Thermochemotherapy in patients with extremity high-risk soft tissue sarcomas (HR-STS)

Combination Treatment with Liposomal Doxorubicin and Inductive Moderate Hyperthermia for Sarcoma Saos-2 Cells

Despite efforts in osteosarcoma (OS) research, the role of inductive moderate hyperthermia (IMH) in delivering and enhancing the antitumor effect of liposomal doxorubicin formulations (LDOX) remains unresolved. This study investigated the effect of a combination treatment with LDOX and IMH on Saos-2 human OS cells. We compared cell viability using a trypan blue assay, apoptosis and reactive oxygen species (ROS) measured by flow cytometry and pro-apoptotic Bax protein expression examined by immunocytochemistry in response to IMH (42 MHz frequency, 15 W power for 30 min), LDOX (0.4 μg/mL), and LDOX plus IMH. The lower IC50 value of LDOX at 72 h indicated increased accumulation of the drug in the OS cells. LDOX plus IMH resulted in a 61% lower cell viability compared to no treatment. Moreover, IMH potentiated the LDOX action on the Saos-2 cells by promoting ROS production at temperatures of <42 °C. There was a 12% increase in cell populations undergoing early apoptosis with a less heterogeneous distribution of Bax after combination treatment compared to those treated with LDOX (p < 0.05). Therefore, we determined that IMH could enhance LDOX delivery and its antitumor effect via altered membrane permeabilization, ROS generation, and a lower level of visualized Bax heterogeneity in the Saos-2 cells, suggesting the potential translation of these findings into in vivo studies.

A Narrative Review of Regional Hyperthermia: Updates From 2010 to 2019

The role of hyperthermia (HT) in cancer therapy and palliative care has been discussed for years in the literature. There are plenty of articles that show good feasibility of HT and its efficacy in terms of tumor response and survival improvements. Nevertheless, HT has never gained enough interest among oncologists to become a standard therapy in clinical practice. The main advantage of HT is the enhancement of chemotherapy (CHT), radiotherapy (RT), chemoradiotherapy (CRT), and immunotherapy benefits. This effect has been confirmed in several types of tumors: esophageal, gastrointestinal, pancreas, breast, cervix, head and neck, and bladder cancers, and soft tissue sarcoma. HT effects include oxygenation and perfusion changes, DNA repair inhibition and immune system activation as a consequence of new antigen exposure. The literature shows a wide variety of randomized, nonrandomized, and observational studies and both prospective and retrospective data to confirm the advantage of HT association to CHT and RT. There are still many ongoing trials on this subject. This article summarizes the available literature on HT in order to update the current knowledge on HT use in association with RT and/or CHT from 2010 up to 2019.

Radiofrequency deep hyperthermia combined with chemotherapy in the treatment of advanced non-small cell lung cancer

Background

In the era of precision medicine, chemotherapy is still considered the cornerstone of treatment for lung cancer patients without gene mutations. How to reduce the toxicity and increase the efficiency of chemotherapy is worth exploring. This study aimed to investigate the curative effects and safety of hyperthermia combined with chemotherapy (HCT) for advanced patients with non-small cell lung cancer (NSCLC), especially those with malignant pleural effusion.

Methods

We retrospectively evaluated medical records of 93 patients with advanced NSCLC (stage IIIB-IV) from March 2011 to January 2014. The patients were divided into HCT and chemotherapy (CT) groups. The HCT group was treated with gemcitabine and cisplatin (GP) regimen combined with regional radiofrequency deep hyperthermia, while the CT group was treated with GP regimen only. Those with malignant pleural effusion extra underwent thoracentesis and intrapleural injection chemotherapy combined with hyperthermic or not. Clinical treatment results and adverse reactions were compared and analyzed after treatment. SPSS 19.0 software (SPSS Inc., USA) was used for statistical data processing. P values less than 0.05 were accepted to be statistically significant.

Results

Among the 93 patients, HCT group included 48 patients (16 patients with malignant pleural effusion), CT group included 45 patients (10 patients with malignant pleural effusion). There was no significant difference between the two groups in patient characteristics. The overall response rate (ORR) of pleural effusions was much better in HCT group than that in CT group (81.2% vs. 40.0%, P = 0.046). The patients in HCT group had lower incidence rate of weakness (12.5% vs. 46.7%, χ² = 13.16, P < 0.001) and gastrointestinal (25.0% vs. 77.8%, χ² = 25.88, P < 0.001) adverse reactions than that in CT group. The objective tumor response and survival showed no significant differences.

Conclusions

Hyperthermia combined with chemotherapy might lead to the development of better therapeutic strategy for advanced NSCLC with malignant pleural effusion patients. Also, it could greatly reduce the chemotherapy toxic effects in the incidence of weakness and gastrointestinal adverse reactions in advanced NSCLC patients.

Overcoming limitations in nanoparticle drug delivery: triggered, intravascular release to improve drug penetration into tumors

Traditionally, the goal of nanoparticle-based chemotherapy has been to decrease normal tissue toxicity by improving drug specificity to tumors. The enhanced permeability and retention effect can permit passive accumulation into tumor interstitium. However, suboptimal delivery is achieved with most nanoparticles because of heterogeneities of vascular permeability, which limits nanoparticle penetration. Furthermore, slow drug release limits bioavailability. We developed a fast drug-releasing liposome triggered by local heat that has already shown substantial antitumor efficacy and is in human trials. Here, we show that thermally sensitive liposomes (Dox-TSL) release doxorubicin inside the tumor vasculature. Real-time confocal imaging of doxorubicin delivery to murine tumors in window chambers and histologic analysis of flank tumors illustrates that intravascular drug release increases free drug in the interstitial space. This increases both the time that tumor cells are exposed to maximum drug levels and the drug penetration distance, compared with free drug or traditional pegylated liposomes. These improvements in drug bioavailability establish a new paradigm in drug delivery: rapidly triggered drug release in the tumor bloodstream.

Induction of a tumour-specific CTL response by exosomes isolated from heat-treated malignant ascites of gastric cancer patients

PURPOSE

Tumour cell-derived exosomes may represent a novel type of cancer vaccine. However, the immunogenicity of exosomes derived from tumour cells has been shown to be poor. Therefore, in this study, exosome immunogenicity following heat treatment of exosomes from malignant ascites obtained from gastric cancer patients was evaluated.

MATERIALS AND METHODS

Tumour-derived exosomes were isolated from heat-treated and untreated malignant ascites of gastric cancer patients using serial centrifugation and sucrose gradient ultracentrifugation. Next, in vitro experiments were performed to investigate the influence of heat treatment on exosome immunogenicity.

RESULTS

Exosomes from heat-treated malignant ascites of gastric cancer patients (HS exosomes) were found to contain higher concentrations of heat shock proteins, Hsp70 and Hsp60, than exosomes derived from untreated malignant ascites obtained from gastric cancer patients. Additional in vitro studies suggest that exosomes derived from heat-treated malignant ascites are able to promote dendritic cell (DC) maturation and induce a tumour-specific cytotoxic T lymphocyte (CTL) response.

CONCLUSIONS

Overall, these results demonstrate that exposure to heat stress can improve the immunogenicity of exosomes obtained from malignant ascites of gastric cancer patients.

Radiosensitization of cancer cells by hydroxychalcones

Radiation sensitization is significantly increased by proteotoxic stress, such as a heat shock. We undertook an investigation, seeking to identify natural products that induced proteotoxic stress and then determined if a compound exhibited radiosensitizing properties. The hydroxychalcones, 2',5'-dihydroxychalcone (D-601) and 2,2'-dihydroxychalcone (D-501), were found to activate heat shock factor 1 (Hsf1) and exhibited radiation sensitization properties in colon and pancreatic cancer cells. The radiosensitization ability of D-601 was blocked by pretreatment with α-napthoflavone (ANF), a specific inhibitor of cytochrome P450 1A2 (CYP1A2), suggesting that the metabolite of D-601 is essential for radiosensitization. The study demonstrated the ability of hydroxychalcones to radiosensitize cancer cells and provides new leads for developing novel radiation sensitizers.