Hyperthermia-mediated drug delivery induces biological effects at the tumor and molecular levels that improve cisplatin efficacy in triple negative breast cancer

Nanoscale strides: exploring innovative therapies for breast cancer treatment

Breast cancer (BC) is a predominant malignancy in women that constitutes approximately 30% of all cancer cases and has a mortality rate of 14% in recent years. The prevailing therapies include surgery, chemotherapy, and radiotherapy, each with its own limitations and challenges. Despite oral or intravenous administration, there are numerous barriers to accessing anti-BC agents before they reach the tumor site, including physical, physiological, and biophysical barriers. The complexity of BC pathogenesis, attributed to a combination of endogenous, chronic, intrinsic, extrinsic and genetic factors, further complicates its management. Due to the limitations of existing cancer treatment approaches, there is a need to explore novel, efficacious solutions. Nanodrug delivery has emerged as a promising avenue in cancer chemotherapy, aiming to enhance drug bioavailability while mitigating adverse effects. In contrast to conventional chemotherapy, cancer nanotechnology leverages improved permeability to achieve comprehensive disruption of cancer cells. This approach also presented superior pharmacokinetic profiles. The application of nanotechnology in cancer therapeutics includes nanotechnological tools, but a comprehensive review cannot cover all facets. Thus, this review concentrates specifically on BC treatment. The focus lies in the successful implementation of systematic nanotherapeutic strategies, demonstrating their superiority over conventional methods in delivering anti-BC agents. Nanotechnology-driven drug delivery holds immense potential in treating BC. By surmounting multiple barriers and capitalizing on improved permeability, nanodrug delivery has demonstrated enhanced efficacy and reduced adverse effects compared to conventional therapies. This review highlights the significance of systematic nanotherapy approaches, emphasizing the evolving landscape of BC management.

Determining the maximum tolerated dose of paclitaxel combined with fixed dose of cisplatin for hyperthermic intraperitoneal chemotherapy in ovarian cancer: A multicenter phase I trial

OBJECTIVE

To determine the maximum tolerated dose (MTD) of paclitaxel combined with a fixed dose of cisplatin (75 mg/m2) delivered via hyperthermic intraperitoneal chemotherapy (HIPEC) to patients with ovarian cancer.

METHODS

This multicenter Phase I trial employed a Bayesian Optimal Interval (BOIN) design. The MTD was determined to have a target dose-limiting toxicity (DLT) rate of 25%. The starting dose was 175 mg/m2. The Data and Safety Monitoring Board made decisions regarding dose escalation or de-escalation in increments of 25 mg/m2 for subsequent patient cohorts, up to a maximum sample size of 30 or 12 patients treated at a given dose.

RESULTS

Twenty-one patients participated in this study. Among the three evaluable patients who received 150 mg/m2 paclitaxel, no DLTs were observed. Among the 12 evaluable patients who received 175 mg/m2 paclitaxel, two reported DLTs: one had grade 4 neutropenia and one had grade 4 anemia, neutropenia, and leukopenia. Four of the six evaluable patients who received 200 mg/m2 paclitaxel reported DLTs: one patient had grade 4 diarrhea, one had grade 3 kidney injury, and two had grade 4 anemia. The isotonic estimate of the DLT rate in the 175 mg/m2 dose group was 0.17 (95% confidence interval, 0.02-0.42), and this dose was selected as the MTD.

CONCLUSION

Paclitaxel, when combined with a fixed dose of cisplatin (75 mg/m2), can be safely administered intraperitoneally at a dose of 175 mg/m2 in patients with ovarian cancer who received HIPEC (43 °C, 90 min) following cytoreductive surgery.

Liposomal Nano-Based Drug Delivery Systems for Breast Cancer Therapy: Recent Advances and Progresses

Breast cancer is a highly prevalent disease on a global scale, with a 30% incidence rate among women and a 14% mortality rate. Developing countries bear a disproportionate share of the disease burden, while countries with greater technological advancements exhibit a higher incidence. A mere 7% of women under the age of 40 are diagnosed with breast cancer, and the prevalence of this ailment is significantly diminished among those aged 35 and younger. Chemotherapy, radiation therapy, and surgical intervention comprise the treatment protocol. However, the ongoing quest for a definitive cure for breast cancer continues. The propensity for cancer stem cells to metastasize and resistance to treatment constitute their Achilles' heel. The advancement of drug delivery techniques that target cancer cells specifically holds significant promise in terms of facilitating timely detection and effective intervention. Novel approaches to pharmaceutical delivery, including nanostructures and liposomes, may bring about substantial changes in the way breast cancer is managed. These systems offer a multitude of advantages, such as heightened bioavailability, enhanced solubility, targeted tumor destruction, and diminished adverse effects. The application of nano-drug delivery systems to administer anti-breast cancer medications is a significant subject of research. This article delves into the domain of breast cancer, conventional treatment methods, the incorporation of nanotechnology into managerial tactics, and strategic approaches aimed at tackling the disease at its core.

Hyperthermic Intraperitoneal Chemotherapy After Interval Cytoreductive Surgery for Patients With Advanced-Stage Ovarian Cancer Who Had Received Neoadjuvant Chemotherapy

Importance

Hyperthermic intraperitoneal chemotherapy (HIPEC) followed by interval cytoreductive surgery (ICS) has shown survival benefits for patients with advanced-stage ovarian cancer. However, there is still a lack of consensus regarding the integration of HIPEC into clinical practice.

Objective

To evaluate the safety and effectiveness of ICS with HIPEC compared with ICS alone in clinical practice for patients with advanced-stage ovarian cancer.

Design, Setting, and Participants

This prospective, multicenter, comparative effectiveness cohort study enrolled 205 patients with stage III or IV ovarian cancer who had received at least 3 cycles of neoadjuvant chemotherapy followed by ICS with HIPEC or ICS without HIPEC at 7 Korean Gynecologic Oncology Group institutions between September 1, 2017, and April 22, 2022. Nine patients were excluded because they did not meet the inclusion criteria.

Exposures

Neoadjuvant chemotherapy followed by ICS with HIPEC or ICS without HIPEC.

Main Outcomes and Measures

The primary end point was progression-free survival (PFS). Overall survival (OS) and the safety profile were the key secondary end points.

Results

This study included 196 patients (median age, 58.0 years [range, 38-82 years]), of whom 109 underwent ICS with HIPEC and 87 underwent ICS without HIPEC. The median duration of follow-up was 28.2 months (range, 3.5-58.6 months). Disease recurrence occurred in 128 patients (65.3%), and 30 patients (15.3%) died. Interval cytoreductive surgery with HIPEC was associated with a significant improvement in median PFS compared with ICS without HIPEC (22.9 months [95% CI, 3.5-58.6 months] vs 14.2 months [95% CI, 4.0-56.2 months]; P = .005) and median OS (not reached [95% CI, 3.5 months to not reached] vs 53.0 [95% CI, 4.6-56.2 months]; P = .002). The frequency of grade 3 or 4 postoperative complications was similar in both groups (ICS with HIPEC, 3 of 109 [2.8%] vs ICS without HIPEC, 3 of 87 [3.4%]; P > .99). Among patients with recurrence, the frequency of peritoneal recurrence was lower in the ICS with HIPEC group than in the ICS without HIPEC group (21 of 64 [32.8%] vs 41 of 64 [64.1%]; P = .001).

Conclusions and Relevance

This study suggests that ICS in conjunction with HIPEC was associated with longer PFS and OS than ICS without HIPEC for patients with advanced-stage ovarian cancer and was not associated with higher rates of postoperative complications. The lower rate of peritoneal recurrence after HIPEC may be associated with improved OS.

Valproic acid reprograms the metabolic aberration of cisplatin treatment via ALDH modulation in triple-negative breast cancer cells

We recently demonstrated that the histone deacetylase inhibitor valproic acid (VPA) reprograms the cisplatin-induced metabolome of triple-negative breast cancer (TNBC) cells, including a shift in hexose levels. Accordingly, here, we tested the hypothesis that VPA alters glucose metabolism in correlation with cisplatin sensitivity. Two TNBC cell lines, MDA-MB-231 (a cisplatin-resistant line) and MDA-MB-436 (a cisplatin-sensitive line), were analyzed. The glycolysis and oxidative metabolism were measured using the Glycolysis Stress Test kit. The expression of aldehyde dehydrogenases (ALDHs), enzymes linked to drug resistance, was investigated by Western blot and real-time PCR analyses. We additionally studied the influence of ALDH inhibition by disulfiram on the viability of MDA-MB-231 cells and on a TNBC patient-derived organoid system. Cisplatin treatment reduced the extracellular acidification rate in MDA-MB-436 cells but not MDA-MB-231 cells, whereas VPA addition increased the extracellular acidification rate in both cell lines. VPA further reduced the oxygen consumption rate of cisplatin-treated MDA-MB-436 cells, which correlated with cell cycle alterations. However, in MDA-MB-231 cells, the cell cycle distribution did not change between cisplatin/VPA-cisplatin treatments. In both cell lines, VPA increased the expression of ALDH isoform and ALDH1A1 expression. However, only in MDA-MB-231 cells, VPA synergized with cisplatin to augment this effect. Disulfiram sensitized the cells to the cytotoxic effects of the VPA-cisplatin combination. Furthermore, the disulfiram-VPA-chemotherapy combination was most effective in TNBC organoids. Our results show that ALDH overexpression may act as one mechanism of cellular resistance to VPA in TNBC and that its inhibition may enhance the therapeutic efficacy of VPA-chemotherapeutic drug combinations.

Research progress of hyperthermia in tumor therapy by influencing metabolic reprogramming of tumor cells

Cellular metabolic reprogramming is an important feature of malignant tumors. Metabolic reprogramming causes changes in the levels or types of specific metabolites inside and outside the cell, which affects tumorigenesis and progression by influencing gene expression, the cellular state, and the tumor microenvironment. During tumorigenesis, a series of changes in the glucose metabolism, fatty acid metabolism, amino acid metabolism, and cholesterol metabolism of tumor cells occur, which are involved in the process of cellular carcinogenesis and constitute part of the underlying mechanisms of tumor formation. Hyperthermia, as one of the main therapeutic tools for malignant tumors, has obvious effects on tumor cell metabolism. In this paper, we will combine the latest research progress in the field of cellular metabolic reprogramming and focus on the current experimental research and clinical treatment of hyperthermia in cellular metabolic reprogramming to discuss the feasibility of cellular metabolic reprogramming-related mechanisms guiding hyperthermia in malignant tumor treatment, so as to provide more ideas for hyperthermia to treat malignant tumors through the direction of cellular metabolic reprogramming.

Photoactivated HPPH-Liposomal therapy for the treatment of HPV-Negative head and neck cancer

OBJECTIVES

Human Papillomavirus (HPV)-negative head and neck cancer (HNC) is an aggressive malignancy with a poor prognosis. To improve outcomes, we developed a novel liposomal targeting system embedded with 2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a (HPPH), a chlorin-based photosensitizer. Upon exposure to 660 nm light, HPPH phototriggering generates reactive oxygen species. The objective of this study was to evaluate biodistribution and test efficacy of HPPH-liposomal therapy in a patient-derived xenograft (PDX) model of chemoradioresistant HNC.

MATERIALS AND METHODS

PDX models were developed from two surgically resected HNCs (P033 and P038) recurrent after chemoradiation. HPPH-liposomes were created including trace amounts of DiR (Ex/Em 785/830 nm), a near infrared lipid probe. Liposomes were injected via tail vein into PDX models. Biodistribution was assessed at serial timepoints in tumor and end-organs through in vivo DiR fluorescence. To evaluate efficacy, tumors were treated with a cw-diode 660 nm laser (90 mW/cm2, 5 min). This experimental arm was compared to appropriate controls, including HPPH-liposomes without laser or vehicle with laser alone.

RESULTS

HPPH-liposomes delivered via tail vein exhibited selective tumor penetration, with a peak concentration at 4 h. No systemic toxicity was observed. Treatment with combined HPPH-liposomes and laser resulted in improved tumor control relative to either vehicle or laser alone. Histologically, this manifested as both increased cellular necrosis and decreased Ki-67 staining in the tumors treated with combined therapy.

CONCLUSIONS

These data demonstrate tumor-specific anti-neoplastic efficacy of HPPH-liposomal treatment for HNC. Importantly, this platform can be leveraged in future studies for targeted delivery of immunotherapies which can be packaged within HPPH-liposomes.

A Clinically Translatable Ternary Platinum(IV) Prodrug for Synergistically Reversing Drug Resistance

Scalable production of a clinically translatable formulation with enhanced therapeutic efficacy against cisplatin-resistant tumors without the use of any clinically unapproved reagents and additional manipulation remains a challenge. For this purpose, we report herein the construction of TPP-Pt-acetal-CA based on all commercially available, clinically approved reagents consisting of a cinnamaldehyde (CA) unit for reactive oxygen species generation, a mitochondrially targeted triphenylphosphonium (TPP)-modified Pt(IV) moiety for mitochondrial dysfunction, and an intracellular acidic pH-cleavable acetal link between these two moieties. The resulting self-assembled, stabilized TPP-Pt-acetal-CA nanoparticles mediated an IC₅₀ value approximately 6-fold lower than that of cisplatin in A549/DDP cells and a tumor weight reduction 3.6-fold greater than that of cisplatin in A549/DDP tumor-bearing BALB/c mice with insignificant systematic toxicity due to the synergistic mitochondrial dysfunction and markedly amplified oxidative stress. Therefore, this study presents the first example of a clinically translatable Pt(IV) prodrug with enhanced efficiency for synergistically reversing drug resistance.

Changing Surface Polyethylene Glycol Architecture Affects Elongated Nanoparticle Penetration into Multicellular Tumor Spheroids

Nanoparticles (NPs) designed for biomedical applications are coated with protein-repellent polymers. Here, we examine the penetration of rodlike NPs with narrow size distributions (L_n = 170 nm, w_n = 12 nm) into multicellular tumor spheroids prepared from two human cancer cell lines. Two types of NPs with different core materials [polyferrocenylsilane and cellulose nanocrystals (CNC)] were coated with a dense brush of poly(oligoethyleneglycol methacrylate) (POEGMA), while a second CNC NP sample was coated with a linear polyethylene glycol (PEG) brush. While the core material had little influence, the coating material was strikingly important, with POEGMA-coated NPs penetrating much more deeply into the tumor spheroids than the NPs coated with linear PEG. Localization experiments using ¹¹¹In-labeled POEGMA-coated CNC NPs showed that most of the radioactivity remained in the interstitial space (ca. 78%) with little cell uptake (ca. 6%). Hence, the deep penetration of these nanorods into tumor spheroids is associated with an interstitial diffusion pathway through the extracellular matrix and not cellular transcytosis.

Effect of HIPEC according to HRD/BRCAwt genomic profile in stage III ovarian cancer - results from the phase III OVHIPEC trial

The addition of hyperthermic intraperitoneal chemotherapy (HIPEC) with cisplatin to interval cytoreductive surgery improves recurrence-free (RFS) and overall survival (OS) in patients with stage III ovarian cancer. Homologous recombination deficient (HRD) ovarian tumors are usually more platinum sensitive. Since hyperthermia impairs BRCA1/2 protein function, we hypothesized that HRD tumors respond best to treatment with HIPEC. We analyzed the effect of HIPEC in patients in the OVHIPEC trial, stratified by HRD status and BRCAm status. Clinical data and tissue samples were collected from patients included in the randomized, phase III OVHIPEC-1 trial. DNA copy number variation (CNV) profiles, HRD-related pathogenic mutations, and BRCA1 promotor hypermethylation were determined. CNV-profiles were categorized as HRD or non-HRD, based on a previously validated algorithm-based BRCA1-like classifier. Hazard ratios (HR) and corresponding 99% confidence intervals (CI) for the effect of RFS and OS of HIPEC in the BRCAm, the HRD/BRCAwt and the non-HRD group were estimated using Cox proportional hazard models. DNA was available from 200/245 (82%) patients. Seventeen (9%) tumors carried a pathogenic mutation in BRCA1 and 14 (7%) in BRCA2. Ninety-one (46%) tumors classified as BRCA1-like. The effect of HIPEC on RFS and OS was absent in BRCAm tumors (HR 1.25; 99%CI 0.48-3.29), and most present in HRD/BRCAwt (HR 0.44; 99%CI 0.21-0.91), and non-HRD/BRCAwt tumors (HR 0.82; 99%CI 0.48-1.42), interaction p-value: 0.024. Patients with HRD tumors without pathogenic BRCA1/2 mutation appear to benefit most from treatment with HIPEC, while benefit in patients with BRCA1/2 pathogenic mutations and patients without HRD seems less evident.

Targeted nanomedicine in cisplatin-based cancer therapeutics

Since its license in 1978, cisplatin has proved to be one of the most successful chemotherapeutic agents in the world. However, two acute challenges facing cisplatin, resistance and toxicity, have resulted in a bottleneck of clinical application. Targeted nanomedicine shows great promise in delivering cisplatin for maximizing efficacy while minimizing off-target toxicity. This article surveyed the recent progress and challenges of targeted nanomedicine in managing resistance and toxicity of cisplatin in both fundamental and clinical aspects. Particularly, we focused on three major mechanisms counteracting cisplatin sensitivity (decreased intracellular accumulation, increased cisplatin deactivation, and enhanced DNA repair/translesion synthesis) and correspondingly highlighted a few representative approaches to increase cisplatin sensitivity through improving the intracellular concentration of cisplatin and implementing combination therapy. Moreover, the requirements for future advancements in cisplatin delivery systems are rendered with emphasis on (i) understanding of nano-bio interaction and post-accumulation biological effects instead of overwhelmingly improving tumor accumulation, (ii) development of stimuli-responsive and/or actively-targeted nanomedicines, (iii) optimization of combination therapy, (iv) novel combinations targeting tumor microenvironment and immunotherapy. We postulate that cisplatin-based nanomedicines will continuously advance and potentially revolutionize oncological treatment.

Whole-body hyperthermia combined with chemotherapy and intensity-modulated radiotherapy for treatment of advanced nasopharyngeal carcinoma: a retrospective study with propensity score matching

BACKGROUND

Several studies have reported the combination of intracavity or cervical lymph node hyperthermia with chemoradiotherapy (CRT) to improve clinical outcomes in nasopharyngeal carcinoma (NPC), but the combination with whole-body hyperthermia (WBH) for treating NPC is unexplored. We aimed to assess the efficacy of the combination of radiotherapy, chemotherapy and WBH in patients with locoregionally advanced NPC.

METHODS

Between July 2008 and November 2012, 239 newly diagnosed NPC patients were enrolled in a pre-propensity score-matched cohort, including 193 patients who received CRT (CRT group) and 46 who underwent CRT with WBH (HCRT group). The feasibility and clinical outcomes of both groups were evaluated and toxicities assessed. Survival rates were assessed using the Kaplan-Meier method, log-rank test and Cox regression.

RESULTS

Following propensity score matching, 46 patients from each group were included. The 5-year overall survival (OS) rates were 65.2% in the CRT group and 80.3% in the HCRT group (p=.027). In contrast, the other survival outcomes at 5 years were similar between the groups: locoregional recurrence-free survival (LRRFS), 74.7% vs. 87.6% (p=.152); distant metastasis-free survival (DMFS), 67.4% vs. 77.9% (p=.125); and progression-free survival (PFS), 53.1% vs. 69.2% (p=.115). In the multivariate analyses, the only two independent predictors of OS were clinical stage and HCRT.

CONCLUSIONS

These results suggest that WBH, when combined with CRT, can improve the OS of patients with advanced NPC.

Image-Guided Peri-Tumoral Radiofrequency Hyperthermia-Enhanced Direct Chemo-Destruction of Hepatic Tumor Margins

Purpose

To validate the feasibility of using peri-tumoral radiofrequency hyperthermia (RFH)-enhanced chemotherapy to obliterate hepatic tumor margins.

Method and Materials

This study included in vitro experiments with VX2 tumor cells and in vivo validation experiments using rabbit models of liver VX2 tumors. Both in vitro and in vivo experiments received different treatments in four groups (n=6/group): (i) RFH-enhanced chemotherapy consisting of peri-tumoral injection of doxorubicin plus RFH at 42°C; (ii) RFH alone; (iii) doxorubicin alone; and (iv) saline. Therapeutic effect on cells was evaluated using different laboratory examinations. For in vivo experiments, orthotopic hepatic VX2 tumors in 24 rabbits were treated by using a multipolar radiofrequency ablation electrode, enabling simultaneous delivery of both doxorubicin and RFH within the tumor margins. Ultrasound imaging was used to follow tumor growth overtime, correlated with subsequent histopathological analysis.

Results

In in vitro experiments, MTS assay demonstrated the lowest cell proliferation, and apoptosis analysis showed the highest apoptotic index with RFH-enhanced chemotherapy, compared with the other three groups (p<0.01). In in vivo experiments, ultrasound imaging detected the smallest relative tumor volume with RFH-enhanced chemotherapy (p<0.01). The TUNEL assay further confirmed the significantly increased apoptotic index and decreased cell proliferation in the RFH-enhanced therapy group (p<0.01).

Conclusion

This study demonstrates that peri-tumoral RFH can specifically enhance the destruction of tumor margins in combination with peri-tumoral injection of a chemotherapeutic agent. This new interventional oncology technique may address the critical clinical problem of frequent marginal tumor recurrence/persistence following thermal ablation of large (>3 cm) hepatic cancers.

Heat-activated nanomedicine formulation improves the anticancer potential of the HSP90 inhibitor luminespib in vitro

The heat shock protein 90 inhibitor, luminespib, has demonstrated potent preclinical activity against numerous cancers. However, clinical translation has been impeded by dose-limiting toxicities that have necessitated dosing schedules which have reduced therapeutic efficacy. As such, luminespib is a prime candidate for reformulation using advanced drug delivery strategies that improve tumor delivery efficiency and limit off-target side effects. Specifically, thermosensitive liposomes are proposed as a drug delivery strategy capable of delivering high concentrations of drug to the tumor in combination with other chemotherapeutic molecules. Indeed, this work establishes that luminespib exhibits synergistic activity in lung cancer in combination with standard of care drugs such as cisplatin and vinorelbine. While our research team has previously developed thermosensitive liposomes containing cisplatin or vinorelbine, this work presents the first liposomal formulation of luminespib. The physico-chemical properties and heat-triggered release of the formulation were characterized. Cytotoxicity assays were used to determine the optimal drug ratios for treatment of luminespib in combination with cisplatin or vinorelbine in non-small cell lung cancer cells. The formulation and drug combination work presented in this paper offer the potential for resuscitation of the clinical prospects of a promising anticancer agent.

Closed-loop trans-skull ultrasound hyperthermia leads to improved drug delivery from thermosensitive drugs and promotes changes in vascular transport dynamics in brain tumors

Effective drug delivery in brain tumors remains a major challenge in oncology. Although local hyperthermia and stimuli-responsive delivery systems, such as thermosensitive liposomes, represent promising strategies to locally enhance drug delivery in solid tumors and improve outcomes, their application in intracranial malignancies remains unexplored. We hypothesized that the combined abilities of closed-loop trans-skull Magnetic Resonance Imaging guided Focused Ultrasound (MRgFUS) hyperthermia with those of thermosensitive drugs can alleviate challenges in drug delivery and improve survival in gliomas.

Methods: To conduct our investigations, we first designed a closed loop MR-guided Focused Ultrasound (MRgFUS) system for localized trans-skull hyperthermia (ΔT < 0.5 °C) in rodents and established safety thresholds in healthy mice. To assess the abilities of the developed system and proposed therapeutic strategy for FUS-triggered chemotherapy release we employed thermosensitive liposomal Dox (TSL-Dox) and tested it in two different glioma tumor models (F98 in rats and GL261 in mice). To quantify Dox delivery and changes in the transvascular transport dynamics in the tumor microenvironment we combined fluorescent microscopy, dynamic contrast enhanced MRI (DCE-MRI), and physiologically based pharmacokinetic (PBPK) modeling. Lastly, to assess the therapeutic efficacy of the system and of the proposed therapeutic strategy we performed a survival study in the GL261 glioma bearing mice.

Results: The developed closed-loop trans-skull MRgFUS-hyperthermia system that operated at 1.7 MHz, a frequency that maximized the brain (FUS-focus) to skull temperature ratio in mice, was able to attain and maintain the desired focal temperature within a narrow range. Histological evidence (H&E and Nissl) suggests that focal temperature at 41.5 ± 0.5 °C for 10 min is below the threshold for tissue damage. Quantitative analysis of doxorubicin delivery from TSLs with MRgFUS-hyperthermia demonstrated 3.5-fold improvement in cellular uptake in GL261 glioma mouse tumors (p < 0.001) and 5-fold increase in delivery in F98 glioma rat tumors (p < 0.05), as compared to controls (TSL-Dox-only). Moreover, PBPK modeling of drug transport that was calibrated using the experimental data indicated that thermal stress could lead to significant improvement in the transvascular transport (2.3-fold increase in the vessel diffusion coefficient; P < 0.001), in addition to promoting targeted Dox release. Prospective experimental investigations with DCE-MRI during FUS-hyperthermia, supported these findings and provided evidence that moderate thermal stress (≈41 °C for up to 10 min) can promote acute changes in the vascular transport dynamics in the brain tumor microenvironment (K^trans value for control vs. FUS was 0.0097 and 0.0148 min^-1, respectively; p = 0.026). Crucially, survival analysis demonstrated significant improvement in the survival in the TSL-Dox-FUS group as compared to TSL-Dox-only group (p < 0.05), providing supporting evidence on the therapeutic potential of the proposed strategy.

Conclusions: Our investigations demonstrated that spatially controlled thermal stress can be attained and sustained in the mouse brain, using a trans-skull closed-loop MRgFUS system, and used to promote the effective delivery of chemotherapy in gliomas from thermosensitive drugs. This system also allowed us to conduct mechanistic investigations that resulted in the refinement of our understanding on the role of thermal stress in augmenting mass and drug transport in brain tumors. Overall, our study established a new paradigm for effective drug delivery in brain tumors based on closed-loop ultrasound-mediated thermal stress and thermosensitive drugs.

Image-guided thermosensitive liposomes for focused ultrasound enhanced co-delivery of carboplatin and SN-38 against triple negative breast cancer in mice

Triggerable nanocarriers have the potential to significantly improve the therapeutic index of existing anticancer agents. They allow for highly localised delivery and release of therapeutic cargos, reducing off-target toxicity and increasing anti-tumour activity. Liposomes may be engineered to respond to an externally applied stimulus such as focused ultrasound (FUS). Here, we report the first co-delivery of SN-38 (irinotecan's super-active metabolite) and carboplatin, using an MRI-visible thermosensitive liposome (iTSL). MR contrast enhancement was achieved by the incorporation of a gadolinium lipid conjugate in the liposome bilayer along with a dye-labelled lipid for near infrared fluorescence bioimaging. The resulting iTSL were successfully loaded with SN-38 in the lipid bilayer and carboplatin in the aqueous core - allowing co-delivery of both. The iTSL demonstrated both thermosensitivity and MR-imageability. In addition, they showed effective local targeted co-delivery of carboplatin and SN-38 after triggered release with brief FUS treatments. A single dosage induced significant improvement of anti-tumour activity (over either the free drugs or the iTSL without FUS-activation) in triple negative breast cancer xenografts tumours in mice.

Investigating the influence of block copolymer micelle length on cellular uptake and penetration in a multicellular tumor spheroid model

The efficient penetration of drug nanocarriers into tumors is an important prerequisite for therapeutic and diagnostic success. The physicochemical properties of nanocarriers, including size, shape and surface chemistry have been shown to influence their transport in biological systems. Recent studies have shown that elongated nanoparticles (NPs) can exhibit advantageous properties in comparison to spherical NPs, but these experiments have involved a variety of different materials, many of which are characterized by a broad size distribution. Here we describe a series of rigid rod-like micelles of uniform width, with narrow length distributions, and common surface chemistry, and examine their cell uptake and penetration into multicellular tumor spheroids (MCTSs) formed from two human breast cancer cell lines (MDA-MB-436 and MDB-MB-231). These micelles were prepared from a polyferrocenylsilane (PFS) diblock copolymer (BCP) with a corona block consisting of a statistical polymer of aminopropyl methacrylamide and oligo(ethyleneglycol methacrylate) (PFS₂₇-b-PAPMA₃-stat-POEGMA₄₈). The rigid rod micelles, with a common width (12 nm) and lengths ranging from 80 to 2000 nm, were prepared by seeded growth crystallization-driven self-assembly in ethanol and then transferred to water. To consider whether changing the shape of these micelles affects its uptake and penetration behavior, analogous spherical micelles were prepared by direct nanoprecipitation into water. Both micelle shape and length were found to influence cellular uptake and penetration into 500 μm MCTSs. Laser confocal fluorescence microscopy was used to examine penetration of these micelles into three-dimensional MCTS up to 90 μm depth. Micelles with an elongated shape and short length (80 nm) demonstrated the deepest penetration into the MCTSs formed by MDA-MB-436 cells. Micelles with lengths of 200 nm also showed substantial penetration into these MCTS, but the extent and depth of tumor penetration of the rod-like micelles decreased with increasing aspect ratio. MCTS of MDA-MB-231 cells had a less dense, more open structure than those formed by MDA-MB-436 cells. Here more extensive penetration was observed, particularly for the longer micelle samples.

The Impact of [C16Pyr][Amp] on the Aggressiveness in Breast and Prostate Cancer Cell Lines

Breast (BrCa) and prostate (PCa) cancers are the most common malignancies in women and men, respectively. The available therapeutic options for these tumors are still not curative and have severe side effects. Therefore, there is an urgent need for more effective antineoplastic agents. Herein, BrCa, PCa, and benign cell lines were treated with two ionic liquids and two quinoxalines and functional experiments were performed-namely cell viability, apoptosis, cytotoxicity, and colony formation assays. At the molecular level, an array of gene expressions encompassing several molecular pathways were used to explore the impact of treatment on gene expression. Although both quinoxalines and the ionic liquid [C2OHMIM][Amp] did not show any effect on the BrCa and PCa cell lines, [C16Pyr][Amp] significantly decreased cell viability and colony formation ability, while it increased the apoptosis levels of all cell lines. Importantly, [C16Pyr][Amp] was found to be more selective for cancer cells and less toxic than cisplatin. At the molecular level, this ionic liquid was also associated with reduced expression levels of CPT2, LDHA, MCM2, and SKP2, in both BrCa and PCa cell lines. Hence, [C16Pyr][Amp] was shown to be a promising anticancer therapeutic agent for BrCa and PCa cell lines.

Adipose Mesenchymal Stem Cell-Derived Exosomal microRNA-1236 Reduces Resistance of Breast Cancer Cells to Cisplatin by Suppressing SLC9A1 and the Wnt/β-Catenin Signaling

BACKGROUND

Emerging evidence has noted the versatile functions of mesenchymal stem cell-derived exosomes (MSC-Exos) in cancer control. This work aims to probe to function of adipose MSC-Exos (adMSC-Exos) in drug-resistance of breast cancer (BC) cells to cisplatin (DDP) and the molecules involved.

METHODS

Parental and DDP-resistant BC cell lines MCF-7 and MDA-MB-231 were used. All cells were pre-treated with adMSC-Exos. Then, the viability and apoptosis of cells after DDP treatment were determined. Differentially expressed miRNAs after adMSC-exo treatment were screened out. Rescue experiments were conducted by pre-transfecting miR-1236 inhibitor into adMSCs, and the role of miR-1236 in DDP sensitivity was determined. Targeting mRNAs of miR-1236 were predicted by bioinformatics analysis. Altered SLC9A1 expression was administrated to evaluate its function in DDP resistance.

RESULTS

The adMSC-Exos notably increased the sensitivity of either parental or DDP-resistant BC cells to DDP. SLC9A1 was notably highly expressed in DDP-resistant cells but inhibited following adMSC-exo administration. Importantly, miR-1236, which could directly bind to SLC9A1 and suppress its expression, was confirmed as an enriched miRNA in adMSC-Exos. Either inhibition of miR-1236 or upregulation of SLC9A1 blocked the pro-sensitize roles of adMSC-Exos. In addition, the Wnt/β-catenin pathway activity was suppressed by adMSC-Exos but recovered by SLC9A1.

CONCLUSION

This study evidenced that adMSC-Exos carry miR-1236 to increase sensitivity of BC cells to DDP with the involvement of SLC9A1 downregulation and Wnt/β-catenin inactivation. This finding may offer novel insights into treatment for drug-resistant BC.

Novel fractionated ultrashort thermal exposures with MRI-guided focused ultrasound for treating tumors with thermosensitive drugs

Thermosensitive liposomes represent an important paradigm in oncology, where hyperthermia-mediated release coupled with thermal bioeffects enhance the effectiveness of chemotherapy. Their widespread clinical adoption hinges upon performing controlled targeted hyperthermia, and a leading candidate to achieve this is temperature-based magnetic resonance imaging (MRI)-guided focused ultrasound (MRgFUS). However, the current approach to hyperthermia involves exposures lasting tens of minutes to hours, which is not possible to achieve in many circumstances because of blood vessel cooling and respiratory motion. Here, we investigate a novel approach to overcome these limitations: to use fractionated ultrashort (~30 s) thermal exposures (~41° to 45°C) to release doxorubicin from a thermosensitive liposome. This is first demonstrated in a dorsal chamber tumor model using two-photon microscopy. Thermal exposures were then conducted with a rabbit tumor model using a custom MRgFUS system incorporating temperature feedback control. Drug release was confirmed, and longitudinal experiments demonstrated profoundly enhanced tumor growth inhibition and survival.

Long Non-Coding RNA UCA1 Modulates Paclitaxel Resistance in Breast Cancer via miR-613/CDK12 Axis

Background

Paclitaxel (PTX) occupies a considerable status in the chemotherapies of breast cancer (BC), but the drug resistance keeps an obstructive factor of PTX treatment. This study was designed to explore the molecular mechanism of long non-coding RNA (lncRNA) urothelial carcinoma-associated 1 (UCA1) in PTX resistance of BC.

Methods

UCA1, microRNA-613 (miR-613) and cyclin-dependent kinase 12 (CDK12) expression was assayed through quantitative real-time polymerase chain reaction (qRT-PCR). Cell Counting Kit-8 (CCK-8) assay was implemented for evaluating the half inhibitory concentrations (IC₅₀) of PTX and cell viability. Cell apoptosis was examined by flow cytometry. The target relationship was explored using dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. CDK12 protein level was detected through Western blot. Xenograft tumor assay was applied for assessing the influence of UCA1 on PTX resistance of BC in vivo.

Results

UCA1 expressed highly in PTX-resistant BC tissues and cells and regulated PTX resistance in BC cells by affecting cell viability and apoptosis in part. UCA1 negatively interacted with miR-613 and modulated PTX resistance via sponging miR-613. CDK12 was a downstream gene of miR-613 and miR-613 exerted the modulation of PTX resistance via targeting CDK12. Furthermore, UCA1 regulated CDK12 level through interacting with miR-613. The regulatory role of UCA1 in PTX resistance of BC was achieved by miR-613/CDK12 axis in vivo.

Conclusion

UCA1 mediated PTX resistance in BC through the miR-613/CDK12 axis, manifesting that UCA1 might improve the PTX treatment of BC as a significant therapeutic biomarker.

Nrf2/ARE pathway activation is involved in negatively regulating heat-induced apoptosis in non-small cell lung cancer cells

Hyperthermia, particularly in combination with chemoradiotherapy, is widely used to treat various cancers. However, hyperthermia treatment is often insufficient due to thermo-tolerance. To date, the detailed mechanism underlying thermo-tolerance has not been clarified. The nuclear factor erythroid 2-related factor 2 (Nrf2)/ antioxidant response element (ARE) pathway is an important cellular cytoprotective defense system that is activated by various stresses. In this study, using immunocytochemistry and western blot analysis, we demonstrated that heat stress induced Nrf2/ARE activation through the nuclear translocation of Nrf2 in non-small cell lung cancer cells. Luciferase activity was also increased. Additionally, antioxidant enzymes were increased through Nrf2 activation after heat stress. Transfection of lung cancer cells with siRNA directed against Nrf2 increased heat cytotoxicity and cell apoptosis. Heat stress could induce reactive oxygen species (ROS) accumulation, while the antioxidant NAC obviously reduced cell apoptosis ratio, indicating that heat stress induced cell apoptosis in a ROS-dependent manner. Knockdown of Nrf2 led to an abnormal elevation of ROS, and the antioxidant NAC could increase Nrf2 activation, indicating that ROS and Nrf2 act within a negative feedback loop. Taken together, these results demonstrated that Nrf2 pathway is important for maintaining resistance to heat stress, and we postulated that Nrf2 may represent a potential therapeutic target for hyperthermia in lung cancer.

Hyperthermia can alter tumor physiology and improve chemo- and radio-therapy efficacy

Hyperthermia has demonstrated clinical success in improving the efficacy of both chemo- and radio-therapy in solid tumors. Pre-clinical and clinical research studies have demonstrated that targeted hyperthermia can increase tumor blood flow and increase the perfused fraction of the tumor in a temperature and time dependent manner. Changes in tumor blood circulation can produce significant physiological changes including enhanced vascular permeability, increased oxygenation, decreased interstitial fluid pressure, and reestablishment of normal physiological pH conditions. These alterations in tumor physiology can positively impact both small molecule and nanomedicine chemotherapy accumulation and distribution within the tumor, as well as the fraction of the tumor susceptible to radiation therapy. Hyperthermia can trigger drug release from thermosensitive formulations and further improve the accumulation, distribution, and efficacy of chemotherapy.

Heat-activated drug delivery increases tumor accumulation of synergistic chemotherapies

Doxorubicin is a clinically important anthracycline chemotherapeutic agent that is used to treat many cancers. Nanomedicine formulations including Doxil® and ThermoDox® have been developed to mitigate doxorubicin cardiotoxicity. Doxil is used clinically to treat ovarian cancer, AIDS-related Kaposi's sarcoma, and multiple myeloma, but there is evidence that therapeutic efficacy is hampered by lack of drug release. ThermoDox is a lipid-based heat-activated formulation of doxorubicin that relies on externally applied energy to increase tissue temperatures and efficiently trigger drug release, thereby affording therapeutic advantages compared to Doxil. However, elevating tissue temperatures is a complex treatment process requiring significant time, cost, and expertise compared to standard intravenous chemotherapy. This work endeavors to develop a companion therapeutic to ThermoDox that also relies on heat-triggered release in order to increase the therapeutic index of doxorubicin. To this end, a thermosensitive liposome formulation of the heat shock protein 90 inhibitor alvespimycin has been developed and characterized. This research demonstrates that both doxorubicin and alvespimycin are potent anti-cancer agents and that heat amplifies their cytotoxic effects. Furthermore, the two drugs are proven to act synergistically when cancer cells are treated with the drugs in combination. The formulation of alvespimycin was rationally designed to exhibit similar pharmacokinetics and drug release kinetics compared to ThermoDox, enabling the two drugs to be delivered to heated tumors at similar efficiencies resulting in control of a particular synergistic ratio of drugs. In vivo measurements demonstrated effective heat-mediated triggering of doxorubicin and alvespimycin release from thermosensitive liposomes within tumor vasculature. This treatment strategy resulted in a ~10-fold increase in drug concentration within tumors compared to free drug administered without tumor heating.

Inhibition of miR‑214 attenuates the migration and invasion of triple‑negative breast cancer cells

Triple‑negative breast cancer (TNBC) is a subtype of breast cancer. MicroRNA (miR)‑214 is closely associated with controlling the development of tumor cells; therefore, in the present study, the target gene and effects of miR‑214 on TNBC cells were explored. Luciferase activity was examined by luciferase reporter assay. The viability, invasion and migration of MDA‑MB‑231 TNBC cells were measured using Cell Counting kit‑8, Transwell and wound‑healing assays, respectively. The expression levels of various factors were determined using reverse transcription‑quantitative polymerase chain reaction and western blotting. The results demonstrated that the expression levels of miR‑214 were higher and the levels of α1‑antitrypsin (α1‑AT) were lower in TNBC tissues compared with in normal tissues. Subsequently, α1‑AT was revealed to be a target of miR‑214. Furthermore, inhibition of miR‑214 decreased cell viability, invasion and migration, enhanced the expression of E‑cadherin and tissue inhibitor of metalloproteinases‑2, and reduced the expression of metastatic tumour antigen 1 and matrix metalloproteinase‑2. Inhibition of miR‑214 also significantly downregulated the phosphorylation of protein kinase B (Akt) and mammalian target of rapamycin (mTOR), and markedly downregulated that of phosphoinositide 3‑kinase (PI3K); however, the expression levels of total PI3K, Akt and mTOR remained stable in all groups. Taken together, these findings indicated that α1‑AT may be a target of miR‑214. Downregulation of miR‑214 markedly suppressed the viability, migration and invasion of MDA‑MB‑231 cells, and inhibited the PI3K/Akt/mTOR pathway. These findings suggested that miR‑214 targeting α1‑AT may be a potential mechanism underlying TNBC development.

Western Analysis of Breast Cancer 1 Protein (BRCA1)

Known for its tumor suppressor activity in breast and ovarian cancers, the breast cancer 1 susceptibility gene (Brca1) is involved in a variety of cellular pathways including DNA repair, antioxidant signaling, apoptosis, and cell cycle regulation. BRCA1 can translocate between the cytoplasm and nucleus to perform its various roles. Herein is a procedure for measuring BRCA1 protein levels in the whole cell lysate (WCL), as well as in the nuclear (N) and cytoplasmic (C) fractions of mouse tissues at different gestational ages. The method employs multiple loading controls to ensure proper separation of fractions and a total protein stain for more consistent comparisons of dissimilar samples. This method is useful for identifying BRCA1 deficiencies and localization in a variety of research fields, including development, neurodegeneration, and cancer.

A platinum(iv) prodrug to defeat breast cancer through disrupting vasculature and inhibiting metastasis

A Pt^IV prodrug bearing a vascular disrupting agent demonstrates antiangiogenic and antimetastatic potentialities against metastatic triple-negative breast cancer cells.

Thermo-Sensitive Nanomaterials: Recent Advance in Synthesis and Biomedical Applications

Progress in nanotechnology has enabled us to open many new fronts in biomedical research by exploiting the peculiar properties of materials at the nanoscale. The thermal sensitivity of certain materials is a highly valuable property because it can be exploited in many promising applications, such as thermo-sensitive drug or gene delivery systems, thermotherapy, thermal biosensors, imaging, and diagnosis. This review focuses on recent advances in thermo-sensitive nanomaterials of interest in biomedical applications. We provide an overview of the different kinds of thermoresponsive nanomaterials, discussing their potential and the physical mechanisms behind their thermal response. We thoroughly review their applications in biomedicine and finally discuss the current challenges and future perspectives of thermal therapies.