<p>cRGD-Conjugated Fe₃O₄@PDA-DOX Multifunctional Nanocomposites for MRI and Antitumor Chemo-Photothermal Therapy</p>

Abstract

Background: Photothermal therapy (PTT) has great potential in the clinical treatment of tumors. However, most photothermal materials are difficult to apply due to their insufficient photothermal conversion efficiencies (PCEs), poor photostabilities and short circulation times. Furthermore, tumor recurrence is likely to occur using PTT only. In the present study, we prepared cyclo (Arg-Gly-Asp-d-Phe-Cys) [c(RGD)] conjugated doxorubicin (DOX)-loaded Fe 3 O 4 @polydopamine (PDA) nanoparticles to develop a multifunctionaltargeted nanocomplex for integrated tumor diagnosis and treatment. Materials and methods: Cytotoxicity of Fe 3 O 4 @PDA-PEG-cRGD-DOX against HCT-116 cells was determined by cck-8 assay. Cellular uptake was measured by confocal laser scanning microscope (CLSM). Pharmacokinetic performance of DOX was evaluated to compare the differences between free DOX and DOX in nanocarrier. Performance in magnetic resonance imaging (MRI) and antitumor activity of complex nanoparticles were evaluated in tumor-bearing nude mice. Results: Fe 3 O 4 @PDA-PEG-cRGD-DOX has a particle size of 200-300 nm and a zeta potential of 22.7 mV. Further studies in vitro and in vivo demonstrated their excellent capacity to target tumor cells and promote drug internalization, and significantly higher cytotoxicity with respect to that seen in a control group was shown for the nanoparticles. In addition, they have good thermal stability, photothermal conversion efficiencies (PCEs) and pH responsiveness, releasing more DOX in a mildly acidic environment, which is very conducive to their chemotherapeutic effectiveness in the tumor microenvironment. Fe 3 O 4 @PDA-PEG-cRGD-DOX NPs were used in a subcutaneous xenograft tumor model of nude mouse HCT-116 cells showed clear signal contrast in T2-weighted images and effective antitumor chemo-photothermal therapy under NIR irradiation. Conclusion: According to our results, Fe 3 O 4 @PDA-PEG-cRGD-DOX had a satisfactory antitumor effect on colon cancer in nude mice and could be further developed as a potential integrated platform for the diagnosis and treatment of cancer to improve its antitumor activity against colon cancer.

Nanoparticles and Gut Microbiota in Colorectal Cancer

“…Conjugation of these NPs to chemotherapeutic drugs did not only effectively kill tumor cells via active targeting, but also inhibited tumor growth using near-infrared (NIR) irradiation due to the photothermal activity of the NPs (Fan et al, 2019). In another study, Fe 2 O 3 -gold NPs were observed to accumulate within the tumor mass instead of other organs in a colon cancer model, while also enhancing the tumor detection selectivity as MRI contrast agents in a pancreatic cancer model (Kumagai et al, 2010).…”

Utilization of metal or non-metal-based functional materials as efficient composites in cancer therapies

“…57 However, the use of PTT alone has limitations: light penetration depth is limited, it resulted in incomplete elimination of cancer cells, and the residual edge of the treatment area may lead to the recurrence of the disease. 58,59 Immunotherapy plays an important role in the treatment of metastatic tumors. The combination of physical effect and influence can not only eliminate tumor cells through hyperthermia, but also improve the release of antigens in the body to enhance the immune response.…”

Co-Modification With Mesenchymal Stem Cells Membrane and PDA Prevents Fe3O4-Induced Pulmonary Toxicity in Micevia AMPK-ULK1 Axis

“…This neurotransmitter can self-aggregate to form polydopamine (PDA) under speci c conditions. Because of the high biocompatibility and biodegradability, PDA has been widely used in the camou age of nanoparticles and various biomedical applications [12].PDA-coated magnetic nanostructureshave good thermal stability, photothermal conversion e ciencies, pH responsiveness,biocompatibility and low genotoxicity [13][14][15].Some studies have shown that the use of PDA modi cation can signi cantly improve the biocompatibility of Fe 3 O 4 , but it still shows a certain degree of cytotoxicity. Therefore, the development of new modi cation methods is an urgent need for the clinical application of Fe 3 O 4 .…”