To explore inhibitory effect of iron oxide nanoparticles loaded with paclitaxel (IONP@PTX) on glioblastoma (GBM) and its potential mechanism. IONP@PTX was synthesized and the characteristics were assessed by chemico-physical analysis and observed directly under transmission electron microscope. U251 cells and HMC3 cells were separately incubated with IONP@PTX and PTX, and then cell viability was detected by Cell Counting Kit-8. The capacity of cell invasive and migration was verified by Scratch wound healing and Transwell migration and invasion assays. Expressions levels of autophagy and ferroptosis biomarkers were demonstrated by Western blotting assay. Intracellular reactive oxygen species (ROS) and lipid peroxidation were detected with DCFH-DA and C11-BODIPY staining, respectively. Intracellular concentration of iron ions was quantified spectrophotometrically. Moreover, inhibitory effect of IONP@PTX on GBM was evaluated by monitoring tumor growth and the toxicity of IONP@PTX was evaluated by measuring the body weight and index of liver and spleen in the mice bearing GBM xenograft. The successfully synthesized IONP@PTX possesses a hydrate diameter about 36 nm and a core diameter around 10 nm. IONP@PTX exerted an inhibitory effect on U251 cells, but had little effect on HMC3 cells compared with PTX alone. In addition, IONP@PTX inhibited the capacity of cell migration and invasion, increased the levels of iron ions, ROS and lipid peroxidation, enhanced the expression of autophagy-related protein Beclin1 and LC3II, and suppressed the expression of p62 and ferroptosis-related protein GPX4 in vitro compared with control group. Moreover, administration of IONP@PTX suppressed tumor volume of GBM xenografts and decreased the expression level of GPX4 protein in tumor tissues in comparison with control group (All P < 0.05). Intriguingly, the effect of IONP@PTX on GBM could be weakened by additional 3-MA or enhanced by additional rapamycin in vitro and in vivo (P < 0.05). More importantly, IONP@PTX had no obvious toxic effect on mice bearing GBM xenograft. IONP@PTX inhibits GBM growth by enhancing autophagy-dependent ferroptosis pathway, thus it might become a potential ferroptosis-inducing agent for ferroptosis-based tumor therapy.

Serological thymidine kinase 1 (STK1) is a reliable proliferation marker for prognosis, monitoring tumour therapy, and relapse. Here we investigated the use of STK1 in health screening for early detection of pre-malignant and malignant diseases. The investigation was based on 35,365 participants in four independent health screening studies in China between 2005–2011. All participants were clinically examined. The concentration of STK1 was determined by a sensitive chemiluminescent dot blot ECL assay. The ROCvalue of the STK1 assay was 0.96. At a cut-off STK1 value of 2.0 pM, the likelihood (+) value was 236.5, and the sensitivity and the specificity were 0.78 and 0.99, respectively. The relative number of city-dwelling people with elevated STK1 values (≥2.0 pM) was 0.8% (198/26,484), while the corresponding value for the group of oil-field workers was 5.8% (514/8,355). The latter group expressed significantly higher frequency of refractory anaemia, fatty liver, and obesity, compared to the city dwellers, but no cases of breast hyperplasia or prostate hyperplasia. Furthermore, people working in oil drilling/oil transportation showed higher STK1 values and higher frequency of pre-malignancies and benign diseases than people working in the oil-field administration. In the STK1 elevated group of the city-dwelling people, a statistically significantly higher number of people were found to have malignancies, pre-malignancies of all types, moderate/severe type of hyperplasia of breast or prostate, or refractory anaemia, or to be at high risk for hepatitis B, compared to people with normal STK1 values (< 2.0 pM). No malignancies were found in the normal STK1 group. In the elevated STK1 group 85.4% showed diseases linked to a higher risk for pre-/early cancerous progression, compared to 52.4% of those with normal STK1 values. Among participants with elevated STK1 values, 8.8% developed new malignancies or progress in their pre-malignancies within 5 to 72 months, compared to 0.2% among people with normal STK1 values. People who showed elevated STK1 values were at about three to five times higher risk to develop malignancies compared to a calculated risk based on a cancer incidence rate of 0.2–0.3%. We conclude that serological TK1 protein concentration is a reliable marker for risk assessment of pre/early cancerous progression.

Background: Compared to the excitation light in photodynamic therapy, ultrasound in sonodynamic therapy (SDT) could easily penetrate into the deep tumor in liver. However, the photosensitizer chlorin e6 (E6) activated by ultrasound has been limited in its application in clinics for the poor water solubility of E6 and poor effect of SDT. Nanoparticles as cavitation promotors may be able to amplify the E6-mediated SDT effect and also improve its water solubility. Objective: The objective of the study was to develop an E6-based sonosensitizer with improved SDT effect and good water solubility using nanotechnology. Materials and methods: Polyethylene glycol (PEG)ylated iron oxide nanoparticles coated with E6 (PION@E6) was prepared by means of pyrolysis and phase transfer. Characterization of PION@E6 was performed by means of transmission electron microscopy, hydrate particle size analysis, and absorption and fluorescence spectra analysis. Uptake of PION@E6 by H22 cells (a murine hepatoma cell line) was measured by inductively coupled plasma atomic emission spectroscopy. The effect of SDT on H22 cells was studied by the combination of ultrasound treatment with PION@E6 incubation. Cell viability was measured using cell counting kit-8 assay. Cell apoptosis was analyzed by flow cytometry. ROS generation was measured using DCFH-DA (2',7'-dichlorodihydrofluorescein diacetate) probing kit. Results: Absorption spectra of PION@E6 revealed successful loading of E6 onto the PIONs. It showed excellent water solubility and stability with a size of 37.86±12.90 nm in diameter. The fluorescence spectra of PION@E6 revealed a red-shift compared with free E6. When combined with ultrasound treatment, it showed a significantly better inhibitory effect on H22 cells and correspondingly higher level of intracellular ROS generation compared with free E6. Furthermore, either higher dose of PION@E6 or higher power intensity of ultrasound initiated significantly better SDT effect and correspondingly higher level of intracellular ROS generation compared with lower dose of PION@E6 or ultrasound, respectively. Conclusion: PION@E6 is a superior potential sonosensitizer to E6 to treat tumors by SDT.

Hepatocellular carcinoma (HCC) is easy to relapse after resection for its lack of anti-tumor immunity due to pro-tumorigenesis by promoting M2 type macrophage polarization. Recent studies have shown that exosomes are closely related to the occurrence and development of HCC. Antigenic exosomes from HCC are able to polarize into alternatively activated macrophages M2, but do not stimulate M1 macrophages polarization. Iron oxide nanoparticles (IONs) have been demonstrated to be able to promote M1 macrophages polarization. This research was to explore exosomes as vehicles to synergize with pegylated IONs loaded with chlorin e6 (PIONs@E6) to enhance their immunity against HCC via promoting M1 macrophages polarization. PIONs@E6 was synthesized and then characterized by chemico-physical analysis, transmission electron microscope (TEM), respectively. After characterization of PIONs-contained exosomes by TEM, and then the exosomal surface specific molecules CD9 and CD63 were determined by Western Blotting assay. Markers of M1 macrophage polarization in vitro and in vivo were analyzed by enzyme linked immunosorbent assay (ELISA) and flow cytometry, respectively. Intracellular reactive oxygen species (ROS) in macrophages were analyzed using a Spectra Max fluorescence microplate reader. Inhibitory effect of PIONs-contained exosomes on HCC was evaluated by monitoring tumor growth in an in vivo xenograft mice model. PIONs@E6 showed good water solubility with a core diameter around 10 nm and a hydrate diameter around 37 nm. The expression of exosome specific markers CD9 and CD63 was kept at a high level. PIONs-contained exosomes can dose-dependently promote M1 macrophages polarization in vitro and in vivo. Of note, PIONs-contained exosomes could initiate a significantly higher level of ROS in macrophages and remarkably inhibit the tumor growth in mice bearing HCC xenograft. Exosomes as vehicles could be synergized with PIONs@E6 to enhance their immunity against HCC via promoting M1 macrophages polarization.