RESUMEN
Gene therapy is likely to be the most promising way to tackle cancer, while defects in molecular strategies and delivery systems have led to an impasse in clinical application. Here, it is found that onco-miRNAs of the miR-515 and -449 families were upregulated in hepatocellular carcinoma (HCC), and the sponge targeting miR-515 family had a significant probability to suppress cancer cell proliferation. Then, we constructed non-toxic sponge-loaded magnetic nanodroplets containing 20% C6F14 (SLMNDs-20%) that are incorporated with fluorinated superparamagnetic iron oxide nanoparticles enhancing external magnetism-assisted targeting and enabling a direct visualization of SLMNDs-20% distribution in vivo via magnetic resonance imaging monitoring. SLMNDs-20% could be vaporized by programmable focused ultrasound (FUS) activation, achieving â¼45% in vitro sponge delivery efficiency and significantly enhancing in vivo sponge delivery without a clear apoptosis. Moreover, the sponge-1-carrying SLMNDs-20% could effectively suppress proliferation of xenograft HCC after FUS exposure because sponge-1-suppressing onco-miR-515 enhanced the expression of anti-oncogenes (P21, CD22, TIMP1, NFKB, and E-cadherin) in cancer cells. The current results indicated that ultrasonic cavitation-inducing sonoporation enhanced the intracellular delivery of sponge-1 using SLMNDs-20% after magnetic-assisted accumulation, which was a therapeutic approach to inhibit HCC progression.
Asunto(s)
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Imanes/química , MicroARNs/química , MicroARNs/genética , Nanopartículas/química , Animales , Apoptosis/genética , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Proliferación Celular/fisiología , Regulación Neoplásica de la Expresión Génica/genética , Terapia Genética/métodos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Magnetismo/métodos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ultrasonografía/métodosRESUMEN
OBJECTIVES: The poor safety profile of sunitinib capsules has encouraged the identification of targeted drug delivery systems against renal cell carcinoma. This study aimed to explore the effect of sunitinib-loaded microbubbles along with ultrasound (US) treatment on proliferation and apoptosis of human GRC-1 granulocyte renal carcinoma cells in vitro and in vivo (xenograft tumor growth in nude mice). METHODS: Liposomes containing sunitinib were prepared by using the transmembrane ammonium sulfate gradient method and then absorbed into polymer microbubbles to generate sunitinib-loaded microbubbles. Entrapment of sunitinib was verified by 25-25-[N-[(7-nitro-2-1,3-benzoxadiazol-4-yl)methyl]amino]-27-norcholesterol staining. GRC-1 cells were treated with microbubbles alone, liposomes alone, sunitinib alone, sunitinib-loaded microbubbles without and with US, and no treatment (control). Cell survival and apoptosis were assessed at 12, 24, and 48 hours after treatment. Xenograft tumors were induced by implantation of GRC-1 cells in nude mice. The animals with tumors were then randomly assigned to sunitinib alone, sunitinib-loaded microbubbles - US, sunitinib-loaded microbubbles + US, and no treatment (control; n = 10 per group). The tumor volumes were analyzed on the 7th, 15th, and 21st days. RESULTS: The sunitinib entrapment efficiency in the liposomes was approximately 78%. The effective sunitinib concentration in each group was 0.1 µg/mL. The sunitinib-loaded microbubble + US group showed a lower in vitro cell survival rate (P < .001) compared with the other groups. Greater in vivo inhibition of xenograft tumor growth was also observed in the sunitinib-loaded microbubble + US group compared with the other groups. CONCLUSIONS: Combined sunitinib-loaded microbubbles and US treatment significantly inhibits growth of renal carcinoma cells both in vitro and in vivo.
Asunto(s)
Carcinoma de Células Renales/patología , Carcinoma de Células Renales/terapia , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Indoles/administración & dosificación , Neoplasias Renales/patología , Neoplasias Renales/terapia , Pirroles/administración & dosificación , Animales , Antineoplásicos/administración & dosificación , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/efectos de la radiación , Terapia Combinada/métodos , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/efectos de la radiación , Sinergismo Farmacológico , Femenino , Ondas de Choque de Alta Energía , Liposomas/química , Liposomas/efectos de la radiación , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Microburbujas , SunitinibRESUMEN
Bimodal imaging offers additional imaging signal thus finds wide spread application in clinical diagnostic imaging. Fluorescence/ultrasound bimodal imaging contrast agent using fluorescent dyes or quantum dots for fluorescence signal has emerged as a promising method, which however requires visible light or UV irradiation resulting in photobleaching, photo blinking,auto-fluorescence and limited tissue penetration depth. To surmount these problems, we developed a novel bimodal contrast agent using layer-by-layer assembly of up conversion nanoparticles onto the surface of microbubbles. The resulting microbubbles with average size of 2 µm provide enhanced ultrasound echo for ultrasound imaging and upconversion emission upon near infrared irradiation for fluorescence imaging. The developed bimodal contrast agent holds great potential to be applied in ultrasound target technique for targeted diseases diagnostics and therapy.
Asunto(s)
Medios de Contraste/química , Microburbujas , Nanopartículas/química , Imagen Óptica/instrumentación , Ultrasonografía/instrumentación , Nanopartículas/ultraestructura , Tamaño de la Partícula , Espectrometría de Fluorescencia , Propiedades de SuperficieRESUMEN
Phase-change nanodroplets (PCNDs) are customizable and controllable theranostic agents of particular interest in extravascular therapies such as drug delivery and histotripsy. High-bulk-boiling-point (HBP) PCNDs are preferred for their enhanced thermal stability under physiological temperature to achieve on-demand therapeutic effects on target sites - mainly in tumor tissue. However, the behavioral patterns of high-concentration, heterogeneously distributed HBP PCNDs in vivo have rarely been explored - the foci of PCNDs-related therapies mostly fall on the final therapeutic effect rather than the detailed behaviors of PCNDs, which may hamper the development and improvement of in vivo treatments with PCNDs. To fill the gap, we demonstrate an ultrasound-only extravascular monitoring technique to analyze the underlying behavioral patterns of intratumorally-injected HBP PCNDs. In our hypothesis, recondensation and coalescence are the two predominant patterns influencing the trend of the post-activation signal of PCNDs. A "blink map" method was thus proposed to separate the two parts of the signal by recognizing the unique signal pattern of stochastic recondensation, and four derivative metrics were calculated for further analysis. The results revealed the post-activation patterns of PCNDs at different activation-pulse durations and activation stages throughout the activation-imaging period, and several general trends were observed and explained by existing theories, suggesting the feasibility of our extravascular monitoring technique. Overall, this work enriches the knowledge of the characteristics of HBP PCNDs as extravascular theranostic agents, and the monitoring results have the potential to provide timely feedback on PCNDs-related treatments underway, which may help adjust the treatment strategy and improve the therapeutic efficacy.
RESUMEN
Accurate and real-time separation of blood signal from clutter and noise signals is a critical step in clinical non-contrast ultrasound microvascular imaging. Despite the widespread adoption of singular value decomposition (SVD) and robust principal component analysis (RPCA) for clutter filtering and noise suppression, the SVD's sensitivity to threshold selection, along with the RPCA's limitations in undersampling conditions and heavy computational burden often result in suboptimal performance in complex clinical applications. To address those challenges, this study presents a novel low-rank prior-based fast RPCA (LP-fRPCA) approach to enhance the adaptability and robustness of clutter filtering and noise suppression with reduced computational cost. A low-rank prior constraint is integrated into the non-convex RPCA model to achieve a robust and efficient approximation of clutter subspace, while an accelerated alternating projection iterative algorithm is developed to improve convergence speed and computational efficiency. The performance of the LP-fRPCA method was evaluated against SVD with a tissue/blood threshold (SVD1), SVD with both tissue/blood and blood/noise thresholds (SVD2), and the classical RPCA based on the alternating direction method of multipliers algorithm through phantom and in vivo non-contrast experiments on rabbit kidneys. In the slow flow phantom experiment of 0.2 mm/s, LP-fRPCA achieved an average increase in contrast ratio (CR) of 10.68 dB, 9.37 dB, and 8.66 dB compared to SVD1, SVD2, and RPCA, respectively. In the in vivo rabbit kidney experiment, the power Doppler results demonstrate that the LP-fRPCA method achieved a superior balance in the trade-off between insufficient clutter filtering and excessive suppression of blood flow. Additionally, LP-fRPCA significantly reduced the runtime of RPCA by up to 94-fold. Consequently, the LP-fRPCA method promises to be a potential tool for clinical non-contrast ultrasound microvascular imaging.
Asunto(s)
Algoritmos , Microvasos , Ultrasonografía , Animales , Conejos , Ultrasonografía/métodos , Microvasos/diagnóstico por imagen , Fantasmas de Imagen , Relación Señal-Ruido , Análisis de Componente Principal , Procesamiento de Imagen Asistido por Computador/métodos , Riñón/diagnóstico por imagen , Riñón/irrigación sanguíneaRESUMEN
Fractional flow has been proposed for quantifying the degree of functional stenosis in cerebral arteries. Herein, subharmonic aided pressure estimation (SHAPE) combined with plane wave (PW) transmission was employed to noninvasively estimate the pressure distribution and fractional flow in the middle cerebral artery (MCA) in vitro. Consequently, the effects of incident sound pressure (peak negative pressures of 86-653 kPa), pulse repetition frequency (PRF), number of pulses, and blood flow rate on the subharmonic pressure relationship were investigated. The radio frequency data were stored and beamformed offline, and the subharmonic amplitude over a 0.4 MHz bandwidth was extracted using a 12-cycle PW at 4 MHz. The optimal incident sound pressure was 217 kPa without skull (sensitivity = 0.09 dB/mmHg; r2 = 0.997) and 410 kPa with skull (median sensitivity = 0.06 dB/mmHg; median r2 = 0.981). The optimal PRF was 500 Hz, as this value affords the highest sensitivity (0.09 dB/mmHg; r2 = 0.976) and temporal resolution. In addition, the blood flow rate exhibited a lesser effect on the subharmonic pressure relationship in our experimental setup. Using the optimized parameters, the blood pressure distribution and fractional flow (FFs) were measured. As such, the FFs value was in high agreement with the value measured using the pressure sensor (FFm). The mean ± standard deviations of the FF difference (FFm - FFs) were 0.03 ± 0.06 without skull and 0.01 ± 0.05 with skull.
Asunto(s)
Microburbujas , Arteria Cerebral Media , Arteria Cerebral Media/diagnóstico por imagen , Fantasmas de Imagen , Medios de Contraste , UltrasonografíaRESUMEN
Based on the diameter and position information of small vessels obtained by transcranial super-resolution imaging using 3 MHz low-frequency chirp plane waves, a Gaussian-like non-linear compression was adopted to compress the blood flow signals in spatiotemporal filtering (STF) data to a precise region, and then estimate the blood flow velocity field inside the region over the adjacent time intervals using ultrasound imaging velocimetry (UIV). Imaging parameters, such as the mechanical index (MI), frame rate, and microbubble (MB) concentration, are critical during the estimation of velocity fields over a short time at high MB contrast agent concentrations. These were optimized through experiments and algorithms, in which dividing the connected domain was proposed to calculate MB cluster spot centroid spacing (SCS) and the spot-to-flow area ratio (SFAR) to determine the suitable MB concentration. The results of the in vitro experiments showed that the estimation of the small vessel flow velocity field was consistent with the theoretical results; the velocity field resolution for vessels with diameters of 0.5 mm and 0.3 mm was 36 µm and 21 µm, and the error between the mean velocity and the theoretical value was 0.7 % and 0.67 %, respectively.
Asunto(s)
Medios de Contraste , Microburbujas , Ultrasonografía/métodos , Reología/métodos , Velocidad del Flujo Sanguíneo/fisiología , Fantasmas de ImagenRESUMEN
Understanding the behavior of nanodroplets converted into microbubbles with applied ultrasound is an important problem in tumor therapeutical and diagnostic applications. In this study, a comprehensive model is proposed to investigate the vaporization process and the direct growth threshold of the nanodroplet by following the vapor bubble growth, especially attention devoted to the effect of tissue viscoelasticity and adjacent phase-changed microbubbles (PCMBs). It is shown that the ultrasonic energy must be sufficiently strong to counterbalance the natural condensation of the vapor bubble and the tissue stiffness-inhibitory effect. The softer tissue with a lower shear modulus favors the vaporization process, and the nanodroplet has a lower direct growth threshold in the softer tissue. Moreover, the adjacent PCMBs show a suppression effect on the vaporization process due to the negative value of the secondary Bjerknes force, implying an attractive force, preventing the nanodroplet from escaping from the constraint of the adjacent PCMBs. However, according to the linear scattering theory, the attractive force signifies that the constraint is weak, causing the direct growth threshold to increase in the range of 0.09-0.24 MPa. The weak increase in threshold demonstrates that the direct growth threshold is relatively unaffected by the adjacent PCMBs. The prediction results of our model are in good agreement with the experiment results obtained by the echo enhancement method, in which the threshold is relatively independent of the intermediate concentration. The findings presented here provide physical insight that will be further helpful in understanding the complex behavior of the nanodroplet responses to ultrasound in practical medical applications.
Asunto(s)
Microburbujas , Ultrasonido , Volatilización , 4-Cloromercuribencenosulfonato , Ultrasonografía , Medios de ContrasteRESUMEN
The dCas9-based CRISPR interference (CRISPRi) system efficiently silences genes without causing detectable off-target activity, thus showing great potential for the treatment of cancer at the transcriptional level. However, due to the large size of the commonly used CRISPRi system, effective delivery of the system has been a challenge that hinders its application in the clinic. Herein, a combination of pH-responsive lipid-polymer hybrid nanoparticles (PLPNs) and ultrasound-mediated microbubble destruction (UMMD) is used for the delivery of the CRISPRi system. The core-shell structure of PLPNs can effectively be loaded with the CRISPRi plasmid, and increases the time spent in the circulating in vivo, and "actively target" cancer cells. Moreover, the combination of PLPNs with UMMD achieves a higher cellular uptake of the CRISPRi plasmid in vitro and retention in vivo. Furthermore, when PLPNs loaded with a CRISPRi plasmid that targets microRNA-10b (miR-10b) are used in combination with UMMD, it results in the effective repression of miR-10b in breast cancer, simultaneous disturbance of multiple cell migration and invasion-related signaling pathways, and a significant inhibition of lung metastasis. Thus, the established system presents a versatile, highly efficient, and safe strategy for delivery of the CRISPRi system both in vitro and in vivo.
Asunto(s)
MicroARNs , Nanopartículas , Neoplasias , Humanos , Sistemas CRISPR-Cas , Polímeros , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Microburbujas , Neoplasias/genética , LípidosRESUMEN
Sonodynamic therapy (SDT) as an auxiliary modality of cancer immunotherapy enhances systemic anti-tumor immunity. However, the efficiency of SDT-mediated immunotherapy based on conventional focused ultrasound (FUS) is restricted by the tiny focal region of FUS. Focused acoustic vortex (FAV) possessing a larger focal region, can induce stronger cavitation and thermal effects than FUS with the same parameters, having the potential to overcome this issue. This research investigated the feasibility of FAV-mediated sonochemotherapy combined with the immune checkpoint blockade (ICB) to reshape immunosuppressive tumor microenvironment (TME), inhibit tumor growth and lung metastasis. Sonosensitizer chlorin e6 (Ce6) and chemotherapeutic agent doxorubicin (Dox) were co-loaded into microbubble-liposome complex to compose Ce6/Dox@Lip@MBs (CDLM) for "all-in-one" synergistic sonochemotherapy, whose main components were clinical approved. FAV-activated CDLM significantly enriched immunogenic cell death (ICD) inducers in tumors and amplified ICD of cancer cells compared with FUS-activated CDLM. Furthermore, the amplified-ICD combined with ICB increased the infiltration of cytotoxic T lymphocytes and natural killer cells, polarized M2 macrophages to M1 macrophages, and decreased regulatory T cells. This study provides a multifunctional strategy for enriching ICD inducers in tumors and amplifying ICD to ameliorate immunosuppressive TME and potentiate systemic anti-tumor immunity.
Asunto(s)
Muerte Celular Inmunogénica , Neoplasias , Inmunoterapia , Doxorrubicina , Acústica , Inmunosupresores , Neoplasias/terapiaRESUMEN
Objective. Contrast-free microvascular imaging is clinically valuable for the assessment of physiological status and the early diagnosis of diseases. Effective clutter filtering is essential for microvascular visualization without contrast enhancement. Singular value decomposition (SVD)-based spatiotemporal filter has been widely used to suppress clutter. However, clinical real-time imaging relies on short ensembles (dozens of frames), which limits the implementation of SVD filtering due to the large error of eigen-correlated estimations and high dependence on optimal threshold when used in such ensembles.Approach. To address the above challenges of imaging in short ensembles, two optimized filters of angular domain data are proposed in this paper: grouped angle SVD (GA-SVD) and angular-coherence-based higher-order SVD (AC-HOSVD). GA-SVD applies SVD to the concatenation of all angular data to improve clutter rejection performance in short ensembles, while AC-HOSVD applies HOSVD to the angular data tensor and utilizes angular coherence in addition to spatial and temporal features for filtering. Feasible threshold selection strategies in each feature space are provided. The clutter rejection performance of the proposed filters and SVD was evaluated with Doppler phantom andin vivostudies at different cases. Moreover, the robustness of the filters was explored under wrong singular value threshold estimation, and their computational complexity was studied.Main results. Qualitative and quantitative results indicated that GA-SVD and AC-HOSVD can effectively improve clutter rejection performance in short ensembles, especially AC-HOSVD. Notably, the proposed methods using 20 frames had similar image quality to SVD using 100 frames.In vivostudies showed that compared to SVD, GA-SVD increased the signal-to-noise-ratio (SNR) by 6.03 dB on average, and AC-HOSVD increased the SNR by 8.93 dB on average. Furthermore, AC-HOSVD remained better power Doppler image quality under non-optimal thresholds, followed by GA-SVD.Significance. The proposed filters can greatly enhance contrast-free microvascular visualization in short ensembles and have potential for different clinical translations due to the performance differences.
Asunto(s)
Procesamiento de Imagen Asistido por Computador , Procesamiento de Señales Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Ultrasonografía Doppler/métodos , Fantasmas de Imagen , Relación Señal-Ruido , Ultrasonografía/métodos , Velocidad del Flujo Sanguíneo/fisiologíaRESUMEN
This paper compares the efficiency of flowing polymer- and lipid-shelled microbubbles (MBs) in the heating and cavitation during focused ultrasound exposures. Temperature and cavitation activity were simultaneously measured as the two types of shelled MBs and saline flowing through a 3 mm diameter vessel in the phantom with varying flow velocities (0-20 cm/s) at different acoustic power levels (0.6-20 W) with each exposure for 5 s. Temperature and cavitation for the lipid-shelled MBs were higher than those for the polymer-shelled MBs. Temperature rise decreased with increasing flow velocities for the two types of shelled MBs and saline at acoustic power 1.5 W. At acoustic power 11.1 W, temperature rise increased with increasing flow velocities for the lipid-shelled MBs. For the polymer-shelled MBs, the temperature rise increased with increasing flow velocities from 3-15 cm/s and decreased at 20 cm/s. Cavitation increased with increasing flow velocity for the two shelled MBs and there were no significant changes of cavitation with increasing flow velocities for saline. These results suggested that lipid-shelled MBs may have a greater efficiency than polymer-shelled MBs in heating and cavitation during focused ultrasound exposures.
Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Calor , Ácido Láctico , Microburbujas , Fosfolípidos , Ácido Poliglicólico , Hexafluoruro de Azufre , Fantasmas de Imagen , Copolímero de Ácido Poliláctico-Ácido PoliglicólicoRESUMEN
Intracranial blood pressure can directly reflect the status of blood vessels in real time. However, it can only be estimated invasively using a microcatheter during craniotomy. Subharmonic-aided pressure estimation (SHAPE) is a promising technique for estimating cardiac pressures but mainly uses Sonazoid, whereas SHAPE using SonoVue is still in the early stages of development. The aim of this study was to optimize transcranial SHAPE using SonoVue by investigating the relationship between subharmonic signals and middle cerebral artery pressure (MCAP) (20-160 mmHg) in vitro. We examined the effect of acoustic output levels (peak negative pressures (PNPs) of 238, 346, and 454 kPa), time in suspension (time from reconstituting the suspension to extracting it: 0-30 min), and exposure to gas-equilibrated saline (3 min, 1 h, or original gas completely replaced by air) on the subharmonic-pressure relationship. A mean subharmonic amplitude over a 0.4 MHz bandwidth was extracted using a 5 MHz 12-cycle pulse. A PNP of 346 kPa elicited the best subharmonic sensitivity for assessing hydrostatic pressures up to 0.24 dB/mmHg, possibly because compression-only behavior no longer occurs at this pressure. Moreover, the expansion force is not large enough to offset the effects of hydrostatic pressure. A linear monotonic relationship between the subharmonic amplitude and hydrostatic pressure was only observed for just prepared SonoVue. Excessive exposure to gas-equilibrated saline also affected the subharmonic-pressure relationship. Therefore, just prepared SonoVue should be used, and the duration of the pressure estimation process should be strictly controlled.
Asunto(s)
Medios de Contraste , Hexafluoruro de Azufre , Presión Sanguínea , Microburbujas , Fosfolípidos , Ultrasonografía/métodosRESUMEN
Ferroptosis is an emerging form of programmed cell death, and its combination with sonodynamic therapy (SDT) for anti-tumor activity is gradually attracting attention. However, their application against gliomas has not been studied. Herein, multifunctional cancer homologous targeting biomimetic nanoparticles (PIOC@CM NPs) encapsulating both Fe3O4 and Ce6 were constructed as a nanosonosensitizer. Based on focused ultrasound (US) combined with circulating microbubbles (MBs) to open the blood-brain barrier (BBB) in a safe and transient manner, the development of a therapeutic strategy to integrate the biomimetic nanosonosensitizer-mediated SDT and ferroptosis could achieve synergistic therapeutic effects against gliomas. We demonstrated that the glioma C6 cell membrane (CM) on the surface of the NPs allowed the nanosonosensitizer to accumulate selectively in tumors through homologous targeting in vitro. After efficient internalization in C6 cells, the PIOC@CM NPs could significantly increase the level of reactive oxygen species (ROS) and deplete glutathione (GSH) upon ultrasonic irradiation, resulting in the loss of glutathione peroxidase-4 (GPX4) activity, which facilitated SDT and ferroptosis to kill glioma C6 cells. Furthermore, the PIOC@CM NPs were intravenously injected after noninvasively opening the BBB via US-MBs, which enhanced the accumulation of the nanosonosensitizer in tumor tissues. Crucially, an attractive phenomenon of the significant reduction in orthotopic gliomas after the second US pulse-triggered SDT and ferroptosis was observed. Taken together, this study presents a novel combinatorial glioma therapeutic strategy based on noninvasive BBB opening with a biomimetic sonotheranostic system-mediated SDT and ferroptosis.
Asunto(s)
Ferroptosis , Glioma , Nanopartículas , Terapia por Ultrasonido , Biomimética , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Glioma/patología , Humanos , Nanopartículas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Terapia por Ultrasonido/métodosRESUMEN
The combination of checkpoint blockade with focused ultrasound (FUS) physical therapy can enhance antitumor immune response by improving the precision and efficiency of immunotherapy. However, one of the major disadvantages of conventional FUS treatment is the small lesion size, which prolongs treatment duration. We constructed a focused acoustic vortex (FAV) system with a hollow cylindrical focal region, which exhibited a larger focal region compared to conventional FUS of the same frequency. We developed an all-in-one synergistic therapy against metastatic breast cancer based on integrated FAV double combination sequence-regulated phase-transformation nanodroplets (CPDA@PFH) with checkpoint blockade immunotherapy. A single treatment with FAV + CPDA@PFH resulted in 2.25-fold higher inhibition of tumor growth compared to that with FUS + CPDA@PFH. In addition, FAV-regulated CPDA@PFH combined with ICB induced a systemic immune response that not only inhibited the growth of primary (98.41% inhibition rate) and distal (80.71%) 4T1 tumors but also reduced the progression of lung metastasis. In addition, the synergistic therapy achieved long-term immune memory that effectively prevented tumor growth and improved the survival time of mice. The long-term survival rate of 4T1 tumor-bearing mice treated with FAV + CPDA@PFH + Anti-PD-L1 was 57.14% on day 60 after treatment. Our study is a proof-of-concept of cascade-amplified synergistic tumor therapeutics based on ultrasonic-hyperthermia, cavitation, sonodynamic therapy (SDT), and checkpoint blockade immunotherapy through FAV-regulated CPDA@PFH phase-transformation nanodroplets.
Asunto(s)
Hipertermia Inducida , Neoplasias , Acústica , Animales , Línea Celular Tumoral , Hipertermia Inducida/métodos , Inhibidores de Puntos de Control Inmunológico , Inmunoterapia/métodos , Ratones , Neoplasias/patologíaRESUMEN
Retraction of 'Enhanced anti-tumor efficacy of hyaluronic acid modified nanocomposites combined with sonochemotherapy against subcutaneous and metastatic breast tumors' by Pengying Wu et al., Nanoscale, 2019, 11, 11470-11483, https://doi.org/10.1039/C9NR01691K.
RESUMEN
Background: Ultrasound is ideal for displaying intracranial great vessels but not intracranial microvessels and terminal vessels. Even with contrast agents, the imaging effect is still unsatisfactory. In recent years, significant theoretical advances have been achieved in super-resolution imaging. The latest commonly used ultrafast plane-wave ultrasound Doppler imaging of the brain and microbubble-based super-resolution ultrasound imaging have been applied to the imaging of cerebral microvessels and blood flow in small animals such as mice but have not been applied to in vivo imaging of the cerebral microvessels in monkeys and larger animals. In China, preliminary research results have been obtained using super-resolution imaging in certain fields but rarely in fundamental and clinical experiments on large animals. In recent years, we have conducted a joint study with the Xi'an Jiaotong University to explore the application and performance of this new technique in the diagnosis of cerebrovascular diseases in large animals. Objective: To explore the characteristics and advantages of microbubble-based super-resolution ultrasound imaging of intracranial vessels in rhesus monkeys compared with conventional transcranial ultrasound. Methods: First, the effectiveness and feasibility of the super-resolution imaging technique were verified by modular simulation experiments. Then, the imaging parameters were adjusted based on in vitro experiments. Finally, two rhesus monkeys were used for in vivo experiments of intracranial microvessel imaging. Results: Compared with conventional plane-wave imaging, super-resolution imaging could measure the inner diameters of cerebral microvessels at a resolution of 1 mm or even 0.7 mm and extract blood flow information. In addition, it has a better signal-to-noise ratio (5.625 dB higher) and higher resolution (~30-fold higher). The results of the experiments with rhesus monkeys showed that microbubble-based super-resolution ultrasound imaging can achieve an optimal resolution at the micron level and an imaging depth >35 mm. Conclusion: Super-resolution imaging can realize the monitoring imaging of high-resolution and fast calculation of microbubbles in the process of tissue damage, providing an important experimental basis for the clinical application of non-invasive transcranial ultrasound.
RESUMEN
High-intensity focused ultrasound (HIFU) has been widely used in tumor ablation in clinical settings. Meanwhile, there is great potential to increase the therapeutic efficiency of temporary cavitation due to enhanced thermal effects and combined mechanical effects from nonlinear vibration and collapse of the microbubbles. In this study, dual-frequency (1.1 and 5 MHz) HIFU was used to produce acoustic droplet vaporization (ADV) microbubbles from activatable perfluoropentane-loaded polymer nanoparticles (PFP@Polymer NPs), which increased the therapeutic outcome of the HIFU and helped realize tumor theranostics with ultrasound contrast imaging. Combined with PFP@Polymer NPs, dual-frequency HIFU changed the shape of the damage lesion and reduced the acoustic intensity threshold of thermal damage significantly, from 216.86 to 62.38 W/cm2. It produced a nearly 20 °C temperature increase in half the irradiation time and exhibited a higher tumor inhibition rate (84.5% ± 3.4%) at a low acoustic intensity (1.1 MHz: 23.77 W/cm2; 5 MHz: 0.35 W/cm2) in vitro than the single-frequency HIFU (60.2% ± 11.9%). Moreover, compared with the traditional PFP@BSA NDs, PFP@Polymer NPs showed higher anti-tumor efficacy (81.13% vs. 69.34%; * p < 0.05) and better contrast-enhanced ultrasound (CEUS) imaging ability (gray value of 57.53 vs. 30.67; **** p < 0.0001), probably benefitting from its uniform and stable structure. It showed potential as a highly efficient tumor theranostics approach based on dual-frequency HIFU and activatable PFP@Polymer NPs.
RESUMEN
The PIK3 CA gene encodes the p110α protein subunit and is one of the most efficient cancer genes in solid and hematological tumors including hepatocellular carcinoma (HCC). There are currently ongoing therapies against tumors based on PIK3 CA inhibition. Because microRNAs (miRNAs) play an important role in post-transcriptional regulation and are also involved in the inhibition of PIK3 CA expression to suppress cancer cell proliferation, overexpression of tumor-suppressive miRNA is a promising therapeutic approach for HCC therapy. The successful and localized delivery of miRNA overexpression vectors (pre-miRNA plasmids) is very important in improving the therapeutic efficacy of this miRNA therapy strategy. In the study described here, submicron acoustic phase-shifted nanodroplets were used to efficiently deliver pre-miRNA plasmid in vitro and in vivo for HCC therapy under focused ultrasound (US) activation. Briefly, six miRNAs, inhibiting PIK3 CA and downregulated in HCC, were selected through summary and analysis of the currently existing literature data. Quantitative real-time polymerase chain reaction (qRT-PCR), Western blot and cell apoptosis assay revealed that pre-miR-139, -203a, -378a and -422a plasmids among the six miRNA overexpression vectors could suppress growth of the hepatoma cell line SMMC-7721. These four pre-miRNA plasmids were then electrostatically adhered to positively charged lipid-shelled nanodroplets to obtain plasmid-loaded nanodroplets (PLNDs). The PLND-generated microbubbles oscillated and even collapsed under US exposure to release the loaded pre-miRNA plasmids and enhance their cellular uptake through consequent sonoporation, that is, formation of small pores on the cell membrane induced by the mechanical effects of PLND cavitation. Fluorescence microscopy results revealed that PLNDs could effectively deliver the aforementioned four pre-miRNA plasmids into SMMC-7721 cells in vitro under 1.2-MHz 60-cycle sinusoid US exposure with a peak negative pressure >5.5 MPa at a 40-Hz pulse repetition frequency. Plasmid delivery efficiency and cell viability positively correlated with the inertial cavitation dose that was determined mainly by peak negative pressure. Furthermore, PLNDs combined with US were evaluated in vivo to deliver these four pre-miRNAs plasmids and verify their therapeutic efficacy in subcutaneous tumor of the mouse xenograft HCC model. The results revealed that the PLNDs loaded with pre-miR-139 and -378a plasmids could effectively suppress tumor growth after US treatment. Thus, combination of pre-miRNA PLNDs with US activation seems to constitute a potential strategy for HCC therapy.
Asunto(s)
Carcinoma Hepatocelular/terapia , Terapia Genética/métodos , Neoplasias Hepáticas/terapia , MicroARNs , Nanoestructuras , Plásmidos , Animales , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Células Tumorales Cultivadas , UltrasonografíaRESUMEN
This work investigated and compared the dynamic cavitation characteristics between low and high boiling-point phase-shift nanodroplets (NDs) under physiologically relevant flow conditions during focused ultrasound (FUS) exposures at different peak rarefactional pressures. A passive cavitation detection (PCD) system was used to monitor cavitation activity during FUS exposure at various acoustic pressure levels. Root mean square (RMS) amplitudes of broadband noise, spectrograms of the passive cavitation detection signals, and normalized inertial cavitation dose (ICD) values were calculated. Cavitation activity of low-boiling-point perfluoropentane (PFP) NDs and high boiling-point perfluorohexane (PFH) NDs flowing at in vitro mean velocities of 0-15 cm/s were compared in a 4-mm diameter wall-less vessel in a transparent tissue-mimicking phantom. In the static state, both types of phase-shift NDs exhibit a sharp rise in cavitation intensity during initial FUS exposure. Under flow conditions, cavitation activity of the PFH NDs reached the steady state less rapidly compared to PFP NDs under the lower acoustic pressure (1.35 MPa); at the higher acoustic pressure (1.65 MPa), the RMS amplitude increased more sharply during the initial FUS exposure period. In particular, the RMS-time curves of the PFP NDs shifted upward as the mean flow velocity increased from 0 to 15 cm/s; the RMS amplitude of the PFH ND solution increased from 0 to 10 cm/s and decreased at 15 cm/s. Moreover, amplitudes of the echo signal for the low boiling-point PFP NDs were higher compared to the high boiling-point PFH NDs in the lower frequency range, whereas the inverse occurred in the higher frequency range. Both PFP and PFH NDs showed increased cavitation activity in the higher frequency under the flow condition compared to the static state, especially PFH NDs. At 1.65 MPa, normalized ICD values for PFH increased from 0.93 ± 0.03 to 0.96 ± 0.04 and from 0 to 10 cm/s, then decreased to 0.86 ± 0.05 at 15 cm/s. This work contributes to our further understanding of cavitation characteristics of phase-shift NDs under physiologically relevant flow conditions during FUS exposure. In addition, the results provide a reference for selecting suitable phase-shift NDs to enhance the efficiency of cavitation-mediated ultrasonic applications.