HSA-MnO₂-¹³¹I Combined Imaging and Treatment of Anaplastic Thyroid Carcinoma

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.