Drug delivery particles for targeted imaging-guided photothermal/chemotherapy synergy cancer therapy.

The early stage of pancreatic cancer is asymptomatic and the treatment effect is not ideal. The progression to the advanced stage leads to a close relationship between mortality and morbidity. Therefore, there is an urgent need to develop precise and efficient therapeutic strategies to combat pancreatic cancer. In this study, we introduce a near-infrared (NIR) targeted drug delivery nanoparticle for ultrasound (US) imaging to guide magnetothermal/chemotherapy synergistic treatment of pancreatic cancer. Carboxylated polylactic acid (PLGA-PEG-COOH) serves as the structure of the nanoparticles, specifically binding the RGD cyclic peptide for pancreatic cancer targeting activity and promoting tumor aggregation of the nanoparticles. NIR-induced superparamagnetic iron oxide (SPIO) nanoparticles convert near-infrared light into thermal energy, triggering vaporization of perfluoropentane (PFH) droplets to generate PFH bubbles that enhance US imaging and help load doxorubicin (DOX), which are released from nanoparticles. SPIO can also be used for thermal ablation of tumors to improve therapeutic effect in treating pancreatic cancer. The results show that the targeted particles mediated by NIR have the characteristics of targeted drug delivery imaging. The microspheres exhibit strong acoustic and near-infrared responsiveness. Cell proliferation experiments showed that IR-mediated PFH-DOX@PLGA/SPIO-RGD NPs (RNPs) had a higher inhibitory effect on cell proliferation. Animal experiments have shown that RNPS can accumulate highly in the tumor area and show good therapeutic effect. In conclusion, this nanotherapeutic particle is a very promising targeted image-guided photothermal/chemotherapeutic synergistic tumor therapy strategy.

Ultrasound-mediated multifunctional magnetic microbubbles for drug delivery of celastrol in VX2 liver transplant tumors.

Celastrol (CST) has positive pharmacological effects on various cancers, but clinical application is limited because of poor water solubility and systemic toxicity. Ferric oxide (Fe3O4) has a large specific surface area and can be functionalized by inorganic modification to form complex magnetic drug delivery systems. Herein, Fe3O4 was surface-modified with citric acid and polyethylene glycol (PEG) (via) the Mitsunobu reaction and then covalently bound to CST. Finally, magnetic microbubbles (MMBs) containing perfluoropropane (C3F8) and Fe3O4-PEG2K-CST particles were constructed with poly(lactic-co-glycolic acid) (PLGA) as the shell membrane. In vitro studies showed that ultrasound-mediated MMBs exhibited improved inhibition of VX2 cell proliferation compared to inhibition achieved using MMBs without ultrasound mediation, blank MMBs, or free CST. In ultrasound mode, MMBs have favorable imaging properties. After the application of a high mechanical index, MMBs collapse through the cavitation effect, releasing their internal Fe3O4-PEG2K-CST. The CST is then delivered to the tumor microenvironment under acidic conditions. In magnetic resonance imaging T2 mode, a specific hypointense signal was observed in the tumor area compared with that before treatment, whereas no significant change occurred in the signal intensity of the surrounding organs. After treatment, pathological examination of tumor-bearing rabbit tissues showed that iron elements accumulated in several apoptosis cells in the tumor area, with no apparent abnormalities found in other areas. Thus, ultrasound-mediated MMBs could significantly improve the drug uptake of solid tumors and inhibit tumor growth with favorable biological safety.

Clinicopathologic characteristics of inflammatory pseudotumor-like follicular dendritic cell sarcoma.

Inflammatory pseudotumor (IPT)-like follicular dendritic cell (FDC) sarcoma is a recently described rare tumor and considered a unique entity, with different histologic appearances and behavior from those of the classical FDC sarcoma. This study analyzed the clinical and pathological findings of two such cases that the authors encountered and 36 previously reported cases identified in the literature. Assessment of all 38 cases showed a slight female predominance (2.2:1) with a median age of 56.5 years. Seventeen patients complained of abdominal discomfort or pain, while fifteen patients had no clinical symptom. Almost all cases occurred in liver (n=20) or spleen (n=17). Except in one case, all patients underwent surgical resection of the tumor alone. Histologic features showed a mixture of chronic inflammatory cells and variable amounts of spindle cells with vesicular nuclei and distinct nucleoli. The tumor cells expressed conventional FDC markers such as CD21 (75%), CD35 (92%), CD23 (62%), clusterin (75%), and CNA.42 (100%). EBV was detected in thirty-five cases (92.1%) by Epstein-Barr virus (EBV)-encoded RNA in situ hybridization, and EBV-latent membrane protein-1 was expressed in 90% of the cases. With a median follow-up of 21 months, 29 patients (85.3%) were alive and well, 4 (11.8%) were alive with disease, one patient (2.9%) died of disease. Only four patients with hepatic tumors underwent recurrence or metastasis after initial treatment. Epstein-Barr virus is thought to play a role in the development of the tumor; however, the pathogenesis of the disease and the origin of tumor cells remain unclear.