Advances in Ultrasound-Responsive Radiopharmaceutical Systems for the Management of Ocular Malignancies.

Background Ocular melanoma is a malignant tumor with a poor prognosis.To study its mode of pathogenesis and development is helpful for early diagnosis and treatment and improving prognosis. Objective This study was to analyze the location and pathological types of ocular melanoma,and explore the relationship of pathological types with prognosis of ocular malignant melanoma. Methods 110 clinical data and specimens of ocular melanoma were collected at West China Hospital,China.The specimens were examined by hematoxylin & eosin staining,immunochemistry and studying their ultrastructure.The growth location,histological classification,and their relationship with prognosis were analyzed and discussed.The clinicopathological records of the 1 l0 cases with ocular region malignant melanoma treated from January 1980 to December 2007 were analyzed. Results The primary locations of the tumors with respect to the tissue type were:66 cases in the uvea (60.00％ ),27 cases in the ocular surface tissue (24.55％),8 cases in the secondary lesion of orbit cavity (7.27％),7 cases on the eyelid skin (6.36％),and 2 cases in the lacrimal sac ( 1.82％ ).The neoplasm was classified according to pathological types:spindle-cell A type in 31 cases (28.18％ ),spindle-cell B type in 31 cases (28.18％),mixed-cell type in 25 cases (22.73％),epithelioid-cell type in 17 cases ( 15.46％ ) and other type in 6 cases (5.45％).The notability of diffusion or recurrence rate of the 5 pathological types showed statistical significance (x2 =14.463,P =0.006 ),and the rank in decending order was:other type,epithelioid-cell type,mixed-cell type,spindle-cell B type and spindle-cell A type.The clinical manifestations of ocular melanoma were dependent upon the lesion position without specificity.Conclusions The majority of the ocular malignant melanoma appears in the uvea and ocular surface tissue,and its common pathological types were spindle-cell type followed by mixed-cell type,epithelioid-cell type and other type.The highest recurrence rate is in other type of ocular malignant melanoma.Ophthalmologist should be aware of the clinical manifestation of ocular malignant melanoma. Key words: Neoplasm; Ophthalmology; Malignant melanoma/symptom, classification, prognosis; Pathology/immunochemistry, ultrastructure

Simple SummaryVarious nanoparticles have been developed over the last few decades for targeted drug delivery to cancerous tumors while reducing toxicities. Thermosensitive liposomes (TSL) belong to the category of triggered nanoparticle delivery systems, where drug release occurs in response to hyperthermic temperatures (typically, >40 ºC). After administration, the TSL-encapsulated drug circulates for extended duration (hours) in the blood stream. Localized hyperthermia of the targeted tissue results in localized drug release, enabling up to 25x tumor drug uptake compared to administration of unencapsulated drug. Here, we review the delivery kinetics of TSL and discuss how the interaction between drug, TSL and hyperthermia device affects drug delivery. Thus, this review provides guidelines on how to improve drug delivery by optimizing the combination of TSL, drug, and hyperthermia method. Many of the concepts discussed are applicable to a variety of other triggered nanoparticle delivery systems.Thermosensitive liposomes (TSL) are triggered nanoparticles that release the encapsulated drug in response to hyperthermia. Combined with localized hyperthermia, TSL enabled loco-regional drug delivery to tumors with reduced systemic toxicities. More recent TSL formulations are based on intravascular triggered release, where drug release occurs within the microvasculature. Thus, this delivery strategy does not require enhanced permeability and retention (EPR). Compared to traditional nanoparticle drug delivery systems based on EPR with passive or active tumor targeting (typically <5%ID/g tumor), TSL can achieve superior tumor drug uptake (>10%ID/g tumor). Numerous TSL formulations have been combined with various drugs and hyperthermia devices in preclinical and clinical studies over the last four decades. Here, we review how the properties of TSL dictate delivery and discuss the advantages of rapid drug release from TSL. We show the benefits of selecting a drug with rapid extraction by tissue, and with quick cellular uptake. Furthermore, the optimal characteristics of hyperthermia devices are reviewed, and impact of tumor biology and cancer cell characteristics are discussed. Thus, this review provides guidelines on how to improve drug delivery with TSL by optimizing the combination of TSL, drug, and hyperthermia method. Many of the concepts discussed are applicable to a variety of other triggered drug delivery systems.

Tumor specific drug delivery has become increasingly interesting in cancer therapy. Using Mild local hyperthermia for tumor-specific drug release with thermosensitive liposomes, has a significant advantage over other triggering concepts in that the liposome tumor accumulation is increased as a consequence of increased tumor blood flow and in creased microvascular permeability. A crucial problem in this modality is how to generate a conformal and comparatively uniform temperature field for drug release. A new modality of drug targeting of tumors, which is based on thermosensitive liposomes, followed by localized release at the tumor site triggered by heating from ultrasound phased arrays, is currently under development. Besides noninvasiveness and deep penetration, an important advantage of ultrasound phased arrays is that they are able to generate multiple foci or switch between various multi-focus patterns and may produce a conformal and comparatively uniform temperature field. Pilot study on a conformal and comparatively uniform temperature field generation using ultrasound phased arrays was done. Primary simulation results show that employing combinations of different multi-focus patterns, we can obtain comparatively uniform, cylindrical temperature fields with diameters from 1 cm to 5cm and heights of 1cm.

Uveal Malignant Melanoma Associated with Ocular and Oculodermal Melanocytosis

A UV-related risk analysis in ophthalmic malignancies: Increased UV exposure may cause ocular malignancies

Objective: To investigate the main indications and prognosis of patients undergoing orbital exenteration (OE). Methods: It was a retrospective case series study. The medical records were collected of patients who underwent OE surgery at Beijing Tongren Hospital from January 2007 to December 2021, and their general information, tumor characteristics, lymph node metastasis, diagnosis and treatment, specific surgical techniques, pathological diagnosis and prognosis were analyzed. Kaplan-Meier survival curves were used to evaluate overall survival and recurrence-free survival. Results: A total of 147 patients were included, with a median age of 58 (48, 68) years. Among them, 82 patients (55.8%) were male and 65 (44.2%) were female, and all underwent unilateral OE. Five patients (3.4%) had benign lesions. Among the 142 patients with malignant tumors, conjunctival malignancies (37.3%) were the most common, followed by eyelid (29.6%), orbital (19.0%), and ocular (14.1%) malignancies. Among the 53 patients with conjunctival tumors, 38 (71.7%) had conjunctival melanoma and 14 (26.4%) had squamous cell carcinoma. Among the 42 patients with eyelid malignancies, 19 (45.2%) had sebaceous gland carcinoma and 16 (38.1%) had basal cell carcinoma. Among the 20 patients with ocular malignancies, 10 (50.0%) had choroidal melanoma and 9 (45.0%) had retinoblastoma. The most common pathological types among the 142 patients with malignant tumors were melanoma (51 cases, 35.9%), squamous cell carcinoma (20 cases, 14.1%), sebaceous gland carcinoma (19 cases, 13.4%), and basal cell carcinoma (16 cases, 11.3%). Of the 135 patients included in the survival analysis, all 5 patients with benign lesions were alive at the last follow-up. The median follow-up time for the 130 patients with malignant tumors was 6.9 (2.5, 6.9) years, ranging from 0.2 to 14.0 years. The overall survival rates at 1, 3, and 5 years after surgery were 90.9% (95%CI: 85.8%-96.0%), 68.4% (95%CI: 59.6%-77.2%), and 60.1% (95%CI: 50.5%-69.7%), respectively. The recurrence-free survival rates of patients with and without lymph node metastasis before surgery were 57.6% and 56.7%, respectively (OR=1.062, 95% CI: 0.525-2.148, P=0.864), and the overall survival rates were 61.5% and 57.7%, respectively (OR=1.019, 95% CI: 0.512-2.033, P=0.957), with no significant differences both. The recurrence-free survival rates of patients with melanoma (47 cases) and non-melanoma (83 cases) were 40.4% and 67.5%, respectively (OR=2.576, 95% CI: 1.390-4.775, P<0.001), and the overall survival rates were 42.6% and 67.5%, respectively (OR=2.845, 95% CI: 1.549-5.225, P<0.001), with significant differences both. Conclusions: The primary indications for OE are malignant tumors of the conjunctiva and eyelids, with melanoma being the most common malignant tumor of the conjunctiva. Melanoma patients who undergo OE have a lower survival rate compared to other types of malignant tumors. Nevertheless, even in the presence of tumor lymph node metastasis, patients can achieve a relatively good prognosis through OE.

EGFR targeted thermosensitive liposomes: A novel multifunctional platform for simultaneous tumor targeted and stimulus responsive drug delivery

Simple SummaryOphthalmic malignancies refer to rare, highly diversified, aggressive neoplasms. Unlike other types of solid tumors, tissue biopsy is not recommended for intraocular malignancies so a limited number of tissue samples are available for translational research programs. To date, very few biobanks dedicated to ophthalmic malignancies have been reported. The aim of this article was to present the challenges raised by ophthalmic malignancies in order to obtain biospecimens for research purposes, and the biobank dedicated to ophthalmic malignancies set up in our institution (Côte d’Azur University, Nice, France) was detailed. There is an urgent need to develop ocular malignancy biobanks to enhance translational research projects, develop international collaborations, and, ultimately, optimize customized medicine for the treatment of these tumors.Ophthalmic malignancies include various rare neoplasms involving the conjunctiva, the uvea, or the periocular area. These tumors are characterized by their scarcity as well as their histological, and sometimes genetic, diversity. Uveal melanoma (UM) is the most common primary intraocular malignancy. UM raises three main challenges highlighting the specificity of ophthalmic malignancies. First, UM is a very rare malignancy with an estimated incidence of 6 cases per million inhabitants. Second, tissue biopsy is not routinely recommended due to the risk of extraocular dissemination. Third, UM is an aggressive cancer because it is estimated that about 50% of patients will experience metastatic spread without any curative treatment available at this stage. These challenges better explain the two main objectives in the creation of a dedicated UM biobank. First, collecting UM samples is essential due to tissue scarcity. Second, large-scale translational research programs based on stored human samples will help to better determine UM pathogenesis with the aim of identifying new biomarkers, allowing for early diagnosis and new targeted treatment modalities. Other periocular malignancies, such as conjunctival melanomas or orbital malignancies, also raise specific concerns. In this context, the number of biobanks worldwide dedicated to ocular malignancies is very limited. The aims of this article were (i) to describe the specific challenges raised by a dedicated ocular malignancy biobank, (ii) to report our experience in setting up such a biobank, and (iii) to discuss future perspectives in this field.

In solid tumors, rapid local intravascular release of anticancer agents, e.g., doxorubicin (DOX), from thermosensitive liposomes (TSLs) can be an option to overcome poor extravasation of drug nanocarriers. The driving force of DOX penetration is the drug concentration gradient between the vascular compartment and the tumor interstitium. In this feasibility study, we used fibered confocal fluorescence microscopy (FCFM) to monitor in real-time DOX penetration in the interstitium of a subcutaneous tumor after its intravascular release from TSLs, Thermodox®. Cell uptake kinetics of the released DOX was quantified, along with an in-depth assessment of released-DOX penetration using an evolution model. A subcutaneous rat R1 rhabdomyosarcoma xenograft was used. The rodent was positioned in a setup including a water bath, and FCFM identification of functional vessels in the tumor tissue was applied based on AngioSense. The tumor-bearing leg was immersed in the 43°C water for preheating, and TSLs were injected intravenously. Real-time monitoring of intratumoral (i.t.) DOX penetration could be performed, and it showed the progressing DOX wave front via its native fluorescence, labeling successively all cell nuclei. Cell uptake rates (1/k) of 3 minutes were found (n=241 cells), and a released-DOX penetration in the range of 2500 µm2·s−1 was found in the tumor extravascular space. This study also showed that not all vessels, identified as functional based on AngioSense, gave rise to local DOX penetration.

Induction of local tissue hyperthermia is emerging as a valuable tool in cancer therapy, as temperatures between 39-43°C are sufficient to trigger release of drug from thermosensitive liposomes (TSL), but is not harmful to normal tissue. Despite significant advances in spatial and dynamic control of ultrasound, temperature profiles in heated tissues are never homogenous, and an ideal TSL should achieve complete local release over the entire hyperthermia range. We have developed a TSL exhibiting a sensitive temperature release profile (39-43°C) with excellent stability at 37°C. We prepared a TSL composed of DPPC lipid and Brij78 surfactant, and loaded this hyperthermia-activated-cytotoxic (HaT) TSL with doxorubicin (DOX). EMT-6 breast tumors located on a Balb/c mouse footpad were instantaneously heated to 42-43°C using a 3.9 MHz planar transducer: body temperature did not elevate above 37°C, and complete remission of the EMT-6 breast cancer tumors was observed. Mice treated with standard DOX chemotherapy (at same 10 mg/kg dose as HaT) did not exhibit any tumor inhibition effects compared to control mice. By histological examination, no physiological damage to normal tissues was induced by ultrasound heating, and mice treated with HaT DOX regained normal tissue appearance and function posttreatment. This study confirms the benefit of coupling ultrasound induced hyperthermia with a sensitive TSL formulation.

Safety of Moxifloxacin as Shown in Animal and In Vitro Studies

Rationale: Magnetic resonance imaging (MRI) is one of the most widely used diagnostic tools in the clinic. In this setting, real-time monitoring of therapy and tumor site would give the clinicians a handle to observe therapeutic response and to quantify drug amount to optimize the treatment. In this work, we developed a liposome-based cargo (cancer drugs) delivery strategy that could simultaneously monitor the real-time alternating magnetic field-induced cargo release from the change in MRI relaxation parameter R1 and the location and condition of liposome from the change in R2. The tumor site can then be monitored during the cargo release because liposomes would passively target the tumor site through the enhanced permeability and retention (EPR) effect. Physical insights from the experimental results and corresponding Monte Carlo spin dynamics simulations were also discussed.Methods: Superparamagnetic iron oxide (SPIO) nanoparticles, diethylenetriaminepentaacetic acid gadolinium(III) (Gd(III)-DTPA), and a model cancer drug (fluorescein) were co-loaded in PEGylated thermosensitive liposomes. The liposomes were characterized by transmission electron cryo-microscopy (cryoTEM), dynamic light scattering (DLS), and inductively coupled plasma optical emission spectrometry (ICP-OES). Alternating magnetic field (AMF) was used to create controlled mild hyperthermia (39-42°C) and facilitate controlled cargo (fluorescein) release from the thermosensitive liposomes. MRI relaxation parameters, R1 and R2, were measured at room temperature. The temporal variation in R1 was used to obtain the temporal profile of cargo release. Due to their similar sizes, both the gadolinium and cargo (model cancer drug fluorescein) would come out of the liposomes together as a result of heating. The temporal variation in R2 was used to monitor SPIO nanoparticles to enhance the tumor contrast. Monte Carlo spin dynamics simulations were performed by solving the Bloch equations and modeling SPIO nanoparticles as magnetized impenetrable spheres.Results: TEM images and DLS measurements showed the diameter of the liposome nanoparticle ~ 200 nm. AMF heating showed effective release of the model drug. It was found that R1 increased linearly by about 70% and then saturated as the cargo release process was completed, while R2 remained approximately constant with an initial 7%-drop and then recovered. The linear increase in R1 is consistent with the expected linear cargo release with time upon AMF heating. Monte Carlo spin dynamics simulations suggest that the initial temporal fluctuation of R2 is due to the plausible changes of SPIO aggregation and the slow non-recoverable degradation of liposomal membrane that increases water permeability with time by the heating process. The simulations show an order of magnitude increase in R2 at higher water permeability.Conclusion: We have performed MR parameter study of the release of a cargo (model cancer drug, fluorescein) by magnetic heating from thermosensitive multifunctional liposomes loaded with dual contrast agents. The size of the liposome nanoparticles loaded with model cancer drug (fluorescein), gadolinium chelate, and SPIO nanoparticles was appropriate for a variety of cancer therapies. A careful and detailed analysis with theoretical explanation and simulation was carried out to investigate the correlation between MRI relaxation parameters, R1 and R2, and different cargo release fractions. We have quantified the cargo release using R1, which shows a linear relation between each other. This result provides a strong basis for the dosage control of drug delivered. On the other hand, the fairly stable R2 with almost constant value suggests that it could be used to monitor the position and condition of the liposomal site, as SPIO nanoparticles mostly remained in the aqueous core of the liposome. Because our synthesized SPIO-encapsulated liposomes could be targeted to tumor site passively by the EPR effect, or actively through magnetofection, this study provides a solid ground for developing MR cancer theranostics in combination of this nanostructure and AMF heating strategy. Furthermore, our simulation results predict a sharp increase in R2 during the AMF heating, which opens up the exciting possibility of high-resolution, high-contrast real-time imaging of the liposomal site during the drug release process, provided AMF heating could be incorporated into an MRI setup. Our use of the clinically approved materials, along with confirmation by theoretical simulations, make this technique a promising candidate for translational MR cancer theranostics.

Surrogate MRI markers for hyperthermia-induced release of doxorubicin from thermosensitive liposomes in tumors

In vitro activity of caspofungin and voriconazole against uncommon Candida spp.

Hyperthermia-induced doxorubicin delivery from thermosensitive liposomes via MR-HIFU in a pig model