IOP Injection, A Novel Superparamagnetic Iron Oxide Particle MRI Contrast Agent for the Detection of Hepatocellular Carcinoma: A Phase II Clinical Trial.

BACKGROUND: MRI is crucial in diagnosing hepatocellular carcinoma (HCC). Superparamagnetic iron oxide particles (SPIO) are liver-specific contrast agents which enhance lesions in T2 -weighted images. Iron oxide nano-particle m-PEG-silane (IOP) Injection, a newly developed SPIO, showed promising imaging effects and good safety profile in preclinical studies and in phase I clinical trial. PURPOSE: To evaluate the safety and clinical validity of IOP Injection as MRI contrast agent in diagnosing HCC. STUDY TYPE: Prospective. SUBJECTS: A total of 52 subjects (61.6 ± 11.05 years, 45 males/7 females) with suspected HCC. FIELD STRENGTH/SEQUENCE: 1.5 T, T1 -weighted in/opposed phase, T2 *-weighted gradient echo, T2 -weighted fast spin echo, true fast imaging with steady-state free precession. ASSESSMENT: Adverse effects and clinical monitoring were recorded throughout the 5-day study. Two independent readers (M.G.H. with 30 years of experience, S.P.K. with 26 years of experience) made the diagnosis. The diagnostic performance of IOP-enhanced MRI was evaluated with sensitivity and positive predictive value by comparing to the pathology reports from subsequent hepatic resection. The number of lesions with various sizes and degrees of differentiation detected by IOP-enhanced MRI was assessed. The relative change in signal intensities over time was indirectly measured from acquired images. STATISTICAL TESTS: Sensitivity and positive predictive value were used to evaluate the diagnostic performance of IOP-enhanced MRI. Prevalence-adjusted and bias-adjusted 𝜅 coefficient was used to assess the interreader variability. RESULTS: No serious adverse event related to IOP Injection was found. IOP Injection enhanced the lesion-to-liver contrast ratio in T2 *-weighted images by 50.1% ± 4.8%. IOP-enhanced MRI detected HCC with 100% sensitivity by subject and 96% sensitivity by lesion. IOP Injection visualized subtle vascular invasion as filling defect within vessels in true fast imaging with steady-state free precession (TrueFISP) images. DATA CONCLUSION: IOP Injection was safe and efficacious as MRI contrast agent in diagnosing HCC in a limited group of subjects. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 2.

Exercise improves the outcome of anticancer treatment with ultrasound-hyperthermia-enhanced nanochemotherapy and autophagy inhibitor.

It has been shown that exercise has a direct impact on tumor growth along with functional improvement. Previous studies have shown that exercise decreases the risk of cancer recurrence across various types of cancer. It was indicated that exercise stimulates the immune system to fight cancer. Previous study demonstrated that pulsed-wave ultrasound hyperthermia (pUH) combined with PEGylated liposomal doxorubicin (PLD) and chloroquine (CQ) inhibits 4T1 tumors growth and delays their recurrence. In this study, we investigated if the combinatorial treatment with high-intensity interval training (HIIT) combined with pUH-enhanced PLD delivery and CQ improved the outcome. The mouse experiment composed of three groups, HIIT+PLD+pUH+CQ group, PLD+pUH+CQ group, and the control group. HIIT+PLD+pUH+CQ group received 6 weeks of HIIT (15 min per day, 5 days per week) before 4T1 tumor implantation. Seven days later, they received therapy with PLD (10 mg/kg) + pUH (3 MHz, 50% duty cycle, 0.65 W/cm2, 15min) + CQ (50 mg/kg daily). Results showed that HIIT+PLD+pUH+CQ significantly reduced the tumor volumes and brought about longer survival of tumor-bearing mice than PLD+pUH+CQ did. Blood cell components were analyzed and showed that neutrophil and reticulocytes decreased while lymphocytes increased after exercise.

Combination Therapy of Pulsed-Wave Ultrasound Hyperthermia and Immunostimulant OK-432 Enhances Systemic Antitumor Immunity for Cancer Treatment.

PURPOSE: In this study, we hypothesized that systemic antitumor immunity might be enhanced by combining pulsed-wave ultrasound hyperthermia (pUSHT) with OK-432 and that the induced antitumor immunity could confer protection against tumorigenesis. These hypotheses were tested in bilateral and rechallenged tumor models. METHODS AND MATERIALS: Bilateral and rechallenged tumor models were applied in the studies. In the bilateral tumor model, BALB/c mice were inoculated in both flanks with CT26-luc tumor cells. The tumors in the right flank were treated with 4 courses of pUSHT with or without OK-432. In the rechallenged tumor model, tumor cells were implanted into the right flank. Once formed, the tumors were treated with pUSHT with OK-432, followed by surgical resection. New tumor cells were then implanted into the contralateral flank. The antitumor response was evaluated via infiltrated immune cells and the severity of necrosis/apoptosis in tumors. RESULTS: In the bilateral tumor model, the tumor growth rate and growth activity of both treated (100% reduction) and untreated tumors (90.5% reduction) were significantly inhibited with the combination treatment compared with the sham control group, and the systemic antitumor effect was prolonged. The survival rate was significantly enhanced (sham control, 8 days; OK plus pUSHT, >20 days). IFNγ+ CD4 (treated tumor, 8.6-fold; untreated tumor, 4-fold), IFNγ+ CD8 (treated tumor, 6.7-fold; untreated tumor, 2.6-fold), and T cell and NK cell (treated tumor, 4-fold; untreated tumor, 2.5-fold) infiltration was increased in the combination group compared with the control group. In the rechallenged tumor model, new tumors failed to form with the combination treatment. CONCLUSION: This experimental study combining pUSHT and OK-432 explored a new therapeutic strategy for controlling colon cancer metastasis. The results show that the combination treatment may produce an effective antitumor immune response.

Pulsed-wave Ultrasound Hyperthermia Enhanced Nanodrug Delivery Combined with Chloroquine Exerts Effective Antitumor Response and Postpones Recurrence.

Autophagy is found to serve as a surviving mechanism for cancer cells. Inhibiting autophagy has been considered as an adjuvant anti-cancer strategy. In this study, we investigated the anti-tumor effect of combining pulsed-wave ultrasound hyperthermia (pUH) enhanced PEGylated liposomal doxorubicin (PLD) delivery with an autophagy inhibitor chloroquine (CQ). BALB/c mice bearing subcutaneous 4T1 tumor received intravenous injection of PLD (10 mg/kg) plus 15-minute on-tumor pUH on Day 5 after tumor implantation and were then fed with CQ (50 mg/kg daily) thereafter. Prolonged suppression of tumor growth was attained with PLD + pUH + CQ treatment, whereas in PLD + pUH group tumors quickly recurred after an initial inhibition. Treatment with CQ monotherapy had no benefit compared to the control group. Immunohistochemical staining and Western blotting showed that autophagy of cancer cells was blocked for the mice receiving CQ. It indicates that PLD + pUH + CQ is a promising strategy to treat cancer for a long-term inhibition.

Pulsed-wave low-dose ultrasound hyperthermia selectively enhances nanodrug delivery and improves antitumor efficacy for brain metastasis of breast cancer.

The clinical application of chemotherapeutics for brain tumors remains a challenge due to limitation of blood-brain barrier/blood-tumor barrier (BBB/BTB). In this study, we investigated the effects of low-dose focused ultrasound hyperthermia (UH) on the delivery and therapeutic efficacy of pegylated liposomal doxorubicin (PLD) for brain metastasis of breast cancer. Murine breast cancer cells (4T1-luc2) expressing firefly luciferase were implanted into mouse striatum as a brain tumor model. The mice were intravenously injected with PLD with/without transcranial pulsed-wave/continuous-wave UH (pUH/cUH) treatment on day-6 after tumor implantation. pUH (frequency: 500kHz, PRF: 1000Hz, duty cycle: 50%) was conducted under equal acoustic power (2.2-Watt) and sonication duration (10-min) as cUH. The amounts of doxorubicin accumulated in the normal brain and tumor tissues were measured with fluorometry. The tumor growth responses for the control, pUH, PLD, PLD+cUH, and PLD+pUH groups were evaluated with IVIS. The PLD distribution and cell apoptosis were assessed with immunofluorescence staining. The results showed that pUH significantly enhanced the PLD delivery into brain tumors and the tumor growth was further inhibited by PLD+pUH without damaging the sonicated normal brain tissues. This indicates that low-dose transcranial pUH is a promising method to selectively enhance nanodrug delivery and improve the brain tumor treatment.

Doxorubicin-modified magnetic nanoparticles as a drug delivery system for magnetic resonance imaging-monitoring magnet-enhancing tumor chemotherapy.

In this study, we developed functionalized superparamagnetic iron oxide (SPIO) nanoparticles consisting of a magnetic Fe3O4 core and a shell of aqueous stable polyethylene glycol (PEG) conjugated with doxorubicin (Dox) (SPIO-PEG-D) for tumor magnetic resonance imaging (MRI) enhancement and chemotherapy. The size of SPIO nanoparticles was ~10 nm, which was visualized by transmission electron microscope. The hysteresis curve, generated with vibrating-sample magnetometer, showed that SPIO-PEG-D was superparamagnetic with an insignificant hysteresis. The transverse relaxivity (r 2) for SPIO-PEG-D was significantly higher than the longitudinal relaxivity (r 1) (r 2/r 1 >10). The half-life of Dox in blood circulation was prolonged by conjugating Dox on the surface of SPIO with PEG to reduce its degradation. The in vitro experiment showed that SPIO-PEG-D could cause DNA crosslink more serious, resulting in a lower DNA expression and a higher cell apoptosis for HT-29 cancer cells. The Prussian blue staining study showed that the tumors treated with SPIO-PEG-D under a magnetic field had a much higher intratumoral iron density than the tumors treated with SPIO-PEG-D alone. The in vivo MRI study showed that the T2-weighted signal enhancement was stronger for the group under a magnetic field, indicating that it had a better accumulation of SPIO-PEG-D in tumor tissues. In the anticancer efficiency study for SPIO-PEG-D, the results showed that there was a significantly smaller tumor size for the group with a magnetic field than the group without. The in vivo experiments also showed that this drug delivery system combined with a local magnetic field could reduce the side effects of cardiotoxicity and hepatotoxicity. The results showed that the developed SPIO-PEG-D nanoparticles own a great potential for MRI-monitoring magnet-enhancing tumor chemotherapy.

Targeting microbubbles-carrying TGFß1 inhibitor combined with ultrasound sonication induce BBB/BTB disruption to enhance nanomedicine treatment for brain tumors.

The clinical application of chemotherapy for brain cancer tumors remains a challenge due to difficulties in the transport of therapeutic agents across the blood-brain barrier/blood-tumor barrier (BBB/BTB). In this study, we developed des-octanoyl ghrelin-conjugated microbubbles (GMB) loaded with TGFß1 inhibitor (LY364947) (GMBL) to induce BBB/BTB disruption for ultrasound (US) sonication with GMBL. The in-vitro stability study showed that GMB was pretty stable over one month. The in-vivo study showed that the accumulation of superparamagnetic iron oxide nanoparticles (SPION) in the sonicated tumor was significantly higher for focused US sonication in the presence of GMBL, indicating that GMBL/US can locally disrupt BBB/BTB to promote vascular permeability of nanoparticles. In addition, the combination of folate-conjugated polymersomal doxorubicin (FPD) and GMBL/US (FPD+GMBL/US) achieved the best anti-glioma effect and significant improvement in the overall survival time for brain tumor-bearing mice. When combined with focused US, GMBL facilitated local BBB/BTB disruption and simultaneously released LY364947 to decrease the pericyte coverage of the endothelium at the targeted brain tumor sites, resulting in enhanced accumulation and antitumor activity of FPD. The overall results indicate that GMBL/US owns a great potential for non-invasive targeting delivery of nanomedicine across the BBB to treat central nervous system (CNS) diseases.

Polymersomes conjugated with des-octanoyl ghrelin and folate as a BBB-penetrating cancer cell-targeting delivery system.

Chemotherapy for brain cancer tumors remains a big challenge for clinical medicine due to the inability to transport sufficient drug across the blood-brain barrier (BBB) and the poor penetration of drug into the tumors. To effectively treat brain tumors and reduce side effects on normal tissues, both des-octanoyl ghrelin and folate conjugated with polymersomal doxorubicin (GFP-D) was developed in this study to help transport across the BBB and target the tumor as well. The size measurements revealed that this BBB-penetrating cancer cell-targeting GFP-D was about 85 nm. In-vitro experiments with a BBB model and C6 glioma cells demonstrated that GFP-D owned a robust penetrating-targeting function for drug delivery. In C6 cell viability tests, GFP-D exhibited an inhibitory effect significantly different from the unmodified polymersomal doxorubicin (P-D). In-vivo antitumor experiments showed that GFP-D performed a much better anti-glioma effect and presented a significant improvement in the overall survival of the tumor-bearing mice as compared to the treatments with free doxorubicin (Dox), liposomal doxorubicin (L-D), P-D, or single ligand conjugated P-D. In addition, Cy 5.5 was used as a probe to investigate the delivery property of this penetrating-targeting delivery system. The overall experimental results indicate that this BBB-penetrating cancer cell-targeting GFP is a highly potential nanocarrier for the treatment of brain tumors.

Short-time focused ultrasound hyperthermia enhances liposomal doxorubicin delivery and antitumor efficacy for brain metastasis of breast cancer.

The blood-brain/tumor barrier inhibits the uptake and accumulation of chemotherapeutic drugs. Hyperthermia can enhance the delivery of chemotherapeutic agent into tumors. In this study, we investigated the effects of short-time focused ultrasound (FUS) hyperthermia on the delivery and therapeutic efficacy of pegylated liposomal doxorubicin (PLD) for brain metastasis of breast cancer. Murine breast cancer 4T1-luc2 cells expressing firefly luciferase were injected into female BALB/c mice striatum tissues and used as a brain metastasis model. The mice were intravenously injected with PLD (5 mg/kg) with/without 10-minute transcranial FUS hyperthermia on day 6 after tumor implantation. The amounts of doxorubicin accumulated in the normal brain tissues and tumor tissues with/without FUS hyperthermia were measured using fluorometry. The tumor growth for the control, hyperthermia, PLD, and PLD + hyperthermia groups was measured using an IVIS spectrum system every other day from day 3 to day 11. Cell apoptosis and tumor characteristics were assessed using immunohistochemistry. Short-time FUS hyperthermia was able to significantly enhance the PLD delivery into brain tumors. The tumor growth was effectively inhibited by a single treatment of PLD + hyperthermia compared with both PLD alone and short-time FUS hyperthermia alone. Immunohistochemical examination further demonstrated the therapeutic efficacy of PLD plus short-time FUS hyperthermia for brain metastasis of breast cancer. The application of short-time FUS hyperthermia after nanodrug injection may be an effective approach to enhance nanodrug delivery and improve the treatment of metastatic cancers.

Polymersomes conjugated with des-octanoyl ghrelin for the delivery of therapeutic and imaging agents into brain tissues.

The effective protection of the blood-brain barrier (BBB) from tight junctions and efflux transport systems ultimately results in the limited entry of 95% of drug/gene candidates, which are potentially beneficial for central nervous system (CNS) diseases. In order to enhance the brain-specific delivery, in this study we developed a targeting carrier system, which consists of poly(carboxyl ethylene glycol-g-glutamate)-co-poly(distearin-g-glutamate) (CPEGGM-PDSGM) polymersomes with the conjugation of des-octanoyl ghrelin. Des-octanoyl ghrelin across the BBB was reported to be unidirectional (blood-to-brain direction). However, there is no report about the conjugation of des-octanoyl ghrelin to a drug carrier system to confer the BBB targeting property through des-octanoyl ghrelin binding sites mediated endocytosis. To qualitatively and quantitatively investigate this carrier's properties, coumarin 6, Cy5.5 and met-enkephalin were individually encapsulated in these polymersomes. The experimental results showed that the cellular uptake was significantly higher for des-octanoyl ghrelin-conjugated polymersomes (GPs) than unconjugated polymersomes when co-incubated with the BBB cells. In addition, an enhanced accumulation in brain together with a reduced accumulation in liver and spleen was observed in animal study, indicating better brain selectivity for the GPs. In a hot-plate test, a significant inhibition of nociceptive response could be achieved for an intravenous injection of GPs encapsulated with met-enkephalin. The overall results demonstrated that GPs own a great potential for targeting delivery of drug across the BBB to treat CNS diseases.

Modeling of a seated human body exposed to vertical vibrations in various automotive postures.

Although much research has been devoted to constructing specific models or to measuring the response characteristics of seated subjects, investigations on a mathematical human model on a seat with a backrest to evaluate vehicular riding comfort have not yet attracted the same level of attention. For the responses of a seated body to vertical vibrations, mathematical models of the mechanisms must be at least two-dimensional in the sagittal plane. In describing the motions of a seated body, two multibody models representative of the automotive postures found in the literature were investigated, one with and the other without a backrest support. Both models were modified to suitably represent the different automotive postures with and without backrest supports, and validated by various experimental data from the published literature pertaining to the same postural conditions. On the basis of the analytical study and the experimental validation, the fourteen-degrees-of-freedom model proposed in this research was found to be best fitted to the test results; therefore, this model is recommended for studying the biodynamic responses of a seated human body exposed to vertical vibrations in various automotive postures.