Abstract
Purpose Compelling evidence suggests that nanoparticles (NPs) play a crucial role in cancer therapy. NPs templated with human serum albumin (HSA) has good retention in tumors. Manganese dioxide (MnO2) has been used to enhance the effect of radiotherapy. In this study, synthesized NPs using HSA-MnO2 labeled 131I to perform both imaging and therapy for anaplastic thyroid carcinoma (ATC). Method HSA-MnO2 was synthesized via HSA using a simple biomineralization method, and then labeled with Na131I by the chloramine T method. The cytotoxicity and biosafety of HSA-MnO2 were evaluated by the MTT test. The proliferation-inhibiting effect of HSA-MnO2-131I was evaluated in papillary thyroid cancer cell lines (K1, BCPAP, and KTC) and anaplastic thyroid carcinoma cell lines (Cal62, THJ16T, and ARO). For further translational application in medicine, we established a model of transplantable subcutaneously tumors in BALB\c-nu mice to assess the anti-tumor effect of HSA-MnO2-131I. The imaging effects of NPs were evaluated by MRI and SPECT/CT. Results The MTT test proved that the HSA-MnO2 had low toxicity. HSA-MnO2-131I significantly inhibited the proliferation of PTC and ATC cell lines. In addition, the results unveiled that HSA-MnO2-131I exhibited dual-modality MR/SPECT imaging for thyroid cancer visualization. In particular, HSA-MnO2-131I had an enhanced T1 signal in MR. Using SPECT/CT, we observed that HSA-MnO2-131I had good retention in tumor tissue, which was helpful for the diagnosis and treatment of tumor. In vivo assays indicated that the NPs led to a reduction in radioresistance in the tumor hypoxic microenvironment. Conclusion The nanomaterial had a simple synthesis method, good water solubility and biosafety, and good retention in tumor tissue. Hence, it could be used for SPECT/CT and MR dual mode imaging and therapy with radioiodine of tumor cells. The experimental results provided a feasible solution for combining radiotherapy and dual-model imaging by NPs for cancer diagnosis and treatment.