term treatments.Therefore,developing effective measures for liver cancer treatment and reducing the toxic side effects remain a major challenge for current liver cancer therapy.As a new target for cancer therapy,ferroptosis has attracted widespread attention.Ferroptosis is a non-apoptotic regulated cell death that can be initiated by inhibition of antioxidant defenses and accumulation of iron-dependent reactive oxygen species(ROS).Over the past few years,studies suggested that ferroptosis hold great potential to inhibit tumor growth and metastasis as well as overcome tumor resistance.Therefore,induction of ferroptosis may provide new approaches to tumor therapy.Recently,with the rapid development of nanotechnology,nano-drug delivery systems have shown advantages in drug targeted delivery,effect-enhancing and toxicity-reducing as well as multimodal combined therapy.In particular,nano-drug delivery systems inducing ferroptosis hold great promise for clinical tumor therapy.This research paper is aimed to the construction of multifunctional nano-drug delivery systems for HCC treatment by inducing ferroptosis in HCC cells.The specific research contents are as follows:(1)In this study,a multifunctional nanomicelle-system with targeting,tracing,and acid responsive ability was synthesized and prepared,which encapsulated chemotherapeutic drugs and photosensitizers,exerting the synergistic effect of chemotherapy and photodynamic therapy by targeting liver cancer cells and then inducing ferroptosis for cancer treatment.Using fluorescein-modified Flu-Br as macroinitiator,triggering atom transfer radical polymerization(ATRP)reaction of the monomer 3-azido-2-hydroxypropyl methacrylate(AHPMA)and the monomer 2-(dimethylamino)ethyl methacrylate(DMAEMA)to form the polymer Flup DMAEMA-p AHPMA.The lactose(Lac)with liver targeting function was modified with an alkynyl linker,and then attached to the azide group on Flu-p DMAEMA-p AHPMA by click chemistry reaction,thereby obtaining the multifunctional polymer Flu-p DMAEMA-p AHPMALac,which containing fluorescent group(Flu),acid-sensitive group(DMAEMA),and targeting group(Lac).Flu-p DMAEMA-p AHPMA-Lac was used as a drug carrier,and self-assembled with the chemo drug Triapine and photosensitizer Ce6 to form a multifunctional nanomicelle drug delivery system TCLMs.The average size of TCLMs was 195.2 ? 0.3 nm,and the Zeta potential value was-4.3 ± 2 m V.The drug loading capacity(DLC)of Triapine and Ce6 in TCLMs was 22.2 ± 1.2% and 24.7 ± 1.8%,respectively,and the drug encapsulation efficiency(DEE)was measured as 71.6 ± 3.1% and 52.2 ± 2.0%,respectively.In vitro,TCLMs presented good stability,biocompatibility,and ROS generation ability.Meanwhile,TCLMs inhibited cell proliferation by targeting ferroptosis in HCC cells.In subcutaneous HCC-bearing models,TCLMs can actively target tumor tissues,and effectively inhibit tumor growth with tumor inhibition rates of 85.7% in the presence of NIR.In orthotopic HCC-bearing models,the light source was introduced to the surface of the hepatocellular carcinoma in situ through optical fiber intervention,which enhanced the penetration and reduced the loss of the light source,maximized the effect of photodynamic therapy,and effectively inhibited the tumor growth in situ.(2)In this study,a ferroptosis-inducing metal-organic framework nanodrug delivery system targeting liver cancer was prepared for the treatment of liver cancer stem cells mediated tumor growth and lung metastasis by inhibiting the ferroptosis resistance system composed of GPX4 and FSP1.First,a porous coordination network(Fe-MOF)containing iron ions was synthesized,which was then encapsulated with small-molecule compounds RSL3 and i FSP1 via ?-? stacking,and the surface of the material was modified with lactobionic acid(LA)to generate carbohydrate-based metal-organic framework nanodrug delivery system RF@LA-Fe-MOF.The average size of RF@LA-Fe-MOF was 127.6 ? 2.3 nm,and the Zeta potential value was 12.0 ? 2.24 m V.The DLC and DEE of RSL3 in RF@LA-Fe-MOF was 7.3 ? 0.65% and 70.1 ? 0.97%,respectively,and the DLC and DEE of i FSP1 was measured as 17.8 ? 0.45% and 82.9 ? 1.07%,respectively.In vitro,RF@LA-Fe-MOF exhibited promising ability in ferroptosisinducing,anti-proliferative,and anti-metastatic in HCC cells.Meanwhile,RF@LA-Fe-MOF exerted favorable HCC targeting effects in vitro and in vivo.In subcutaneous HCC-bearing models,RF@LA-Fe-MOF effectively inhibited tumor growth with tumor inhibition rates of 83.0% by triggering ferroptosis,showing good biocompatibility and low toxicity in vivo.In orthotopic HCC-bearing models,RF@LA-Fe-MOF not only inhibited the tumor growth in situ mediated by liver cancer stem cells but also significantly reduced lung metastases,providing a new method for HCC treatment.