Hyperthermia mediated by dextran-coated La0.7Sr0.3MnO3 nanoparticles: in vivo studies

Abstract

Purpose The aim of this study was to evaluate radiofrequency-induced dextran-coated lanthanum strontium manganese oxide nanoparticles-mediated hyperthermia to be used for tumor regression in mice. Materials and methods Nanoparticles were injected intra-tumorally in melanoma-bearing C57BL/6J mice and were subjected to radiofrequency treatment. Results Hyperthermia treatment significantly inhibited tumor growth (~84%), increased survival (~50%), and reduced tumor proliferation in mice. Histopathological examination demonstrated immense cell death in treated tumors. DNA fragmentation, increased terminal deoxynucleotidyl transferase-dUTP nick end labeling signal, and elevated levels of caspase-3 and caspase-6 suggested apoptotic cell death. Enhanced catalase activity suggested reactive oxygen species-mediated cell death. Enhanced expression of heat shock proteins 70 and 90 in treated tumors suggested the possible development of “antitumor immunity”. Conclusion The dextran-coated lanthanum strontium manganese oxide-mediated hyperthermia can be used for the treatment of cancer.

Hyperthermia Suppresses Post - In Vitro Proliferation and Tumor Growth in Murine Malignant Melanoma and Colon Carcinoma

“…A prominent finding in our study was the activation of the apoptotic pathway as evidenced by an increased expression of cleaved caspase-3 in both hyperthermia-treated groups. These results are in accordance with our previous in vitro findings together with observations, by other groups, showing the involvement of caspase-3 in triggering the apoptotic response in a number of different therapeutic protocols combined with hyperthermia (45,46,48,51). In contrast, COX-2 was shown to be expressed in significantly lower levels in the tumors of both hyperthermia-treated groups, a finding also in agreement with earlier studies exhibiting an increased expression of COX-2 in metastatic melanoma lesions and cell lines while being undetected in lesions of primary stages (53).…”

“…Furthermore, we have shown a remarkably prominent inhibition of tumor volume and size between hyperthermic and control conditions which further supports the significance of hyperthermia's therapeutic potential. A large number of studies are also in agreement with our in vivo findings although their focus was primarily on determining the efficacy of various clinical therapeutic protocols in combination with hyperthermia (43)(44)(45)(46)(47)(48)(49)(50)(51)(52).…”

Metallic nanoparticles for cancer immunotherapy

“…Interestingly, the mechanisms initiated by hyperthermia do not rely on CD4+ T cell expansion or IL-12 to support the propagation of the immune response[73]. This protective immunity effect against tumor rechallenge can also be observed following MNP-mediated ablation approaches including gold-nanoshell PTT, titanium oxide-mediated ultrasound, or MNP-enabled RF hyperthermia[75, 112, 121, 122].…”

Treatment of Breast Cancer-Bearing BALB/c Mice with Magnetic Hyperthermia using Dendrimer Functionalized Iron-Oxide Nanoparticles

“…Many studies were performed on magnetic hyperthermia using different functionalized MNPs on animal models of cancer [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 ] ( Table 1 ). Generally speaking, their results were promising and showed a significant remission in the tumor size after treatment.…”