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Dox cytotoxicity assay and IC50 values for B16 (A, B) and BFS-1 cells (C, D) 48h after treatment by different hyperthermia protocols. n = 3 for each data set. Curves were fit by non-linear regression and statistical analysis by one-way ANOVA Bonferroni test. The significance scores of all treatments versus NT groups are indicated with asterisks. * = p < 0.05, ** = p < 0.01, *** = p < 0.005.
Source publication
Doxorubicin (Dox) loaded thermosensitive liposomes (TSLs) have shown promising results for
hyperthermia-induced local drug delivery to solid tumors. Typically, the tumor is heated to
hyperthermic temperatures (41-42 °C), which induced intravascular drug release from TSLs within the
tumor tissue leading to high local drug concentrations (1-step deli...
Similar publications
Mild hyperthermia (HT) (40-43 °C) has been combined with temperature-sensitive liposomes (TSL), offering on-demand drug release for increased drug bioavailability and reduced systemic toxicity. Different HT regimens have been applied to trigger liposome drug release in the blood vessels (intravascular) of heated tumours or following tumour extravas...
Citations
... The average thickness of the D nanostructure was ~ 13 nm, as disclosed in the cross-sectional plot (Fig. 2f ), with an increase in the sample thickness induced by the M13 phage, PEG polymer coating, and DOX. Recent studies have reported that the M13 exhibits a thickness of ~ 6 nm, whereas a thickness of a few nm is demonstrated for the case of the PEG and DOX [32,47,48]. Moreover, simulations revealed that pristine D nanostructure-in-DMEM models exhibited higher thermal stability or performance compared to that of the WS 2 -in-DMEM model with degradation (Supporting Fig. S2). ...
Clinical trials have generated encouraging outcomes for the utility of thermal agents (TAs) in cancer thermal therapy (TT). Although the fast breakdown of TAs alleviates safety concerns, it restricts the thermal stability necessary for effective treatment. TAs with excellent thermal stability, on the other hand, deteriorate slowly. Rare are the approaches that address the trade-off between high thermal stability and quick deterioration of TAs. Here we control the thermal signature of WS2-type 2D materials by utilizing previously undescribed DOX–WS2–PEG–M13 nanostructures (we term them D nanostructures) through Joule heating phenomena, and develop an integrated system for TT for enhancing thermal performance, and simultaneously, maintaining rapid degradation, and chemotherapy for efficacious treatment. A relative cell viability of ~ 50% was achieved by the D-based TT (DTT) configuration, as well as a 1 nM drug concentration. The D-driven chemotherapy (DCT) model also attains a relative cell viability of 80% for 1 nM drug concentration, while a 1-week degradation time was revealed by the D nanostructure. Theoretical studies elucidate the drug molecule–nanostructure and drug-on-nanostructure–solution interaction-facilitated enhancement in drug loading and drug release performance in DCT varieties. As a result, this work not only proposes a “ideal TA” that circumvents TA restrictions, but also enables proof-of-concept application of WS2-based materials in chemotherapy-unified combination cancer therapy.
Graphical Abstract
... Previous studies have shown that various DOX nanoformulations caused a more pronounced antitumor effect in vitro and in vivo when combined with hyperthermia [37][38][39]. Comparisons between free DOX and LDOX given in combination with different hyperthermia methods (water bath and infrared heating) revealed a significantly greater inhibition of tumor growth and reduced toxicity profiles in experimental sarcoma models [27,[40][41][42][43]. Another aspect of LDOX delivery in response to hyperthermia is that uniform distribution of the drug in a tumor can be expected within 40 h after treatment [44]. ...
... There is a growing body of evidence supporting considerable improvements in LDOX delivery and antitumor effects in response to hyperthermia [27,[40][41][42][43]. However, to our knowledge, the significance of this work is that we examined the effect of a combination treatment with LDOX and IMH induced by a radiofrequency electromagnetic field, the magnetic component of which propagated through the biological media with lower distortion relative to its electric component, in Saos-2 cells for the first time. ...
Despite efforts in osteosarcoma (OS) research, the role of inductive moderate hyperthermia (IMH) in delivering and enhancing the antitumor effect of liposomal doxorubicin formulations (LDOX) remains unresolved. This study investigated the effect of a combination treatment with LDOX and IMH on Saos-2 human OS cells. We compared cell viability using a trypan blue assay, apoptosis and reactive oxygen species (ROS) measured by flow cytometry and pro-apoptotic Bax protein expression examined by immunocytochemistry in response to IMH (42 MHz frequency, 15 W power for 30 min), LDOX (0.4 μg/mL), and LDOX plus IMH. The lower IC50 value of LDOX at 72 h indicated increased accumulation of the drug in the OS cells. LDOX plus IMH resulted in a 61% lower cell viability compared to no treatment. Moreover, IMH potentiated the LDOX action on the Saos-2 cells by promoting ROS production at temperatures of <42 °C. There was a 12% increase in cell populations undergoing early apoptosis with a less heterogeneous distribution of Bax after combination treatment compared to those treated with LDOX (p < 0.05). Therefore, we determined that IMH could enhance LDOX delivery and its antitumor effect via altered membrane permeabilization, ROS generation, and a lower level of visualized Bax heterogeneity in the Saos-2 cells, suggesting the potential translation of these findings into in vivo studies.
... Exposure to mild hyperthermia has been associated with cytotoxicity to tumor cells, improved chemosensitivity, and enhanced particle extravasation from the vasculature into the tumor microenvironment. 64 As expected, the optimal Asp/TLs (40°C) caused an impressive increase in the percentage of cell population among both the late apoptosis and necrosis quartiles (denoted by P-value #0.001) when compared to the free drug, Asp (40°C). Furthermore, exposure to the optimal Asp/TLs (40°C) resulted in a 72% reduction in the viable cells compared to the control, and about a two-fold decrease in viable cells to free Asp (40°C). ...
Herein, thermo-responsive liposomes (TLs) loaded with Asp (Asp/TLs) were produced by self-assembling DPPC, DSPE-PEG2000, and cholesterol. The preparation variables were optimized using the Box-Behnken design (BBD). The optimized Asp/TLs exhibited an average particle size of 114.05 ± 1.56 nm, PDI of 0.15 ± 0.015, zeta potential of −15.24 ± 0.65 mV, and entrapment efficiency (EE%) of 84.08 ± 2.75%. In addition, under physiological conditions, Asp/TLs showed spherical shape, outstanding stability and thermo-triggered the release of Asp at 38°C, reaching the maximum Asp release at 40°C. The MTT assay showed that the optimal Asp/TLs exhibited the highest cytotoxic activity upon exposure to mild hyperthermia (40°C) against the invasive triple-negative breast cancer cell line (MDA-MB-231) when compared to other preparations. The IC 50 of Asp/TLs (40°C) was estimated at 0.9 mg mL −1 , while that of free Asp (40°C) was 3.83 mg mL −1. As such, the optimal Asp/TLs were shown to increase the cytotoxic activity of Asp by 4-fold upon exposure to mild hyperthermia. The IC 50 values of Asp and Asp/TLs without exposure to 40°C were 6.6 mg mL −1 and 186 mg mL −1 , respectively. This indicated that Asp was released only when placed at 40°C. The apoptosis assay revealed that Asp/TLs (40°C) caused a remarkable increase in the percentage of cell population among both the late apoptosis and necrosis quartiles, as well as a significant decline in the viable cell quartile (P # 0.001) when compared to Asp (40°C). Asp/TLs (40°C) and Asp (40°C) could stimulate the intrinsic apoptosis pathway by upregulating the apoptotic genes Bak and Bax, while downregulating the anti-apoptotic genes, BCL-xL and BCL-2. The free Asp (40°C) increased the gene expression of Bak and Bax by 4.4-and 5.2-folds, while reducing the expression of BCL-xL and BCL-2 by 50% and 73%, respectively. The optimal Asp TLs (40°C) manifested more potent effects as demonstrated by the upregulation of Bak, Bax, and P53 by 5.6-, 7.2-, and 1.3-folds, as well as the downregulation of BCL-xL and BCL-2 by 70% and 85%, respectively. As such, the optimal Asp TLs (40°C) treatment displayed the most potent cytotoxic profile and induced both apoptosis and necrosis in MDA-MB-231.
... Different materials and nanostructures have been reported for this aim [199]. Among them, liposomes are one of the widely studied nanomaterials for photothermal responsive drug release [204][205][206]. For example, Zhu et al. reported a liposome composed of natural fatty acids, DOX and a NIR dye (IR780) for NIR-triggered drug release. ...
Remarkable progress in phototherapy has been made in recent decades, due to its non-invasiveness and instant therapeutic efficacy. In addition, with the rapid development of nanoscience and nanotechnology, phototherapy systems based on nanoparticles or nanocomposites also evolved as an emerging hotspot in nanomedicine research, especially in cancer. In this review, first we briefly introduce the history of phototherapy, and the mechanisms of phototherapy in cancer treatment. Then, we summarize the representative development over the past three to five years in nanoparticle-based phototherapy and highlight the design of the innovative nanoparticles thereof. Finally, we discuss the feasibility and the potential of the nanoparticle-based phototherapy systems in clinical anticancer therapeutic applications, aiming to predict future research directions in this field. Our review is a tutorial work, aiming at providing useful insights to researchers in the field of nanotechnology, nanoscience and cancer.
... For the treatment of solid tumors, conventional chemotherapy using low molecular weight and smallsized cytotoxic drugs (less than 1 nm in diameter) is commonly used [1]. A large number of anticancer drugs were produced with considerable cytotoxicity demonstrated in preclinical investigations; however, their clinical applicability is restricted for numerous reasons. ...
Poor half-life, short circulation, systemic toxicity, insufficient accumulation, and ultimately weak therapeutic response are the most important obstacles in the conventional chemotherapy. Thermosensitive liposomes (TSLs) with encapsulated anti-cancer drug doxorubicin combined with high intensity focused ultrasound (HIFU) has the potential to overcome the shortcomings of conventional chemotherapy through targeted drug delivery. In the HIFU-TSL drug delivery system, complex physicochemical and biological processes are involved; however, many works in this field suffer from a comprehensive analysis. Regarding this, the present study has the novelty of developing an advanced multi-physical and multi-compartment model to simulate the complex processes in conventional and TSL-mediated chemotherapy paired with HIFU-induced hyperthermia. Elaborating the determinant role of tumor microenvironment is another novelty, which was underrepresented in earlier investigations and is noticed in our study through the modeling of hypoxic region. Additionally, unlike previous studies that used the classical bio-heat transfer model, this study has innovation in considering the thermal inertia as well as microstructural interactions in the bio-heat transfer equation. Last by not the least, many researchers evaded the harms of continuous irradiation, which in the present work is replaced by pulsed ultrasound as an emerging method for thermal necrosis and mild hyperthermia. The results reveal that the hypoxic region prevents efficient drug delivery due to the disruption of microvascular network and reduces chemotherapy-induced cell death. A comparison between targeted drug delivery and conventional chemotherapy suggests that TSL-mediated drug delivery leads to increased cell death by more than 100% by providing high circulation time and improved bioavailability. Besides this, increasing the acoustic power (from 3 to 8.7 W) leads to a desirable achievement, which is thermal necrosis of central tumor region and high fraction of killed cells (FKCs). The FKCs in the proposed HIFU-TSL system reaches about 58% (3 W), 60% (4.1 W), 70% (7 W), and 78% (8.7 W) at 24 h after TSL-doxorubicin administration, while this value is about 30% in the conventional chemotherapy. In conclusion, this study confirms the benefits of HIFU-TSL drug delivery system. This method has the potential to be used as a targeted drug delivery system to improve anti-cancer drug efficacy, while considerably prevents the normal tissue damage.
... Apart from 99m Tc, the other commonly used γ-emitters is 111 In with a longer half-life (2.8 days), allowing the in vivo imaging 48 h postadministration. Several studies have focused on using DTPAconjugated liposomes to enable the chelation with 111 In [94][95][96][97][98][99]. The ability of 111 In-DTPA complex-labeled PEGylated liposomal doxorubicin (Doxil®) to deposit in the region of tumor based on the enhanced permeability and retention (EPR) effect was investigated in human ovarian cancer mouse xenograft models using SPECT/CT imaging, where the tumor tissues could be clearly visualized from an axial view [94]. ...
... Duan et al. also investigated the biodistribution of a pH-sensitive long-circulating liposome using the same method [96]. Additionally, a direct comparison of the 111 In-DTPA complex-based thermosensitive liposomes (TSLs) accumulation in vivo at physiological temperatures and after hyperthermia treatment using SPECT imaging was provided by Lokerse et al. [97]. Improved liposomal uptake and retention was observed in the case of preheated by hyperthermia followed by the injection of TSLs [97], suggesting the potential enhanced EPR effect induced by hyperthermia. ...
... Additionally, a direct comparison of the 111 In-DTPA complex-based thermosensitive liposomes (TSLs) accumulation in vivo at physiological temperatures and after hyperthermia treatment using SPECT imaging was provided by Lokerse et al. [97]. Improved liposomal uptake and retention was observed in the case of preheated by hyperthermia followed by the injection of TSLs [97], suggesting the potential enhanced EPR effect induced by hyperthermia. More interestingly, Lamichhane et al. reported a dual-molecular liposomal imaging system, that is, 111 In-loaded liposome encapsulating a novel 18 F-labeled carboplatin derivative [98], which allows the dual-radiolabeling of a single nanoparticle for both the carrier and the drug distribution using SPECT and PET imaging, respectively. ...
Metal complexes are of increasing interest as pharmaceutical agents in cancer diagnostics and therapeutics, while some of them suffer from issues such as limited water solubility and severe systemic toxicity. These drawbacks severely hampered their efficacy and clinical applications. Liposomes hold promise as delivery vehicles for constructing metal complex-based liposomes to maximize the therapeutic efficacy and minimize the side effects of metal complexes. This review provides an overview on the latest advances of metal complex-based liposomal delivery systems. First, the development of metal complex-mediated liposomal encapsulation is briefly introduced. Next, applications of metal complex-based liposomes in a variety of fields are overviewed, where drug delivery, cancer imaging (single photon emission computed tomography (SPECT), positron emission tomography (PET), and magnetic resonance imaging (MRI)), and cancer therapy (chemotherapy, phototherapy, and radiotherapy) were involved. Moreover, the potential toxicity, action of toxic mechanisms, immunological effects of metal complexes as well as the advantages of metal complex-liposomes in this content are also discussed. In the end, the future expectations and challenges of metal complex-based liposomes in clinical cancer therapy are tentatively proposed.
... However, the release of the drug at normothermia (37°C) was prolonged, and less cytotoxic potential was observed than the free drug. Similar findings demonstrating the effect of temperature on intracellular internalization and cytotoxicity were reported by Lokerse et al. 82 Hemolytic Potential ...
Background
Most of the traditional nanocarriers of cancer therapeutic moieties present dose-related toxicities due to the uptake of chemotherapeutic agents in normal body cells. The severe life-threatening effects of systemic chemotherapy are well documented. Doxorubicin, DOX is the most effective antineoplastic agent but with the least specific action that is responsible for severe cardiotoxicity and myelosuppression that necessitates careful monitoring while administering. Stimuli-sensitive/intelligent drug delivery systems, specifically those utilizing temperature as an external stimulus to activate the release of encapsulated drugs, have become a subject of recent research. Thus, it would be ideal to have a nanocarrier comprising safe excipients and controllable drug release capacity to deliver the drug at a particular site to minimize unwanted and toxic effects of chemotherapeutics. We have developed a simple temperature-responsive nanocarrier based on eutectic mixture of fatty acids. This study aimed to develop, physicochemically characterize and investigate the biological safety of eutectic mixture of fatty acids as a novel construct for temperature-responsive drug release potential.
Methods
We have developed phase change material, PCM, based on a series of eutectic mixtures of fatty acids due to their unique and attractive physicochemical characteristics such as safety, stability, cost-effectiveness, and ease of availability. The reversible solid-liquid phase transition of PCM is responsible to hold firm or actively release the encapsulated drug. The eutectic mixtures of fatty acids (stearic acid and myristic acid) along with liquid lipid (oleic acid) were prepared to exhibit a tunable thermoresponsive platform. Doxorubicin-loaded lipid nanocarriers were successfully developed with combined hot melt encapsulation (HME) and sonication method and characterized to achieve enhanced permeability and retention (EPR) effect-based solid tumor targeting in response to exogenous temperature stimulus. The cytotoxicity against melanoma cell lines and in vivo safety studies in albino rats was also carried out.
Results
Doxorubicin-loaded lipid nanocarriers have a narrow size distribution (94.59–219.3 nm), and a PDI (0.160–0.479) as demonstrated by photon correlation microscopy and excellent colloidal stability (Z.P value: −22.7 to −32.0) was developed. Transmission electron microscopy revealed their spherical morphology and characteristics of a monodispersed system. A biphasic drug release pattern with a triggered drug release at 41°C and 43°C and a sustained drug release was observed at 37°C. The thermoresponsive cytotoxic potential was demonstrated in B16F10 cancer cell lines. Hemolysis assay and acute toxicity studies with drug-free and doxorubicin lipid nanocarrier formulations provided evidence for their non-toxic nature.
Conclusion
We have successfully developed a temperature-responsive tunable platform with excellent biocompatibility and intelligent drug release potential. The formulation components being from natural sources present superior characteristics in terms of cost, compatibility with normal body cells, and adaptability to preparation methods. The reported preparation method is adapted to avoid complex chemical processes and the use of organic solvents. The lipid nanocarriers with tunable thermoresponsive characteristics are promising biocompatible drug delivery systems for improved localized delivery of chemotherapeutic agents.
... More than 85% of human cancers are solid tumors, a deadly and dangerous disease worldwide [1,2]. Conventional chemotherapy for the treatment of solid tumors is the basic treatment that uses cytotoxic drugs to counteract the proliferation of cancer cells [3]. However, the side effects of conventional chemotherapy are a major challenge for this treatment strategy. ...
Computational models have been developed as a potential platform to identify bio-interactions that cannot be properly understood by experimental models. In the present study, a mathematical model has been employed to investigate the therapeutic response of drug-loaded thermosensitive liposome (TSL) following intravascular release paradigm. Thermal field created by an alternating magnetic field is utilized to release the drug within microvessels. Determining the time required for the application of magneto-hyperthermia is the main purpose of this study. Results show that applying a long-term continuous or pulsed hyperthermia can affect the concentration level of drugs in the extracellular space. The peak value of free and bound drug concentrations in the extracellular space is equal for all hyperthermia programs. Additionally, the concentrations of free and bound drugs are retained at a higher level in pulsed mode compared to the continuous mode (i.e., area under curve (AUC) of pulsed case is slightly higher than continuous case). However, there is no significant difference in bioavailability time. Hence, onset time of tumor growth is similar for different conditions. This study shows that the appropriate time to apply hyperthermia is post-bolus injection until reaching the peak concentration profile in extracellular space. Therefore, in clinical applications similar to the present study’s circumstances, continuous hyperthermia for 30 min can be a better choice. This study can be a useful guideline for experimental studies to reduce the number of in vivo tests as well as for clinical trials to make the right decision to provide optimal medication programs.
... Several in vivo studies have reported the lower therapeutic efficacy of such approach compared to mice injected with fast-releasing TSL-Dox formulations combined with a single HT treatment. Despite the fact that these studies explored different TSL formulations and two-step HT approaches [11][12][13], the majority of these reports relied on assessing the therapeutic efficacy of this HT regimen by delaying tumour growth, but with limited quantification of Dox (released or encapsulated) in the tumour tissues. ...
... The latter approach is based on applying HT prior to TSL injection to benefit from HT's enhanced tumour accumulation caused by HT, followed by a second HT to trigger drug release from the extravasated TSL. Several studies have reported lower therapeutic efficacy of such an approach than mice injected with fast-releasing TSL-Dox formulations, where intravascular drug release occurs; however, limited investigations have been carried out to understand this finding [11][12][13]. Li et al. previously showed that level of Dox in tumours treated with two-step HT was comparable to tumours treated with fast-releasing TSL combined with HT (intravascular release), but no evidence of in vivo Dox release was provided, which could have explained the lower therapeutic efficacy of two-step HT. Lokerse et al. studied the tumour accumulation of radiolabeled TSL using SPECT/CT in murine melanoma B16F10 and murine sarcoma BFS-1 tumour models following a two-step HT application. ...
... Lokerse et al. studied the tumour accumulation of radiolabeled TSL using SPECT/CT in murine melanoma B16F10 and murine sarcoma BFS-1 tumour models following a two-step HT application. In that paper, the authors attributed the lower therapeutic efficacy of traditional TSL combined with two-step HT to a lower Dox level in tumours treated with fasting releasing TSL (intravascular release) due to Dox leakage from circulating TSL over time [13]. It is worth mentioning that both studies used TTSL formulations slightly different to our TTSL and applied different 2-step HT regimens. ...
Mild hyperthermia (HT) (40-43 °C) has been combined with temperature-sensitive liposomes (TSL), offering on-demand drug release for increased drug bioavailability and reduced systemic toxicity. Different HT regimens have been applied to trigger liposome drug release in the blood vessels (intravascular) of heated tumours or following tumour extravasation (interstitial). The present study systematically assessed the in vivo doxorubicin (Dox) release and therapeutic efficacy of Dox-loaded TSL with different release profiles. Low temperature-sensitive liposomes (LTSL-Dox), traditional-temperature-sensitive liposomes (TTSL-Dox), and non-temperature-sensitive liposomes (NTSL-Dox) were combined with a single or two HT in different tumour models (murine melanoma B16F10 tumour and human breast MDA-MB-435). The efficacy of each treatment was assessed by monitor tumour growth and mice survival. The level of Dox in tumour tissues was quantified using 14C-Dox and liquid scintillation while Dox release was assessed using live imaging and confocal laser scanning microscopy. Applying a second HT to release Dox from extravasated TTSL-Dox was not therapeutically superior to single HT application due to Dox clearance from the extravasated TTSL-Dox. Our findings revealed that enhanced blood perfusion in heated tumours during the second water bath HT could be seen as a hurdle for TTSL-Dox's anticancer efficacy, where the systemic toxicity of the redistributed Dox from the tumour tissues could be potentiated.
... The application of heat is able to induce both a cellular and physiological response, and it could therefore lead to multifactorial therapeutic benefits [1]. However, this is highly dependent on several factors such as the achieved temperature, exposure time, tumor location, thermotolerance of the targeted cells, and tumor vascular bed [2,3]. The window model consisted of two non-symmetrical frames that are made of polyether ether ketone (PEEK); (B) local hyperthermia was provided by an external circular resistive electric heating coil; (C) the window was secured to the heating element using screws in combination with the chamber-to-stage platform on the microscope; (D) the DSC model set-up consisted of (a) microscope objective, (b) chamber-to-stage holder, (c) external heating element, (d) dorsal skinfold chamber, and (e) heating platform for the maintenance of the core body temperature of the animal. ...
This paper presents three devices suitable for the preclinical application of hyperthermia via the simultaneous high-resolution imaging of intratumoral events. (Pre)clinical studies have confirmed that the tumor micro-environment is sensitive to the application of local mild hyperthermia. Therefore, heating is a promising adjuvant to aid the efficacy of radiotherapy or chemotherapy. More so, the application of mild hyperthermia is a useful stimulus for triggered drug release from heat-sensitive nanocarriers. The response of thermosensitive nanoparticles to hyperthermia and ensuing intratumoral kinetics are considerably complex in both space and time. To obtain better insight into intratumoral processes, longitudinal imaging (preferable in high spatial and temporal resolution) is highly informative. Our devices are based on (i) an external electric heating adaptor for the dorsal skinfold model, (ii) targeted radiofrequency application, and (iii) a microwave antenna for heating of internal tumors. These models, while of some technical complexity, significantly add to the understanding of effects of mild hyperthermia warranting implementation in research on hyperthermia.
