Role of Hyperthermia in Breast Cancer Locoregional Recurrence: A Review

Recent advancements of hydrogels in immunotherapy: Breast cancer treatment

Breast cancer is the most prevalent cancer among women and the leading cause of cancer-related deaths in this population. Recent advances in Immunotherapy, or combined immunotherapy, offering a more targeted and less toxic approach, expand the survival rate of patients more than conventional treatment. Notably, hydrogels, a versatile platform provided promising avenues to combat breast cancer in preclinical studies and extended to clinical practices. With advantages such as the alternation of tumor microenvironment, immunomodulation, targeted delivery of therapeutic agents, and their sustained release at specific sites of interest, hydrogels can potentially be used for the treatment of breast cancer. This review highlights the advantages, mechanisms of action, stimuli-responsiveness properties, and recent advancements of hydrogels for treating breast cancer immunotherapy. Moreover, post-treatment and its clinical translations are discussed in this review. The integration of hydrogels in immunotherapy strategies may pave the way for more effective, personalized, and patient-friendly approaches to combat breast cancer, ultimately contributing to a brighter future for breast cancer patients.

How Magnetic Composites are Effective Anticancer Therapeutics? A Comprehensive Review of the Literature

Chemotherapy is the most prominent route in cancer therapy for prolonging the lifespan of cancer patients. However, its non-target specificity and the resulting off-target cytotoxicities have been reported. Recent in vitro and in vivo studies using magnetic nanocomposites (MNCs) for magnetothermal chemotherapy may potentially improve the therapeutic outcome by increasing the target selectivity. In this review, magnetic hyperthermia therapy and magnetic targeting using drug-loaded MNCs are revisited, focusing on magnetism, the fabrication and structures of magnetic nanoparticles, surface modifications, biocompatible coating, shape, size, and other important physicochemical properties of MNCs, along with the parameters of the hyperthermia therapy and external magnetic field. Due to the limited drug-loading capacity and low biocompatibility, the use of magnetic nanoparticles (MNPs) as drug delivery system has lost traction. In contrast, MNCs show higher biocompatibility, multifunctional physicochemical properties, high drug encapsulation, and multi-stages of controlled release for localized synergistic chemo-thermotherapy. Further, combining various forms of magnetic cores and pH-sensitive coating agents can generate a more robust pH, magneto, and thermo-responsive drug delivery system. Thus, MNCs are ideal candidate as smart and remotely guided drug delivery system due to a) their magneto effects and guide-ability by the external magnetic fields, b) on-demand drug release performance, and c) thermo-chemosensitization under an applied alternating magnetic field where the tumor is selectively incinerated without harming surrounding non-tumor tissues. Given the important effects of synthesis methods, surface modifications, and coating of MNCs on their anticancer properties, we reviewed the most recent studies on magnetic hyperthermia, targeted drug delivery systems in cancer therapy, and magnetothermal chemotherapy to provide insights on the current development of MNC-based anticancer nanocarrier.

Feasibility of ultrasound tomography-guided localized mild hyperthermia using a ring transducer: Ex vivo and in silico studies

BACKGROUND

As of 2022, breast cancer continues to be the most diagnosed cancer worldwide. This problem persists within the United States as well, as the American Cancer Society has reported that ∼12.5% of women will be diagnosed with invasive breast cancer over the course of their lifetime. Therefore, a clinical need continues to exist to address this disease from a treatment and therapeutic perspective. Current treatments for breast cancer and cancers more broadly include surgery, radiation, and chemotherapy. Adjuncts to these methods have been developed to improve the clinical outcomes for patients. One such adjunctive treatment is mild hyperthermia therapy (MHTh), which has been shown to be successful in the treatment of cancers by increasing effectiveness and reduced dosage requirements for radiation and chemotherapies. MHTh-assisted treatments can be performed with invasive thermal devices, noninvasive microwave induction, heating and recirculation of extracted patient blood, or whole-body hyperthermia with hot blankets.

PURPOSE

One common method for inducing MHTh is by using microwave for heat induction and magnetic resonance imaging for temperature monitoring. However, this leads to a complex, expensive, and inaccessible therapy platform. Therefore, in this work we aim to show the feasibility of a novel all-acoustic MHTh system that uses focused ultrasound (US) to induce heating while also using US tomography (UST) to provide temperature estimates. Changes in sound speed (SS) have been shown to be strongly correlated with temperature changes and can therefore be used to indirectly monitor heating throughout the therapy. Additionally, these SS estimates allow for heterogeneous SS-corrected phase delays when heating complex and heterogeneous tissue structures.

METHODS

Feasibility to induce localized heat in tissue was investigated in silico with a simulated breast model, including an embedded tumor using continuous wave US. Here, both heterogenous acoustic and thermal properties were modeled in addition to blood perfusion. We further demonstrate, with ex vivo tissue phantoms, the feasibility of using ring-based UST to monitor temperature by tracking changes in SS. Two phantoms (lamb tissue and human abdominal fat) with latex tubes containing varied temperature flowing water were imaged. The measured SS of the water at each temperature were compared against values that are reported in literature.

RESULTS

Results from ex vivo tissue studies indicate successful tracking of temperature under various phantom configurations and ranges of water temperature. The results of in silico studies show that the proposed system can heat an acoustically and thermally heterogenous breast model to the clinically relevant temperature of 42°C while accounting for a reasonable time needed to image the current cross section (200 ms). Further, we have performed an initial in silico study demonstrating the feasibility of adjusting the transmit waveform frequency to modify the effective heating height at the focused region. Lastly, we have shown in a simpler 2D breast model that MHTh level temperatures can be maintained by adjusting the transmit pressure intensity of the US ring.

CONCLUSIONS

This work has demonstrated the feasibility of using a 256-element ring array transducer for temperature monitoring; however, future work will investigate minimizing the difference between measured SS and the values shown in literature. A hypothesis attributes this bias to potential volumetric average artifacts from the ray-based SS inversion algorithm that was used, and that moving to a waveform-based SS inversion algorithm will greatly improve the SS estimates. Additionally, we have shown that an all-acoustic MHTh system is feasible via in silico studies. These studies have indicated that the proposed system can heat a tumor within a heterogenous breast model to 42°C within a narrow time frame. This holds great promise for increasing the accessibility and reducing the complexity of a future all-acoustic MHTh system.

In Vitro Examinations of Cell Death Induction and the Immune Phenotype of Cancer Cells Following Radiative-Based Hyperthermia with 915 MHz in Combination with Radiotherapy

Multimodal tumor treatment settings consisting of radiotherapy and immunomodulating agents such as immune checkpoint inhibitors are more and more commonly applied in clinics. In this context, the immune phenotype of tumor cells has a major influence on the anti-tumor immune response as well as the composition of the tumor microenvironment. A promising approach to further boost anti-tumor immune responses is to add hyperthermia (HT), i.e., heating the tumor tissue between 39 °C to 45 °C for 60 min. One key technique is the use of radiative hyperthermia systems. However, knowledge is limited as to how the frequency of the used radiative systems affects the immune phenotype of the treated tumor cells. By using our self-designed in vitro hyperthermia system, we compared cell death induction and expression of immune checkpoint molecules (ICM) on the tumor cell surface of murine B16 melanoma and human MDA-MB-231 and MCF-7 breast cancer cells following HT treatment with clinically relevant microwaves at 915 MHz or 2.45 GHz alone, radiotherapy (RT; 2 × 5 Gy or 5 × 2 Gy) alone or in combination (RHT). At 44 °C, HT alone was the dominant cell death inductor with inactivation rates of around 70% for B16, 45% for MDA-MB-231 and 35% for MCF-7 at 915 MHz and 80%, 60% and 50% at 2.45 GHz, respectively. Additional RT resulted in 5–15% higher levels of dead cells. The expression of ICM on tumor cells showed time-, treatment-, cell line- and frequency-dependent effects and was highest for RHT. Computer simulations of an exemplary spherical cell revealed frequency-dependent local energy absorption. The frequency of hyperthermia systems is a newly identified parameter that could also affect the immune phenotype of tumor cells and consequently the immunogenicity of tumors.

Cell mechanical properties of human breast carcinoma cells depend on temperature

The knowledge of cell mechanics is required to understand cellular processes and functions, such as the movement of cells, and the development of tissue engineering in cancer therapy. Cell mechanical properties depend on a variety of factors, such as cellular environments, and may also rely on external factors, such as the ambient temperature. The impact of temperature on cell mechanics is not clearly understood. To explore the effect of temperature on cell mechanics, we employed magnetic tweezers to apply a force of 1 nN to 4.5 µm superparamagnetic beads. The beads were coated with fibronectin and coupled to human epithelial breast cancer cells, in particular MCF-7 and MDA-MB-231 cells. Cells were measured in a temperature range between 25 and 45 °C. The creep response of both cell types followed a weak power law. At all temperatures, the MDA-MB-231 cells were pronouncedly softer compared to the MCF-7 cells, whereas their fluidity was increased. However, with increasing temperature, the cells became significantly softer and more fluid. Since mechanical properties are manifested in the cell's cytoskeletal structure and the paramagnetic beads are coupled through cell surface receptors linked to cytoskeletal structures, such as actin and myosin filaments as well as microtubules, the cells were probed with pharmacological drugs impacting the actin filament polymerization, such as Latrunculin A, the myosin filaments, such as Blebbistatin, and the microtubules, such as Demecolcine, during the magnetic tweezer measurements in the specific temperature range. Irrespective of pharmacological interventions, the creep response of cells followed a weak power law at all temperatures. Inhibition of the actin polymerization resulted in increased softness in both cell types and decreased fluidity exclusively in MDA-MB-231 cells. Blebbistatin had an effect on the compliance of MDA-MB-231 cells at lower temperatures, which was minor on the compliance MCF-7 cells. Microtubule inhibition affected the fluidity of MCF-7 cells but did not have a significant effect on the compliance of MCF-7 and MDA-MB-231 cells. In summary, with increasing temperature, the cells became significant softer with specific differences between the investigated drugs and cell lines.

The Influence of Cold Atmospheric Pressure Plasma-Treated Media on the Cell Viability, Motility, and Induction of Apoptosis in Human Non-Metastatic (MCF7) and Metastatic (MDA-MB-231) Breast Cancer Cell Lines

Breast cancer remains the most common type of cancer, occurring in middle-aged women, and often leads to patients’ death. In this work, we applied a cold atmospheric pressure plasma (CAPP)-based reaction-discharge system, one that is unique in its class, for the production of CAPP-activated media (DMEM and Opti-MEM); it is intended for further uses in breast cancer treatment. To reach this aim, different volumes of DMEM or Opti-MEM were treated by CAPP. Prepared media were exposed to the CAPP treatment at seven different time intervals and examined in respect of their impact on cell viability and motility, and the induction of the apoptosis in human non-metastatic (MCF7) and metastatic (MDA-MB-231) breast cancer cell lines. As a control, the influence of CAPP-activated media on the viability and motility, and the type of the cell death of the non-cancerous human normal MCF10A cell line, was estimated. Additionally, qualitative and quantitative analyses of the reactive oxygen and nitrogen species (RONS), generated during the CAPP operation in contact with analyzed media, were performed. Based on the conducted research, it was found that 180 s (media activation time by CAPP) should be considered as the minimal toxic dose, which significantly decreases the cell viability and the migration of MDA-MB-231 cells, and also disturbs life processes of MCF7 cells. Finally, CAPP-activated media led to the apoptosis of analyzed cell lines, especially of the metastatic MDA-MB-231 cell line. Therefore, the application of the CAPP system may be potentially applied as a therapeutic strategy for the management of highly metastatic human breast cancer.

Multiple local therapeutics based on nano-hydrogel composites in breast cancer treatment

The locoregional recurrence of breast cancer after tumor resection represents several clinical challenges, and conventional post-surgical adjuvant therapeutics always bring about significant systemic side effects. Thus, the local therapy strategy has received considerable interest in breast cancer treatment, and hydrogels can function as ideal platforms due to their remarkable properties such as good biocompatibility, biodegradability, flexibility, and multifunctionality. The nano-hydrogel composites can further incorporate the advantages of nanomaterials into the hydrogel system, to fabricate hierarchical structures for stimulating controlled multi-stage release of different therapeutic agents and improving the synergistic effects of combination therapy. In this review, the problems of clinical treatments of breast cancer and properties of hydrogels in current biomedical applications are briefly overviewed. The focus is on recent advances in local therapy based on nano-hydrogel composites for both monotherapy (chemotherapy, photothermal and photodynamic therapy) and combination therapy (dual chemotherapy, photothermal chemotherapy, photothermal immunotherapy, radio-chemotherapy). Moreover, the challenges and perspectives in the development of advanced nano-hydrogel systems are also discussed.

DnaJA4 is involved in responses to hyperthermia by regulating the expression of F-actin in HaCaT cells

Background

Hyperthermia in combination with DnaJA4-knockout (KO) obviously affects the anti-viral immunity of HaCaT cells. The mechanisms of this process are not yet fully explored. However, it is known that DnaJA4 interacts with actin cytoskeleton after hyperthermia. Our aim was to investigate the effects of DnaJA4 on F-actin in HaCaT cells following hyperthermia.

Methods

Wild-type (WT) and DnaJA4-KO HaCaT cells were isolated at either 37°C (unheated) or 44°C (hyperthermia) for 30 min followed by testing under conditions of 37°C and assessing at 6, 12, and 24 h after hyperthermia. The cytoskeleton was observed with immunofluorescence. Flow cytometry and Western blotting were used to detect the expression of F-actin and relevant pathway protein.

Results

DnaJA4-KO and hyperthermia changed the cytoskeleton morphology of HaCaT cells. F-actin expression levels were elevated in DnaJA4-KO cells compared with WT cells (6364.33 ± 989.10 vs. 4272.67 ± 918.50, P < 0.05). In response to hyperthermia, F-actin expression levels of both WT and DnaJA4-KO cells showed a tendency to decrease followed by an obvious recovery after hyperthermia (WT cells: unheated vs. 6 h after hyperthermia or 24 h after hyperthermia: 0.34 ± 0.02 vs. 0.24 ± 0.01, 0.31 ± 0.01, P < 0.001, P < 0.05; DnaJA4-KO cells: unheated vs. 6 h after hyperthermia or 24 h after hyperthermia: 0.44 ± 0.01 vs. 0.30 ± 0.01, 0.51 ± 0.02, P < 0.001, P < 0.01). WT cells restored to baseline levels observed in the unheated condition, while DnaJA4-KO cells exceeded baseline levels in the recovery. As the upstream factors of F-actin, a similar profile in rho-associated serine/threonine kinase 1 (ROCK 1) and RhoA expressions was observed after hyperthermia. While E-cadherin expression was decreased in response to hyperthermia, it was increased in DnaJA4-KO cells compared with WT cells.

Conclusions

Hyperthermia affects the expression levels of F-actin in HaCaT cells. DnaJA4 knockout increases the expression of F-actin in HaCaT cells after hyperthermia. DnaJA4 regulates the expressions of F-actin and the related pathway proteins in response to hyperthermia in HaCaT cells.

Heat shock response regulates stimulus-specificity and sensitivity of the pro-inflammatory NF-κB signalling

BACKGROUND

Ability to adapt to temperature changes trough the Heat Shock Response (HSR) pathways is one of the most fundamental and clinically relevant cellular response systems. Heat Shock (HS) affects the signalling and gene expression responses of the Nuclear Factor κB (NF-κB) transcription factor, a critical regulator of proliferation and inflammation, however, our quantitative understanding of how cells sense and adapt to temperature changes is limited.

METHODS

We used live-cell time-lapse microscopy and mathematical modelling to understand the signalling of the NF-κB system in the human MCF7 breast adenocarcinoma cells in response to pro-inflammatory Interleukin 1β (IL1β) and Tumour Necrosis Factor α (TNFα) cytokines, following exposure to a 37-43 °C range of physiological and clinical temperatures.

RESULTS

We show that exposure to 43 °C 1 h HS inhibits the immediate NF-κB signalling response to TNFα and IL1β stimulation although uptake of cytokines is not impaired. Within 4 h after HS treatment IL1β-induced NF-κB responses return to normal levels, but the recovery of the TNFα-induced responses is still affected. Using siRNA knock-down of Heat Shock Factor 1 (HSF1) we show that this stimulus-specificity is conferred via the Inhibitory κB kinase (IKK) signalosome where HSF1-dependent feedback regulates TNFα, but not IL1β-mediated IKK recovery post HS. Furthermore, we demonstrate that through the temperature-dependent denaturation and recovery of IKK, TNFα and IL1β-mediated signalling exhibit different temperature sensitivity and adaptation to repeated HS when exposed to a 37-43 °C temperature range. Specifically, IL1β-mediated NF-κB responses are more robust to temperature changes in comparison to those induced by TNFα treatment.

CONCLUSIONS

We demonstrate that the kinetics of the NF-κB system following temperature stress is cytokine specific and exhibit differential adaptation to temperature changes. We propose that this differential temperature sensitivity is mediated via the IKK signalosome, which acts as a bona fide temperature sensor trough the HSR cross-talk. This novel quantitative understanding of NF-κB and HSR interactions is fundamentally important for the potential optimization of therapeutic hyperthermia protocols. Video Abstract.

Differences of the Immune Phenotype of Breast Cancer Cells after Ex Vivo Hyperthermia by Warm-Water or Microwave Radiation in a Closed-Loop System Alone or in Combination with Radiotherapy

The treatment of breast cancer by radiotherapy can be complemented by hyperthermia. Little is known about how the immune phenotype of tumor cells is changed thereby, also in terms of a dependence on the heating method. We developed a sterile closed-loop system, using either a warm-water bath or a microwave at 2.45 GHz to examine the impact of ex vivo hyperthermia on cell death, the release of HSP70, and the expression of immune checkpoint molecules (ICMs) on MCF-7 and MDA-MB-231 breast cancer cells by multicolor flow cytometry and ELISA. Heating was performed between 39 and 44 °C. Numerical process simulations identified temperature distributions. Additionally, irradiation with 2 × 5 Gy or 5 × 2 Gy was applied. We observed a release of HSP70 after hyperthermia at all examined temperatures and independently of the heating method, but microwave heating was more effective in cell killing, and microwave heating with and without radiotherapy increased subsequent HSP70 concentrations. Adding hyperthermia to radiotherapy, dynamically or individually, affected the expression of the ICM PD-L1, PD-L2, HVEM, ICOS-L, CD137-L, OX40-L, CD27-L, and EGFR on breast cancer cells. Well-characterized pre-clinical heating systems are mandatory to screen the immune phenotype of tumor cells in clinically relevant settings to define immune matrices for therapy adaption.

Triple-Negative Breast Cancer: A Review of Conventional and Advanced Therapeutic Strategies

Triple-negative breast cancer (TNBC) cells are deficient in estrogen, progesterone and ERBB2 receptor expression, presenting a particularly challenging therapeutic target due to their highly invasive nature and relatively low response to therapeutics. There is an absence of specific treatment strategies for this tumor subgroup, and hence TNBC is managed with conventional therapeutics, often leading to systemic relapse. In terms of histology and transcription profile these cancers have similarities to BRCA-1-linked breast cancers, and it is hypothesized that BRCA1 pathway is non-functional in this type of breast cancer. In this review article, we discuss the different receptors expressed by TNBC as well as the diversity of different signaling pathways targeted by TNBC therapeutics, for example, Notch, Hedgehog, Wnt/b-Catenin as well as TGF-beta signaling pathways. Additionally, many epidermal growth factor receptor (EGFR), poly (ADP-ribose) polymerase (PARP) and mammalian target of rapamycin (mTOR) inhibitors effectively inhibit the TNBCs, but they face challenges of either resistance to drugs or relapse. The resistance of TNBC to conventional therapeutic agents has helped in the advancement of advanced TNBC therapeutic approaches including hyperthermia, photodynamic therapy, as well as nanomedicine-based targeted therapeutics of drugs, miRNA, siRNA, and aptamers, which will also be discussed. Artificial intelligence is another tool that is presented to enhance the diagnosis of TNBC.

Injectable magnetic supramolecular hydrogel with magnetocaloric liquid-conformal property prevents post-operative recurrence in a breast cancer model

Locoregional recurrence of breast cancer after tumor resection represents several clinical challenges. Here, we demonstrate that co-delivery of chemotherapy and thermotherapeutic agents by a magnetic supramolecular hydrogel (MSH) following tumor resection prevents tumor recurrence in a breast cancer mouse model. The self-assembled MSH was designed through the partial inclusion complexation associated with the threading of α-CD on the copolymer moieties on the surface of the PEGylated iron oxide (Fe₃O₄) nanoparticles, which enables shear-thinning injection and controllable thermoreversible gel-sol transition. MSH was injected to the postoperative wound uniformly, which became mobile and perfect match with irregular cavity without blind angle due to the magnetocaloric gel-sol transition when exposed to alternating current magnetic field (ACMF). The magnetic nanoparticle-mediated induction heat during the gel-sol transition process caused the triggered release of dual-encapsulated chemotherapeutic drugs and provided an effect of thermally induced cell damage. The hierarchical structure of the MSH ensured that both hydrophobic and hydrophilic drugs can be loaded and consecutively delivered with different release curves. The hydrogel nanocomposite might provide a potential locally therapeutic approach for the precise treatment of locoregional recurrence of cancer.

STATEMENT OF SIGNIFICANCE

Tumor recurrence after resection represents several clinical challenges. In this study, we prepared shear-thinning injectable magnetic supramolecular hydrogel (MSH) and demonstrated their therapeutic applications in preventing the post-operative recurrence of breast cancer with facile synthesis and minimally invasive implantation in vivo. MSH was injected to the postoperative wound uniformly, which become mobile and perfect match with irregular cavity without blind angle through magnetocaloric gel-sol transition when exposed to ACMF. The magnetic nanoparticles mediated induction heat during the gel-sol transition process caused the triggered release of dual-encapsulated chemotherapeutic drugs as well as thermally induced cell damage. This study demonstrates that MSH with the controlled administration of combined thermo-chemotherapy exhibit great superiority in terms of preventing post-operation cancer relapse.

DNAJA4 deficiency enhances NF-kappa B-related growth arrest induced by hyperthermia in human keratinocytes

BACKGROUND

Hyperthermia is an effective treatment against cancer and human papillomavirus (HPV) infection. Previous studies have shown that heat shock proteins are crucial to the action of hyperthermia.

OBJECTIVES

To examine the effects of hyperthermia in combination with DNAJA4-deficiency on human keratinocytes and Condyloma acumunatum (CA) tissues.

METHODS

HaCaT cells were subjected to 44°C (compared to 37°C) waterbath for 30min for stimulation. Foreskin or CA tissues obtained from patients undergoing circumcision or pathological examination were bisected and subjected to similar treatments. DNAJA4-knockout (KO) HaCaT cells were generated with CRISPR/Cas9 technology. mRNA and protein expressions were determined using rt-qPCR and western-blotting. Cell cycle distribution, apoptosis and senescence were analyzed by flow cytometry.

RESULTS

DNAJA4 was induced in HaCaT cells, foreskin and CA tissues subjected to hyperthermia at both transcriptional and translational levels. NF-kB,³ was activated by hyperthermia in HaCaT cells, and further enhanced by DNAJA4-deficiency. Transcription of TNF-α⁴; IL-1B,⁵ TNFAIP3⁶ and IL-8⁷ were induced in HaCaT cells subjected to hyperthermia. DNAJA4-knockout promoted transcriptions of TNF-α and IL-1B, whereas decreased that of TNFAIP3 and IL-8. Reduced cell survival, proliferation and viability were demonstrated using flow cytometry and MTS assays. Furthermore, NF-kB inhibitors reversed most of the phenotypes observed.

CONCLUSIONS

Hyperthermia reduced HaCaT cell proliferation and promoted cytokine expressions responsible for anti-viral activity, mainly through a NF-kB dependent pathway. DNAJA4-deficiency enhanced the activation of NF-kB by hyperthermia in HaCaT cells, indicating that DNAJA4 may be a promising therapeutic target for use in the treatment of cutaneous HPV infections.