Combination of hyperthermia and bortezomib results in additive killing in mantle cell lymphoma cells

Hyperthermia Treatment as a Promising Anti-Cancer Strategy: Therapeutic Targets, Perspective Mechanisms and Synergistic Combinations in Experimental Approaches

Despite recent developments in diagnosis and treatment options, cancer remains one of the most critical threats to health. Several anti-cancer therapies have been identified, but further research is needed to provide more treatment options that are safe and effective for cancer. Hyperthermia (HT) is a promising treatment strategy for cancer because of its safety and cost-effectiveness. This review summarizes studies on the anti-cancer effects of HT and the detailed mechanisms. In addition, combination therapies with anti-cancer drugs or natural products that can effectively overcome the limitations of HT are reviewed because HT may trigger protective events, such as an increase of heat shock proteins (HSPs). In the 115 reports included, the mechanisms related to apoptosis, cell cycle, reactive oxygen species, mitochondrial membrane potential, DNA damage, transcription factors and HSPs were considered important. This review shows that HT is an effective inducer of apoptosis. Moreover, the limitations of HT may be overcome using combined therapy with anti-cancer drugs or natural products. Therefore, appropriate combinations of such agents with HT will exert maximal effects to treat cancer.

Ethanol Enhances Hyperthermia-Induced Cell Death in Human Leukemia Cells

Ethanol has been shown to exhibit therapeutic properties as an ablative agent alone and in combination with thermal ablation. Ethanol may also increase sensitivity of cancer cells to certain physical and chemical antitumoral agents. The aim of our study was to assess the potential influence of nontoxic concentrations of ethanol on hyperthermia therapy, an antitumoral modality that is continuously growing and that can be combined with classical chemotherapy and radiotherapy to improve their efficiency. Human leukemia cells were included as a model in the study. The results indicated that ethanol augments the cytotoxicity of hyperthermia against U937 and HL60 cells. The therapeutic benefit of the hyperthermia/ethanol combination was associated with an increase in the percentage of apoptotic cells and activation of caspases-3, -8 and -9. Apoptosis triggered either by hyperthermia or hyperthermia/ethanol was almost completely abolished by a caspase-8 specific inhibitor, indicating that this caspase plays a main role in both conditions. The role of caspase-9 in hyperthermia treated cells acquired significance whether ethanol was present during hyperthermia since the alcohol enhanced Bid cleavage, translocation of Bax from cytosol to mitochondria, release of mitochondrial apoptogenic factors, and decreased of the levels of the anti-apoptotic factor myeloid cell leukemia-1 (Mcl-1). The enhancement effect of ethanol on hyperthermia-activated cell death was associated with a reduction in the expression of HSP70, a protein known to interfere in the activation of apoptosis at different stages. Collectively, our findings suggest that ethanol could be useful as an adjuvant in hyperthermia therapy for cancer.

Effective production of multifunctional magnetic-sensitive biomaterial by an extrusion-based additive manufacturing technique

A calcium phosphate (CaP)-based scaffold used as synthetic bone grafts, which smartly combines precise dimensions, controlled porosity and therapeutic functions, presents benefits beyond those offered by conventional practices, although its fabrication is still a challenge. The sintering step normally required to improve the strength of the ceramic scaffolds precludes the addition of any biomolecules or functional particles before this stage. This study presents a proof of concept of multifunctional CaP-based scaffolds, fabricated by additive manufacturing from an innovative ink composition, with potential for bone regeneration, cancer treatment by local magnetic hyperthermia and drug delivery platforms. Highly loaded inks comprising iron-doped hydroxyapatite and β-tricalcium phosphate powders suspended in a chitosan-based solution, in the presence of levofloxacin (LEV) as model drug and magnetic nanoparticles (MNP), were developed. The sintering step was removed from the production process, and the integrity of the printed scaffolds was assured by the polymerization capacity of the ink composite, using genipin as a crosslinking agent. The effects of MNP and LEV on the inks' rheological properties, as well as on the mechanical and structural behaviour of non-doped and iron-doped scaffolds, were evaluated. Magnetic and magneto-thermal response, drug delivery and biological performance, such as cell proliferation in the absence and presence of an applied magnetic field, were also assessed. The addition of a constant amount of MNP in the iron-doped and non-doped CaP-based inks enhances their magnetic response and induction heating, with these effects more pronounced for the iron-doped CaP-based ink. These results suggest a synergistic effect between the iron-doped CaP-based powders and the MNP due to ferro/ferrimagnetic interactions. Furthermore, the iron presence enhances human mesenchymal stem cell metabolic activity and proliferation.

Clinical and Prognostic Significance of Cell Sensitivity to Chemotherapy Detected in vitro on Treatment Response and Survival of Leukemia Patients

Multidrug resistance (MDR) is a major challenge in leukemia treatment. The objective of this study was to identity predictors of MDR to allow for rapid and economical assessment of the efficacy of planned antitumor therapy for leukemia patients. The study included 113 patients with acute and chronic leukemias. Prior to antitumor therapy, we measured the sensitivity of tumor cells of patients to the panel of chemotherapeutic drugs, together with MDR1 mRNA and P-glycoprotein (P-gp) expression as one of the mechanisms of MDR, and compared these data with the response to therapy. The scales for leukemia patients according to therapy response, drug sensitivity of tumor cells, MDR1 mRNA and P-gp levels, and the presence of unfavorable immunological and cytogenetic markers were introduced for subsequent correlation analysis. We show that the drug resistance of tumor cells of leukemia patients estimated in vitro at diagnosis correlates with a poor response to chemotherapy and is usually combined with aberrant and immature immunological markers, cytogenetic abnormalities, and a high expression of MDR1 mRNA and P-gp. All together, these factors indicate unfavorable prognosis and low survival of leukemia patients. Thus, the sensitivity of tumor cells to chemotherapeutic drugs measured in vitro at diagnosis may have prognostic value for individual types of leukemia.

Whole-body hyperthermia in combination with systemic therapy in advanced solid malignancies

Whole-body hyperthermia (WBH) might be beneficial for patients with metastasized solid malignancies when combined with systemic therapy. This review identified and summarized the phase I/II studies (n = 13/14) conducted using this combination of therapies. Most of the phase II studies used radiant heating methods in a thermal dose of 41.8 °C (1 h). All studies used classic chemotherapy. Great inter-study heterogeneity was observed regarding treatment regimes, included patients and reported response rates (12-89%). Ovarian cancer, colorectal adenocarcinoma, lung cancer and sarcoma have been studied most. Most reported toxicity (grade 3/4) was myelosuppression. Treatment related mortality was present (4 patients) in three out 14 phase II studies (350 evaluable patients, over 966 cycles of WBH with chemotherapy). Absence of phase III trials makes the additive value of WBH highly speculative. As modern oncology offers many less invasive treatments options, it is unlikely WBH will ever find its way in routine clinical care.

Short duration cancer treatment: inspired by a fast bio-resorbable smart nano-fiber device containing NIR lethal polydopamine nanospheres for effective chemo-photothermal cancer therapy

BACKGROUND

The objective of this study was to evaluate the efficacy of a combination of Photothermal therapy (PTT) and chemotherapy in a single nano-fiber platform containing lethal polydopamine nanopheres (PD NPs) for annihilation of CT 26 cancer cells.

METHOD

Polydioxanone (PDO) nanofiber containing PD and bortezomib (BTZ) was fabricated via electrospinning method. The content of BTZ and PD after optimization was 7% and 2.5% respectively with respect to PDO weight. PD NPs have absorption band in near-infrared (NIR) with resultant rapid heating capable of inducing cancer cell death. The samples was divided into three groups - PDO, PDO+PD, and PDO+PD-BTZ for analysis.

RESULTS

In combined treatment, PDO nanofiber alone could not inhibit cancer cell growth as it neither contain PD or BTZ. However, PDO+PD fiber showed a cell viability of approximately 20% after 72 hr of treatment indicating minimal killing via hyperthermia. In the case of PDO composite fiber containing BTZ, the effect of NIR irradiation reduced the viability of cancer cells down to around 5% after 72 h showing the efficiency of combination therapy on cancer cells elimination. However, due to higher photothermal conversion that may negatively affect normal cells above 46°C, we have employed 1 s "OFF" and 2 s "ON" after initial 9 s continuous irradiation to maintain the temperature between 42 and 46°C over 3 mins of treatment using 2 W/cm2; 808 nm laser which resulted to similar cell death.

CONCLUSION

In this study, combination of PTT and chemotherapy treatment on CT 26 colon cancer cells within 3 min resulted in effective cell death in contrast to single treatment of either PTT and chemotherapy alone. Our results suggest that this nanofiber device with efficient heating and remote control drug delivery system can be useful and convenient in the future clinical application for localized cancer therapy.

Titania-Coated Gold Nano-Bipyramids for Blocking Autophagy Flux and Sensitizing Cancer Cells to Proteasome Inhibitor-Induced Death

Targeting protein degradation is recognized as a valid approach to cancer therapy. The ubiquitin-proteasome system (UPS) and the autophagy-lysosome pathway are two major pathways for intracellular protein degradation. Proteasome inhibitors such as bortezomib are clinically approved for treating malignancies, but to date, they are still unsatisfactory for cancer therapy. This study identifies titania-coated gold nano-bipyramid (NBP/TiO2) nanostructures as an autophagic flux inhibitor, as the smallest NBP/TiO2 nanostructures induce significant autophagosome accumulation in human glioblastoma U-87 MG cells via blocking the autophagosome-lysosome fusion process and inhibiting lysosomal degradation. Further study indicates that NBP/TiO2 nanostructures reduce the intracellular level of mature cathepsin B and directly inhibit the proteolytic activity of cathepsin B, thereby further inhibiting trypsin-like proteolytic activity, which is a potential cotarget for UPS inhibition. NBP/TiO2 nanostructures interact synergistically with bortezomib to suppress the viability of U-87 MG cells, as the combined treatment synergistically induces the intracellular accumulation of ubiquitinated protein and endoplasmic reticulum stress. In addition, photothermal therapy further synergistically reduces the cell viability. In summary, this study suggests that NBP/TiO2 nanostructures function as a promising anticancer agent in combination with proteasome inhibitors.

PEGylated Cu3BiS3 hollow nanospheres as a new photothermal agent for 980 nm-laser-driven photothermochemotherapy and a contrast agent for X-ray computed tomography imaging

Developing multifunctional near-infrared (NIR) light-driven photothermal agents is in high demand for efficient cancer therapy. Herein, PEGylated Cu3BiS3 hollow nanospheres (HNSs) with an average diameter of 80 nm were synthesized through a facile ethylene glycol-mediated solvothermal route. The obtained PEGylated Cu3BiS3 HNSs exhibited strong NIR optical absorption with a large molar extinction coefficient of 4.1 × 10(9) cm(-1) M(-1) at 980 nm. Under the irradiation of a 980 nm laser with a safe power density of 0.72 W cm(-2), Cu3BiS3 HNSs produced significant photothermal heating with a photothermal transduction efficiency of 27.5%. The Cu3BiS3 HNSs also showed a good antitumoral drug doxorubicin (DOX) loading capacity and pH- and NIR-responsive DOX release behaviors. At a low dosage of 10 μg mL(-1), HeLa cells could be efficiently killed through a synergistic effect of chemo- and photothermo-therapy respectively based on the DOX release and the photothermal effect of Cu3BiS3 HNSs. In addition, Cu3BiS3 HNSs displayed a good X-ray computed tomography (CT) imaging capability. Furthermore, Cu3BiS3 HNSs could be used for efficient in vivo photothermochemotherapy and X-ray CT imaging of mice bearing melanoma skin cancer. This multifunctional theranostic nanomaterial shows potential promise for cancer therapy.

A multifunctional nanoparticulate theranostic system with simultaneous chemotherapeutic, photothermal therapeutic, and MRI contrast capabilities

Herein, a single-step, scalable approach for preparing a multifunctional, theranostic drug delivery system made out of paclitaxel, iron oxide nanoparticles, gold nanoparticles, and poly(ethylene oxide)-b-poly(ε-caprolactone) is reported.

Electrospun PLA/MWCNTs composite nanofibers for combined chemo- and photothermal therapy

Carbon nanotubes are effective thermal generators by absorbing near-infrared radiation (NIR). In this study, multiwalled carbon nanotubes (MWCNTs) and doxorubicin (DOX) were successfully electrospun into the poly-l-lactic acid (PLLA) nanofibers. It is confirmed that NIR radiation could not only initiate burst release of DOX from the fibers due to the relatively low glass transition temperature (Tg) of PLLA, but also significantly increase the temperature of fibers-covering tumor site. The multifunctional fibers showed increased cytotoxicity both in vitro and in vivo by the combination of photothermal induced hyperthermia and chemotherapy with DOX. This drug delivery system could be very useful and convenient in future clinical applications for localized cancer therapy.

STATEMENT OF SIGNIFICANCE

Combination of chemo- and photothermal therapy has been widely researched owing to its enhanced cancer treatment efficacy. In this study, chemotherapy and photothermal therapy were integrated into one single system using electrospun DOX/MWCNTs loaded PLLA nanofiber mats and the anti-cancer efficacy of the fibers was studied in vivo for the first time. The effective NIR irradiation control showed a typical switch on/off effect on the release behavior of drug. As local delivery system, the fibers maximize the drug concentration in tumor and keep the MWCNTs in the surroundings of tumor, thus allowing a repeated localized heating. The high porosity of nanofibers is easy for cell binding, which may present an attractive alternative for local hyperthermia treatment of easily metastasizing tumors.

Magnetic fluid hyperthermia enhances cytotoxicity of bortezomib in sensitive and resistant cancer cell lines

The proteasome inhibitor bortezomib (BZ) has shown promising results in some types of cancer, but in others it has had minimal activity. Recent studies have reported enhanced efficacy of BZ when combined with hyperthermia. However, the use of magnetic nanoparticles to induce hyperthermia in combination with BZ has not been reported. This novel hyperthermia modality has shown better potentiation of chemotherapeutics over other types of hyperthermia. We hypothesized that inducing hyperthermia via magnetic nanoparticles (MFH) would enhance the cytotoxicity of BZ in BZ-sensitive and BZ-resistant cancer cells more effectively than hyperthermia using a hot water bath (HWH). Studies were conducted using BZ in combination with MFH in two BZ-sensitive cell lines (MDA-MB-468, Caco-2), and one BZ-resistant cell line (A2780) at two different conditions, ie, 43°C for 30 minutes and 45°C for 30 minutes. These experiments were compared with combined application of HWH and BZ. The results indicate enhanced potentiation between hyperthermic treatment and BZ. MFH combined with BZ induced cytotoxicity in sensitive and resistant cell lines to a greater extent than HWH under the same treatment conditions. The observation that MFH sensitizes BZ-resistant cell lines makes this approach a potentially effective anticancer therapy platform.

Au capped magnetic core/mesoporous silica shell nanoparticles for combined photothermo-/chemo-therapy and multimodal imaging

Uniform Au NRs-capped magnetic core/mesoporous silica shell nanoellipsoids (Au NRs-MMSNEs) were prepared by coating a uniform layer of Au NRs on the outer surface of a magnetic core/mesoporous silica shell nanostructure, based on a two-step chemical self-assembly process. This multifunctional nanocomposite integrate simultaneous chemotherapy, photo-thermotherapy, in vivo MR-, infrared thermal and optical imaging into one single system. The obtained multifunctional nanoellipsoids showed very low cytotoxicity, and the cancer cell uptake and intracellular location of the nanoellipsoids were observed by confocal laser scanning microscopy and bio-TEM. Importantly, the prepared multifunctional nanoellipsoids showed high doxorubicin loading capacity and pH value-responsive release mainly due to the electrostatic interaction between DOX molecules and mesoporous silica surface. Besides, a synergistic effect of combined chemo- and photo-thermo therapy was found at moderate power intensity of NIR irradiation based on the DOX release and the photothermal effect of Au NRs.

KNK437, a benzylidene lactam compound, sensitises prostate cancer cells to the apoptotic effect of hyperthermia

Hyperthermia is known to serve as a powerful tool in the treatment of prostate cancer which is commonly diagnosed in men. Quercetin and KNK437, Hsp70 inhibitors, play an important role in blocking thermotolerance in some cancer cells. In the present study we investigated the effects of KNK437 and quercetin on the acquisition of thermotolerance and heat-induced apoptosis. Also, it was examined whether the possible mechanism triggering apoptotic pathway included caspase-3 activation in prostate cancer cells. For this purpose, PC-3 and LNCaP cells were treated with hyperthermia following pretreatment with or without KNK437 or quercetin. Thermotolerance was investigated by colony formation assay in these cells, while Hsp70 mRNA levels were measured by real time RT-PCR. Sandwich ELISA was used for detection of Hsp70 protein levels. Apoptosis was detected by flow cytometric annexin V binding assay and by western blot analysis of procaspase-3 and cleaved poly (ADP-ribose) polymerase levels. In our study, KNK437 and quercetin inhibited thermotolerance in a dose-dependent manner in PC-3 cells. KNK437 and quercetin decreased heat-induced accumulation of Hsp70 mRNA and protein in PC-3 and LNCaP cells. KNK437 and quercetin pretreatment enhanced the apoptotic effect of hyperthermia in both cells. We found that KNK437 was more effective than quercetin in inducing apoptotic cell death, activation of caspase-3, and cleavage of PARP in prostate cancer cells. We suggest that KNK437 is a useful agent for enhancing the efficiency of hyperthermic therapy which has less toxic side-effects in prostate cancer.

Current devices for high-performance whole-body hyperthermia therapy

For late-stage cancer, whole-body hyperthermia (WBH) is highly regarded by physicians as a promising alternative to conventional therapies. Although WBH is still under scrutiny due to potential toxicity, its benefits are incomparable, as diversified devices and very promising treatment protocols in this area are advanced into Phase II and III clinical trials. Following the introduction of the WBH principle, this paper comprehensively reviews the state-of-art high-performance WBH devices based on the heat induction mechanisms - radiation, convection and conduction. Through analyzing each category's physical principle and heat-induction property, the advantages and disadvantages of the devices are evaluated. Technical strategies and critical scientific issues are summarized. For future developments, research directions worth pursuing are presented in this article.

Heat Shock Protein translocation induced by membrane fluidization increases tumor-cell sensitivity to chemotherapeutic drugs

Treatment of chronic lymphocytic leukemia (CLL) remains a challenge due to the frequency of drug resistance amongst patients. Improving the delivery of chemotherapeutic agents while reducing the expression of anti-apoptotic Heat Shock Proteins (HSPs) within the cancer cells may facilitate in overcoming this drug resistance. We demonstrate for the first time that sub-lethal doses of chemotherapeutic agents can be combined with membrane fluidizing treatments to produce a significant increase in drug efficacy and apoptosis in vitro. We show that fluidizers result in a transient decrease in intracellular HSPs, resulting in increased tumor-cell sensitivity and a membrane-associated induction of HSP gene expression.