Antitumor effects of high-temperature hyperthermia on a glioma rat model

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.

Temperature-controlled magnetic nanoparticles hyperthermia inhibits primary tumor growth and metastases dissemination

Magnetic hyperthermia (MHT) is a promising approach for cancer therapy. However, a systematic MHT characterization as function of temperature on the therapeutic efficiency is barely analyzed. Here, we first perform comparative temperature-dependent analysis of the cobalt ferrite nanoparticles-mediated MHT effectiveness in two murine tumors models - breast (4T1) and colon (CT26) cancer in vitro and in vivo. The overall MHT killing capacity in vitro increased with the temperature and CT26 cells were more sensitive than 4T1 when heated to 43 °C. Well in line with the in vitro data, such heating cured non-metastatic CT26 tumors in vivo, while only inhibiting metastatic 4T1 tumor growth without improving the overall survival. High-temperature MHT (>47 °C) resulted in complete 4T1 primary tumor clearance, 25-40% long-term survival rates, and, importantly, more effective prevention of metastasis comparing to surgical extraction. Thus, the specific MHT temperature must be defined for each tumor individually to ensure a successful antitumor therapy.

Armillariella Oral Solution Ameliorates Small Intestinal Damage in a Mouse Model of Chemotherapy-Induced Mucositis

Background: Armillariella oral solution (AOS) shows therapeutic effect on gastrointestinal disorders. We aimed to investigate the potential efficacy of AOS on chemotherapy-induced intestinal mucositis in mice. Methods: Intestinal mucositis was induced in C57BL/6 mice by daily intraperitoneal injection of 5-FU (50 mg/kg) for 7 days. Effects of AOS (at 1, 5, and 10 mL/kg), or combined Bifidobacterium and Lactobacillus (CBL, 450 mg/kg) on the accompanying morphometry and histology, expression of Ki-67, caspase-3, Lgr5 and apoptosis of intestinal crypt cells were assessed. Results: Continuous administration of 5-FU to mice caused severe intestinal mucositis, which was histologically characterized by the destruction of intestinal crypts and shortening of villi, accompanied by diarrhea and body weight loss. Daily AOS administration dose-dependently reduced the severity of intestinal mucositis, diarrhea and body weight loss. Similar beneficial effects were observed with CBL. The expression of Ki-67 and Lgr5 decreased and the expression of caspase-3, and the number of apoptotic cells increased 24 h after the first 5-FU administration (P < 0.05), and these responses were significantly reduced by AOS treatment (P < 0.05, at 5 or 10 mL/kg). Conclusions: AOS can alleviate 5-FU-induced mucositis in mice via increasing Lgr5 expression and suppressing apoptotic responses in the intestinal crypt cells.

pH/NIR-Responsive Polypyrrole-Functionalized Fibrous Localized Drug-Delivery Platform for Synergistic Cancer Therapy

Localized drug-delivery systems (LDDSs) are a promising approach for cancer treatment because they decrease systematic toxicity and enhance the therapeutic effect of the drugs via site-specific delivery of active compounds and possible gradual release. However, the development of LDDS with rationally controlled drug release and intelligent functionality holds great challenge. To this end, we have developed a tailorable fibrous site-specific drug-delivery platform functionalized with pH- and near-infrared (NIR)-responsive polypyrrole (PPy), with the aim of cancer treatment via a combination of photothermal ablation and chemotherapy. First, a paclitaxel (PTX)-loaded polycaprolactone (PCL) (PCL-PTX) mat was prepared by electrospinning and subsequently in situ membrane surface-functionalized with different concentrations of PPy. The obtained PPy-functionalized mats exhibited excellent photostability and heating property in response to NIR exposure. PPy-coated mats exhibited enhanced PTX release in a pH 5.5 environment compared to pH 7.4. Release was further accelerated in response to NIR under both conditions; however, superior release was observed at pH 5.5 compared to pH 7.4, indicating a dual stimuli-responsive (pH and NIR) drug-delivery platform. More importantly, the 808 nm NIR irradiation enabled markedly accelerated PTX release from PPy-coated PCL-PTX mats and slowed and sustained release following termination of laser irradiation, confirming representative stepwise drug-release properties. PPy-coated PCL-PTX mats presented significantly enhanced in vitro and in vivo anticancer efficacy under NIR irradiation compared to PPy-coated PCL-PTX mats not exposed to NIR or uncoated mats (PCL-PTX). This study has thus developed a promising fibrous site-specific drug-delivery platform with NIR- and pH-triggering that notably utilizes PPy as a dopant for synergistic photothermal chemotherapy.

Oral Administration of Surface-Deacetylated Chitin Nanofibers and Chitosan Inhibit 5-Fluorouracil-Induced Intestinal Mucositis in Mice

This study investigated the prophylactic effects of orally administered surface-deacetylated chitin nanofibers (SDACNFs) and chitosan against 5-fluorouracil (5-FU)-induced intestinal mucositis, which is a common side effect of 5-FU chemotherapy. SDACNFs and chitosan abolished histological abnormalities associated with intestinal mucositis and suppressed hypoproliferation and apoptosis of intestinal crypt cells. These results indicate that SDACNF and chitosan are useful agents for preventing mucositis induced by anti-cancer drugs.

Tailoring La1−xSrxMnO3(0.25 ≤ x ≤ 0.35) nanoparticles for self-regulating magnetic hyperthermia therapy: an in vivo study

Silica-coated La_1−xSr_xMnO₃(0.25 ≤x≤ 0.35) nanoparticles were designed for self-regulating magnetic hyperthermia therapy. The efficacy of the prepared nanoparticles was investigated on a typical animal model of breast cancer.

Investigation of terahertz radiation influence on rat glial cells

We studied an influence of continuous terahertz (THz) radiation (0.12 - 0.18 THz, average power density of 3.2 mW/cm²) on a rat glial cell line. A dose-dependent cytotoxic effect of THz radiation is demonstrated. After 1 minute of THz radiation exposure a relative number of apoptotic cells increased in 1.5 times, after 3 minutes it doubled. This result confirms the concept of biological hazard of intense THz radiation. Diagnostic applications of THz radiation can be restricted by the radiation power density and exposure time.

Selective delivery of photothermal nanoparticles to tumors using mesenchymal stem cells as Trojan horses

Mesenchymal stem cells can be usedin vivoas carriers of photothermal nanoparticles thanks to their ability to migrate and incorporate into tumors. A superior ablative effect is reached when using this strategy compared to the EPR effect.

Blood brain barrier: An overview on strategies in drug delivery, realistic in vitro modeling and in vivo live tracking

Blood brain barrier (BBB) is a group of astrocytes, neurons and endothelial cells, which makes restricted passage of various biological or chemical entities to the brain tissue. It gives protection to brain at one hand, but at the other hand it has very selective permeability for bio-actives and other foreign materials and is one of the major challenges for the drug delivery. Nanocarriers are promising to cross BBB utilizing alternative route of administration such as intranasal and intra-carotid drug delivery which bypasses BBB. In future more optimized drug delivery system can be achieved by compiling the best routes with the best carriers. Single photon emission tomography (SPECT) and different brain-on-a-chip in vitro models are being very reliable to study live in vivo tracking of BBB and its pathophysiology, respectively. In the current review we have tried to exploit mechanistically all these to understand and manage the various BBB disruptions in diseased condition along with crossing the hurdles occurring in drug or gene delivery across BBB.

Local recurrence of small cell lung cancer following radiofrequency ablation is induced by HIF-1α expression in the transition zone

Local recurrence of lung cancer following radiofrequency ablation (RFA) treatment is common. The aims of the present study were to assess how RFA treatment affects the growth of small cell lung cancer (SCLC) micrometastases in the transition zone (TZ) surrounding the ablated region and in the reference zones (RZs) of the ablated or unablated lobes and to identify the molecular mechanism(s) of lung cancer recurrence following RFA treatment. After lung micrometastases of human SCLCs had formed, RFA treatment was applied to the right upper lobe (RUL) of the lung in nude mice. Hypoxia inducible factor (HIF)-1α expression, proliferation and angiogenesis potential both in the TZ and RZ were evaluated over time. Separately, at day 1, 7 and 14 following RFA treatment, the growth of micrometastases showed an ~2-fold increase in the TZ compared to the RZ of the unablated lobe, as the right lower lobe (RLL) and the growth of micrometastases in the RZ of the RUL was also induced by RFA. In addition, accelerated tumor growth in the TZ was induced by HIF-1α, but was not associated with tissue angiogenesis potential. We concluded that local recurrences of SCLCs caused by overproliferation of micrometastases following RFA treatment were driven by HIF-1α, although angiogenesis was not the driving force in the TZ.

Drug delivery strategies to enhance the permeability of the blood-brain barrier for treatment of glioma

Gliomas are amongst the most insidious and destructive types of brain cancer and are associated with a poor prognosis, frequent recurrences, and extremely high lethality despite combination treatment of surgery, radiotherapy, and chemotherapy. The existence of the blood–brain barrier (BBB) restricts the delivery of therapeutic molecules into the brain and offers the clinical efficacy of many pharmaceuticals that have been demonstrated to be effective for other kinds of tumors. This challenge emphasizes the need to be able to deliver drugs effectively across the BBB to reach the brain parenchyma. Enhancement of the permeability of the BBB and being able to transport drugs across it has been shown to be a promising strategy to improve drug absorption and treatment efficacy. This review highlights the innovative technologies that have been introduced to enhance the permeability of the BBB and to obtain an optimal distribution and concentration of drugs in the brain to treat gliomas, such as nanotechniques, hyperthermia techniques, receptor-mediated transport, cell-penetrating peptides, and cell-mediated delivery.

High temperature hyperthermia treatment for canines exhibiting superficial tumors: A report of three cases

High temperature hyperthermia (HTH) treatment has previously been demonstrated to suppress tumor growth in a tumor-bearing rat model. In the present study, the effects of HTH therapy for the treatment of spontaneous tumors in canines was evaluated. In case 1, an 18-year-old female Papillon presented with a right forelimb rhabdomyosarcoma. Case 2 was a 13-year-old male English Cocker Spaniel with a right external auditory canal ceruminous adenocarcinoma and case 3 was a 14-year-old male Golden Retriever that exhibited a perianal gland adenocarcinoma, which surrounded the anus. HTH treatment was performed in all three cases for 10 min at 45–65°C with or without the inhalation of isoflurane. In case 1, the tumor disappeared four weeks following HTH treatment. In case 2, the tumor volume had decreased by day 21, and in case 3, HTH was performed three times and the tumor disappeared following the third procedure. HTH is considered to be a simple procedure with no severe side effects. Consequently, this treatment modality is hypothesized to become a useful alternative therapy for superficial tumors in companion animals.

Non-surgical treatment of canine oral malignant melanoma: A case study of the application of complementary alternative medicine

This report describes a dog with a clinical stage III oral malignant melanoma that was treated with complementary alternative medicine (CAM). The CAM included high temperature hyperthermia, dendritic cell therapy and lupeol injections. Surgery, radiation and chemotherapy were not performed. Two months after the start of treatment, the tumor disappeared and after six months, the follow-up examinations revealed no recurrence or metastasis of the tumor. Quality of life (QOL) of the dog was maintained; therefore, the application of CAM may be an effective treatment for canine oral malignant melanoma. The effective application of CAM has the potential to prolong life and maintain an excellent QOL for pets.